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Aloj L, Mansi R, De Luca S, Accardo A, Tesauro D, Morelli G. Radiolabeled peptides and their expanding role in clinical imaging and targeted cancer therapy. J Pept Sci 2024:e3607. [PMID: 38710638 DOI: 10.1002/psc.3607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 03/29/2024] [Accepted: 04/01/2024] [Indexed: 05/08/2024]
Abstract
There is an expanding body of evidence showing that synthetic peptides in combination with radioactive isotopes can be utilized for medical purposes. This area is of particular interest in oncology where applications in diagnosis and therapy are at different stages of development. We review the contributions in this area by the group originally founded by Carlo Pedone in Naples many years ago. We highlight the work of this group in the context of other developments in this area, focusing on three biologically relevant receptor systems: somatostatin, gastrin-releasing peptide, and cholecystokinin-2/gastrin receptors. We focus on key milestones, state of the art, and challenges in this area of research as well as the current and future outlook for expanding clinical applications.
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Affiliation(s)
- Luigi Aloj
- Department of Radiology, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Rosalba Mansi
- Division of Radiopharmaceutical Chemistry, Clinic of Radiology and Nuclear Medicine, University Hospital Basel, Basel, Switzerland
| | - Stefania De Luca
- Institute of Biostructures and Bioimaging (IBB), CNR, Naples, Italy
| | - Antonella Accardo
- Department of Pharmacy and CIRPeB, Research Centre on Bioactive Peptides "Carlo Pedone", University of Naples "Federico II", Naples, Italy
| | - Diego Tesauro
- Department of Pharmacy and CIRPeB, Research Centre on Bioactive Peptides "Carlo Pedone", University of Naples "Federico II", Naples, Italy
| | - Giancarlo Morelli
- Department of Pharmacy and CIRPeB, Research Centre on Bioactive Peptides "Carlo Pedone", University of Naples "Federico II", Naples, Italy
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Andersen IV, Bidesi NSR, Shalgunov V, Jørgensen JT, Gustavsson T, Strømgaard K, Ingemann Jensen AT, Kjær A, Herth MM. Investigation of imaging the somatostatin receptor by opening the blood-brain barrier with melittin - A feasibility study using positron emission tomography and [ 64Cu]Cu-DOTATATE. Nucl Med Biol 2024; 132-133:108905. [PMID: 38555651 DOI: 10.1016/j.nucmedbio.2024.108905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 02/28/2024] [Accepted: 03/17/2024] [Indexed: 04/02/2024]
Abstract
DOTATATE is a somatostatin peptide analog used in the clinic to detect somatostatin receptors which are highly expressed on neuroendocrine tumors. Somatostatin receptors are found naturally in the intestines, pancreas, lungs, and brain (mainly cortex). In vivo measurement of the somatostatin receptors in the cortex has been challenging because available tracers cannot cross the blood-brain barrier (BBB) due to their intrinsic polarity. A peptide called melittin, a main component of honeybee venom, has been shown to disrupt plasma membranes and increase the permeability of biological membranes. In this study, we assessed the feasibility of using melittin to facilitate the passage of [64Cu]Cu-DOTATATE through the BBB and its binding to somatostatin receptors in the cortex. Evaluation included in vitro autoradiography on Long Evans rat brains to estimate the binding affinity of [64Cu]Cu-DOTATATE to the somatostatin receptors in the cortex and an in vivo evaluation of [64Cu]Cu-DOTATATE binding in NMRI mice after injection of melittin. This study found an in vitro Bmax = 89 ± 4 nM and KD = 4.5 ± 0.6 nM in the cortex, resulting in a theoretical binding potential (BP) calculated as Bmax/KD ≈ 20, which is believed suitable for in vivo brain PET imaging. However, the in vivo results showed no significant difference between the control and melittin injected mice, indicating that the honeybee venom failed to open the BBB. Additional experiments, potentially involving faster injection rates are required to verify that melittin can increase brain uptake of non-BBB permeable PET tracers. Furthermore, an evaluation of whether a venom with a narrow therapeutic range can be used for clinical purposes needs to be considered.
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Affiliation(s)
- Ida Vang Andersen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark
| | - Natasha Shalina Rajani Bidesi
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark
| | - Vladimir Shalgunov
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark; Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Jesper Tranekjær Jørgensen
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark; Cluster for Molecular Imaging, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Tobias Gustavsson
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark
| | - Kristian Strømgaard
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark
| | - Andreas T Ingemann Jensen
- Center for Nanomedicine and Theranostics, DTU Health Technology Technical University of Denmark (DTU) Ørsteds Plads 345C, 2800 Lyngby, Denmark
| | - Andreas Kjær
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark; Cluster for Molecular Imaging, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Matthias M Herth
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 160, 2100 Copenhagen, Denmark; Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark.
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Santo G, Di Santo G, Virgolini I. Peptide Receptor Radionuclide Therapy of Neuroendocrine Tumors: Agonist, Antagonist and Alternatives. Semin Nucl Med 2024:S0001-2998(24)00013-8. [PMID: 38490913 DOI: 10.1053/j.semnuclmed.2024.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 02/14/2024] [Accepted: 02/14/2024] [Indexed: 03/17/2024]
Abstract
Peptide receptor radionuclide therapy (PRRT) today is a well-established treatment strategy for patients with neuroendocrine tumors (NET). First performed already more than 30 years ago, PRRT was incorporated only in recent years into the major oncology guidelines, based on its proven efficacy and safety in clinical trials. Following the phase 3 NETTER-1 trial, which led to the final registration of the radiopharmaceutical Luthatera® for G1/G2 NET patients in 2017, the long-term results of the phase 3 NETTER-2 trial may pave the way for a new treatment option also for advanced G2/G3 patients as first-line therapy. The growing knowledge about the synergistic effect of combined therapies could also allow alternative (re)treatment options for NET patients, in order to create a tailored treatment strategy. The evolving thera(g)nostic concept could be applied for the identification of patients who might benefit from different image-guided treatment strategies. In this scenario, the use of dual tracer PET/CT in NET patients, using both [18F]F-FDG/[68Ga]Ga-DOTA-somatostatin analog (SSA) for diagnosis and follow-up, is under discussion and could also result in a powerful prognostic tool. In addition, alternative strategies based on different metabolic pathways, radioisotopes, or combinations of different medical approaches could be applied. A number of different promising "doors" could thus open in the near future for the treatment of NET patients - and the "key" will be thera(g)nostic!
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Affiliation(s)
- Giulia Santo
- Department of Nuclear Medicine, Medical University of Innsbruck, Innsbruck, Austria; Department of Experimental and Clinical Medicine, "Magna Graecia" University of Catanzaro, Catanzaro, Italy
| | - Gianpaolo Di Santo
- Department of Nuclear Medicine, Medical University of Innsbruck, Innsbruck, Austria
| | - Irene Virgolini
- Department of Nuclear Medicine, Medical University of Innsbruck, Innsbruck, Austria.
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Wang P, Liu S, Li X, Liu X, Li S, Wu Z, Cheng X. The usefulness of [ 68 Ga]Ga-DOTA-JR11 PET/CT in patients with meningioma: comparison with MRI. Eur J Nucl Med Mol Imaging 2023; 51:218-225. [PMID: 37682301 DOI: 10.1007/s00259-023-06391-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 08/07/2023] [Indexed: 09/09/2023]
Abstract
PURPOSE Clinical studies of PET imaging using SSTR2 agonists have demonstrated high accuracy and correlation with SSTR2 expression in meningiomas. However, the usefulness of the SSTR2 antagonist with [68 Ga]Ga-DOTA-JR11 is uncertain. To evaluate the diagnostic performance of [68 Ga]Ga-DOTA-JR11 PET/CT and to clarify tumor characteristics in patients with suspected meningiomas. MATERIALS AND METHODS Patients with suspected de novo or recurrent meningioma in complex locations or atypical images were enrolled from August 2021 to October 2022 in prospective study. All patients underwent contrast-enhanced MRI (CE-MRI), [68 Ga]Ga-DOTA-JR11 PET/CT, and histopathological evaluation. Tumor uptake of [68 Ga]Ga-DOTA-JR11 was measured by SUVmax and tumor-endocranium ratio (TBR). Diagnostic performance was compared between PET and MRI. RESULTS Of 36 (50.0 ± 13.0 years of age, 20 women) patients, 32 were histopathologically confirmed meningiomas and four with other tumors. [68 Ga]Ga-DOTA-JR11 uptake was significantly higher in meningioma patients than in those with other tumors (SUVmax: 13.6 ± 7.7 vs. 5.2 ± 3.0, P < 0.001; TBR: 64.2 ± 27.7 vs. 25.0 ± 18.9, P = 0.001). [68 Ga]Ga-DOTA-JR11 PET/CT detected 31 meningiomas, while CE-MRI detected 17 meningiomas of 25 initial diagnosis and 11 recurrent tumors; [68 Ga]Ga-DOTA-JR11 PET had an incremental diagnostic value of 24% (6/25) over MRI in the group of initial diagnosis. There was no statistically significant difference in diagnostic efficacy between PET and MRI (P = 0.45) for all 36 patients. In skull base meningiomas, PET provided a more definitive diagnosis of pituitary involvement (in 12, not in12), compared to MRI (in eight, possible in six, possible not in six, not in four). PET revealed bone involvement in all 14 patients proven by pathology, while MRI identified only 11. CONCLUSIONS [68 Ga]Ga-DOTA-JR11 PET/CT provided high image quality and presented an ideal diagnostic performance in detecting meningioma and evaluating the involvement of the pituitary and bone. The study provides valuable evidence for the use of [68 Ga]Ga-DOTA-JR11 PET/CT as a complementary imaging modality to CE-MRI in the evaluation of meningiomas.
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Affiliation(s)
- Peipei Wang
- Department of Nuclear Medicine, Beijing , Key Laboratory of Molecular Targeted Diagnosis and Therapy in Nuclear Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, 100730, China
| | - Shuai Liu
- Department of Radiation Oncology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- Beijing Neurosurgical Institute, Capital Medical University, Beijing, China
| | - Xiaojie Li
- Department of Neurosurgery, Fengtai District, Beijing Tiantan Hospital, Capital Medical University, No. 119, the West Southern 4Th Ring Road, Beijing, 100073, China
| | - Xing Liu
- Beijing Neurosurgical Institute, Capital Medical University, Beijing, China
| | - Shaowu Li
- Beijing Neurosurgical Institute, Capital Medical University, Beijing, China
- Department of Neuroradiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Zhen Wu
- Department of Neurosurgery, Fengtai District, Beijing Tiantan Hospital, Capital Medical University, No. 119, the West Southern 4Th Ring Road, Beijing, 100073, China.
| | - Xin Cheng
- Department of Nuclear Medicine, Beijing , Key Laboratory of Molecular Targeted Diagnosis and Therapy in Nuclear Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, 100730, China.
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Nelson BJB, Wilson J, Andersson JD, Wuest F. Theranostic Imaging Surrogates for Targeted Alpha Therapy: Progress in Production, Purification, and Applications. Pharmaceuticals (Basel) 2023; 16:1622. [PMID: 38004486 PMCID: PMC10674391 DOI: 10.3390/ph16111622] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 11/08/2023] [Accepted: 11/14/2023] [Indexed: 11/26/2023] Open
Abstract
This article highlights recent developments of SPECT and PET diagnostic imaging surrogates for targeted alpha particle therapy (TAT) radiopharmaceuticals. It outlines the rationale for using imaging surrogates to improve diagnostic-scan accuracy and facilitate research, and the properties an imaging-surrogate candidate should possess. It evaluates the strengths and limitations of each potential imaging surrogate. Thirteen surrogates for TAT are explored: 133La, 132La, 134Ce/134La, and 226Ac for 225Ac TAT; 203Pb for 212Pb TAT; 131Ba for 223Ra and 224Ra TAT; 123I, 124I, 131I and 209At for 211At TAT; 134Ce/134La for 227Th TAT; and 155Tb and 152Tb for 149Tb TAT.
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Affiliation(s)
- Bryce J. B. Nelson
- Department of Oncology, University of Alberta, 11560 University Ave., Edmonton, AB T6G 1Z2, Canada; (B.J.B.N.); (J.W.); (J.D.A.)
| | - John Wilson
- Department of Oncology, University of Alberta, 11560 University Ave., Edmonton, AB T6G 1Z2, Canada; (B.J.B.N.); (J.W.); (J.D.A.)
| | - Jan D. Andersson
- Department of Oncology, University of Alberta, 11560 University Ave., Edmonton, AB T6G 1Z2, Canada; (B.J.B.N.); (J.W.); (J.D.A.)
- Edmonton Radiopharmaceutical Center, Alberta Health Services, 11560 University Ave., Edmonton, AB T6G 1Z2, Canada
| | - Frank Wuest
- Department of Oncology, University of Alberta, 11560 University Ave., Edmonton, AB T6G 1Z2, Canada; (B.J.B.N.); (J.W.); (J.D.A.)
- Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, AB T6G 2E1, Canada
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Saini S, Bartels JL, Appiah JPK, Rider JH, Baumhover N, Schultz MK, Lapi SE. Optimized Methods for the Production of High-Purity 203Pb Using Electroplated Thallium Targets. J Nucl Med 2023; 64:1791-1797. [PMID: 37652545 DOI: 10.2967/jnumed.123.265976] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 07/17/2023] [Indexed: 09/02/2023] Open
Abstract
203Pb is a surrogate imaging match for 212Pb. This elementally matched pair is emerging as a suitable pair for imaging and targeted radionuclide therapy in cancer care. Because of the half-life (51.9 h) and low-energy γ-rays emitted, 203Pb is suitable for the development of diagnostic radiopharmaceuticals. The aim of this work was to optimize the production and separation of high-specific-activity 203Pb using electroplated thallium targets. We further investigated the radiochemistry optimization using a suitable chelator, tetraazacyclododecane-1,4,7-triacetic acid (DO3A), and targeting vector, VMT-α-NET (lead-specific chelator conjugated to tyr3-octreotide via a polyethylene glycol linker). Methods: Targets were prepared by electroplating of natural or enriched (205Tl) thallium metal. Scanning electron microscopy was performed to determine the structure and elemental composition of electroplated targets. Targets were irradiated with 24-MeV protons with varying current and beam time to investigate target durability. 203Pb was purified from the thallium target material using an extraction resin (lead resin) column followed by a second column using a weak cation-exchange resin to elute the lead isotope as [203Pb]PbCl2 Inductively coupled plasma mass spectrometry studies were used to further characterize the separation for trace metal contaminants. Radiolabeling efficiency was also investigated for DO3A chelator and VMT-α-NET (a peptide-based targeting conjugate). Results: Electroplated targets were prepared at a high plating density of 76-114 mg/cm2 using a plating time of 5 h. A reproducible separation method was established with a final elution in HCl (400 μL, 1 M) suitable for radiolabeling. Greater than 90% recovery yields were achieved, with an average specific activity of 37.7 ± 5.4 GBq/μmol (1.1 ± 0.1 Ci/μmol). Conclusion: An efficient electroplating method was developed to prepare thallium targets suitable for cyclotron irradiation. A simple and fast separation method was developed for routine 203Pb production with high recovery yields and purity.
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Affiliation(s)
- Shefali Saini
- Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Jennifer L Bartels
- Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Jean-Pierre K Appiah
- Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama; and
| | - Jason H Rider
- Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama; and
| | | | | | - Suzanne E Lapi
- Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama; and
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Lin Z, Zhu W, Zhang J, Miao W, Yao S, Huo L. Head-to-Head Comparison of 68Ga-NODAGA-JR11 and 68Ga-DOTATATE PET/CT in Patients with Metastatic, Well-Differentiated Neuroendocrine Tumors: Interim Analysis of a Prospective Bicenter Study. J Nucl Med 2023; 64:1406-1411. [PMID: 37474267 DOI: 10.2967/jnumed.122.264890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 04/20/2023] [Indexed: 07/22/2023] Open
Abstract
The current study aimed to compare 68Ga-NODAGA-Cpa-cyclo(d-Cys-amino-Phe-hydroorotic acid-d-4-amino-Phe(carbamoyl)-Lys-Thr-Cys)-d-Tyr-NH2 (JR11) and 68Ga-DOTATATE PET/CT in patients with metastatic, well-differentiated neuroendocrine tumors. Methods: A prospective bicenter study aimed at enrolling 100 patients with histologically proven, metastatic or unresectable, well-differentiated neuroendocrine tumors was conducted. The first 48 patients represented the study cohort. Each patient received 68Ga-DOTATATE on the first day and 68Ga-NODAGA-JR11 on the second day. Whole-body PET/CT scans were performed at 40-60 min after injection. Normal-organ uptake, lesion numbers, lesion uptake, and sensitivity were compared. The potential impact on clinical management was also determined. Results: Overall, 68Ga-NODAGA-JR11 demonstrated lower background uptake in normal organs. Compared with 68Ga-DOTATATE, 68Ga-NODAGA-JR11 detected significantly more liver lesions (673 vs. 584, P = 0.002). The target-to-background ratio of liver lesions was significantly higher on 68Ga-NODAGA-JR11 (6.4 ± 8.7 vs. 3.1 ±2.6, P = 0.000). Comparable uptake was observed for primary tumors, bone lesions, and lymph node metastases. In total, 180 lesions were detected on conventional imaging in 15 patients; 165 and 139 lesions of them were positive on 68Ga-NODAGA-JR11 and 68Ga-DOTATATE, leading to a sensitivity of 91.7% and 77.2%, respectively. In 14.5% (7/48) of patients, 68Ga-NODAGA-JR11 PET might have a potential impact on clinical management. Conclusion: 68Ga-NODAGA-JR11 shows better sensitivity and a higher target-to-background ratio than 68Ga-DOTATATE. The detection of more lesions by the antagonist may have a potential impact on clinical management in a subgroup of patients.
