1
|
Gurung S, Timmermand OV, Perocheau D, Gil-Martinez AL, Minnion M, Touramanidou L, Fang S, Messina M, Khalil Y, Spiewak J, Barber AR, Edwards RS, Pinto PL, Finn PF, Cavedon A, Siddiqui S, Rice L, Martini PGV, Ridout D, Heywood W, Hargreaves I, Heales S, Mills PB, Waddington SN, Gissen P, Eaton S, Ryten M, Feelisch M, Frassetto A, Witney TH, Baruteau J. mRNA therapy corrects defective glutathione metabolism and restores ureagenesis in preclinical argininosuccinic aciduria. Sci Transl Med 2024; 16:eadh1334. [PMID: 38198573 PMCID: PMC7615535 DOI: 10.1126/scitranslmed.adh1334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Accepted: 10/06/2023] [Indexed: 01/12/2024]
Abstract
The urea cycle enzyme argininosuccinate lyase (ASL) enables the clearance of neurotoxic ammonia and the biosynthesis of arginine. Patients with ASL deficiency present with argininosuccinic aciduria, an inherited metabolic disease with hyperammonemia and a systemic phenotype coinciding with neurocognitive impairment and chronic liver disease. Here, we describe the dysregulation of glutathione biosynthesis and upstream cysteine utilization in ASL-deficient patients and mice using targeted metabolomics and in vivo positron emission tomography (PET) imaging using (S)-4-(3-18F-fluoropropyl)-l-glutamate ([18F]FSPG). Up-regulation of cysteine metabolism contrasted with glutathione depletion and down-regulated antioxidant pathways. To assess hepatic glutathione dysregulation and liver disease, we present [18F]FSPG PET as a noninvasive diagnostic tool to monitor therapeutic response in argininosuccinic aciduria. Human hASL mRNA encapsulated in lipid nanoparticles improved glutathione metabolism and chronic liver disease. In addition, hASL mRNA therapy corrected and rescued the neonatal and adult Asl-deficient mouse phenotypes, respectively, enhancing ureagenesis. These findings provide mechanistic insights in liver glutathione metabolism and support clinical translation of mRNA therapy for argininosuccinic aciduria.
Collapse
Affiliation(s)
- Sonam Gurung
- Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | | | - Dany Perocheau
- Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Ana Luisa Gil-Martinez
- Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Magdalena Minnion
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO17 1BJ, UK
- Southampton NIHR Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | - Loukia Touramanidou
- Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Sherry Fang
- Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
| | - Martina Messina
- Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
| | - Youssef Khalil
- Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Justyna Spiewak
- Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Abigail R Barber
- School of Biomedical Engineering and Imaging Sciences, King's College London, London SE1 7EH, UK
| | - Richard S Edwards
- School of Biomedical Engineering and Imaging Sciences, King's College London, London SE1 7EH, UK
| | - Patricia Lipari Pinto
- Santa Maria's Hospital, Lisbon North University Hospital Center, 1649-028 Lisbon, Portugal
| | | | | | | | - Lisa Rice
- Moderna Inc., Cambridge, MA 02139, USA
| | | | - Deborah Ridout
- Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Wendy Heywood
- Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Ian Hargreaves
- Pharmacy and Biomolecular Sciences, Liverpool John Moore University, Liverpool L3 5UG, UK
| | - Simon Heales
- Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
- Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
| | - Philippa B Mills
- Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Simon N Waddington
- EGA Institute for Women's Health, University College London, London WC1E 6HX, UK
- Wits/SAMRC Antiviral Gene Therapy Research Unit, Faculty of Health Sciences, University of Witswatersrand, Braamfontein, 2000 Johannesburg, South Africa
| | - Paul Gissen
- Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
- Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
- National Institute of Health Research Great Ormond Street Biomedical Research Centre, London WC1N 1EH, UK
| | - Simon Eaton
- Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Mina Ryten
- Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - Martin Feelisch
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO17 1BJ, UK
- Southampton NIHR Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust, Southampton SO16 6YD, UK
| | | | - Timothy H Witney
- School of Biomedical Engineering and Imaging Sciences, King's College London, London SE1 7EH, UK
| | - Julien Baruteau
- Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
- Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
- National Institute of Health Research Great Ormond Street Biomedical Research Centre, London WC1N 1EH, UK
| |
Collapse
|
2
|
Timmermand OV, Witney TH. Imaging the Tumor Antioxidant Response with [ 18F]FSPG PET. Methods Mol Biol 2024; 2729:233-249. [PMID: 38006500 DOI: 10.1007/978-1-0716-3499-8_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2023]
Abstract
(4S)-4-(3-[18F]Fluoropropyl)-L-glutamic acid ([18F]FSPG) is a flourine-18 labeled glutamate analog that enables the noninvasive in vivo imaging of cellular redox status. [18F]FSPG is transported across the cell membrane by the cystine/glutamate antiporter, system xc-, whose expression is upregulated in multiple cancer types. The requirement of cystine for the biosynthesis of glutathione, a major antioxidant, connects [18F]FSPG tissue retention to the intracellular redox response via system xc- activity. We herein describe the use of [18F]FSPG positron emission tomography (PET) to image the tumor antioxidant response and highlight key methodological considerations.
Collapse
Affiliation(s)
| | - Timothy H Witney
- School of Biomedical Engineering & Imaging Sciences, King's College London, London, UK.