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Affiliation(s)
- Zefang Lin
- Department of Nuclear Medicine, First Affiliated Hospital of Fujian Medical University, Fuzhou, China; and
| | - Wenjia Zhu
- Nuclear Medicine Department, State Key Laboratory of Complex Severe and Rare Diseases, Center for Rare Diseases Research, and Beijing Key Laboratory of Molecular Targeted Diagnosis and Therapy in Nuclear Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
| | - Jiaying Zhang
- Department of Nuclear Medicine, First Affiliated Hospital of Fujian Medical University, Fuzhou, China; and
| | - Weibing Miao
- Department of Nuclear Medicine, First Affiliated Hospital of Fujian Medical University, Fuzhou, China; and
| | - Shaobo Yao
- Department of Nuclear Medicine, First Affiliated Hospital of Fujian Medical University, Fuzhou, China; and
| | - Li Huo
- Nuclear Medicine Department, State Key Laboratory of Complex Severe and Rare Diseases, Center for Rare Diseases Research, and Beijing Key Laboratory of Molecular Targeted Diagnosis and Therapy in Nuclear Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China
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Handula M, Beekman S, Konijnenberg M, Stuurman D, de Ridder C, Bruchertseifer F, Morgenstern A, Denkova A, de Blois E, Seimbille Y. First preclinical evaluation of [ 225Ac]Ac-DOTA-JR11 and comparison with [ 177Lu]Lu-DOTA-JR11, alpha versus beta radionuclide therapy of NETs. EJNMMI Radiopharm Chem 2023; 8:13. [PMID: 37389800 DOI: 10.1186/s41181-023-00197-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 06/02/2023] [Indexed: 07/01/2023] Open
Abstract
BACKGROUND The [177Lu]Lu-DOTA-TATE mediated peptide receptor radionuclide therapy (PRRT) of neuroendocrine tumors (NETs) is sometimes leading to treatment resistance and disease recurrence. An interesting alternative could be the somatostatin antagonist, [177Lu]Lu-DOTA-JR11, that demonstrated better biodistribution profile and higher tumor uptake than [177Lu]Lu-DOTA-TATE. Furthermore, treatment with alpha emitters showed improvement of the therapeutic index of PRRT due to the high LET offered by the alpha particles compared to beta emitters. Therefore, [225Ac]Ac-DOTA-JR11 can be a potential candidate to improve the treatment of NETs (Graphical abstract). DOTA-JR11 was radiolabeled with [225Ac]Ac(NO3)3 and [177Lu]LuCl3. Stability studies were performed in phosphate buffered saline (PBS) and mouse serum. In vitro competitive binding assay has been carried out in U2OS-SSTR2 + cells for natLa-DOTA-JR11, natLu-DOTA-JR11 and DOTA-JR11. Ex vivo biodistribution studies were performed in mice inoculated with H69 cells at 4, 24, 48 and 72 h after injection of [225Ac]Ac-DOTA-JR11. A blocking group was included to verify uptake specificity. Dosimetry of selected organs was determined for [225Ac]Ac-DOTA-JR11 and [177Lu]Lu-DOTA-JR11. RESULTS [225Ac]Ac-DOTA-JR11 has been successfully prepared and obtained in high radiochemical yield (RCY; 95%) and radiochemical purity (RCP; 94%). [225Ac]Ac-DOTA-JR11 showed reasonably good stability in PBS (77% intact radiopeptide at 24 h after incubation) and in mouse serum (~ 81% intact radiopeptide 24 h after incubation). [177Lu]Lu-DOTA-JR11 demonstrated excellent stability in both media (> 93%) up to 24 h post incubation. Competitive binding assay revealed that complexation of DOTA-JR11 with natLa and natLu did not affect its binding affinity to SSTR2. Similar biodistribution profiles were observed for both radiopeptides, however, higher uptake was noticed in the kidneys, liver and bone for [225Ac]Ac-DOTA-JR11 than [177Lu]Lu-DOTA-JR11. CONCLUSION [225Ac]Ac-DOTA-JR11 showed a higher absorbed dose in the kidneys compared to [177Lu]Lu-DOTA-JR11, which may limit further studies with this radiopeptide. However, several strategies can be explored to reduce nephrotoxicity and offer opportunities for future clinical investigations with [225Ac]Ac-DOTA-JR11.
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Affiliation(s)
- Maryana Handula
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | - Savanne Beekman
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | - Mark Konijnenberg
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | - Debra Stuurman
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
- Department of Experimental Urology, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | - Corrina de Ridder
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
- Department of Experimental Urology, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | | | | | - Antonia Denkova
- Applied Radiation and Isotopes, Department of Radiation Science and Technology, Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands
| | - Erik de Blois
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands
| | - Yann Seimbille
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 GD, Rotterdam, The Netherlands.
- Life Sciences Division, TRIUMF, Vancouver, BC, V6T 2A3, Canada.
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Gao X, Tang Y, Chen M, Li J, Yin H, Gan Y, Zu X, Cai Y, Hu S. A prospective comparative study of [ 68Ga]Ga-RM26 and [ 68Ga]Ga-PSMA-617 PET/CT imaging in suspicious prostate cancer. Eur J Nucl Med Mol Imaging 2023; 50:2177-2187. [PMID: 36811661 DOI: 10.1007/s00259-023-06142-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 02/08/2023] [Indexed: 02/24/2023]
Abstract
PURPOSE Prostate-specific membrane antigen (PSMA)-based PET/CT imaging has limitations in the diagnosis of prostate cancer (PCa). We recruited 207 participants with suspicious PCa to perform PET/CT imaging with radiolabeled gastrin-releasing peptide receptor (GRPR) antagonist, [68Ga]Ga-RM26, and compare with [68Ga]Ga-PSMA-617 and histopathology. METHODS Every participant with suspicious PCa was scanned with both [68Ga]Ga-RM26 and [68Ga]Ga-PSMA-617 PET/CT. PET/CT imaging was compared using pathologic specimens as a reference standard. RESULTS Of the 207 participants analyzed, 125 had cancer, and 82 were diagnosed with benign prostatic hyperplasia (BPH). The sensitivity and specificity of [68Ga]Ga-RM26 and [68Ga]Ga-PSMA-617 PET/CT imaging differed significantly for detecting clinically significant PCa. The area under the ROC curve (AUC) was 0.54 for [68Ga]Ga-RM26 PET/CT and 0.91 for [68Ga]Ga-PSMA-617 PET/CT in detecting PCa. For clinically significant PCa imaging, the AUCs were 0.51 vs. 0.93, respectively. [68Ga]Ga-RM26 PET/CT imaging had higher sensitivity for PCa with Gleason score (GS) = 6 (p = 0.03) than [68Ga]Ga-PSMA-617 PET/CT but poor specificity (20.73%). In the group with PSA < 10 ng/mL, the sensitivity, specificity, and AUC of [68Ga]Ga-RM26 PET/CT were lower than [68Ga]Ga-PSMA-617 PET/CT (60.00% vs. 80.30%, p = 0.12, 23.26% vs. 88.37%, p = 0.000, and 0.524 vs. 0.822, p = 0.000, respectively). [68Ga]Ga-RM26 PET/CT exhibited significantly higher SUVmax in specimens with GS = 6 (p = 0.04) and in the low-risk group (p = 0.01), and its uptake did not increase with PSA level, GS, or clinical stage. CONCLUSION This prospective study provided evidence for the superior accuracy of [68Ga]Ga-PSMA-617 PET/CT over [68Ga]Ga-RM26 PET/CT in detecting more clinically significant PCa. [68Ga]Ga-RM26 PET/CT showed an advantage for imaging low-risk PCa.
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Affiliation(s)
- Xiaomei Gao
- Department of Pathology, Disorders of Prostate Cancer Multidisciplinary Team, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Hunan Province, No.87 Xiangya Road, Changsha City, 410008, People's Republic of China
| | - Yongxiang Tang
- Department of Nuclear Medicine, Disorders of Prostate Cancer Multidisciplinary Team, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Hunan Province, No.87 Xiangya Road, Changsha City, 410008, People's Republic of China
| | - Minfeng Chen
- Department of Urology, Disorders of Prostate Cancer Multidisciplinary Team, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Hunan Province, No.87 Xiangya Road, Changsha City, 410008, People's Republic of China
| | - Jian Li
- Department of Nuclear Medicine, Disorders of Prostate Cancer Multidisciplinary Team, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Hunan Province, No.87 Xiangya Road, Changsha City, 410008, People's Republic of China
| | - Hongling Yin
- Department of Pathology, Disorders of Prostate Cancer Multidisciplinary Team, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Hunan Province, No.87 Xiangya Road, Changsha City, 410008, People's Republic of China
| | - Yu Gan
- Department of Urology, Disorders of Prostate Cancer Multidisciplinary Team, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Hunan Province, No.87 Xiangya Road, Changsha City, 410008, People's Republic of China
| | - Xiongbin Zu
- Department of Urology, Disorders of Prostate Cancer Multidisciplinary Team, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Hunan Province, No.87 Xiangya Road, Changsha City, 410008, People's Republic of China.
| | - Yi Cai
- Department of Urology, Disorders of Prostate Cancer Multidisciplinary Team, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Hunan Province, No.87 Xiangya Road, Changsha City, 410008, People's Republic of China.
| | - Shuo Hu
- Department of Nuclear Medicine, Disorders of Prostate Cancer Multidisciplinary Team, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Hunan Province, No.87 Xiangya Road, Changsha City, 410008, People's Republic of China.
- Key Laboratory of Biological, Nanotechnology of National Health Commission, Xiangya Hospital, Central South University, Hunan Province, No.87 Xiangya Road, Changsha City, 410008, People's Republic of China.
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10
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Nock BA, Kanellopoulos P, Joosten L, Mansi R, Maina T. Peptide Radioligands in Cancer Theranostics: Agonists and Antagonists. Pharmaceuticals (Basel) 2023; 16:ph16050674. [PMID: 37242457 DOI: 10.3390/ph16050674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 04/25/2023] [Accepted: 04/27/2023] [Indexed: 05/28/2023] Open
Abstract
The clinical success of radiolabeled somatostatin analogs in the diagnosis and therapy-"theranostics"-of tumors expressing the somatostatin subtype 2 receptor (SST2R) has paved the way for the development of a broader panel of peptide radioligands targeting different human tumors. This approach relies on the overexpression of other receptor-targets in different cancer types. In recent years, a shift in paradigm from internalizing agonists to antagonists has occurred. Thus, SST2R-antagonist radioligands were first shown to accumulate more efficiently in tumor lesions and clear faster from the background in animal models and patients. The switch to receptor antagonists was soon adopted in the field of radiolabeled bombesin (BBN). Unlike the stable cyclic octapeptides used in the case of somatostatin, BBN-like peptides are linear, fast to biodegradable and elicit adverse effects in the body. Thus, the advent of BBN-like antagonists provided an elegant way to obtain effective and safe radiotheranostics. Likewise, the pursuit of gastrin and exendin antagonist-based radioligands is advancing with exciting new outcomes on the horizon. In the present review, we discuss these developments with a focus on clinical results, commenting on challenges and opportunities for personalized treatment of cancer patients by means of state-of-the-art antagonist-based radiopharmaceuticals.
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Affiliation(s)
- Berthold A Nock
- Molecular Radiopharmacy, INRaSTES, NCSR "Demokritos", 15310 Athens, Greece
| | | | - Lieke Joosten
- Department of Medical Imaging, Nuclear Medicine, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Rosalba Mansi
- Division of Radiopharmaceutical Chemistry, Clinic of Radiology and Nuclear Medicine, University Hospital Basel, 4031 Basel, Switzerland
| | - Theodosia Maina
- Molecular Radiopharmacy, INRaSTES, NCSR "Demokritos", 15310 Athens, Greece
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Ahenkorah S, Cawthorne C, Murce E, Deroose CM, Cardinaels T, Seimbille Y, Bormans G, Ooms M, Cleeren F. Direct comparison of [18F]AlF-NOTA-JR11 and [18F]AlF-NOTA-octreotide for PET imaging of neuroendocrine tumors: Antagonist versus agonist. Nucl Med Biol 2023; 118-119:108338. [PMID: 37018875 DOI: 10.1016/j.nucmedbio.2023.108338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 03/14/2023] [Accepted: 03/27/2023] [Indexed: 03/31/2023]
Abstract
BACKGROUND [18F]AlF-NOTA-octreotide is an 18F-labeled somatostatin analogue which is a good clinical alternative for 68Ga-labeled somatostatin analogues. However, radiolabeled somatostatin receptor (SSTR) antagonists might outperform agonists regarding imaging sensitivity of neuroendocrine tumors (NETs). No direct comparison between the antagonist [18F]AlF-NOTA-JR11 and the agonist [18F]AlF-NOTA-octreotide as SSTR PET probes is available. Herein, we present the radiosynthesis of [18F]AlF-NOTA-JR11 and compare its NETs imaging properties directly with the established agonist radioligand [18F]AlF-NOTA-octreotide preclinically. METHODS [18F]AlF-NOTA-JR11 was synthesized in an automated synthesis module. The in vitro binding characteristics (IC50) of [natF]AlF-NOTA-JR11 and [natF]AlF-NOTA-octreotide were evaluated and the in vitro stability of [18F]AlF-NOTA-JR11 was determined in human serum. In vitro cell binding and internalization was performed with [18F]AlF-NOTA-JR11 and [18F]AlF-NOTA-octreotide using SSTR2 expressing cells and the pharmacokinetics were evaluated using μPET/CT in mice bearing BON1.SSTR2 tumor xenografts. RESULTS Excellent binding affinity for SSTR2 was found for [natF]AlF-NOTA-octreotide (IC50 of 25.7 ± 7.9 nM). However, the IC50 value for [natF]AlF-NOTA-JR11 (290.6 ± 71 nM) was 11-fold higher compared to [natF]AlF-NOTA-octreotide, indicating lower affinity for SSTR2. [18F]AlF-NOTA-JR11 was obtained in a good RCY (50 ± 6 %) but with moderate RCP of 94 ± 1 %. [18F]AlF-NOTA-JR11 demonstrated excellent stability in human serum (>95 % after 240 min). 2.7-fold higher cell binding was observed for [18F]AlF-NOTA-JR11 as compared to [18F]AlF-NOTA-octreotide after 60 min. μPET/CT images demonstrated comparable pharmacokinetics and tumor uptake between [18F]AlF-NOTA-JR11 (SUVmax: 3.7 ± 0.8) and [18F]AlF-NOTA-octreotide (SUVmax: 3.6 ± 0.4). CONCLUSIONS [18F]AlF-NOTA-JR11 was obtained in good RCY, albeit with a moderate RCP. The cell binding study showed significant higher binding of [18F]AlF-NOTA-JR11 compared to [18F]AlF-NOTA-octreotide, despite the higher IC50 value of AlF-NOTA-JR11. However, pharmacokinetics and in vivo tumor uptake was comparable for both radiotracers. Novel Al18F-labeled derivatives of JR11 with higher SSTR2 affinity should be developed for increased tumor uptake and NET imaging sensitivity.
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[111In]In/[177Lu]Lu-AAZTA5-LM4 SST2R-Antagonists in Cancer Theranostics: From Preclinical Testing to First Patient Results. Pharmaceutics 2023; 15:pharmaceutics15030776. [PMID: 36986637 PMCID: PMC10053881 DOI: 10.3390/pharmaceutics15030776] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 03/03/2023] Open
Abstract
Aiming to expand the application of the SST2R-antagonist LM4 (DPhe-c[DCys-4Pal-DAph(Cbm)-Lys-Thr-Cys]-DTyr-NH2) beyond [68Ga]Ga-DATA5m-LM4 PET/CT (DATA5m, (6-pentanoic acid)-6-(amino)methy-1,4-diazepinetriacetate), we now introduce AAZTA5-LM4 (AAZTA5, 1,4-bis(carboxymethyl)-6-[bis(carboxymethyl)]amino-6-[pentanoic-acid]perhydro-1,4-diazepine), allowing for the convenient coordination of trivalent radiometals of clinical interest, such as In-111 (for SPECT/CT) or Lu-177 (for radionuclide therapy). After labeling, the preclinical profiles of [111In]In-AAZTA5-LM4 and [177Lu]Lu-AAZTA5-LM4 were compared in HEK293-SST2R cells and double HEK293-SST2R/wtHEK293 tumor-bearing mice using [111In]In-DOTA-LM3 and [177Lu]Lu-DOTA-LM3 as references. The biodistribution of [177Lu]Lu-AAZTA5-LM4 was additionally studied for the first time in a NET patient. Both [111In]In-AAZTA5-LM4 and [177Lu]Lu-AAZTA5-LM4 displayed high and selective targeting of the HEK293-SST2R tumors in mice and fast background clearance via the kidneys and the urinary system. This pattern was reproduced for [177Lu]Lu-AAZTA5-LM4 in the patient according to SPECT/CT results in a monitoring time span of 4–72 h pi. In view of the above, we may conclude that [177Lu]Lu-AAZTA5-LM4 shows promise as a therapeutic radiopharmaceutical candidate for SST2R-expressing human NETs, based on previous [68Ga]Ga-DATA5m-LM4 PET/CT, but further studies are needed to fully assess its clinical value. Furthermore, [111In]In-AAZTA5-LM4 SPECT/CT may represent a legitimate alternative diagnostic option in cases where PET/CT is not available.