| |
Collapse
|
3
|
Greenwood HE, Edwards RS, Tyrrell WE, Barber AR, Baark F, Tanc M, Khalil E, Falzone A, Ward NP, DeBlasi JM, Torrente L, Pearce DR, Firth G, Smith LM, Timmermand OV, Huebner A, George ME, Swanton C, Hynds RE, DeNicola GM, Witney TH. Imaging the master regulator of the antioxidant response in non-small cell lung cancer with positron emission tomography. bioRxiv 2023:2023.12.16.572007. [PMID: 38168428 PMCID: PMC10760199 DOI: 10.1101/2023.12.16.572007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Mutations in the NRF2-KEAP1 pathway are common in non-small cell lung cancer (NSCLC) and confer broad-spectrum therapeutic resistance, leading to poor outcomes. The cystine/glutamate antiporter, system xc-, is one of the >200 cytoprotective proteins controlled by NRF2, which can be non-invasively imaged by (S)-4-(3-18F-fluoropropyl)-l-glutamate ([18F]FSPG) positron emission tomography (PET). Through genetic and pharmacologic manipulation, we show that [18F]FSPG provides a sensitive and specific marker of NRF2 activation in advanced preclinical models of NSCLC. We validate imaging readouts with metabolomic measurements of system xc- activity and their coupling to intracellular glutathione concentration. A redox gene signature was measured in patients from the TRACERx 421 cohort, suggesting an opportunity for patient stratification prior to imaging. Furthermore, we reveal that system xc- is a metabolic vulnerability that can be therapeutically targeted for sustained tumour growth suppression in aggressive NSCLC. Our results establish [18F]FSPG as predictive marker of therapy resistance in NSCLC and provide the basis for the clinical evaluation of both imaging and therapeutic agents that target this important antioxidant pathway.
Collapse
Affiliation(s)
- Hannah E. Greenwood
- School of Biomedical Engineering & Imaging Sciences, King’s College London, St Thomas’ Hospital, London, SE1 7EH, UK
| | - Richard S. Edwards
- School of Biomedical Engineering & Imaging Sciences, King’s College London, St Thomas’ Hospital, London, SE1 7EH, UK
| | - Will E. Tyrrell
- School of Biomedical Engineering & Imaging Sciences, King’s College London, St Thomas’ Hospital, London, SE1 7EH, UK
| | - Abigail R. Barber
- School of Biomedical Engineering & Imaging Sciences, King’s College London, St Thomas’ Hospital, London, SE1 7EH, UK
| | - Friedrich Baark
- School of Biomedical Engineering & Imaging Sciences, King’s College London, St Thomas’ Hospital, London, SE1 7EH, UK
| | - Muhammet Tanc
- School of Biomedical Engineering & Imaging Sciences, King’s College London, St Thomas’ Hospital, London, SE1 7EH, UK
| | - Eman Khalil
- School of Biomedical Engineering & Imaging Sciences, King’s College London, St Thomas’ Hospital, London, SE1 7EH, UK
| | - Aimee Falzone
- Department of Metabolism and Physiology, H. Lee Moffitt Cancer Center, Tampa, FL 33612, USA
| | - Nathan P. Ward
- Department of Metabolism and Physiology, H. Lee Moffitt Cancer Center, Tampa, FL 33612, USA
| | - Janine M. DeBlasi
- Department of Metabolism and Physiology, H. Lee Moffitt Cancer Center, Tampa, FL 33612, USA
| | - Laura Torrente
- Department of Metabolism and Physiology, H. Lee Moffitt Cancer Center, Tampa, FL 33612, USA
| | - David R. Pearce
- CRUK Lung Cancer Centre of Excellence, UCL Cancer Institute, University College London, WC1E 6DD, UK
- Cancer Evolution and Genome Instability Laboratory, The Francis Crick Institute, London, NW1 1AT, UK
| | - George Firth
- School of Biomedical Engineering & Imaging Sciences, King’s College London, St Thomas’ Hospital, London, SE1 7EH, UK
| | - Lydia M. Smith
- School of Biomedical Engineering & Imaging Sciences, King’s College London, St Thomas’ Hospital, London, SE1 7EH, UK
| | - Oskar Vilhelmsson Timmermand
- School of Biomedical Engineering & Imaging Sciences, King’s College London, St Thomas’ Hospital, London, SE1 7EH, UK
| | - Ariana Huebner
- CRUK Lung Cancer Centre of Excellence, UCL Cancer Institute, University College London, WC1E 6DD, UK
- Cancer Evolution and Genome Instability Laboratory, The Francis Crick Institute, London, NW1 1AT, UK
| | - Madeleine E. George
- School of Biomedical Engineering & Imaging Sciences, King’s College London, St Thomas’ Hospital, London, SE1 7EH, UK
| | - Charles Swanton
- CRUK Lung Cancer Centre of Excellence, UCL Cancer Institute, University College London, WC1E 6DD, UK
- Cancer Evolution and Genome Instability Laboratory, The Francis Crick Institute, London, NW1 1AT, UK
| | - Robert E. Hynds
- CRUK Lung Cancer Centre of Excellence, UCL Cancer Institute, University College London, WC1E 6DD, UK
- Cancer Evolution and Genome Instability Laboratory, The Francis Crick Institute, London, NW1 1AT, UK
| | - Gina M. DeNicola
- Department of Metabolism and Physiology, H. Lee Moffitt Cancer Center, Tampa, FL 33612, USA
| | - Timothy H. Witney
- School of Biomedical Engineering & Imaging Sciences, King’s College London, St Thomas’ Hospital, London, SE1 7EH, UK
| |
Collapse
|
4
|
Vilhelmsson Timmermand O, Safi M, Holmqvist B, Strand J. Evaluation of enhanced permeability effect and different linear energy transfer of radionuclides in a prostate cancer xenograft model. Am J Nucl Med Mol Imaging 2023; 13:147-155. [PMID: 37736493 PMCID: PMC10509292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 07/30/2023] [Indexed: 09/23/2023]
Abstract
We have previously investigated the biodistribution and therapy effect of a humanized monoclonal antibody targeting free prostate-specific antigen (fPSA) intended for theranostics of hormone-refractory prostate cancer. In the present study, we evaluated the off-target effect and different linear energy transfer (LET) radionuclides without the effect of PSA targeting by using an antibody with the same scaffold as previously used immunoconjugates but with random, non-specific, antigen binding region. This allows us to identify alterations generated by specific targeting and those related to passive bystander effects, such as enhanced permeability and retention (EPR). A control humanized IgG monoclonal antibody (hIgG1) and an isotype control IgG monoclonal antibody were conjugated with the chelator CHX-A"-DTPA. The immunoconjugate was radiolabeled with either Lutetium-177 ([177Lu]Lu) or Indium-111 ([111In]In). A biodistribution study in mice carrying LNCaP xenografts, was performed to evaluate the non-specific uptake of [177Lu]Lu-hIgG1 in tumors and normal organs. Further, therapy studies of [177Lu]Lu and [111In]In labeled IgG were performed in BALB/c mice carrying LNCaP xenografts. Tumor tissues of treated xenografts and control were sectioned and immunohistochemically stained for Ki67 and PSA. The highest tumor uptake for the [177Lu]Lu-hIgG1 was seen at 72 hours (7.2±2 %IA/g), when comparing the tumor uptake of the fPSA targeting antibody to the non-specific antibody, the non-specific antibody contributes to half of the tumor uptake at 72 h. The liver uptake was 3.1±0.5 %IA/g at 24 h, 2.8±0.5 %IA/g at 72 h and 1.3±0.6 %IA/g at 120 h in LNCaP xenografts, which was approximately three times lower at 24 h and two times lower at 72 h than for the antibody with preserved targeting. Immunohistochemical labeling showed a reduction of PSA expression and a reduction of Ki67 labeled cells in the [111In]In treated LNCaP tumors, compared to vehicle and [177Lu]Lu treated mice. In conclusion, we found that specific targeting might negatively influence normal organ uptake when targeting secreted antigens. Furthermore, different energy deposition i.e. linear energy transfer of a radionuclide might have diverse effects on receptor expression and cell proliferation in tumors.
Collapse
Affiliation(s)
| | | | | | - Joanna Strand
- Department of Oncology, Lund UniversityLund, Sweden
- Department of Hematology, Oncology, Radiation Physics, Skåne University Hospital, Lund UniversityLund, Sweden
| |
Collapse
|
5
|
Kristiansson A, Vilhelmsson Timmermand O, Altai M, Strand J, Strand SE, Åkerström B, Örbom A. Hematological Toxicity in Mice after High Activity Injections of 177Lu-PSMA-617. Pharmaceutics 2022; 14:pharmaceutics14040731. [PMID: 35456565 PMCID: PMC9032768 DOI: 10.3390/pharmaceutics14040731] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 03/21/2022] [Accepted: 03/26/2022] [Indexed: 01/10/2023] Open
Abstract
Prostate cancer (PC) is one of the most common malignancies affecting men, with poor prognosis after progression to metastatic castration-resistant prostate cancer (mCRPC). Radioligand therapy (RLT) targeting the overexpressed PSMA on PC cells, with, e.g., 177Lu-PSMA-617, has been effective in reducing tumor burden and prolonging survival in mCRPC. However, it is not a curative method with kidney and bone marrow toxicity limiting the activity given to patients. Previous preclinical models have reported transient hematotoxicity for up to 120 MBq. This activity may still be too low to investigate the effect on renal function since it corresponds to an absorbed dose below 10 Gy, whereas the kidneys in a clinical setting usually receive an absorbed dose more than double. Here we investigated the hematotoxicity and recovery after administered activities of 120, 160, and 200 MBq in a 177Lu-PSMA-617 BALB/cAnNRj mouse model. The animals had an initial drop in white blood cells (WBC) starting 4 days post injection, which recovered after 21 days. The effect on red blood cells (RBC) and platelets was detected later; 17 days post-injection levels decreased compared to the control group. The reduction was restored again 32 days post injection. No correlation between injected activity and hematotoxicity was found. Our results suggest that activities up to 200 MBq of 177Lu-PSMA-617 give transient hematotoxicity from which animals recover within a month and no radiation-related deaths. Injecting these high activities could allow animal studies with increased clinical relevance when studying renal toxicity in animal models.
Collapse
Affiliation(s)
- Amanda Kristiansson
- Department of Clinical Sciences Lund, Oncology, Lund University, 222 42 Lund, Sweden; (O.V.T.); (M.A.); (J.S.); (S.-E.S.); (A.Ö.)
- Correspondence:
| | - Oskar Vilhelmsson Timmermand
- Department of Clinical Sciences Lund, Oncology, Lund University, 222 42 Lund, Sweden; (O.V.T.); (M.A.); (J.S.); (S.-E.S.); (A.Ö.)
| | - Mohamed Altai
- Department of Clinical Sciences Lund, Oncology, Lund University, 222 42 Lund, Sweden; (O.V.T.); (M.A.); (J.S.); (S.-E.S.); (A.Ö.)
| | - Joanna Strand
- Department of Clinical Sciences Lund, Oncology, Lund University, 222 42 Lund, Sweden; (O.V.T.); (M.A.); (J.S.); (S.-E.S.); (A.Ö.)
- Department of Hematology, Oncology, Radiation Physics, Skåne University Hospital, Lund University, 222 43 Lund, Sweden
| | - Sven-Erik Strand
- Department of Clinical Sciences Lund, Oncology, Lund University, 222 42 Lund, Sweden; (O.V.T.); (M.A.); (J.S.); (S.-E.S.); (A.Ö.)
- Department of Clinical Sciences Lund, Medical Radiation Physics, Lund University, 221 85 Lund, Sweden
| | - Bo Åkerström
- Department of Clinical Sciences Lund, Section for Infection Medicine, Lund University, 221 84 Lund, Sweden;
| | - Anders Örbom
- Department of Clinical Sciences Lund, Oncology, Lund University, 222 42 Lund, Sweden; (O.V.T.); (M.A.); (J.S.); (S.-E.S.); (A.Ö.)