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Makris G, Li Y, Gallazzi F, Kuchuk M, Wang J, Lewis MR, Jurisson SS, Hennkens HM. Evaluation of Re/ 99mTc-labeled somatostatin receptor-targeting peptide complexes synthesized via direct metal cyclization. RADIOCHIM ACTA 2023. [DOI: 10.1515/ract-2022-0097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Abstract
With interest in the development of somatostatin receptor (SSTR) targeting agents for potential application in diagnostic SPECT imaging (99mTc) or Peptide Radionuclide Receptor Therapy (PRRT, 186Re or 188Re) of neuroendocrine tumors, we present herein 99mTc/Re (radio)complexes synthesized by the integrated (radio)labeling approach of peptide cyclization via metal complexation. In particular, we utilized the potent SSTR2 peptide antagonist sequence DOTA-4-NO2-Phe-c(DCys-Tyr-DTrp-Lys-Thr-Cys)-DTyr-NH2 (DOTA-sst2-ANT) and report the syntheses and in vitro evaluations of its respective [99mTc]Tc/Re-cyclized peptides ([99mTc]Tc/Re-cyc-DOTA-sst2-ANT). The Re-cyc-DOTA-sst2-ANT complex was synthesized via an on-resin Re(V)-cyclization reaction using the ReOCl3(PPh3)2 precursor and consisted of three isomers characterized by LC–ESI-MS. The [99mTc]Tc-cyclized analogue was prepared via a ligand exchange reaction of the [99mTc][TcO]3+ core through a [99mTc]Tc-glucoheptonate intermediate with linear DOTA-sst2-ANT and was characterized by comparative HPLC studies against Re-cyc-DOTA-sst2-ANT. Good in vitro binding affinity was demonstrated in SSTR-expressing cells (AR42J) by the Re-cyc-DOTA-sst2-ANT major isomer, similar to the potent binder Lu-DOTA-sst2-ANT, in which the Lu metal was complexed by the bifunctional chelator DOTA versus via peptide cyclization. [99mTc]Tc-cyc-DOTA-sst2-ANT was obtained in high radiochemical yield, also with an elution pattern of three isomers observed by HPLC analysis, which were comparable yet not identical to those of Re-cyc-DOTA-sst2-ANT. The [99mTc]Tc-tracer complex was shown to be hydrophilic, and stability studies at 4 h demonstrated that it remained intact in both PBS and in rat serum, with low non-specific rat serum protein binding, while exhibiting more moderate stability in 1 mM cysteine. These findings demonstrate that direct Re/[99mTc]Tc-cyclization of DOTA-sst2-ANT is feasible and may be used as an alternative approach to the bifunctional chelate labeling strategy. However, given that the non-radioactive (Re) and radiotracer (99mTc) analogues are not identical and both form isomeric products in equilibrium, additional design modifications will be necessary prior to in vivo application of [99mTc]Tc/Re-cyc-DOTA-sst2-ANT.
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Affiliation(s)
- George Makris
- Research Reactor Center, University of Missouri , Columbia , MO 65211 , USA
| | - Yawen Li
- Department of Chemistry , University of Missouri , Columbia , MO 65211 , USA
| | - Fabio Gallazzi
- Department of Chemistry , University of Missouri , Columbia , MO 65211 , USA
- Molecular Interactions Core, University of Missouri , Columbia , MO 65211 , USA
| | - Marina Kuchuk
- Research Reactor Center, University of Missouri , Columbia , MO 65211 , USA
| | - Jing Wang
- Research Reactor Center, University of Missouri , Columbia , MO 65211 , USA
- Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics , Mianyang , Sichuan 621900 , P. R. China
| | - Michael R. Lewis
- Department of Veterinary Medicine and Surgery , University of Missouri , Columbia , MO 65211 , USA
- Research Service, Harry S. Truman Memorial Veterans’ Hospital , Columbia , MO 65201 , USA
| | - Silvia S. Jurisson
- Department of Chemistry , University of Missouri , Columbia , MO 65211 , USA
| | - Heather M. Hennkens
- Research Reactor Center, University of Missouri , Columbia , MO 65211 , USA
- Department of Chemistry , University of Missouri , Columbia , MO 65211 , USA
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Shi M, Jakobsson V, Greifenstein L, Khong PL, Chen X, Baum RP, Zhang J. Alpha-peptide receptor radionuclide therapy using actinium-225 labeled somatostatin receptor agonists and antagonists. Front Med (Lausanne) 2022; 9:1034315. [PMID: 36569154 PMCID: PMC9767967 DOI: 10.3389/fmed.2022.1034315] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 11/21/2022] [Indexed: 12/12/2022] Open
Abstract
Peptide receptor radionuclide therapy (PRRT) has over the last two decades emerged as a very promising approach to treat neuroendocrine tumors (NETs) with rapidly expanding clinical applications. By chelating a radiometal to a somatostatin receptor (SSTR) ligand, radiation can be delivered to cancer cells with high precision. Unlike conventional external beam radiotherapy, PRRT utilizes primarily β or α radiation derived from nuclear decay, which causes damage to cancer cells in the immediate proximity by irreversible direct or indirect ionization of the cells' DNA, which induces apoptosis. In addition, to avoid damage to surrounding normal cells, PRRT privileges the use of radionuclides that have little penetrating and more energetic (and thus more ionizing) radiations. To date, the most frequently radioisotopes are β- emitters, particularly Yttrium-90 (90Y) and Lutetium-177 (177Lu), labeled SSTR agonists. Current development of SSTR-targeting is triggering the shift from using SSTR agonists to antagonists for PRRT. Furthermore, targeted α-particle therapy (TAT), has attracted special attention for the treatment of tumors and offers an improved therapeutic option for patients resistant to conventional treatments or even beta-irradiation treatment. Due to its short range and high linear energy transfer (LET), α-particles significantly damage the targeted cancer cells while causing minimal cytotoxicity toward surrounding normal tissue. Actinium-225 (225Ac) has been developed into potent targeting drug constructs including somatostatin-receptor-based radiopharmaceuticals and is in early clinical use against multiple neuroendocrine tumor types. In this article, we give a review of preclinical and clinical applications of 225Ac-PRRT in NETs, discuss the strengths and challenges of 225Ac complexes being used in PRRT; and envision the prospect of 225Ac-PRRT as a future alternative in the treatment of NETs.
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Affiliation(s)
- Mengqi Shi
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Vivianne Jakobsson
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Academy for Precision Oncology, International Centers for Precision Oncology (ICPO), Wiesbaden, Germany
| | - Lukas Greifenstein
- CURANOSTICUM Wiesbaden-Frankfurt, Center for Advanced Radiomolecular Precision Oncology, Wiesbaden, Germany
| | - Pek-Lan Khong
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Xiaoyuan Chen
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Department of Surgery, Chemical and Biomolecular Engineering, and Biomedical Engineering, Yong Loo Lin School of Medicine and College of Design and Engineering, National University of Singapore, Singapore, Singapore,Agency for Science, Technology, and Research (A*STAR), Institute of Molecular and Cell Biology, Singapore, Singapore
| | - Richard P. Baum
- CURANOSTICUM Wiesbaden-Frankfurt, Center for Advanced Radiomolecular Precision Oncology, Wiesbaden, Germany
| | - Jingjing Zhang
- Department of Diagnostic Radiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Nanomedicine Translational Research Program, NUS Center for Nanomedicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,Clinical Imaging Research Centre, Centre for Translational Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore,*Correspondence: Jingjing Zhang,
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15
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Houson HA, Tekin V, Lin W, Aluicio-Sarduy E, Engle JW, Lapi SE. PET Imaging of the Neurotensin Targeting Peptide NOTA-NT-20.3 Using Cobalt-55, Copper-64 and Gallium-68. Pharmaceutics 2022; 14:pharmaceutics14122724. [PMID: 36559218 PMCID: PMC9781609 DOI: 10.3390/pharmaceutics14122724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 11/18/2022] [Accepted: 11/28/2022] [Indexed: 12/12/2022] Open
Abstract
Introduction: Neurotensin receptor 1 (NTSR1) is an emerging target for imaging and therapy of many types of cancer. Nuclear imaging of NTSR1 allows for noninvasive assessment of the receptor levels of NTSR1 on the primary tumor, as well as potential metastases. This work focuses on a the neurotensin peptide analogue NT-20.3 conjugated to the chelator NOTA for radiolabeling for use in noninvasive positron emission tomography (PET). NOTA-NT-20.3 was radiolabeled with gallium-68, copper-64, and cobalt-55 to determine the effect that modification of the radiometal has on imaging and potential therapeutic properties of NOTA-NT-20.3. Methods: In vitro assays investigating cell uptake and subcellular localization of the radiolabeled peptides were performed using human colorectal adenocarcinoma HT29 cells. In vivo PET/CT imaging was used to determine the distribution and clearance of the peptide in mice bearing NTSR1 expressing HT29 tumors. Results: Cell uptake studies showed that the highest uptake was obtained with [55Co] Co-NOTA-NT-20.3 (18.70 ± 1.30%ID/mg), followed by [64Cu] Cu-NOTA-NT-20.3 (15.46 ± 0.91%ID/mg), and lastly [68Ga] Ga-NOTA-NT-20.3 (10.94 ± 0.46%ID/mg) (p < 0.001). Subcellular distribution was similar across the three constructs, with the membranous fraction containing the highest amount of radioactivity. In vivo PET/CT imaging of the three constructs revealed similar distribution and tumor uptake at the 1 h imaging timepoint. Tumor uptake was receptor-specific and blockable by co-injection of non-radiolabeled NOTA-NT-20.3. SUV ratios of tumor to heart at the 24 h imaging timepoint show that [55Co] Co-NOTA-NT-20.3 (20.28 ± 3.04) outperformed [64Cu] Cu-NOTA-NT-20.3 (6.52 ± 1.97). In conclusion, our studies show that enhanced cell uptake and increasing tumor to blood ratios over time displayed the superiority of [55Co] Co-NOTA-NT-20.3 over [68Ga] Ga-NOTA-NT-20.3 and [64Cu] Cu-NOTA-NT-20.3 for the targeting of NTSR1.
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Affiliation(s)
- Hailey A. Houson
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Volkan Tekin
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Wilson Lin
- Department of Medical Physics, University of Wisconsin, 1111 Highland Avenue, Madison, WI 53705, USA
| | - Eduardo Aluicio-Sarduy
- Department of Medical Physics, University of Wisconsin, 1111 Highland Avenue, Madison, WI 53705, USA
| | - Jonathan W. Engle
- Department of Medical Physics, University of Wisconsin, 1111 Highland Avenue, Madison, WI 53705, USA
- Department of Radiology, University of Wisconsin, 1111 Highland Avenue, Madison, WI 53705, USA
| | - Suzanne E. Lapi
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Correspondence:
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16
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Kanellopoulos P, Nock BA, Greifenstein L, Baum RP, Roesch F, Maina T. [ 68Ga]Ga-DATA 5m-LM4, a PET Radiotracer in the Diagnosis of SST 2R-Positive Tumors: Preclinical and First Clinical Results. Int J Mol Sci 2022; 23:ijms232314590. [PMID: 36498918 PMCID: PMC9740503 DOI: 10.3390/ijms232314590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 11/21/2022] [Accepted: 11/21/2022] [Indexed: 11/24/2022] Open
Abstract
Radiolabeled somatostatin subtype 2 receptor (SST2R)-antagonists have shown advantageous profiles for cancer theranostics compared with agonists. On the other hand, the newly introduced hybrid chelator (6-pentanoic acid)-6-(amino)methyl-1,4-diazepinetriacetate (DATA5m) rapidly binds Ga-68 (t1/2: 67.7 min) at much lower temperature, thus allowing for quick access to "ready-for-injection" [68Ga]Ga-tracers in hospitals. We herein introduce [68Ga]Ga-DATA5m-LM4 for PET/CT imaging of SST2R-positive human tumors. LM4 was obtained by 4Pal3/Tyr3-substitution in the known SST2R antagonist LM3 (H-DPhe-c[DCys-Tyr-DAph(Cbm)-Lys-Thr-Cys]-DTyr-NH2) and DATA5m was coupled at the N-terminus for labeling with radiogallium (Ga-67/68). [67Ga]Ga-DATA5m-LM4 was evaluated in HEK293-SST2R cells and mice models in a head-to-head comparison with [67Ga]Ga-DOTA-LM3. Clinical grade [68Ga]Ga-DATA5m-LM4 was prepared and injected in a neuroendocrine tumor (NET) patient for PET/CT imaging. DATA5m-LM4 displayed high SST2R binding affinity. [67Ga]Ga-DATA5m-LM4 showed markedly higher uptake in HEK293-SST2R cells versus [67Ga]Ga-DOTA-LM3 and was stable in vivo. In HEK293-SST2R xenograft-bearing mice, it achieved longer tumor retention and less kidney uptake than [67Ga]Ga-DOTA-LM3. [68Ga]Ga-DATA5m-LM4 accurately visualized tumor lesions with high contrast on PET/CT. In short, [68Ga]Ga-DATA5m-LM4 has shown excellent prospects for the PET/CT diagnosis of SST2R-positive tumors, further highlighting the benefits of Ga-68 labeling in a hospital environment via the DATA5m-chelator route.
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Affiliation(s)
| | - Berthold A. Nock
- Molecular Radiopharmacy, INRaSTES, NCSR “Demokritos”, GR-15310 Athens, Greece
| | - Lukas Greifenstein
- CURANOSTICUM Wiesbaden-Frankfurt, DKD Helios Klinik, D-65191 Wiesbaden, Germany
| | - Richard P. Baum
- CURANOSTICUM Wiesbaden-Frankfurt, DKD Helios Klinik, D-65191 Wiesbaden, Germany
| | - Frank Roesch
- Department Chemie, Standort TRIGA, Johannes Gutenberg-Universität Mainz, D-55126 Mainz, Germany
| | - Theodosia Maina
- Molecular Radiopharmacy, INRaSTES, NCSR “Demokritos”, GR-15310 Athens, Greece
- Correspondence: ; Tel.: +30-210-650-3908 (ext. 3891)
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Wang K, Crona J, Beuschlein F, Grossman AB, Pacak K, Nölting S. Targeted Therapies in Pheochromocytoma and Paraganglioma. J Clin Endocrinol Metab 2022; 107:2963-2972. [PMID: 35973976 PMCID: PMC9923802 DOI: 10.1210/clinem/dgac471] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Indexed: 11/19/2022]
Abstract
Molecular targeted therapy plays an increasingly important role in the treatment of metastatic pheochromocytomas and paragangliomas (PPGLs), which are rare tumors but remain difficult to treat. This mini-review provides an overview of established molecular targeted therapies in present use, and perspectives on those currently under development and evaluation in clinical trials. Recently published research articles, guidelines, and expert views on molecular targeted therapies in PPGLs are systematically reviewed and summarized. Some tyrosine kinase inhibitors (sunitinib, cabozantinib) are already in clinical use with some promising results, but without formal approval for the treatment of PPGLs. Sunitinib is the only therapeutic option which has been investigated in a randomized placebo-controlled clinical trial. It is clinically used as a first-, second-, or third-line therapeutic option for the treatment of progressive metastatic PPGLs. Some other promising molecular targeted therapies (hypoxia-inducible factor 2 alpha [HIF2α] inhibitors, tumor vaccination together with checkpoint inhibitors, antiangiogenic therapies, kinase signaling inhibitors) are under evaluation in clinical trials. The HIF2α inhibitor belzutifan may prove to be particularly interesting for cluster 1B-/VHL/EPAS1-related PPGLs, whereas antiangiogenic therapies seem to be primarily effective in cluster 1A-/SDHx-related PPGLs. Some combination therapies currently being evaluated in clinical trials, such as temozolomide/olaparib, temozolomide/talazoparib, or cabozantinib/atezolizumab, will provide data for novel therapy for metastatic PPGLs. It is likely that advances in such molecular targeted therapies will play an essential role in the future treatment of these tumors, with more personalized therapy options paving the way towards improved therapeutic outcomes.
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Affiliation(s)
- Katharina Wang
- Department of Internal Medicine IV, University Hospital, LMU Klinikum, Ludwig Maximilian University of Munich, 80336 Munich, Germany
| | - Joakim Crona
- Department of Medical Sciences, Uppsala University, 75185 Uppsala, Sweden
| | - Felix Beuschlein
- Department of Internal Medicine IV, University Hospital, LMU Klinikum, Ludwig Maximilian University of Munich, 80336 Munich, Germany
- Department of Endocrinology, Diabetology and Clinical Nutrition, University Hospital Zurich (USZ) and University of Zurich (UZH), 8091 Zurich, Switzerland
| | - Ashley B Grossman
- Green Templeton College, University of Oxford, Oxford OX2 6HG, United Kingdom
- NET Unit, ENETS Centre of Excellence, Royal Free Hospital, London NW3 2QG, United Kingdom
| | - Karel Pacak
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892-1109, USA
| | - Svenja Nölting
- Department of Internal Medicine IV, University Hospital, LMU Klinikum, Ludwig Maximilian University of Munich, 80336 Munich, Germany
- Department of Endocrinology, Diabetology and Clinical Nutrition, University Hospital Zurich (USZ) and University of Zurich (UZH), 8091 Zurich, Switzerland
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Prosperi D, Gentiloni Silveri G, Panzuto F, Faggiano A, Russo VM, Caruso D, Polici M, Lauri C, Filice A, Laghi A, Signore A. Nuclear Medicine and Radiological Imaging of Pancreatic Neuroendocrine Neoplasms: A Multidisciplinary Update. J Clin Med 2022; 11:jcm11226836. [PMID: 36431313 PMCID: PMC9694730 DOI: 10.3390/jcm11226836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 11/14/2022] [Accepted: 11/16/2022] [Indexed: 11/22/2022] Open
Abstract
Pancreatic neuroendocrine neoplasms (panNENs) are part of a large family of tumors arising from the neuroendocrine system. PanNENs show low-intermediate tumor grade and generally high somatostatin receptor (SSTR) expression. Therefore, panNENs benefit from functional imaging with 68Ga-somatostatin analogues (SSA) for diagnosis, staging, and treatment choice in parallel with morphological imaging. This narrative review aims to present conventional imaging techniques and new perspectives in the management of panNENs, providing the clinicians with useful insight for clinical practice. The 68Ga-SSA PET/CT is the most widely used in panNENs, not only fr diagnosis and staging purpose but also to characterize the biology of the tumor and its responsiveness to SSAs. On the contrary, the 18F-Fluordeoxiglucose (FDG) PET/CT is not employed systematically in all panNEN patients, being generally preferred in G2-G3, to predict aggressiveness and progression rate. The combination of 68Ga-SSA PET/CT and 18F-FDG PET/CT can finally suggest the best therapeutic strategy. Other radiopharmaceuticals are 68Ga-exendin-4 in case of insulinomas and 18F-dopamine (DOPA), which can be helpful in SSTR-negative tumors. New promising but still-under-investigation radiopharmaceuticals include radiolabeled SSTR antagonists and 18F-SSAs. Conventional imaging includes contrast enhanced CT and multiparametric MRI. There are now enriched by radiomics, a new non-invasive imaging approach, very promising to early predict tumor response or progression.
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Affiliation(s)
- Daniela Prosperi
- Nuclear Medicine Unit, Department of Medical-Surgical Sciences and of Translational Medicine, Sant’Andrea University Hospital, Sapienza University of Rome, 00189 Roma, Italy
| | - Guido Gentiloni Silveri
- Nuclear Medicine Unit, Department of Medical-Surgical Sciences and of Translational Medicine, Sant’Andrea University Hospital, Sapienza University of Rome, 00189 Roma, Italy
| | - Francesco Panzuto
- Digestive Disease Unit, Department of Medical-Surgical Sciences and Translational Medicine, Sant’Andrea University Hospital, ENETS Center of Excellence, Sapienza University of Rome, 00189 Roma, Italy
| | - Antongiulio Faggiano
- Endocrinology Unit, Department of Clinical and Molecular Medicine, Sant’Andrea University Hospital, ENETS Center of Excellence, Sapienza University of Rome, 00189 Roma, Italy
| | - Vincenzo Marcello Russo
- Nuclear Medicine Unit, Department of Medical-Surgical Sciences and of Translational Medicine, Sant’Andrea University Hospital, Sapienza University of Rome, 00189 Roma, Italy
| | - Damiano Caruso
- Radiology Unit, Department of Medical Surgical Sciences and Translational Medicine, Sant’Andrea University Hospital, Sapienza University of Rome, 00189 Roma, Italy
| | - Michela Polici
- Radiology Unit, Department of Medical Surgical Sciences and Translational Medicine, Sant’Andrea University Hospital, Sapienza University of Rome, 00189 Roma, Italy
| | - Chiara Lauri
- Nuclear Medicine Unit, Department of Medical-Surgical Sciences and of Translational Medicine, Sant’Andrea University Hospital, Sapienza University of Rome, 00189 Roma, Italy
- Correspondence:
| | - Angelina Filice
- Nucler Medicine Unit, AUSL-IRCCS di Reggio Emilia, 42123 Reggio Emilia, Italy
| | - Andrea Laghi
- Radiology Unit, Department of Medical Surgical Sciences and Translational Medicine, Sant’Andrea University Hospital, Sapienza University of Rome, 00189 Roma, Italy
| | - Alberto Signore
- Nuclear Medicine Unit, Department of Medical-Surgical Sciences and of Translational Medicine, Sant’Andrea University Hospital, Sapienza University of Rome, 00189 Roma, Italy
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Sun J, Huangfu Z, Yang J, Wang G, Hu K, Gao M, Zhong Z. Imaging-guided targeted radionuclide tumor therapy: From concept to clinical translation. Adv Drug Deliv Rev 2022; 190:114538. [PMID: 36162696 DOI: 10.1016/j.addr.2022.114538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 09/03/2022] [Accepted: 09/11/2022] [Indexed: 01/24/2023]
Abstract
Since the first introduction of sodium iodide I-131 for use with thyroid patients almost 80 years ago, more than 50 radiopharmaceuticals have reached the markets for a wide range of diseases, especially cancers. The nuclear medicine paradigm also shifts from solely molecular imaging or radionuclide therapy to imaging-guided radionuclide therapy, which is deemed a vital component of precision cancer therapy and an emerging medical modality for personalized medicine. The imaging-guided radionuclide therapy highlights the systematic integration of targeted nuclear diagnostics and radionuclide therapeutics. Regarding this, nuclear imaging serves to "visualize" the lesions and guide the therapeutic strategy, followed by administration of a precise patient specific dose of radiotherapeutics for treatment according to the absorbed dose to different organs and tumors calculated by dosimetry tools, and finally repeated imaging to predict the prognosis. This strategy leads to significantly enhanced therapeutic efficacy, improved patient outcomes, and manageable adverse events. In this review, we provide an overview of imaging-guided targeted radionuclide therapy for different tumors such as advanced prostate cancer and neuroendocrine tumors, with a focus on development of new radioligands and their preclinical and clinical results, and further discuss about challenges and future perspectives.
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Affiliation(s)
- Juan Sun
- College of Pharmaceutical Sciences, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, People's Republic of China; Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China
| | - Zhenyuan Huangfu
- College of Pharmaceutical Sciences, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, People's Republic of China; Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China
| | - Jiangtao Yang
- College of Pharmaceutical Sciences, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, People's Republic of China; Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China
| | - Guanglin Wang
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection & School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, People's Republic of China.
| | - Kuan Hu
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Sciences, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan.
| | - Mingyuan Gao
- State Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection & School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, People's Republic of China
| | - Zhiyuan Zhong
- College of Pharmaceutical Sciences, and State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, People's Republic of China; Biomedical Polymers Laboratory, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, People's Republic of China.
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Koustoulidou S, Handula M, de Ridder C, Stuurman D, Beekman S, de Jong M, Nonnekens J, Seimbille Y. Synthesis and Evaluation of Two Long-Acting SSTR2 Antagonists for Radionuclide Therapy of Neuroendocrine Tumors. Pharmaceuticals (Basel) 2022; 15:ph15091155. [PMID: 36145375 PMCID: PMC9503898 DOI: 10.3390/ph15091155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 09/07/2022] [Accepted: 09/13/2022] [Indexed: 11/18/2022] Open
Abstract
Somatostatin receptor subtype 2 (SSTR2) has become an essential target for radionuclide therapy of neuroendocrine tumors (NETs). JR11 was introduced as a promising antagonist peptide to target SSTR2. However, due to its rapid blood clearance, a better pharmacokinetic profile is necessary for more effective treatment. Therefore, two JR11 analogs (8a and 8b), each carrying an albumin binding domain, were designed to prolong the blood residence time of JR11. Both compounds were labeled with lutetium-177 and evaluated via in vitro assays, followed by in vivo SPECT/CT imaging and ex vivo biodistribution studies. [177Lu]Lu-8a and [177Lu]Lu-8b were obtained with high radiochemical purity (>97%) and demonstrated excellent stability in PBS and mouse serum (>95%). [177Lu]Lu-8a showed better affinity towards human albumin compared to [177Lu]Lu-8b. Further, 8a and 8b exhibited binding affinities 30- and 48-fold lower, respectively, than that of the parent peptide JR11, along with high cell uptake and low internalization rate. SPECT/CT imaging verified high tumor accumulation for [177Lu]Lu-8a and [177Lu]Lu-JR11 at 4, 24, 48, and 72 h post-injection, but no tumor uptake was observed for [177Lu]Lu-8b. Ex vivo biodistribution studies revealed high and increasing tumor uptake for [177Lu]Lu-8a. However, its extended blood circulation led to an unfavorable biodistribution profile for radionuclide therapy.
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Affiliation(s)
- Sofia Koustoulidou
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Maryana Handula
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Corrina de Ridder
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Debra Stuurman
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Savanne Beekman
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Marion de Jong
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Julie Nonnekens
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
- Department of Molecular Genetics, Erasmus MC Cancer Institute, Erasmus University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Yann Seimbille
- Department of Radiology and Nuclear Medicine, Erasmus MC Cancer Institute, Erasmus University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
- Life Sciences Division, TRIUMF, Vancouver, BC V6T 2A3, Canada
- Correspondence: ; Tel.: +31-10-703-8961
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Refardt J, Hofland J, Wild D, Christ E. Molecular Imaging of Neuroendocrine Neoplasms. J Clin Endocrinol Metab 2022; 107:e2662-e2670. [PMID: 35380158 DOI: 10.1210/clinem/dgac207] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Indexed: 12/17/2022]
Abstract
The key for molecular imaging is the use of a radiotracer with a radioactive and a functional component. While the functional component targets a specific feature of the tumor, the radioactive component makes the target visible. Neuroendocrine neoplasms (NEN) are a diverse group of rare tumors that arise from neuroendocrine cells found mainly in the gastroenteropancreatic system, lung, thyroid, and adrenal glands. They are characterized by the expression of specific hormone receptors on the tumor cell surface, which makes them ideal targets for radiolabeled peptides. The most commonly expressed hormone receptors on NEN cells are the somatostatin receptors. They can be targeted for molecular imaging with various radiolabeled somatostatin analogs, but also with somatostatin antagonists, which have shown improved imaging quality. 18F-DOPA imaging has become a second-line imaging modality in NENs, with the exception of the evaluation of advanced medullary thyroid carcinoma. Alternatives for NENs with insufficient somatostatin receptor expression due to poor differentiation involve targeting glucose metabolism, which can also be used for prognosis. For the localization of the often-small insulinoma, glucagon-like peptide-1 (GLP-1) receptor imaging has become the new standard. Other alternatives involve metaiodobenzylguanidine and the molecular target C-X-C motif chemokine receptor-4. In addition, new radiopeptides targeting the fibroblast activation protein, the glucose-dependent insulinotropic polypeptide receptor and cholecystokinin-2 receptors have been identified in NENs and await further evaluation. This mini-review aims to provide an overview of the major molecular imaging modalities currently used in the field of NENs, and also to provide an outlook on future developments.
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Affiliation(s)
- Julie Refardt
- Department of Internal Medicine, Section of Endocrinology, ENETS Center of Excellence, Erasmus Medical Center, Rotterdam, the Netherlands
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, Basel, Switzerland
- Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, Basel, Switzerland
| | - Johannes Hofland
- Department of Internal Medicine, Section of Endocrinology, ENETS Center of Excellence, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Damian Wild
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, Basel, Switzerland
- Division of Nuclear Medicine, University Hospital Basel, Basel, Switzerland
| | - Emanuel Christ
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, Basel, Switzerland
- Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, Basel, Switzerland
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Christ E, Wild D, Refardt J. Molecular Imaging in neuroendocrine neoplasias. Presse Med 2022; 51:104115. [PMID: 35131317 DOI: 10.1016/j.lpm.2022.104115] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 01/11/2022] [Accepted: 01/28/2022] [Indexed: 12/16/2022] Open
Abstract
Molecular imaging, which uses molecular targets due to the overexpression of specific peptide hormone receptors on the tumour surface, has become an indispensable diagnostic technique. Neuroendocrine neoplasms (NENs) especially differentiated NENs or neuroendocrine tumours (NETs) are a rare group of heterogeneous tumours, characterized by the expression of hormone receptors on the tumour cell surface. This property makes them receptive to diagnostic and therapeutic approaches (theranostics) using radiolabelled peptides. Amongst the known hormone receptors, somatostatin receptors (SSTR) are expressed on the majority of NETs and are therefore the most relevant receptors for theranostic approaches. Current research aims to medically upregulate their expression, while other focuses are on the use of different radiopeptides (64Cu and 67Cu) or somatostatin-antagonists instead of the established somatostatin agonists. The GLP-1 receptor is another clinically relevant target, as GLP-1-R imaging has become the new standard for the localisation of insulinomas. For staging and prognostic evaluation in dedifferentiated NENs, 18F-FDG-imaging is useful, but lacks a therapeutic counterpart. Further options for patients with insufficient expression of SSTR involve metaiodobenzylguanidine (MIBG) and the molecular target C-X-C motif chemokine receptor-4 (CXCR4). New targets such as the glucose-dependant insulinotropic polypeptide receptor (GIPR) and the fibroblast activation protein (FAP) have been identified in NENs recently and await further evaluation. For medullary thyroid cancer 18-F-DOPA imaging is standard, however this technique is rather second line for other NENs. In this area, the discovery of minigastrin, which targets the cholecystokinin-2 (CCK2) receptors in medullary thyroid carcinoma and foregut NENs, may improve future management. This review aims to provide an overview of the most commonly used functional imaging modalities for theranostics in NENs today and in the possible future.
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Affiliation(s)
- Emanuel Christ
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, Basel, Switzerland; Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, Basel, Switzerland.
| | - Damian Wild
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, Basel, Switzerland; Division of Nuclear Medicine, University Hospital Basel, Basel, Switzerland
| | - Julie Refardt
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, Basel, Switzerland; Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, Basel, Switzerland
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Vahidfar N, Farzanehfar S, Abbasi M, Mirzaei S, Delpassand ES, Abbaspour F, Salehi Y, Biersack HJ, Ahmadzadehfar H. Diagnostic Value of Radiolabelled Somatostatin Analogues for Neuroendocrine Tumour Diagnosis: The Benefits and Drawbacks of [64Cu]Cu-DOTA-TOC. Cancers (Basel) 2022; 14:cancers14081914. [PMID: 35454822 PMCID: PMC9027354 DOI: 10.3390/cancers14081914] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/07/2022] [Accepted: 04/08/2022] [Indexed: 02/04/2023] Open
Abstract
Simple Summary One of the most incredible advances in nuclear medicine is early detection of neuroendocrine tumors, which leads to appropriate and expedient treatment pathways. Advances made with somatostatin analogue derivatives radiolabeled with Gallium-68 clarified the paths of diagnosis and treatment properly. Despite the significant improvements, widespread efforts are in progress to attain the most specific radiopharmaceutical for this purpose. In this literature review, we will provide a short overview on the role of nuclear medicine in the diagnosis of neuroendocrine tumors focusing on [64Cu]Cu-DOTA-TOC as a new radiopharmaceutical with promising clinical results. Abstract Neuroendocrine tumours (NETs) arise from secondary epithelial cell lines in the gastrointestinal or respiratory system organs. The rate of development of these tumours varies from an indolent to an aggressive course, typically being initially asymptomatic. The identification of these tumours is difficult, particularly because the primary tumour is often small and undetectable by conventional anatomical imaging. Consequently, diagnosis of NETs is complicated and has been a significant challenge until recently. In the last 30 years, the advent of novel nuclear medicine diagnostic procedures has led to a substantial increase in NET detection. Great varieties of exclusive single photon emission computed tomography (SPECT) and positron emission tomography (PET) radiopharmaceuticals for detecting NETs are being applied successfully in clinical settings, including [111In]In-pentetreotide, [99mTc]Tc-HYNIC-TOC/TATE, [68Ga]Ga-DOTA-TATE, and [64Cu]Cu-DOTA-TOC/TATE. Among these tracers for functional imaging, PET radiopharmaceuticals are clearly and substantially superior to planar or SPECT imaging radiopharmaceuticals. The main advantages include higher resolution, better sensitivity and increased lesion-to-background uptake. An advantage of diagnosis with a radiopharmaceutical is the capacity of theranostics to provide concomitant diagnosis and treatment with particulate radionuclides, such as beta and alpha emitters including Lutetium-177 (177Lu) and Actinium-225 (225Ac). Due to these unique challenges involved with diagnosing NETs, various PET tracers have been developed. This review compares the clinical characteristics of radiolabelled somatostatin analogues for NET diagnosis, focusing on the most recently FDA-approved [64Cu]Cu-DOTA-TATE as a state-of-the art NET-PET/CT radiopharmaceutical.