| |
Collapse
|
6
|
Strand J, Sjöström K, Lamminmaki UJ, Vilhelmsson Timmermand O, Strand SE, Tran TA. Humanization, Radiolabeling and Biodistribution Studies of an IgG1-Type Antibody Targeting Uncomplexed PSA for Theranostic Applications. Pharmaceuticals (Basel) 2021; 14:ph14121251. [PMID: 34959652 PMCID: PMC8703390 DOI: 10.3390/ph14121251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 11/20/2021] [Accepted: 11/29/2021] [Indexed: 11/16/2022] Open
Abstract
Metastatic castration-resistant prostate cancer is today incurable. Conventional imaging methods have limited detection, affecting their ability to give an accurate outcome prognosis, and current therapies for metastatic prostate cancer are insufficient. This inevitably leads to patients relapsing with castration-resistant prostate cancer. Targeting prostate-specific antigens whose expression is closely linked to the activity in the androgen receptor pathway, and thus the pathogenesis of prostate cancer, is a possible way to increase specificity and reduce off-target effects. We have humanized and evaluated radioimmunoconjugates of a previously murine antibody, m5A10, targeting PSA intended for theranostics of hormone-refractory prostate cancer. The humanized antibody h5A10 was expressed in mammalian HEK293 cells transfected with the nucleotide sequences for the heavy and light chains of the antibody. Cell culture medium was filtered and purified by Protein G chromatography, and the buffer was changed to PBS pH 7.4 by dialysis. Murine and humanized 5A10 were conjugated with p-SCN-Bn-CHX-A”-DTPA. Surface plasmon resonance was used to characterize the binding to PSA of the immunoconjugates. Immunoconjugates were labeled with either indium-111 or lutetium-177. Biodistribution studies of murine and humanized 5A10 were performed in mice with LNCaP xenografts. 5A10 was successfully humanized, and in vivo targeting showed specific binding in xenografts. The results thus give an excellent platform for further theranostic development of humanized 5A10 for clinical applications.
Collapse
Affiliation(s)
- Joanna Strand
- Department of Oncology, Department of Clinical Sciences, Lund University, 22243 Lund, Sweden; (O.V.T.); (S.-E.S.)
- Correspondence: (J.S.); (T.A.T.)
| | | | | | - Oskar Vilhelmsson Timmermand
- Department of Oncology, Department of Clinical Sciences, Lund University, 22243 Lund, Sweden; (O.V.T.); (S.-E.S.)
| | - Sven-Erik Strand
- Department of Oncology, Department of Clinical Sciences, Lund University, 22243 Lund, Sweden; (O.V.T.); (S.-E.S.)
- Department of Medical Radiation Physics, Department of Clinical Sciences, Lund University, 22243 Lund, Sweden
| | - Thuy A. Tran
- Department of Oncology and Pathology, Karolinska Institutet, 17177 Stockholm, Sweden
- Department of Radiopharmacy, Karolinska University Hospital, 17177 Stockholm, Sweden
- Correspondence: (J.S.); (T.A.T.)
| |
Collapse
|
7
|
Kristiansson A, Örbom A, Vilhelmsson Timmermand O, Ahlstedt J, Strand SE, Åkerström B. Kidney Protection with the Radical Scavenger α 1-Microglobulin (A1M) during Peptide Receptor Radionuclide and Radioligand Therapy. Antioxidants (Basel) 2021; 10:antiox10081271. [PMID: 34439519 PMCID: PMC8389303 DOI: 10.3390/antiox10081271] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 08/05/2021] [Accepted: 08/07/2021] [Indexed: 02/07/2023] Open
Abstract
α1-Microglobulin (A1M) is an antioxidant found in all vertebrates, including humans. It has enzymatic reductase activity and can scavenge radicals and bind free heme groups. Infused recombinant A1M accumulates in the kidneys and has therefore been successful in protecting kidney injuries in different animal models. In this review, we focus on A1M as a radioprotector of the kidneys during peptide receptor radionuclide/radioligand therapy (PRRT/RLT). Patients with, e.g., neuroendocrine tumors or castration resistant prostate cancer can be treated by administration of radiolabeled small molecules which target and therefore enable the irradiation and killing of cancer cells through specific receptor interaction. The treatment is not curative, and kidney toxicity has been reported as a side effect since the small, radiolabeled substances are retained and excreted through the kidneys. In recent studies, A1M was shown to have radioprotective effects on cell cultures as well as having a similar biodistribution as the somatostatin analogue peptide 177Lu-DOTATATE after intravenous infusion in mice. Therefore, several animal studies were conducted to investigate the in vivo radioprotective potential of A1M towards kidneys. The results of these studies demonstrated that A1M co-infusion yielded protection against kidney toxicity and improved overall survival in mouse models. Moreover, two different mouse studies reported that A1M did not interfere with tumor treatment itself. Here, we give an overview of radionuclide therapy, the A1M physiology and the results from the radioprotector studies of the protein.
Collapse
Affiliation(s)
- Amanda Kristiansson
- Department of Clinical Sciences Lund, Oncology, Lund University, 221 00 Lund, Sweden; (A.Ö.); (O.V.T.); (S.-E.S.)
- Correspondence:
| | - Anders Örbom
- Department of Clinical Sciences Lund, Oncology, Lund University, 221 00 Lund, Sweden; (A.Ö.); (O.V.T.); (S.-E.S.)
| | - Oskar Vilhelmsson Timmermand
- Department of Clinical Sciences Lund, Oncology, Lund University, 221 00 Lund, Sweden; (A.Ö.); (O.V.T.); (S.-E.S.)
| | - Jonas Ahlstedt
- Department of Clinical Sciences Lund, CIPA, Lund University, 221 84 Lund, Sweden;
| | - Sven-Erik Strand
- Department of Clinical Sciences Lund, Oncology, Lund University, 221 00 Lund, Sweden; (A.Ö.); (O.V.T.); (S.-E.S.)