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Affiliation(s)
- Nasim Vahidfar
- Department of Nuclear Medicine, Vali-Asr Hospital, Tehran University of Medical Sciences, Tehran 1419733133, Iran; (N.V.); (S.F.); (M.A.); (Y.S.)
| | - Saeed Farzanehfar
- Department of Nuclear Medicine, Vali-Asr Hospital, Tehran University of Medical Sciences, Tehran 1419733133, Iran; (N.V.); (S.F.); (M.A.); (Y.S.)
| | - Mehrshad Abbasi
- Department of Nuclear Medicine, Vali-Asr Hospital, Tehran University of Medical Sciences, Tehran 1419733133, Iran; (N.V.); (S.F.); (M.A.); (Y.S.)
| | - Siroos Mirzaei
- Clinic Ottakring, Institute of Nuclear Medicine with PET-Center, 1220 Vienna, Austria;
| | - Ebrahim S. Delpassand
- RadioMedix, Inc., Houston, TX 77041, USA;
- Excel Diagnostics and Nuclear Oncology Center, Houston, TX 77042, USA
| | - Farzad Abbaspour
- Division of Nuclear Medicine, Department of Medicine, The Ottawa Hospital, University of Ottawa, Ottawa, ON K1H 8L6, Canada;
| | - Yalda Salehi
- Department of Nuclear Medicine, Vali-Asr Hospital, Tehran University of Medical Sciences, Tehran 1419733133, Iran; (N.V.); (S.F.); (M.A.); (Y.S.)
| | - Hans Jürgen Biersack
- Department of Nuclear Medicine, University Hospital Bonn, 53127 Bonn, Germany;
- Betaklinik Bonn, 53227 Bonn, Germany
| | - Hojjat Ahmadzadehfar
- Department of Nuclear Medicine, Klinikum Westfalen, 44309 Dortmund, Germany
- Correspondence:
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Hou G, Zhang Y, Liu Y, Wang P, Xia W, Xing X, Huo L, Li F, Jing H. Head-to-Head Comparison of 68Ga-DOTA-TATE and 68Ga-DOTA-JR11 PET/CT in Patients With Tumor-Induced Osteomalacia: A Prospective Study. Front Oncol 2022; 12:811209. [PMID: 35280786 PMCID: PMC8913035 DOI: 10.3389/fonc.2022.811209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 01/28/2022] [Indexed: 11/13/2022] Open
Abstract
Background The purpose of this study is to compare the sensitivity of 68Ga-DOTA-JR11 and 68Ga-DOTA-TATE PET/CT for detecting the responsible tumor of tumor-induced osteomalacia (TIO) and investigate if 68Ga-DOTA-JR11 PET/CT can identify the culprit tumor of TIO in multiple suspicious lesions in 68Ga-DOTA-TATE PET/CT. Methods A total of 19 patients with suspected TIO were prospectively recruited in this study. Each patient underwent whole-body PET/CT scan 40–60 min postinjection using 68Ga-DOTA-TATE and 68Ga-DOTA-JR11 on the same PET/CT, respectively in sequence, and on consecutive days. The diagnosis of TIO was confirmed by the combination of the postsurgical pathological results of the tumor and clinical information. Results Among the 19 patients with TIO who were included in this study, culprit tumors from all patients were confirmed pathologically. 68Ga-DOTA-TATE PET/CT positively identified the causative tumor in 18/19 patients, whereas 68Ga-DOTA-JR11 PET/CT was positive in 11/19 patients (94.7% vs. 57.9%, respectively; p < 0.05). 68Ga-DOTA-TATE PET/CT demonstrated more than one increased focal activity in 7 patients for a total of 16 lesions (3 lesions each in 2 patients and 2 lesions each in the rest 5 patients). However, seven of these 16 lesions showed concordant results on 68Ga-DOTA-JR11 PET/CT by demonstrating increased activity (one lesion in each of the 7 patients). The surgical specimens of the lesions in these 7 patients confirmed the phosphaturic mesenchymal tumor. A total of 11 culprit tumors were positive in both 68Ga-DOTA-TATE and 68Ga-DOTA-JR11 PET/CT. The SUVmax of 11 culprit tumors was significantly higher on 68Ga-DOTA-TATE PET/CT compared with that on 68Ga-DOTA-JR11 PET/CT (17.8 ± 12.5 vs. 6.8 ± 6.2; p < 0.05). Conclusions 68Ga-DOTA-TATE PET/CT is more sensitive to 68Ga-DOTA-JR11 PET/CT in the detection of the culprit tumor of TIO. However, 68Ga-DOTA-JR11 PET/CT might be helpful to identify the tumor in multiple suspicious lesions in 68Ga-DOTA-TATE PET/CT. Clinical Trial Registration clinicaltrials.gov, identifier NCT 04689893.
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Affiliation(s)
- Guozhu Hou
- Department of Nuclear Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.,Beijing Key Laboratory of Molecular Targeted Diagnosis and Therapy in Nuclear Medicine, Beijing, China
| | - Yuwei Zhang
- Department of Nuclear Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.,Beijing Key Laboratory of Molecular Targeted Diagnosis and Therapy in Nuclear Medicine, Beijing, China
| | - Yu Liu
- Department of Nuclear Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.,Beijing Key Laboratory of Molecular Targeted Diagnosis and Therapy in Nuclear Medicine, Beijing, China
| | - Peipei Wang
- Department of Nuclear Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.,Beijing Key Laboratory of Molecular Targeted Diagnosis and Therapy in Nuclear Medicine, Beijing, China
| | - Weibo Xia
- Department of Endocrinology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xiaoping Xing
- Department of Endocrinology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Li Huo
- Department of Nuclear Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.,Beijing Key Laboratory of Molecular Targeted Diagnosis and Therapy in Nuclear Medicine, Beijing, China
| | - Fang Li
- Department of Nuclear Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.,Beijing Key Laboratory of Molecular Targeted Diagnosis and Therapy in Nuclear Medicine, Beijing, China
| | - Hongli Jing
- Department of Nuclear Medicine, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.,Beijing Key Laboratory of Molecular Targeted Diagnosis and Therapy in Nuclear Medicine, Beijing, China
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68Ga-TP1580 as a novel molecular probe for HER2-positive tumor imaging using MicroPET. J Radioanal Nucl Chem 2022. [DOI: 10.1007/s10967-022-08236-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Fani M, Mansi R, Nicolas GP, Wild D. Radiolabeled Somatostatin Analogs-A Continuously Evolving Class of Radiopharmaceuticals. Cancers (Basel) 2022; 14:cancers14051172. [PMID: 35267479 PMCID: PMC8909681 DOI: 10.3390/cancers14051172] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 02/21/2022] [Accepted: 02/22/2022] [Indexed: 11/16/2022] Open
Abstract
Somatostatin receptors (SSTs) are recognized as favorable molecular targets in neuroendocrine tumors (NETs) and neuroendocrine neoplasms (NENs), with subtype 2 (SST2) being the predominantly and most frequently expressed. PET/CT imaging with 68Ga-labeled SST agonists, e.g., 68Ga-DOTA-TOC (SomaKit TOC®) or 68Ga-DOTA-TATE (NETSPOT®), plays an important role in staging and restaging these tumors and can identify patients who qualify and would potentially benefit from peptide receptor radionuclide therapy (PRRT) with the therapeutic counterparts 177Lu-DOTA-TOC or 177Lu-DOTA-TATE (Lutathera®). This is an important feature of SST targeting, as it allows a personalized treatment approach (theranostic approach). Today, new developments hold promise for enhancing diagnostic accuracy and therapeutic efficacy. Among them, the use of SST2 antagonists, such as JR11 and LM3, has shown certain advantages in improving image sensitivity and tumor radiation dose, and there is evidence that they may find application in other oncological indications beyond NETs and NENs. In addition, PRRT performed with more cytotoxic α-emitters, such as 225Ac, or β- and Auger electrons, such as 161Tb, presents higher efficacy. It remains to be seen if any of these new developments will overpower the established radiolabeled SST analogs and PRRT with β--emitters.
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Affiliation(s)
- Melpomeni Fani
- Division of Radiopharmaceutical Chemistry, University Hospital Basel, 4031 Basel, Switzerland;
- Correspondence:
| | - Rosalba Mansi
- Division of Radiopharmaceutical Chemistry, University Hospital Basel, 4031 Basel, Switzerland;
| | - Guillaume P. Nicolas
- Division of Nuclear Medicine, University Hospital Basel, 4031 Basel, Switzerland; (G.P.N.); (D.W.)
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, 4031 Basel, Switzerland
| | - Damian Wild
- Division of Nuclear Medicine, University Hospital Basel, 4031 Basel, Switzerland; (G.P.N.); (D.W.)
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, 4031 Basel, Switzerland
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PET imaging of pancreatic cancer. Nucl Med Mol Imaging 2022. [DOI: 10.1016/b978-0-12-822960-6.00207-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Maina T, Nock BA. Peptide radiopharmaceuticals for targeted diagnosis & therapy of human tumors. Nucl Med Mol Imaging 2022. [DOI: 10.1016/b978-0-12-822960-6.00078-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Peptide Receptor Radionuclide Therapy Targeting the Somatostatin Receptor: Basic Principles, Clinical Applications and Optimization Strategies. Cancers (Basel) 2021; 14:cancers14010129. [PMID: 35008293 PMCID: PMC8749814 DOI: 10.3390/cancers14010129] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/13/2021] [Accepted: 12/22/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary Peptide receptor radionuclide therapy (PRRT) is a systemic treatment consisting of the administration of a tumor-targeting radiopharmaceutical into the circulation of a patient. The radiopharmaceutical will bind to a specific peptide receptor leading to tumor-specific binding and retention. This will subsequently cause lethal DNA damage to the tumor cell. The only target that is currently used in widespread clinical practice is the somatostatin receptor, which is overexpressed on a range of tumor cells, including neuroendocrine tumors and neural-crest derived tumors. Academia played an important role in the development of PRRT, which has led to heterogeneous literature over the last two decades, as no standard radiopharmaceutical or regimen has been available for a long time. This review focuses on the basic principles and clinical applications of PRRT, and discusses several PRRT-optimization strategies. Abstract Peptide receptor radionuclide therapy (PRRT) consists of the administration of a tumor-targeting radiopharmaceutical into the circulation of a patient. The radiopharmaceutical will bind to a specific peptide receptor leading to tumor-specific binding and retention. The only target that is currently used in clinical practice is the somatostatin receptor (SSTR), which is overexpressed on a range of tumor cells, including neuroendocrine tumors and neural-crest derived tumors. Academia played an important role in the development of PRRT, which has led to heterogeneous literature over the last two decades, as no standard radiopharmaceutical or regimen has been available for a long time. This review provides a summary of the treatment efficacy (e.g., response rates and symptom-relief), impact on patient outcome and toxicity profile of PRRT performed with different generations of SSTR-targeting radiopharmaceuticals, including the landmark randomized-controlled trial NETTER-1. In addition, multiple optimization strategies for PRRT are discussed, i.e., the dose–effect concept, dosimetry, combination therapies (i.e., tandem/duo PRRT, chemoPRRT, targeted molecular therapy, somatostatin analogues and radiosensitizers), new radiopharmaceuticals (i.e., SSTR-antagonists, Evans-blue containing vector molecules and alpha-emitters), administration route (intra-arterial versus intravenous) and response prediction via molecular testing or imaging. The evolution and continuous refinement of PRRT resulted in many lessons for the future development of radionuclide therapy aimed at other targets and tumor types.
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Zhu W, Jia R, Yang Q, Cheng Y, Zhao H, Bai C, Xu J, Yao S, Huo L. A prospective randomized, double-blind study to evaluate the diagnostic efficacy of 68Ga-NODAGA-LM3 and 68Ga-DOTA-LM3 in patients with well-differentiated neuroendocrine tumors: compared with 68Ga-DOTATATE. Eur J Nucl Med Mol Imaging 2021; 49:1613-1622. [PMID: 34874478 DOI: 10.1007/s00259-021-05512-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 07/27/2021] [Indexed: 01/18/2023]
Abstract
PURPOSE The purpose of this study is to evaluate the diagnostic efficacy of 68 Ga-NODAGA-LM3 and 68 Ga-DOTA-LM3 and compare them with 68 Ga-DOTATATE in patients with well-differentiated neuroendocrine tumors. METHODS Patients were prospectively recruited and equally randomized into two arms: Arm A, patients would undergo a whole-body 68 Ga-NODAGA-LM3 PET/CT scan on the 1st day and 68 Ga-DOTATATE PET/CT scan on the 2nd day; Arm B, patients would undergo a whole-body 68 Ga-DOTA-LM3 PET/CT scan on the 1st day and 68 Ga-DOTATATE PET/CT scan on the 2nd day. Biodistribution in normal organs, lesion detection ability, and tumor uptake were compared between antagonist and agonist in each arm. RESULTS A total of 40 patients with well-differentiated NETs, 20 in each arm, were recruited in the study. 68 Ga-NODAGA-LM3 showed a similar pattern as 68 Ga-DOTATATE, while 68 Ga-DOTA-LM3 demonstrated significantly lower uptake in almost all normal organs compared to 68 Ga-DOTATATE. Both 68 Ga-NODAGA-LM3 and 68 Ga-DOTA-LM3 showed superiority in lesion detection compared to 68 Ga-DOTATATE on lesion-based and patient-based comparison. 68 Ga-NODAGA-LM3 showed a significantly higher tumor uptake (median SUVmax 29.1 versus 21.6, P < 0.05) and tumor-to-background ratio (median tumor-to-liver ratio 5.0 versus 2.9, P < 0.05) compared to 68 Ga-DOTATATE. 68 Ga-DOTA-LM3 showed comparable uptake (median SUVmax 16.1 versus 17.8, P = 0.714) and higher tumor-to-background ratio (median tumor-to-liver ratio 5.2 versus 2.1, P < 0.05). CONCLUSION Both 68 Ga-NODAGA-LM3 and 68 Ga-DOTA-LM3 are promising SSTR2 antagonists for neuroendocrine tumors. They demonstrated superiority in diagnostic efficacy compared to agonist 68 Ga-DOTATATE. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT04318561.
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Affiliation(s)
- Wenjia Zhu
- Department of Nuclear Medicine, Beijing Key Laboratory of Molecular Targeted Diagnosis and Therapy in Nuclear Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Shuaifuyuan, Dongcheng District, Beijing, 100730, China
| | - Ru Jia
- Department of Gastrointestinal Oncology, the Fifth Medical Center, General Hospital of PLA, No. 8, East Avenue, Fengtai District, Beijing, China
| | - Qiao Yang
- Department of Nuclear Medicine, Beijing Key Laboratory of Molecular Targeted Diagnosis and Therapy in Nuclear Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Shuaifuyuan, Dongcheng District, Beijing, 100730, China
| | - Yuejuan Cheng
- Department of Oncology, Peking Union Medical College Hospital, Beijing, 100730, China
| | - Hong Zhao
- Department of Hepatobiliary Surgery, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100021, China
| | - Chunmei Bai
- Department of Oncology, Peking Union Medical College Hospital, Beijing, 100730, China
| | - Jianming Xu
- Department of Gastrointestinal Oncology, the Fifth Medical Center, General Hospital of PLA, No. 8, East Avenue, Fengtai District, Beijing, China
| | - Shaobo Yao
- Department Nuclear Medicine, The First Affiliated Hospital of Fujian Medical University, Fuzhou, 350005, Fujian, China
| | - Li Huo
- Department of Nuclear Medicine, Beijing Key Laboratory of Molecular Targeted Diagnosis and Therapy in Nuclear Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Shuaifuyuan, Dongcheng District, Beijing, 100730, China.
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Haider A, Bengs S, Gebhard C. Imaging inflammation in atherosclerosis: Exploring all avenues. J Nucl Cardiol 2021; 28:2514-2517. [PMID: 32236840 DOI: 10.1007/s12350-020-02103-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Accepted: 03/09/2020] [Indexed: 02/07/2023]
Affiliation(s)
- Ahmed Haider
- Department of Nuclear Medicine, University Hospital Zurich, Raemistrasse 100, 8091, Zurich, Switzerland
- Center for Molecular Cardiology, University of Zurich, 8952, Schlieren, Switzerland
| | - Susan Bengs
- Department of Nuclear Medicine, University Hospital Zurich, Raemistrasse 100, 8091, Zurich, Switzerland
- Center for Molecular Cardiology, University of Zurich, 8952, Schlieren, Switzerland
| | - Catherine Gebhard
- Department of Nuclear Medicine, University Hospital Zurich, Raemistrasse 100, 8091, Zurich, Switzerland.
- Center for Molecular Cardiology, University of Zurich, 8952, Schlieren, Switzerland.
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Meester EJ, Krenning BJ, de Blois E, de Jong M, van der Steen AFW, Bernsen MR, van der Heiden K. Imaging inflammation in atherosclerotic plaques, targeting SST 2 with [ 111In]In-DOTA-JR11. J Nucl Cardiol 2021; 28:2506-2513. [PMID: 32026330 PMCID: PMC8709817 DOI: 10.1007/s12350-020-02046-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 12/24/2019] [Indexed: 12/26/2022]
Abstract
BACKGROUND Imaging Somatostatin Subtype Receptor 2 (SST2) expressing macrophages by [DOTA,Tyr3]-octreotate (DOTATATE) has proven successful for plaque detection. DOTA-JR11 is a SST2 targeting ligand with a five times higher tumor uptake than DOTATATE, and holds promise to improve plaque imaging. The aim of this study was to evaluate the potential of DOTA-JR11 for plaque detection. METHODS AND RESULTS Atherosclerotic ApoE-/- mice (n = 22) fed an atherogenic diet were imaged by SPECT/CT two hours post injection of [111In]In-DOTA-JR11 (~ 200 pmol, ~ 50 MBq). In vivo plaque uptake of [111In]In-DOTA-JR11 was visible in all mice, with a target-to-background-ratio (TBR) of 2.23 ± 0.35. Post-mortem scans after thymectomy and ex vivo scans of the arteries after excision of the arteries confirmed plaque uptake of the radioligand with TBRs of 2.46 ± 0.52 and 3.43 ± 1.45 respectively. Oil red O lipid-staining and ex vivo autoradiography of excised arteries showed [111In]In-DOTA-JR11 uptake at plaque locations. Histological processing showed CD68 (macrophages) and SST2 expressing cells in plaques. SPECT/CT, in vitro autoradiography and immunohistochemistry performed on slices of a human carotid endarterectomy sample showed [111In]In-DOTA-JR11 uptake at plaque locations containing CD68 and SST2 expressing cells. CONCLUSIONS The results of this study indicate DOTA-JR11 as a promising ligand for visualization of atherosclerotic plaque inflammation.
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Affiliation(s)
- Eric J Meester
- Department of Biomedical Engineering, Thorax Center, Erasmus Medical Center, PO Box 2040, 3000 CA, Rotterdam, The Netherlands
- Department of Radiology & Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | | | - Erik de Blois
- Department of Radiology & Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Marion de Jong
- Department of Radiology & Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Antonius F W van der Steen
- Department of Biomedical Engineering, Thorax Center, Erasmus Medical Center, PO Box 2040, 3000 CA, Rotterdam, The Netherlands
| | - Monique R Bernsen
- Department of Radiology & Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Kim van der Heiden
- Department of Biomedical Engineering, Thorax Center, Erasmus Medical Center, PO Box 2040, 3000 CA, Rotterdam, The Netherlands.