- Department of Clinical Sciences Lund, Medical Radiation Physics, Lund University, 221 00 Lund, Sweden
| | - Bo Åkerström
- Department of Clinical Sciences Lund, Section for Infection Medicine, Lund University, 221 84 Lund, Sweden;
| |
Collapse
|
8
|
Vilhelmsson Timmermand O, Örbom A, Altai M, Zedan W, Holmqvist B, Safi M, Tran TA, Strand SE, Strand J. A Conjugation Strategy to Modulate Antigen Binding and FcRn Interaction Leads to Improved Tumor Targeting and Radioimmunotherapy Efficacy with an Antibody Targeting Prostate-Specific Antigen. Cancers (Basel) 2021; 13:cancers13143469. [PMID: 34298682 PMCID: PMC8307315 DOI: 10.3390/cancers13143469] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/15/2021] [Accepted: 07/07/2021] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The humanized monoclonal antibody (mAb) hu5A10 specifically targets and internalizes prostate cancer cells by binding to prostate specific antigen (PSA). Preclinical evaluations have shown that hu5A10 is an excellent vehicle for prostate cancer (PCa) radiotheranostics. We studied the impact of different chelates and conjugation ratios on hu5A10's target affinity, neonatal fc-receptor interaction on in vivo targeting efficacy, and possible enhanced therapeutic efficacy. METHODS In our experiment, humanized 5A10 (hu5A10) was conjugated with DOTA or DTPA at a molar ratio of 3:1, 6:1, and 12:1. Surface plasmon resonance (SPR) was used to study antigen and FcRn binding to the antibody conjugates. [111In]hu5A10 radio-immunoconjugates were administered intravenously into BALB/c mice carrying subcutaneous LNCaP xenografts. Serial Single-photon emission computed tomography (SPECT) images were obtained during the first week. Tumors were harvested and radionuclide distribution was analyzed by autoradiography along with microanatomy and immunohistochemistry. RESULTS As seen by SPR, the binding to PSA was clearly affected by the chelate-to-antibody ratio. Similarly, FcRn (neonatal fc-receptor) interacted less with antibodies conjugated at high ratios of chelator, which was more pronounced for DOTA conjugates. The autoradiography data indicated a higher distribution of radioactivity to the rim of the tumor for lower ratios and a more homogenous distribution at higher ratios. Mice injected with ratio 3:1 111In-DOTA-hu5A10 showed no significant difference in tumor volume when compared to mice given vehicle over a time period of 3 weeks. Mice given a similar injection of ratio 6:1 111In-DOTA-hu5A10 or 6:1 111In-DTPA-hu5A10 or 12:1 111In-DTPA-hu5A10 showed significant tumor growth retardation. Conclusions: The present study demonstrated that the radiolabeling strategy could positively modify the hu5A10's capacity to bind PSA and complex with the FcRn-receptor, which resulted in more homogenous activity distribution in tumors and enhanced therapy efficacy.
Collapse
Affiliation(s)
- Oskar Vilhelmsson Timmermand
- Department of Clinical Sciences Lund, Oncology, Lund University, 22243 Lund, Sweden; (O.V.T.); (A.Ö.); (M.A.); (W.Z.); (M.S.); (S.-E.S.)
| | - Anders Örbom
- Department of Clinical Sciences Lund, Oncology, Lund University, 22243 Lund, Sweden; (O.V.T.); (A.Ö.); (M.A.); (W.Z.); (M.S.); (S.-E.S.)
| | - Mohamed Altai
- Department of Clinical Sciences Lund, Oncology, Lund University, 22243 Lund, Sweden; (O.V.T.); (A.Ö.); (M.A.); (W.Z.); (M.S.); (S.-E.S.)
| | - Wahed Zedan
- Department of Clinical Sciences Lund, Oncology, Lund University, 22243 Lund, Sweden; (O.V.T.); (A.Ö.); (M.A.); (W.Z.); (M.S.); (S.-E.S.)
| | - Bo Holmqvist
- ImaGene-iT AB, Medicon Village, 22363 Lund, Sweden;
| | - Marcella Safi
- Department of Clinical Sciences Lund, Oncology, Lund University, 22243 Lund, Sweden; (O.V.T.); (A.Ö.); (M.A.); (W.Z.); (M.S.); (S.-E.S.)
| | - Thuy A. Tran
- Department of Radiopharmacy, Karolinska University Hospital, 17177 Stockholm, Sweden;
| | - Sven-Erik Strand
- Department of Clinical Sciences Lund, Oncology, Lund University, 22243 Lund, Sweden; (O.V.T.); (A.Ö.); (M.A.); (W.Z.); (M.S.); (S.-E.S.)
- Department of Clinical Sciences Lund, Medical Radiation Physics, Lund University, 22243 Lund, Sweden
| | - Joanna Strand
- Department of Clinical Sciences Lund, Oncology, Lund University, 22243 Lund, Sweden; (O.V.T.); (A.Ö.); (M.A.); (W.Z.); (M.S.); (S.-E.S.)
- Department of Clinical Oncology, Skane University Hospital, 22243 Lund, Sweden
- Correspondence: ; Tel.: +46-736839033
| |
Collapse
|
9
|
Vilhelmsson Timmermand O, Strand SE, Ceberg C, Ceder JA. An aggressive RhoC phenotype is associated with relapse after external beam radiation therapy of a prostate cancer xenograft model. J Clin Oncol 2019. [DOI: 10.1200/jco.2019.37.15_suppl.e14748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
e14748 Background: Relapsed treatment resistant prostate cancer remains the second most common cause of male mortality in the western world. New therapies for therapy resistant prostate cancer depend on defining tumor cell sub-populations capable of surviving, reinitiating, and sustaining net growth of the cancer. In this study we focused on RhoC expression in a prostate cancer model after external beam radiation therapy (EBRT). RhoC has earlier been implicated in metastatic processes in most solid tumors. Methods: In mice, established s.c. LNCaP xenografts (n = 12) were irradiated, the beam collimated with lead to restrict it to the xenograft, with X-rays (200 kV, 1 Gymin-1, Gulmay Medical) for an absorbed dose of 15 Gy. Tumor tissue was collected after seven days or after 3-4 weeks when recurrent growth was seen. RhoC, AR, CD166 and Ki67 immunohistochemistry in tumor sections was visualized by using DAB or Peroxidase Green and nuclear red or haematoxylin blue as counter stain. Sections stained for RhoC and Ki67 were quantified with the Halo software (v2.3.2089.34) using the Indica Labs – cytonuclear v1.6 algorithm. The intensity of the RhoC staining was also quantified in a separate set of sections only stained for RhoC. Results: The RhoC staining intensity was significantly higher in relapsed xenografts (P = 0.003). Also, a significant difference in percentage of RhoC expressing cells in the two populations (P = 0.045) with 40.6 ± 5.8% (mean ± SEM) in relapsed tumors as compared to 15.0 ± 8.1% after 7d. The percentage of cells expressing Ki67 was not significantly different (P = 0.477). However, the percentage of double positive cells (Ki67, RhoC) was significantly higher in treated relapsed xenografts (P = 0.042). Further, a subpopulation of RhoC-positive cells were positive for AR and the stem cell marker CD166. Conclusions: Here we show that a subpopulation of proliferating RhoC-positive cells are more prevalent in relapsing PCa xenografts after EBRT, suggesting an aggressive phenotype that is associated with both proliferation and invasiveness. Another subpopulation of RhoC cells was found to express the prostate stem cell marker CD166, suggesting that pathways and properties involved in cellular self-renewal and invasiveness may be responsible for survival and recurrent growth in relapsed prostate tumors.