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Refardt J, Hofland J, Wild D, Christ E. New Directions in Imaging Neuroendocrine Neoplasms. Curr Oncol Rep 2021; 23:143. [PMID: 34735669 PMCID: PMC8568754 DOI: 10.1007/s11912-021-01139-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/05/2021] [Indexed: 12/14/2022]
Abstract
Purpose of Review Accurate imaging is crucial for correct diagnosis, staging, and therapy of neuroendocrine neoplasms (NENs). The search for the optimal imaging technique has triggered rapid development in the field. This review aims at giving an overview on contemporary imaging methods and providing an outlook on current progresses. Recent Findings The discovery of molecular targets due to the overexpression of specific peptide hormone receptors on the NEN’s surface has triggered the development of multiple radionuclide imaging modalities. In addition to the established imaging technique of targeting somatostatin receptors, several alternative radioligands have been developed. Targeting the glucagon-like peptide-1 receptor by exendin-4 has a high sensitivity in localizing insulinomas. For dedifferentiated NENs, new molecular targets such as the C-X-C motif chemokine-receptor-4 have been evaluated. Other new targets involve the fibroblast activation protein and the cholecystokinin-2 receptors, where the ligand minigastrin opens new possibilities for the management of medullary thyroid carcinoma. Summary Molecular imaging is an emerging field that improves the management of NENs.
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Affiliation(s)
- Julie Refardt
- Department of Internal Medicine, Section of Endocrinology, ENETS Center of Excellence, Erasmus Medical Center, Rotterdam, the Netherlands.,ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, Petersgraben 4, 4031, Basel, Switzerland.,Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, Petersgraben 4, 4031, Basel, Switzerland
| | - Johannes Hofland
- Department of Internal Medicine, Section of Endocrinology, ENETS Center of Excellence, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Damian Wild
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, Petersgraben 4, 4031, Basel, Switzerland.,Division of Nuclear Medicine, University Hospital Basel, Petersgraben 4, 4031, Basel, Switzerland
| | - Emanuel Christ
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, Petersgraben 4, 4031, Basel, Switzerland. .,Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, Petersgraben 4, 4031, Basel, Switzerland.
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Long T, Hou J, Yang N, Zhou M, Li Y, Li J, Tang Y, Chen D, Hu S. Utility of 18F-AlF-NOTA-Octreotide PET/CT in the Localization of Tumor-Induced Osteomalacia. J Clin Endocrinol Metab 2021; 106:e4202-e4209. [PMID: 33864458 DOI: 10.1210/clinem/dgab258] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Indexed: 11/19/2022]
Abstract
CONTEXT Tumor-induced osteomalacia (TIO) is a paraneoplastic disorder, usually caused by benign mesenchymal tumors that produce high levels of fibroblast growth factor 23. The only curative therapy is resection of the causative tumors. OBJECTIVE This research was conducted to evaluate the efficacy of 18F-AlF-NOTA-octreotide (18F-OC) positron emission tomography/computed tomography (PET/CT) in detecting TIO and its impact on patient management. METHODS Retrospective analysis was conducted of 17 patients with hypophosphatemic osteomalacia suspected to be TIO. A 18F-OC PET/CT study was performed in all 17 patients to localize the tumor and 68Ga-DOTATATE PET/CT was performed in 4 out of 17 patients; both studies were performed within 1 week of each other. Both studies were interpreted blindly without the knowledge of other imaging findings. The image findings were compared with the results of histopathological examinations and clinical follow-ups. RESULTS The 18F-OC PET/CT scans were positive in 14 patients. Furthermore, 4 of 14 patients were scanned with both 18F-OC and 68Ga-DOTATATE PET/CT. Both studies were able to localize the tumor in all 4 patients. In total, 14 patients had surgery to remove the lesions. Postsurgical pathological examination confirmed causative tumors in these patients, whose symptoms diminished promptly. Serum phosphate levels normalized, confirming the diagnosis of TIO. 18F-OC PET/CT sensitivity, specificity, and accuracy were 87.5%, 100%, and 88.2% respectively. 18F-OC PET/CT findings affected patient management in 88.2% of cases. CONCLUSION 18F-OC PET/CT scan is useful in the detection of tumors causing TIO. Further studies with larger patient populations are needed to validate the result.
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Affiliation(s)
- Tingting Long
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Jiale Hou
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Nengan Yang
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Ming Zhou
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Yulai Li
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Jian Li
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Yongxiang Tang
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Dengming Chen
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Shuo Hu
- Department of Nuclear Medicine, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
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Refardt J, Hofland J, Kwadwo A, Nicolas GP, Rottenburger C, Fani M, Wild D, Christ E. Theranostics in neuroendocrine tumors: an overview of current approaches and future challenges. Rev Endocr Metab Disord 2021; 22:581-594. [PMID: 32495250 DOI: 10.1007/s11154-020-09552-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Neuroendocrine neoplasms (NENs) comprise a heterogeneous group of tumors, mainly localized in the gastrointestinal system. What characterizes NENs is the expression of hormone receptors on the tumor cell surface, making them accessible for diagnostic and therapeutic approaches (theranostics) using radiolabelled peptides. Somatostatin receptors subtype-two (SST2) play an important role in NENs since they are overexpressed and homogeneously distributed at the surface of the majority of NENs. Accordingly, targeting SST2 for diagnostic and therapeutic purposes has been established. Current research aims at upregulating its expression by epigenetic treatment or improving its targeting via use of alternative radioligands. In addition, recent data suggest a future role of SST antagonists as a diagnostic tool and a potential therapeutic option. Another promising target is the glucagon-like peptide-1 (GLP-1) receptor. Targeting GLP-1R using exendin-4 (GLP-1 analogue) has a high sensitivity for the localization of the often SST2-negative sporadic insulinomas and insulinomas in the context of multiple endocrine neoplasia type-1. Further options for patients with insufficient expression of SST2 involve metaiodobenzylguanidine (MIBG) and the molecular target C-X-C motif chemokine receptor-4 (CXCR4), which have been evaluated for potential theranostic approach in symptomatic NENs or dedifferentiated tumors. Recently, new targets such as the glucose-dependent insulinotropic polypeptide receptor (GIPR) and the fibroblast activation protein (FAP) have been identified in NENs. Finally, minigastrin - a ligand targeting the cholecystokinin-2 (CCK2) receptors in medullary thyroid carcinoma and foregut neuroendocrine tumors - may improve future management of these diseases with currently limited therapeutic options. This review summarises the current approaches and future challenges of diagnostic and therapeutic evaluations in neuroendocrine neoplasms.
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Affiliation(s)
- Julie Refardt
- Department of Internal Medicine, Section of Endocrinology, ENETS Center of Excellence, Erasmus Medical Center, Rotterdam, the Netherlands
- Department of Clinical Research, University of Basel, Basel, Switzerland
| | - Johannes Hofland
- Department of Internal Medicine, Section of Endocrinology, ENETS Center of Excellence, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Antwi Kwadwo
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, Basel, Switzerland
- Division of Nuclear Medicine, University Hospital Basel, Basel, Switzerland
| | - Guillaume P Nicolas
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, Basel, Switzerland
- Division of Nuclear Medicine, University Hospital Basel, Basel, Switzerland
| | - Christof Rottenburger
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, Basel, Switzerland
- Division of Nuclear Medicine, University Hospital Basel, Basel, Switzerland
| | - Melpomeni Fani
- Division of Radiopharmaceutical Chemistry, University Hospital Basel, Basel, Switzerland
| | - Damian Wild
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, Basel, Switzerland
- Division of Nuclear Medicine, University Hospital Basel, Basel, Switzerland
| | - Emanuel Christ
- ENETS Center of Excellence for Neuroendocrine and Endocrine Tumors, University Hospital Basel, Basel, Switzerland.
- Department of Endocrinology, Diabetology and Metabolism, University Hospital Basel, Basel, Switzerland.
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Sneddon D, Cornelissen B. Emerging chelators for nuclear imaging. Curr Opin Chem Biol 2021; 63:152-162. [PMID: 34051509 DOI: 10.1016/j.cbpa.2021.03.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 02/28/2021] [Accepted: 03/09/2021] [Indexed: 11/25/2022]
Abstract
Chelators are necessary in nuclear medicine imaging to direct an inorganic radionuclide, a radiometal, to a desired target; unfortunately, there is no 'one-size-fits-all' chelator. As the toolbox of radiometals is expanding, new chelators are required to prevent off-target side effects. 1,4,7,10-Tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) is the current gold standard chelator for several radiometals, but typically, chelation requires harsh conditions, making it unsuitable to label biological vectors. The ideal chelator would allow labelling under mild conditions (near-neutral pH and low temperatures [∼37 °C]) and be both thermodynamically and kinetically stable. Over the past 2-3 years, several exciting chelators have been developed that have superior properties to make them worth investigating for future clinical applications.
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Affiliation(s)
- Deborah Sneddon
- MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, OX3 7LE, United Kingdom.
| | - Bart Cornelissen
- MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, OX3 7LE, United Kingdom
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Chastel A, Vimont D, Claverol S, Zerna M, Bodin S, Berndt M, Chaignepain S, Hindié E, Morgat C. 68Ga-Radiolabeling and Pharmacological Characterization of a Kit-Based Formulation of the Gastrin-Releasing Peptide Receptor (GRP-R) Antagonist RM2 for Convenient Preparation of [ 68Ga]Ga-RM2. Pharmaceutics 2021; 13:pharmaceutics13081160. [PMID: 34452121 PMCID: PMC8398231 DOI: 10.3390/pharmaceutics13081160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 07/13/2021] [Accepted: 07/22/2021] [Indexed: 12/17/2022] Open
Abstract
Background: [68Ga]Ga-RM2 is a potent Gastrin-Releasing Peptide-receptor (GRP-R) antagonist for imaging prostate cancer and breast cancer, currently under clinical evaluation in several specialized centers around the world. Targeted radionuclide therapy of GRP-R-expressing tumors is also being investigated. We here report the characteristics of a kit-based formulation of RM2 that should ease the development of GRP-R imaging and make it available to more institutions and patients. Methods: Stability of the investigated kits over one year was determined using LC/MS/MS and UV-HPLC. Direct 68Ga-radiolabeling was optimized with respect to buffer (pH), temperature, reaction time and shaking time. Conventionally prepared [68Ga]Ga-RM2 using an automated synthesizer was used as a comparator. Finally, the [68Ga]Ga-RM2 product was assessed with regards to hydrophilicity, affinity, internalization, membrane bound fraction, calcium mobilization assay and efflux, which is a valuable addition to the in vivo literature. Results: The kit-based formulation, kept between 2 °C and 8 °C, was stable for over one year. Using acetate buffer pH 3.0 in 2.5–5.1 mL total volume, heating at 100 °C during 10 min and cooling down for 5 min, the [68Ga]Ga-RM2 produced by kit complies with the requirements of the European Pharmacopoeia. Compared with the module production route, the [68Ga]Ga-RM2 produced by kit was faster, displayed higher yields, higher volumetric activity and was devoid of ethanol. In in vitro evaluations, the [68Ga]Ga-RM2 displayed sub-nanomolar affinity (Kd = 0.25 ± 0.19 nM), receptor specific and time dependent membrane-bound fraction of 42.0 ± 5.1% at 60 min and GRP-R mediated internalization of 24.4 ± 4.3% at 30 min. The [natGa]Ga-RM2 was ineffective in stimulating intracellular calcium mobilization. Finally, the efflux of the internalized activity was 64.3 ± 6.5% at 5 min. Conclusion: The kit-based formulation of RM2 is suitable to disseminate GRP-R imaging and therapy to distant hospitals without complex radiochemistry equipment.
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Affiliation(s)
- Adrien Chastel
- INCIA, University of Bordeaux, CNRS, EPHE, UMR 5287, F-33000 Bordeaux, France; (A.C.); (D.V.); (S.B.); (E.H.)
- Nuclear Medicine Department, University Hospital of Bordeaux, F-33000 Bordeaux, France
| | - Delphine Vimont
- INCIA, University of Bordeaux, CNRS, EPHE, UMR 5287, F-33000 Bordeaux, France; (A.C.); (D.V.); (S.B.); (E.H.)
| | - Stephane Claverol
- Proteome Platform, University Bordeaux, F-33000 Bordeaux, France; (S.C.); (S.C.)
| | - Marion Zerna
- Life Molecular Imaging (Formely Piramal Imaging) GmbH, 13353 Berlin, Germany; (M.Z.); (M.B.)
| | - Sacha Bodin
- INCIA, University of Bordeaux, CNRS, EPHE, UMR 5287, F-33000 Bordeaux, France; (A.C.); (D.V.); (S.B.); (E.H.)
- Nuclear Medicine Department, University Hospital of Bordeaux, F-33000 Bordeaux, France
| | - Mathias Berndt
- Life Molecular Imaging (Formely Piramal Imaging) GmbH, 13353 Berlin, Germany; (M.Z.); (M.B.)
| | - Stéphane Chaignepain
- Proteome Platform, University Bordeaux, F-33000 Bordeaux, France; (S.C.); (S.C.)
| | - Elif Hindié
- INCIA, University of Bordeaux, CNRS, EPHE, UMR 5287, F-33000 Bordeaux, France; (A.C.); (D.V.); (S.B.); (E.H.)
- Nuclear Medicine Department, University Hospital of Bordeaux, F-33000 Bordeaux, France
| | - Clément Morgat
- INCIA, University of Bordeaux, CNRS, EPHE, UMR 5287, F-33000 Bordeaux, France; (A.C.); (D.V.); (S.B.); (E.H.)
- Nuclear Medicine Department, University Hospital of Bordeaux, F-33000 Bordeaux, France
- Correspondence:
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Virgolini I, Bahri S, Kjaer A, Gronbaek H, Iversen P, Carlsen EA, Loft M, Knigge U, Maffey-Steffan J, Powell C, Miller CG, Rohban T, McEwan S, Czernin J. A randomised, factorial phase II study to determine the optimal dosing regimen for 68Ga-satoreotide trizoxetan as an imaging agent in patients with gastroenteropancreatic neuroendocrine tumours. J Nucl Med 2021; 63:376-383. [PMID: 34215673 PMCID: PMC8978200 DOI: 10.2967/jnumed.121.261936] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 06/07/2021] [Indexed: 11/16/2022] Open
Abstract
68Ga-satoreotide trizoxetan is a novel somatostatin receptor antagonist associated with high sensitivity and reproducibility in neuroendocrine tumour (NET) detection and localisation. However, the optimal peptide mass and radioactivity ranges for 68Ga-satoreotide trizoxetan have not yet been established. We therefore aimed to determine its optimal dosing regimen in patients with metastatic gastroenteropancreatic NETs in a prospective, randomised, 2×3 factorial, multicentre, phase II study. Methods: Patients received 68Ga-satoreotide trizoxetan at a peptide mass of 5-20 µg on day 1 of the study and of 30-45 µg on day 16-22, at one of three gallium-68 radioactivity ranges (40-80, 100-140, or 160-200 MBq). Whole-body PET/CT imaging was performed 50-70 minutes after each injection. The primary endpoint was the detection rate of NET lesions imaged by 68Ga-satoreotide trizoxetan relative to contrast-enhanced CT (CECT) (for each of the six peptide mass/radioactivity range combinations). Results: Twenty-four patients were evaluated in the per-protocol analysis. The median number of lesions detected by 68Ga-satoreotide trizoxetan PET/CT or PET only was at least twice as high as the number of lesions detected by CECT across the six studied peptide mass dose/radioactivity range combinations. There were no differences between the two peptide mass ranges and between the three radioactivity ranges in the number of identified lesions. However, a trend towards a lower relative lesion count was noted in the liver for the 40-80 MBq range. No relationship was observed between the radioactivity range per patient's body weight (MBq/kg) and the number of lesions detected by 68Ga-satoreotide trizoxetan. Median diagnostic sensitivity of 68Ga-satoreotide trizoxetan PET/CT, based on the number of lesions per patient, ranged from 85% to 87% across the different peptide mass and radioactivity ranges. Almost all reported adverse events were mild and self-limiting. Conclusion: A radioactivity of 100-200 MBq with a peptide mass up to 50 μg were confirmed as the optimal dosing regimen for 68Ga-satoreotide trizoxetan to be used in future phase III studies.
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Affiliation(s)
- Irene Virgolini
- Department of Nuclear Medicine, University of Innsbruck, Austria
| | - Shadfar Bahri
- Ahmanson Translational Theranostics Division, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, UCLA, United States
| | - Andreas Kjaer
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Department of Biomedical Sciences, Rigshospitalet, University of Copenhagen
| | - Henning Gronbaek
- Department of Hepatology & Gastroenterology, Aarhus University Hospital
| | - Peter Iversen
- Department of Nuclear Medicine and PET Center, Aarhus University Hospital, Denmark
| | - Esben Andreas Carlsen
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Department of Biomedical Sciences, Rigshospitalet, University of Copenhagen
| | - Mathias Loft
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Department of Biomedical Sciences, Rigshospitalet, University of Copenhagen
| | - Ulrich Knigge
- Department of Endocrinology PE and Department of Surgery C, Rigshospitalet, University of Copenhagen, Denmark
| | | | | | | | | | | | - Johannes Czernin
- Ahmanson Translational Theranostics Division, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, UCLA, United States
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Simultaneous Visualization of 161Tb- and 177Lu-Labeled Somatostatin Analogues Using Dual-Isotope SPECT Imaging. Pharmaceutics 2021; 13:pharmaceutics13040536. [PMID: 33921467 PMCID: PMC8070648 DOI: 10.3390/pharmaceutics13040536] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/29/2021] [Accepted: 04/07/2021] [Indexed: 11/17/2022] Open
Abstract
The decay of terbium-161 results in the emission of β¯-particles as well as conversion and Auger electrons, which makes terbium-161 interesting for therapeutic purposes. The aim of this study was to use dual-isotope SPECT imaging in order to demonstrate visually that terbium-161 and lutetium-177 are interchangeable without compromising the pharmacokinetic profile of the radiopharmaceutical. The 161Tb- and 177Lu-labeled somatostatin (SST) analogues DOTATOC (agonist) and DOTA-LM3 (antagonist) were tested in vitro to demonstrate equal properties regarding distribution coefficients and cell uptake into SST receptor-positive AR42J tumor cells. The radiopeptides were further investigated in AR42J tumor-bearing nude mice using the method of dual-isotope (terbium-161/lutetium-177) SPECT/CT imaging to enable the visualization of their distribution profiles in the same animal. Equal pharmacokinetic profiles were demonstrated for either of the two peptides, irrespective of whether it was labeled with terbium-161 or lutetium-177. Moreover, the visualization of the sub-organ distribution confirmed similar behavior of 161Tb- and 177Lu-labeled SST analogues. The data were verified in quantitative biodistribution studies using either type of peptide labeled with terbium-161 or lutetium-177. While the radionuclide did not have an impact on the organ distribution, this study confirmed previous data of a considerably higher tumor uptake of radiolabeled DOTA-LM3 as compared to the radiolabeled DOTATOC.