Collapse
Affiliation(s)
| | - Sven-Erik Strand
- Department of Clinical Sciences Lund, Division of Oncology, Lund University, Lund, Sweden
| | - Crister Ceberg
- Department of Clinical Sciences Lund, Division of Medical Radiation Physics, Lund University, Lund, Sweden
| | - Jens Adam Ceder
- Department of Clinical Sciences Lund, Division of Oncology, Lund University, Lund, Sweden
| |
Collapse
|
10
|
Timmermand OV, Elgqvist J, Beattie KA, Örbom A, Larsson E, Eriksson SE, Thorek DL, Beattie BJ, Tran TA, Ulmert D, Strand SE. Preclinical efficacy of hK2 targeted [ 177Lu]hu11B6 for prostate cancer theranostics. Theranostics 2019; 9:2129-2142. [PMID: 31149033 PMCID: PMC6531309 DOI: 10.7150/thno.31179] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 01/17/2019] [Indexed: 12/12/2022] Open
Abstract
Androgen ablating drugs increase life expectancy in men with metastatic prostate cancer, but resistance inevitably develops. In a majority of these recurrent tumors, the androgen axis is reactivated in the form of increased androgen receptor (AR) expression. Targeting proteins that are expressed as a down-stream effect of AR activity is a promising rationale for management of this disease. The humanized IgG1 antibody hu11B6 internalizes into prostate and prostate cancer (PCa) cells by binding to the catalytic cleft of human kallikrein 2 (hK2), a prostate specific enzyme governed by the AR-pathway. In a previous study, hu11B6 conjugated with Actinium-225 (225Ac), a high linear energy transfer (LET) radionuclide, was shown to generate an AR-upregulation driven feed-forward mechanism that is believed to enhance therapeutic efficacy. We assessed the efficacy of hu11B6 labeled with a low LET beta-emitter, Lutetium-177 (177Lu) and investigated whether similar tumor killing and AR-enhancement is produced. Moreover, single-photon emission computed tomography (SPECT) imaging of 177Lu is quantitatively accurate and can be used to perform treatment planning. [177Lu]hu11B6 therefore has significant potential as a theranostic agent. Materials and Methods: Subcutaneous PCa xenografts (LNCaP s.c.) were grown in male mice. Biokinetics at 4-336 h post injection and uptake as a function of the amount of hu11B6 injected at 72 h were studied. Over a 30 to 120-day treatment period the therapeutic efficacy of different activities of [177Lu]hu11B6 were assessed by volumetric tumor measurements, blood cell counts, molecular analysis of the tumor as well as SPECT/CT imaging. Organ specific mean absorbed doses were calculated, using a MIRD-scheme, based on biokinetic data and rodent specific S-factors from a modified MOBY phantom. Tumor tissues of treated xenografts were immunohistochemically (IHC) stained for Ki-67 (proliferation) and AR, SA-β-gal activity (senescence) and analyzed by digital autoradiography (DAR). Results: Organ-to-blood and tumor-to-blood ratios were independent of hu11B6 specific activity except for the highest amount of antibody (150 µg). Tumor accumulation of [177Lu]hu11B6 peaked at 168 h with a specific uptake of 29 ± 9.1 percent injected activity per gram (%IA/g) and low accumulation in normal organs except in the submandibular gland (15 ± 4.5 %IA/g), attributed to a cross-reaction with mice kallikreins in this organ, was seen. However, SPECT imaging with therapeutic amounts of [177Lu]hu11B6 revealed no peak in tumor accumulation at 7 d, probably due to cellular retention of 177Lu and decreasing tumor volumes. For [177Lu]hu11B6 treated mice, tumor decrements of up to 4/5 of the initial tumor volume and reversible myelotoxicity with a nadir at 12 d were observed after a single injection. Tumor volume reduction correlated with injected activity and the absorbed dose. IHC revealed retained expression of AR throughout treatment and that Ki-67 staining reached a nadir at 9-14 d which coincided with high SA- β-gal activity (14 d). Quantification of nuclei staining showed that Ki-67 expression correlated negatively with activity uptake. AR expression levels in cells surviving therapy compared to previous timepoints and to controls at 30 d were significantly increased (p = 0.017). Conclusions: This study shows that hu11B6 labeled with the low LET beta-emitting radionuclide 177Lu can deliver therapeutic absorbed doses to prostate cancer xenografts with transient hematological side-effects. The tumor response correlated with the absorbed dose both on a macro and a small scale dosimetric level. Analysis of AR staining showed that AR protein levels increased late in the study suggesting a therapeutic mechanism, a feed forward mechanism coupled to AR driven response to DNA damage or clonal lineage selection, similar to that reported in high LET alpha-particle therapy using 225Ac labeled hu11B6, however emerging at a later timepoint.
Collapse
|
11
|
Evans-Axelsson S, Timmermand OV, Bjartell A, Strand SE, Elgqvist J. Radioimmunotherapy for Prostate Cancer--Current Status and Future Possibilities. Semin Nucl Med 2016; 46:165-79. [PMID: 26897720 DOI: 10.1053/j.semnuclmed.2015.10.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Prostate cancer (PCa) is one of the most common cancers in men and is the second leading cause of cancer-related deaths in the USA. In the United States, it is the second most frequently diagnosed cancer after skin cancer, and in Europe it is number one. According to the American Cancer Society, approximately 221,000 men in the United States would be diagnosed with PCa during 2015, and approximately 28,000 would die of the disease. According to the International Agency for Research on Cancer, approximately 345,000 men were diagnosed with PCa in Europe during 2012, and despite more emphasis placed on early detection through routine screening, 72,000 men died of the disease. Hence, the need for improved therapy modalities is of utmost importance. And targeted therapies based on radiolabeled specific antibodies or peptides are a very interesting and promising alternative to increase the therapeutic efficacy and overall chance of survival of these patients. There are currently several preclinical and some clinical studies that have been conducted, or are ongoing, to investigate the therapeutic efficacy and toxicity of radioimmunotherapy (RIT) against PCa. One thing that is lacking in a lot of these published studies is the dosimetry data, which are needed to compare results between the studies and the study locations. Given the complicated tumor microenvironment and overall complexity of RIT to PCa, old and new targets and targeting strategies like combination RIT and pretargeting RIT are being improved and assessed along with various therapeutic radionuclides candidates. Given alone or in combination with other therapies, these new and improved strategies and RIT tools further enhance the clinical response to RIT drugs in PCa, making RIT for PCa an increasingly practical clinical tool.