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SPECT Imaging of SST2-Expressing Tumors with 99mTc-Based Somatostatin Receptor Antagonists: The Role of Tetraamine, HYNIC, and Spacers. Pharmaceuticals (Basel) 2021; 14:ph14040300. [PMID: 33800582 PMCID: PMC8065591 DOI: 10.3390/ph14040300] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 03/24/2021] [Accepted: 03/25/2021] [Indexed: 12/24/2022] Open
Abstract
[99mTc]Tc-HYNIC-TOC is the most widely used 99mTc-labeled somatostatin receptor (SST) agonist for the SPECT imaging of SST-expressing tumors, such as neuroendocrine tumors. Recently, radiolabeled SST antagonists have shown improved diagnostic efficacy over agonists. 99mTc-labeled SST antagonists are lacking in clinical practice. Surprisingly, when [99mTc]Tc-HYNIC was conjugated to the SST2 antagonist SS01, SST2 imaging was not feasible. This was not the case when [99mTc]Tc-N4 was conjugated to SS01. Here, we assessed the introduction of different spacers (X: β-Ala, Ahx, Aun and PEG4) among HYNIC and SS01 with the aim of restoring the affinity of HYNIC conjugates. In addition, we used the alternative antagonist JR11 for determining the suitability of HYNIC with 99mTc-labeled SST2 antagonists. We performed a head-to-head comparison of the N4 conjugates of SS01 and JR11. [99mTc]Tc-HYNIC-TOC was used as a reference, and HEK-SST2 cells were used for in vitro and in vivo evaluation. EDDA was used as a co-ligand for all [99mTc]Tc-HYNIC conjugates. The introduction of Ahx restored, to a great extent, the SST2-mediated cellular uptake of the [99mTc]Tc-HYNIC-X conjugates (X: spacer), albeit lower than the corresponding [99mTc]Tc-N4-conjugates. SPECT/CT images showed that all 99mTc-labeled conjugates accumulated in the tumor and kidneys with [99mTc]Tc-HYNIC-PEG4-SS01, [99mTc]Tc-N4-SS01 and [99mTc]Tc-N4-JR11 having notably higher kidney uptake. Biodistribution studies showed similar or better tumor-to-non-tumor ratios for the [99mTc]Tc-HYNIC-Ahx conjugates, compared to the [99mTc]Tc-N4 counterparts. The [99mTc]Tc-HYNIC-Ahx conjugates of SS01 and JR11 were comparable to [99mTc]Tc-HYNIC-TOC as imaging agents. HYNIC is a suitable chelator for the development of 99mTc-labeled SST2 antagonists when a spacer of appropriate length, such as Ahx, is used.
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Meester EJ, de Blois E, Krenning BJ, van der Steen AFW, Norenberg JP, van Gaalen K, Bernsen MR, de Jong M, van der Heiden K. Autoradiographical assessment of inflammation-targeting radioligands for atherosclerosis imaging: potential for plaque phenotype identification. EJNMMI Res 2021; 11:27. [PMID: 33730311 PMCID: PMC7969682 DOI: 10.1186/s13550-021-00772-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 03/05/2021] [Indexed: 12/26/2022] Open
Abstract
PURPOSE Many radioligands have been developed for the visualization of atherosclerosis by targeting inflammation. However, interpretation of in vivo signals is often limited to plaque identification. We evaluated binding of some promising radioligands in an in vitro approach in atherosclerotic plaques with different phenotypes. METHODS Tissue sections of carotid endarterectomy tissue were characterized as early plaque, fibro-calcific plaque, or phenotypically vulnerable plaque. In vitro binding assays for the radioligands [111In]In-DOTATATE; [111In]In-DOTA-JR11; [67Ga]Ga-Pentixafor; [111In]In-DANBIRT; and [111In]In-EC0800 were conducted, the expression of the radioligand targets was assessed via immunohistochemistry. Radioligand binding and expression of radioligand targets was investigated and compared. RESULTS In sections characterized as vulnerable plaque, binding was highest for [111In]In-EC0800; followed by [111In]In-DANBIRT; [67Ga]Ga-Pentixafor; [111In]In-DOTA-JR11; and [111In]In-DOTATATE (0.064 ± 0.036; 0.052 ± 0.029; 0.011 ± 0.003; 0.0066 ± 0.0021; 0.00064 ± 0.00014 %Added activity/mm2, respectively). Binding of [111In]In-DANBIRT and [111In]In-EC0800 was highest across plaque phenotypes, binding of [111In]In-DOTA-JR11 and [67Ga]Ga-Pentixafor differed most between plaque phenotypes. Binding of [111In]In-DOTATATE was the lowest across plaque phenotypes. The areas positive for cells expressing the radioligand's target differed between plaque phenotypes for all targets, with lowest percentage area of expression in early plaque sections and highest in phenotypically vulnerable plaque sections. CONCLUSIONS Radioligands targeting inflammatory cell markers showed different levels of binding in atherosclerotic plaques and among plaque phenotypes. Different radioligands might be used for plaque detection and discerning early from vulnerable plaque. [111In]In-EC0800 and [111In]In-DANBIRT appear most suitable for plaque detection, while [67Ga]Ga-Pentixafor and [111In]In-DOTA-JR11 might be best suited for differentiation between plaque phenotypes.
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Affiliation(s)
- Eric J Meester
- Department of Biomedical Engineering, Thorax Center, Erasmus Medical Center, PO Box 2040, 3000 CA, Rotterdam, The Netherlands
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Erik de Blois
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | | | - Antonius F W van der Steen
- Department of Biomedical Engineering, Thorax Center, Erasmus Medical Center, PO Box 2040, 3000 CA, Rotterdam, The Netherlands
| | - Jeff P Norenberg
- Radiopharmaceutical Sciences, University of New Mexico, Albuquerque, NM, USA
| | - Kim van Gaalen
- Department of Biomedical Engineering, Thorax Center, Erasmus Medical Center, PO Box 2040, 3000 CA, Rotterdam, The Netherlands
| | - Monique R Bernsen
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Marion de Jong
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Kim van der Heiden
- Department of Biomedical Engineering, Thorax Center, Erasmus Medical Center, PO Box 2040, 3000 CA, Rotterdam, The Netherlands.
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Baum RP, Zhang J, Schuchardt C, Mueller D, Maecke H. First-in-human study of novel SSTR antagonist 177Lu-DOTA-LM3 for peptide receptor radionuclide therapy in patients with metastatic neuroendocrine neoplasms: dosimetry, safety and efficacy. J Nucl Med 2021; 62:1571-1581. [PMID: 33674401 DOI: 10.2967/jnumed.120.258889] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 02/16/2020] [Indexed: 12/24/2022] Open
Abstract
The objective of this study was to assess the safety, dosimetry, and efficacy of the 177Lu-labeled somatostatin receptor (SSTR) antagonist DOTA-p-Cl-Phe-cyclo (D-Cys-Tyr-D-4-amino-Phe(carbamoyl)-Lys-Thr-Cys)D-Tyr-NH2 (177Lu-DOTA-LM3) in patients with metastatic neuroendocrine neoplasms (NENs). Methods: Fifty-one patients (age 27-76, mean 51.6±13.9 years) with metastatic NENs underwent peptide receptor radionuclide therapy (PRRT) with 177Lu-DOTA-LM3 between August 2017 and December 2019. The median administered activity per cycle was 6.1±0.88 GBq (range 2.8-7.4 GBq). 68Ga-NODAGA-LM3 PET/CT was used for patient selection and follow-up after 177Lu-DOTA-LM3 PRRT. Morphologic and molecular responses were evaluated in accordance with RECIST 1.1 and European Organization for Research and Treatment of Cancer (EORTC) criteria. Treatment-related adverse events were graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events, version 5.0. Dosimetry was performed in 11 patients and compared with the SSTR agonist 177Lu-DOTATOC in 247 patients undergoing PRRT on the same dosimetry protocol. Results: Higher uptake and a longer effective half-life of 177Lu-DOTA-LM3 was found for whole-body as well as kidneys, spleen, and metastases, resulting in higher mean absorbed organ and tumor doses as compared to the agonist 177Lu-DOTA-TOC. All patients tolerated therapy without any serious acute adverse effects. Mild nausea without vomiting was observed in 5 (9.8%) patients; no other symptoms were reported. The most severe delayed adverse event was CTC-3 thrombocytopenia in 3 (5.9%) patients. Neither CTC-4 thrombocytopenia nor CTC-3-4 anemia or leukopenia was observed after treatment. No significant decline in renal function was observed, nor was hepatotoxicity. According to RECIST 1.1, disease control could be reached in 40 patients (disease control rate, 85.1%) of 47 patients monitored after 177Lu-DOTA-LM3 PRRT, with a partial response in 17 (36.2%) and stable disease in 23 (48.9%), whereas 7 (14.9%) patients had progressive disease, and by EORTC criteria, complete remission in 2 (4.3%), partial remission in 21 (44.7%), stable disease in 18 (38.3%), and progressive disease in 6 (12.8%) patients. Conclusion: "Antagonist PRRT" with 177Lu-DOTA-LM3 could be administered without severe adverse effects and was well tolerated by the majority of patients, with thrombocytopenia occurring only in a few patients. No other severe adverse effects were observed, particularly no nephrotoxicity. The SSTR antagonist 177Lu-DOTA-LM3 appears to be very promising for PRRT, provides favorable biodistribution and higher tumor radiation doses than SSTR agonists, and was very effective in treating advanced metastatic NENs, especially in patients with low or no SSTR agonist binding, even achieving complete remission in some patients.
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Affiliation(s)
- Richard P Baum
- THERANOSTICS Center for Radiomolecular Precision Oncology, ENETS Center of Excellence, Zentralklinik Bad Berka, Germany
| | - Jingjing Zhang
- THERANOSTICS Center for Radiomolecular Precision Oncology, ENETS Center of Excellence, Zentralklinik Bad Berka Bad, Germany
| | - Christiane Schuchardt
- THERANOSTICS Center for Radiomolecular Precision Oncology, ENETS Center of Excellence, Zentralklinik Bad Berka, Germany
| | - Dirk Mueller
- THERANOSTICS Center for Radiomolecular Precision Oncology, ENETS Center of Excellence, Zentralklinik Bad Berka, Germany
| | - Helmut Maecke
- Department of Nuclear Medicine, Medical Center, University Hospital of Freiburg, Germany
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Abstract
PET/computed tomography (CT) imaging increasingly is used in neuroendocrine neoplasms (NENs) for diagnosis, staging, monitoring, prognostication, and choosing treatment. Somatostatin PET analog tracers have added to the specificity by obtaining higher affinity to somatostatin receptors with 68Ga-labeled or 64Cu-labeled DOTA peptides compared with single-photon emission CT imaging isotopes. PET uptake correlates to tumor grade and is an essential part of theranostics with peptide receptor radionuclide treatment. This article focuses on the literature on head-to-head studies and meta-analyses of different combinations of peptide agonists and a few antagonists. Overall, the published data support the diagnostic capability of PET/CT imaging in NENs.
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Affiliation(s)
- Camilla Bardram Johnbeck
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen, Denmark; European Neuroendocrine Tumor Society Center of Excellence, Rigshospitalet, Copenhagen, Denmark
| | - Jann Mortensen
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen, Denmark; European Neuroendocrine Tumor Society Center of Excellence, Rigshospitalet, Copenhagen, Denmark; Medical Faculty, University of Copenhagen, Denmark.
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Synthesis, preclinical evaluation, and a pilot clinical imaging study of [ 18F]AlF-NOTA-JR11 for neuroendocrine neoplasms compared with [ 68Ga]Ga-DOTA-TATE. Eur J Nucl Med Mol Imaging 2021; 48:3129-3140. [PMID: 33630145 DOI: 10.1007/s00259-021-05249-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 02/07/2021] [Indexed: 12/16/2022]
Abstract
PURPOSE A [18F]AlF-labeled somatostatin receptor (SSTR) antagonist was developed for imaging of neuroendocrine neoplasms (NENs), evaluated and compared with [68Ga]Ga-DOTA-TATE. METHOD [18F]AlF-NOTA-JR11 was synthesized manually and qualified with high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS). The cellular uptake, internalization, and saturation binding were performed with HEK293-SSTR2 cells. Biodistribution and micro-PET imaging were carried out with HEK293-SSTR2 tumor-bearing mice. [18F]AlF-NOTA-JR11 PET/MR imaging and [68Ga]Ga-DOTA-TATE PET/CT were performed with ten patients of NEN at 50~60 min post-injection (p.i.). Normal organ biodistribution and tumor detectability were evaluated. RESULT [18F]AlF-NOTA-JR11(24~36 GBq/μmol) was prepared within 30 min and 51.35 ± 3.30% (n > 10)of radiochemical yield. The radiochemical purity was 98.74 ± 1.24% (n > 10). Two stereoisomers were found and confirmed by LC-MS. The cellular uptake of [18F]AlF-NOTA-JR11 and [68Ga]Ga-DOTA-TATE were 4.50 ± 0.31 and 4.50 ± 0.13 %AD/105 cells at 30 min, and the internalization at 37 °C of [18F]AlF-NOTA-JR11 (5.47 ± 0.32% at 60 min) was significantly lower than [68Ga]Ga-DOTA-TATE (66.89 ± 1.62% at 60 min). The affinity of [18F]AlF-NOTA-JR11 (Kd = 11.59 ± 1.31 nM) was slightly lower than [68Ga]Ga-DOTA-TATE (Kd = 7.36 ± 1.02 nM); [18F]AlF-NOTA-JR11 showed high uptake in tumor (9.02 ± 0.92 %ID/g at 60 min p.i.) which can be blocked by 50 μg of NOTA-JR11 (3.40 ± 1.64 %ID/g at 60 min p.i.); the result was coincident with micro-PET imaging. Imaging study of NEN patients showed that more lesions were found only by [18F]AlF-NOTA-JR11 (n = 67 vs. 1 only by [68Ga]Ga-DOTA-TATE), and the uptakes of [18F]AlF-NOTA-JR11 in majority normal organs were significantly lower than [68Ga]Ga-DOTA-TATE. The target to nontarget of maximum of standard uptake value (SUVmax) of [18F]AlF-NOTA-JR11 in liver lesions were significantly higher than those of [68Ga]Ga-DOTA-TATE. CONCLUSION Qualitied [18F]AlF-NOTA-JR11 is prepared conveniently with reasonable yield, and it can bind SSTR2 specifically with high affinity. Excellent imaging capability of [18F]AlF-NOTA-JR11 for NENs is superior to [68Ga]Ga-DOTA-TATE, especially in digestive system. It has a great potential for imaging of NENs.
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Klingler M, Hörmann AA, Guggenberg EV. Cholecystokinin-2 Receptor Targeting with Radiolabeled Peptides: Current Status and Future Directions. Curr Med Chem 2021; 27:7112-7132. [PMID: 32586246 DOI: 10.2174/0929867327666200625143035] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 05/01/2020] [Accepted: 05/13/2020] [Indexed: 02/08/2023]
Abstract
A wide variety of radiolabeled peptide analogs for specific targeting of cholecystokinin- 2 receptors (CCK2R) has been developed in the last decades. Peptide probes based on the natural ligands Minigastrin (MG) and Cholecystokinin (CCK) have a high potential for molecular imaging and targeted radiotherapy of different human tumors, such as Medullary Thyroid Carcinoma (MTC) and Small Cell Lung Cancer (SCLC). MG analogs with high persistent uptake in CCK2R expressing tumors have been preferably used for the development of radiolabeled peptide analogs. The clinical translation of CCK2R targeting has been prevented due to high kidney uptake or low metabolic stability of the different radiopeptides developed. Great efforts in radiopharmaceutical development have been undertaken to overcome these limitations. Various modifications in the linear peptide sequence of MG have been introduced mainly with the aim to reduce kidney retention. Furthermore, improved tumor uptake could be obtained by in situ stabilization of the radiopeptide against enzymatic degradation through coinjection of peptidase inhibitors. Recent developments focusing on the stabilization of the Cterminal receptor binding sequence (Trp-Met-Asp-Phe-NH2) have led to new radiolabeled MG analogs with highly improved tumor uptake and tumor-to-kidney ratio. In this review, all the different aspects in the radiopharmaceutical development of CCK2R targeting peptide probes are covered, giving also an overview on the clinical investigations performed so far. The recent development of radiolabeled MG analogs, which are highly stabilized against enzymatic degradation in vivo, promises to have a high impact on the clinical management of patients with CCK2R expressing tumors in the near future.