Collapse
Affiliation(s)
- Susan Evans-Axelsson
- Department of Translational Medicine, Division of Urological Cancers, Skåne University Hospital, Malmö, Lund University, Lund, Sweden
| | | | - Anders Bjartell
- Department of Translational Medicine, Division of Urological Cancers, Skåne University Hospital, Malmö, Lund University, Lund, Sweden; Department of Urology, Skåne University Hospital, Malmö, Sweden
| | - Sven-Erik Strand
- Department of Clinical Sciences, Lund, Division of Medical Radiation Physics, Lund University, Lund, Sweden
| | - Jörgen Elgqvist
- Department of Clinical Sciences, Lund, Division of Medical Radiation Physics, Lund University, Lund, Sweden.
| |
Collapse
|
12
|
Elgqvist J, Timmermand OV, Larsson E, Strand SE. Radiosensitivity of Prostate Cancer Cell Lines for Irradiation from Beta Particle-emitting Radionuclide ¹⁷⁷Lu Compared to Alpha Particles and Gamma Rays. Anticancer Res 2016; 36:103-109. [PMID: 26722033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
AIM The purpose of the present study was to investigate the radiosensitivity of the prostate cancer cell lines LNCaP, DU145, and PC3 when irradiated with beta particles emitted from (177)Lu, and to compare the effect with irradiation using alpha particles or gamma rays. MATERIALS AND METHODS Cells were irradiated with beta particles emitted from (177)Lu, alpha particles from (241)Am, or gamma rays from (137)Cs. A non-specific polyclonal antibody was labeled with (177)Lu and used to irradiate cells in suspension with beta particles. A previously described in-house developed alpha-particle irradiator based on a (241)Am source was used to irradiate cells with alpha particles. External gamma-ray irradiation was achieved using a standard (137)Cs irradiator. Cells were irradiated to absorbed doses equal to 0, 0.5, 1, 2, 4, 6, 8, or 10 Gy. The absorbed doses were calculated as mean absorbed doses. For evaluation of cell survival, the tetrazolium-based WST-1 assay was used. After irradiation, WST-1 was added to the cell solutions, incubated, and then measured for level of absorbance at 450 nm, indicating the live and viable cells. RESULTS LNCaP, DU145, and PC3 cell lines all had similar patterns of survival for the different radiation types. No significant difference in surviving fractions were observed between cells treated with beta-particle and gamma-ray irradiation, represented for example by the surviving fraction values (mean±SD) at 2, 6, and 10 Gy (SF2, SF6, and SF10) for DU145 after beta-particle irradiation: 0.700±0.090, 0.186±0.050 and 0.056±0.010, respectively. A strong radiosensitivity to alpha particles was observed, with SF2 values of 0.048±0.008, 0.018±0.006 and 0.015±0.005 for LNCaP, DU145, and PC3, respectively. CONCLUSION The surviving fractions after irradiation using beta particles or gamma rays did not differ significantly at the absorbed dose levels and dose rates used. Irradiation using alpha particles led to a high level of cell killing. The results show that the beta-particle emitter (177)Lu as well as alpha-particles are both good candidates for radionuclide-therapy applications in the treatment of prostate cancer.
Collapse
Affiliation(s)
- Jörgen Elgqvist
- Department of Medical Radiation Physics, Institute of Clinical Sciences, Lund University, Lund, Sweden
| | | | - Erik Larsson
- Department of Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Sven-Erik Strand
- Department of Medical Radiation Physics, Institute of Clinical Sciences, Lund University, Lund, Sweden
| |
Collapse
|
13
|
Timmermand OV, Tran TA, Strand SE, Axelsson J. Intratherapeutic biokinetic measurements, dosimetry parameter estimates, and monitoring of treatment efficacy using cerenkov luminescence imaging in preclinical radionuclide therapy. J Nucl Med 2015; 56:444-9. [PMID: 25655628 DOI: 10.2967/jnumed.114.148544] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
UNLABELLED In recent years, there has been increasing interest in noninvasive Cerenkov luminescence imaging (CLI) of in vivo radionuclide distribution in small animals, a method proven to be a high-throughput modality for confirmation of tracer uptake. 11B6 is an IgG1 monoclonal antibody that is specific to free human kallikrein-related peptidase 2, an antigen abundant in malignant prostatic tissue. Free human kallikrein-related peptidase 2 was targeted in prostate cancer xenografts using (177)Lu-labeled 11B6 in either murine or humanized forms for radionuclide therapy. In this setting, CLI was investigated as a tool for providing parameters of dosimetric importance during radionuclide therapy. First, longitudinal imaging of biokinetics using CLI and SPECT was compared. Second, the CLI signal was correlated to quantitative ex vivo tumor activity measurements. Finally, CLI was used to monitor the radionuclide treatment, and the integrated CLI radiance was found to correlate well with subject-specific tumor volume reduction. METHODS 11B6 was radiolabeled with (177)Lu through the CHX-A″-DTPA chelator. In vivo CLI and SPECT imaging of (177)Lu-DTPA-11B6 uptake was performed on NMRI and BALB/c nude mice with subcutaneous LNCaP xenografts up to 14 d after injection. Tumor size was measured to assess response to radionuclide therapy. RESULTS CLI correlated well with SPECT imaging and could be applied up to 14 d after injection of 20 MBq with the specific tracer used. Through integration of the CLI radiance as a function of time, a dose metric for the tumors could be formed that correlated exponentially with tumor volume reduction. CONCLUSION CLI provided valuable intratherapeutic biokinetic measurements for treatment monitoring and could be used as a tool for subject-specific absorbed dose estimation.