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Affiliation(s)
- Maximilian Klingler
- Department of Nuclear Medicine, Medical University of Innsbruck, A-6020 Innsbruck, Austria
| | - Anton Amadeus Hörmann
- Department of Nuclear Medicine, Medical University of Innsbruck, A-6020 Innsbruck, Austria
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Patel M, Tena I, Jha A, Taieb D, Pacak K. Somatostatin Receptors and Analogs in Pheochromocytoma and Paraganglioma: Old Players in a New Precision Medicine World. Front Endocrinol (Lausanne) 2021; 12:625312. [PMID: 33854479 PMCID: PMC8039528 DOI: 10.3389/fendo.2021.625312] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 03/04/2021] [Indexed: 12/16/2022] Open
Abstract
Neuroendocrine tumors overexpress somatostatin receptors, which serve as important and unique therapeutic targets for well-differentiated advanced disease. This overexpression is a well-established finding in gastroenteropancreatic neuroendocrine tumors which has guided new medical therapies in the administration of somatostatin analogs, both "cold", particularly octreotide and lanreotide, and "hot" analogs, chelated to radiolabeled isotopes. The binding of these analogs to somatostatin receptors effectively suppresses excess hormone secretion and tumor cell proliferation, leading to stabilization, and in some cases, tumor shrinkage. Radioisotope-labeled somatostatin analogs are utilized for both tumor localization and peptide radionuclide therapy, with 68Ga-DOTATATE and 177Lu-DOTATATE respectively. Benign and malignant pheochromocytomas and paragangliomas also overexpress somatostatin receptors, irrespective of embryological origin. The pattern of somatostatin receptor overexpression is more prominent in succinate dehydrogenase subunit B gene mutation, which is more aggressive than other subgroups of this disease. While the Food and Drug Administration has approved the use of 68Ga-DOTATATE as a radiopharmaceutical for somatostatin receptor imaging, the use of its radiotherapeutic counterpart still needs approval beyond gastroenteropancreatic neuroendocrine tumors. Thus, patients with pheochromocytoma and paraganglioma, especially those with inoperable or metastatic diseases, depend on the clinical trials of somatostatin analogs. The review summarizes the advances in the utilization of somatostatin receptor for diagnostic and therapeutic approaches in the neuroendocrine tumor subset of pheochromocytoma and paraganglioma; we hope to provide a positive perspective in using these receptors as targets for treatment in this rare condition.
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Affiliation(s)
- Mayank Patel
- Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - Isabel Tena
- Scientific Department, Medica Scientia Innovation Research (MedSIR), Barcelona, Spain
- Section of Medical Oncology, Consorcio Hospitalario Provincial of Castellon, Castellon, Spain
| | - Abhishek Jha
- Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
| | - David Taieb
- Department of Nuclear Medicine, La Timone University Hospital, CERIMED, Aix-Marseille University, Marseille, France
| | - Karel Pacak
- Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States
- *Correspondence: Karel Pacak,
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Aloj L, Attili B, Lau D, Caraco C, Lechermann LM, Mendichovszky IA, Harper I, Cheow H, Casey RT, Sala E, Gilbert FJ, Gallagher FA. The emerging role of cell surface receptor and protein binding radiopharmaceuticals in cancer diagnostics and therapy. Nucl Med Biol 2021; 92:53-64. [PMID: 32563612 DOI: 10.1016/j.nucmedbio.2020.06.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 06/10/2020] [Indexed: 12/17/2022]
Abstract
Targeting specific cell membrane markers for both diagnostic imaging and radionuclide therapy is a rapidly evolving field in cancer research. Some of these applications have now found a role in routine clinical practice and have been shown to have a significant impact on patient management. Several molecular targets are being investigated in ongoing clinical trials and show promise for future implementation. Advancements in molecular biology have facilitated the identification of new cancer-specific targets for radiopharmaceutical development.
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Affiliation(s)
- Luigi Aloj
- Department of Radiology, University of Cambridge, Cambridge, United Kingdom; Department of Nuclear Medicine, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom; Cancer Research UK Cambridge Centre, Cambridge, United Kingdom.
| | - Bala Attili
- Department of Radiology, University of Cambridge, Cambridge, United Kingdom; Cancer Research UK Cambridge Centre, Cambridge, United Kingdom
| | - Doreen Lau
- Department of Radiology, University of Cambridge, Cambridge, United Kingdom; Cancer Research UK Cambridge Centre, Cambridge, United Kingdom
| | - Corradina Caraco
- Department of Radiology, University of Cambridge, Cambridge, United Kingdom
| | - Laura M Lechermann
- Department of Radiology, University of Cambridge, Cambridge, United Kingdom; Cancer Research UK Cambridge Centre, Cambridge, United Kingdom
| | - Iosif A Mendichovszky
- Department of Radiology, University of Cambridge, Cambridge, United Kingdom; Department of Nuclear Medicine, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom; Cancer Research UK Cambridge Centre, Cambridge, United Kingdom
| | - Ines Harper
- Department of Nuclear Medicine, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom
| | - Heok Cheow
- Department of Nuclear Medicine, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom
| | - Ruth T Casey
- Department of Endocrinology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom; Department of Medical Genetics, University of Cambridge, Cambridge, United Kingdom
| | - Evis Sala
- Department of Radiology, University of Cambridge, Cambridge, United Kingdom; Cancer Research UK Cambridge Centre, Cambridge, United Kingdom
| | - Fiona J Gilbert
- Department of Radiology, University of Cambridge, Cambridge, United Kingdom; Cancer Research UK Cambridge Centre, Cambridge, United Kingdom
| | - Ferdia A Gallagher
- Department of Radiology, University of Cambridge, Cambridge, United Kingdom; Cancer Research UK Cambridge Centre, Cambridge, United Kingdom
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Fani M, Weingaertner V, Kolenc Peitl P, Mansi R, Gaonkar RH, Garnuszek P, Mikolajczak R, Novak D, Simoncic U, Hubalewska-Dydejczyk A, Rangger C, Kaeopookum P, Decristoforo C. Selection of the First 99mTc-Labelled Somatostatin Receptor Subtype 2 Antagonist for Clinical Translation-Preclinical Assessment of Two Optimized Candidates. Pharmaceuticals (Basel) 2020; 14:19. [PMID: 33379299 PMCID: PMC7824897 DOI: 10.3390/ph14010019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 02/01/2023] Open
Abstract
Recently, radiolabelled antagonists targeting somatostatin receptors subtype 2 (SST2) in neuroendocrine neoplasms demonstrated certain superior properties over agonists. Within the ERA-PerMED project "TECANT" two 99mTc-Tetramine (N4)-derivatized SST2 antagonists (TECANT-1 and TECANT-2) were studied for the selection of the best candidate for clinical translation. Receptor-affinity, internalization and dissociation studies were performed in human embryonic kidney-293 (HEK293) cells transfected with the human SST2 (HEK-SST2). Log D, protein binding and stability in human serum were assessed. Biodistribution and SPECT/CT studies were carried out in nude mice bearing HEK-SST2 xenografts, together with dosimetric estimations from mouse-to-man. [99mTc]Tc-TECANT-1 showed higher hydrophilicity and lower protein binding than [99mTc]-TECANT-2, while stability was comparable. Both radiotracers revealed similar binding affinity, while [99mTc]Tc-TECANT-1 had higher cellular uptake (>50%, at 2 h/37 °C) and lower dissociation rate (<30%, at 2 h/37 °C). In vivo, [99mTc]Tc-TECANT-1 showed lower blood values, kidney and muscles uptake, whereas tumour uptake was comparable to [99mTc]Tc-TECANT-2. SPECT/CT imaging confirmed the biodistribution results, providing the best tumour-to-background image contrast for [99mTc]Tc-TECANT-1 at 4 h post-injection (p.i.). The estimated radiation dose amounted to approximately 6 µSv/MBq for both radiotracers. This preclinical study provided the basis of selection of [99mTc]Tc-TECANT-1 for clinical translation of the first 99mTc-based SST2 antagonist.
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Affiliation(s)
- Melpomeni Fani
- Division of Radiopharmaceutical Chemistry, University Hospital Basel, Universitätsspital Basel, CH-4031 Basel, Switzerland; (M.F.); (R.M.); (R.H.G.)
| | - Viktoria Weingaertner
- Department of Nuclear Medicine, Medical University Innsbruck, 6020 Innsbruck, Austria; (V.W.); (C.R.); (P.K.)
| | - Petra Kolenc Peitl
- Department of Nuclear Medicine, University Medical Centre Ljubljana, University of Ljubljana, 1000 Ljubljana, Slovenia; (P.K.P.); (D.N.)
| | - Rosalba Mansi
- Division of Radiopharmaceutical Chemistry, University Hospital Basel, Universitätsspital Basel, CH-4031 Basel, Switzerland; (M.F.); (R.M.); (R.H.G.)
| | - Raghuvir H. Gaonkar
- Division of Radiopharmaceutical Chemistry, University Hospital Basel, Universitätsspital Basel, CH-4031 Basel, Switzerland; (M.F.); (R.M.); (R.H.G.)
| | - Piotr Garnuszek
- Radioisotope Centre POLATOM, National Centre for Nuclear Research, 05-400 Otwock, Poland; (P.G.); (R.M.)
| | - Renata Mikolajczak
- Radioisotope Centre POLATOM, National Centre for Nuclear Research, 05-400 Otwock, Poland; (P.G.); (R.M.)
| | - Doroteja Novak
- Department of Nuclear Medicine, University Medical Centre Ljubljana, University of Ljubljana, 1000 Ljubljana, Slovenia; (P.K.P.); (D.N.)
| | - Urban Simoncic
- Faculty of Mathematics and Physics, University of Ljubljana, 1000 Ljubljana, Slovenia;
| | | | - Christine Rangger
- Department of Nuclear Medicine, Medical University Innsbruck, 6020 Innsbruck, Austria; (V.W.); (C.R.); (P.K.)
| | - Piriya Kaeopookum
- Department of Nuclear Medicine, Medical University Innsbruck, 6020 Innsbruck, Austria; (V.W.); (C.R.); (P.K.)
| | - Clemens Decristoforo
- Department of Nuclear Medicine, Medical University Innsbruck, 6020 Innsbruck, Austria; (V.W.); (C.R.); (P.K.)
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Calabrò D, Argalia G, Ambrosini V. Role of PET/CT and Therapy Management of Pancreatic Neuroendocrine Tumors. Diagnostics (Basel) 2020; 10:diagnostics10121059. [PMID: 33297381 PMCID: PMC7762240 DOI: 10.3390/diagnostics10121059] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/02/2020] [Accepted: 12/04/2020] [Indexed: 12/12/2022] Open
Abstract
Pancreatic neuroendocrine neoplasms (panNENs) are heterogeneous neoplasms with neuroendocrine differentiation that show peculiar clinical and histomorphological features, with variable prognosis. In recent years, advances in knowledge regarding the pathophysiology and heterogeneous clinical presentation, as well as the availability of different diagnostic procedures for panNEN diagnosis and novel therapeutic options for patient clinical management, has led to the recognition of the need for an active multidisciplinary discussion for optimal patient care. Molecular imaging with positron emission tomography/computed tomography (PET/CT) has become indispensable for the management of panNENs. Several PET radiopharmaceuticals can be used to characterize either panNEN receptor expression or metabolism. The aim of this review is to offer an overview of all the currently used radiopharmaceuticals and of the new upcoming tracers for pancreatic neuroendocrine tumors (panNETs), and their clinical impact on therapy management. [68Ga]Ga-DOTA-peptide PET/CT (SSA-PET/CT) has high sensitivity, specificity, and accuracy and is recommended for the staging and restaging of any non-insulinoma well-differentiated panNEN cases to carry out detection of unknown primary tumor sites or early relapse and for evaluation of in vivo somatostatin receptors expression (SRE) to select patient candidates for peptide receptor radiometabolic treatment (PRRT) with 90Y or 177Lu and/or cold analogs. SSA-PET/CT also has a strong impact on clinical management, leading to a change in treatment in approximately a third of the cases. Its role for treatment response assessment is still under debate due to the lack of standardized criteria, even though some semiquantitative parameters seem to be able to predict response. [18F]FDG PET/CT generally shows low sensitivity in small growing and well-differentiated neuroendocrine tumors (NET; G1 and G2), while it is of utmost importance in the evaluation and management of high-grade NENs and also provides important prognostic information. When positive, [18F]FDG PET/CT impacts therapeutical management, indicating the need for a more aggressive treatment regime. Although FDG positivity does not exclude the patient from PRRT, several studies have demonstrated that it is certainly useful to predict response, even in this setting. The role of [18F]FDOPA for the study of panNET is limited by physiological uptake in the pancreas and is therefore not recommended. Moreover, it provides no information on SRE that has crucial clinical management relevance. Early acquisition of the abdomen and premedication with carbidopa may be useful to increase the accuracy, but further studies are needed to clarify its utility. GLP-1R agonists, such as exendin-4, are particularly useful for benign insulinoma detection, but their accuracy decreases in the case of malignant insulinomas. Being a whole-body imaging technique, exendin-PET/CT gives important preoperative information on tumor size and localization, which is fundamental for surgical planning as resection (enucleation of the lesion or partial pancreatic resection) is the only curative treatment. New upcoming tracers are under study, such as promising SSTR antagonists, which show a favorable biodistribution and higher tumor-to-background ratio that increases tumor detection, especially in the liver. [68Ga]pentixafor, an in vivo marker of CXCR4 expression associated with the behavior of more aggressive tumors, seems to only play a limited role in detecting well-differentiated NET since there is an inverse expression of SSTR2 and CXCR4 in G1 to G3 NETs with an elevation in CXCR4 and a decrease in SSTR2 expression with increasing grade. Other tracers, such as [68Ga]Ga-PSMA, [68Ga]Ga-DATA-TOC, [18F]SiTATE, and [18F]AlF-OC, are also under investigation.
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Affiliation(s)
- Diletta Calabrò
- Department of Nuclear Medicine, IRCCS Azienda Ospedaliera-Universitaria di Bologna, 40138 Bologna, Italy; (G.A.); (V.A.)
- Department of Nuclear Medicine, DIMES University of Bologna, 40138 Bologna, Italy
- Correspondence:
| | - Giulia Argalia
- Department of Nuclear Medicine, IRCCS Azienda Ospedaliera-Universitaria di Bologna, 40138 Bologna, Italy; (G.A.); (V.A.)
- Department of Nuclear Medicine, DIMES University of Bologna, 40138 Bologna, Italy
| | - Valentina Ambrosini
- Department of Nuclear Medicine, IRCCS Azienda Ospedaliera-Universitaria di Bologna, 40138 Bologna, Italy; (G.A.); (V.A.)
- Department of Nuclear Medicine, DIMES University of Bologna, 40138 Bologna, Italy
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Eychenne R, Bouvry C, Bourgeois M, Loyer P, Benoist E, Lepareur N. Overview of Radiolabeled Somatostatin Analogs for Cancer Imaging and Therapy. Molecules 2020; 25:E4012. [PMID: 32887456 PMCID: PMC7504749 DOI: 10.3390/molecules25174012] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 08/28/2020] [Accepted: 09/01/2020] [Indexed: 12/19/2022] Open
Abstract
Identified in 1973, somatostatin (SST) is a cyclic hormone peptide with a short biological half-life. Somatostatin receptors (SSTRs) are widely expressed in the whole body, with five subtypes described. The interaction between SST and its receptors leads to the internalization of the ligand-receptor complex and triggers different cellular signaling pathways. Interestingly, the expression of SSTRs is significantly enhanced in many solid tumors, especially gastro-entero-pancreatic neuroendocrine tumors (GEP-NET). Thus, somatostatin analogs (SSAs) have been developed to improve the stability of the endogenous ligand and so extend its half-life. Radiolabeled analogs have been developed with several radioelements such as indium-111, technetium-99 m, and recently gallium-68, fluorine-18, and copper-64, to visualize the distribution of receptor overexpression in tumors. Internal metabolic radiotherapy is also used as a therapeutic strategy (e.g., using yttrium-90, lutetium-177, and actinium-225). With some radiopharmaceuticals now used in clinical practice, somatostatin analogs developed for imaging and therapy are an example of the concept of personalized medicine with a theranostic approach. Here, we review the development of these analogs, from the well-established and authorized ones to the most recently developed radiotracers, which have better pharmacokinetic properties and demonstrate increased efficacy and safety, as well as the search for new clinical indications.
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Affiliation(s)
- Romain Eychenne
- UPS, CNRS, SPCMIB (Laboratoire de Synthèse et Physico-Chimie de Molécules d’Intérêt Biologique)—UMR 5068, Université de Toulouse, F-31062 Toulouse, France; (R.E.); (E.B.)
- Groupement d’Intérêt Public ARRONAX, 1 Rue Aronnax, F-44817 Saint Herblain, France;
- CNRS, CRCINA (Centre de Recherche en Cancérologie et Immunologie Nantes—Angers)—UMR 1232, ERL 6001, Inserm, Université de Nantes, F-44000 Nantes, France
| | - Christelle Bouvry
- Comprehensive Cancer Center Eugène Marquis, Rennes, F-35000, France;
- CNRS, ISCR (Institut des Sciences Chimiques de Rennes)—UMR 6226, Univ Rennes, F-35000 Rennes, France
| | - Mickael Bourgeois
- Groupement d’Intérêt Public ARRONAX, 1 Rue Aronnax, F-44817 Saint Herblain, France;
- CNRS, CRCINA (Centre de Recherche en Cancérologie et Immunologie Nantes—Angers)—UMR 1232, ERL 6001, Inserm, Université de Nantes, F-44000 Nantes, France
| | - Pascal Loyer
- INRAE, Institut NUMECAN (Nutrition, Métabolismes et Cancer)—UMR_A 1341, UMR_S 1241, Inserm, Univ Rennes, F-35000 Rennes, France;
| | - Eric Benoist
- UPS, CNRS, SPCMIB (Laboratoire de Synthèse et Physico-Chimie de Molécules d’Intérêt Biologique)—UMR 5068, Université de Toulouse, F-31062 Toulouse, France; (R.E.); (E.B.)
| | - Nicolas Lepareur
- Comprehensive Cancer Center Eugène Marquis, Rennes, F-35000, France;
- INRAE, Institut NUMECAN (Nutrition, Métabolismes et Cancer)—UMR_A 1341, UMR_S 1241, Inserm, Univ Rennes, F-35000 Rennes, France;
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