Collapse
Affiliation(s)
| | - Thuy A Tran
- Lund University Bioimaging Center, Lund University, Lund, Sweden; and
| | - Sven-Erik Strand
- Department of Medical Radiation Physics, Lund University, Lund, Sweden Lund University Bioimaging Center, Lund University, Lund, Sweden; and
| | - Johan Axelsson
- Division of Atomic Physics, Department of Physics, Lund University, Lund, Sweden
| |
Collapse
|
14
|
Timmermand OV, Ulmert D, Evans-Axelsson S, Pettersson K, Bjartell A, Lilja H, Strand SE, Tran TA. Preclinical imaging of kallikrein-related peptidase 2 (hK2) in prostate cancer with a (111)In-radiolabelled monoclonal antibody, 11B6. EJNMMI Res 2014; 4:51. [PMID: 26116115 PMCID: PMC4452661 DOI: 10.1186/s13550-014-0051-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 09/07/2014] [Indexed: 12/01/2022] Open
Abstract
Background Prostate cancer is a leading cause of death in the male population of the western world. Human kallikrein-related peptidase 2 (hK2) is abundantly expressed in malignant prostatic tissue, and its gene, KLK2, is regulated by the androgen receptor. 11B6 is a murine IgG1 monoclonal antibody directed against free human hK2. In this study, we performed a preclinical evaluation of 111In-labelled 11B6 in mouse xenografts to investigate its potential in the clinical staging and assessment of metastatic prostate cancer. Methods 11B6 was radiolabelled with 111In through CHX-A″-DTPA chelation. In vivo biodistribution and uptake of 111In-DTPA-11B6 were measured until 168 h post-injection in NMRI nude mice bearing subcutaneous LNCaP xenografts. The binding specificity to hK2 was evaluated by both in vivo competitive binding assays with excess non-labelled 11B6 and hK2-negative DU145 xenografts. SPECT/CT imaging of subcutaneous and intra-tibial LNCaP xenografts was used to visualize the tumours. Results Tumour uptake of 111In-DTPA-11B6 in LNCaP xenografts was 19% ± 0.78%IA/g at 48 h, giving a tumour-to-blood ratio of 1.6, which increases to 2.4 at 1 week post-injection. Accumulation was low in other organs except for the salivary glands, which is probably the result of cross-reactivity with mouse kallikreins. Significantly lower tumour accumulation was observed in competitive assays and DU145 xenografts. SPECT/CT imaging could clearly visualize the subcutaneous and intra-tibial LNCaP xenografts. Conclusions Our study demonstrates the potential of 111In-DTPA-11B6 for the detection of metastatic prostate cancer and monitoring anti-androgen therapy, as it exhibits an increased uptake and accumulation in viable tumour when compared to normal tissue. A humanised version of the 11B6 monoclonal antibody is currently under evaluation. Electronic supplementary material The online version of this article (doi:10.1186/s13550-014-0051-5) contains supplementary material, which is available to authorized users.
Collapse
|
15
|
Evans-Axelsson S, Vilhelmsson Timmermand O, Welinder C, Borrebaeck CAK, Strand SE, Tran TA, Jansson B, Bjartell A. Preclinical evaluation of (111)In-DTPA-INCA-X anti-Ku70/Ku80 monoclonal antibody in prostate cancer. Am J Nucl Med Mol Imaging 2014; 4:311-323. [PMID: 24982817 PMCID: PMC4074497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 05/14/2014] [Indexed: 06/03/2023]
Abstract
The aim of this investigation was to assess the Ku70/Ku80 complex as a potential target for antibody imaging of prostate cancer. We evaluated the in vivo and ex vivo tumor targeting and biodistribution of the (111)In-labeled human internalizing antibody, INCA-X ((111)In-DTPA-INCA-X antibody), in NMRI-nude mice bearing human PC-3, PC-3M-Lu2 or DU145 xenografts. DTPA-conjugated, non-labeled antibody was pre-administered at different time-points followed by a single intravenous injection of (111)In-DTPA-INCA-X. At 48, 72 and 96 h post-injection, tissues were harvested, and the antibody distribution was determined by measuring radioactivity. Preclinical SPECT/CT imaging of mice with and without the predose was performed at 48 hours post-injection of labeled DTPA-INCA-X. Biodistribution of the labeled antibody showed enriched activity in tumor, spleen and liver. Animals pre-administered with DTPA-INCA-X showed increased tumor uptake and blood content of (111)In-DTPA-INCA-X with reduced splenic and liver uptake. The in vitro and in vivo data presented show that the (111)In-labeled INCA-X antibody is internalized into prostate cancer cells and by pre-administering non-labeled DTPA-INCA-X, we were able to significantly reduce the off target binding and increase the (111)In-DTPA-INCA-X mAb uptake in PC-3, PC-3M-Lu2 and DU145 xenografts. The results are encouraging and identifying the Ku70/Ku80 antigen as a target is worth further investigation for functional imaging of prostate cancer.
Collapse
Affiliation(s)
- Susan Evans-Axelsson
- Division of Urological Cancers, Department of Clinical Sciences Malmö, Lund UniversitySweden
| | | | | | - Carl AK Borrebaeck
- Department of Immunotechnology and CREATE Health Translational Cancer Center, Lund UniversityMedicon Village, Lund, Sweden
| | - Sven-Erik Strand
- Department of Medical Radiation Physics, Clinical Sciences, Lund UniversityLund, Sweden
- Lund University Bioimaging CenterLund, Sweden
| | - Thuy A Tran
- Lund University Bioimaging CenterLund, Sweden
| | - Bo Jansson
- Department of Oncology, Clinical Sciences, Lund UniversityLund, Sweden
| | - Anders Bjartell
- Division of Urological Cancers, Department of Clinical Sciences Malmö, Lund UniversitySweden
| |
Collapse
|