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Fan M, Huang Y, Zhu X, Zheng J, Du M. Octreotide and Octreotide-derived delivery systems. J Drug Target 2023; 31:569-584. [PMID: 37211679 DOI: 10.1080/1061186x.2023.2216895] [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: 02/15/2023] [Revised: 04/01/2023] [Accepted: 04/29/2023] [Indexed: 05/23/2023]
Abstract
Pharmaceutical peptide Octreotide is a somatostatin analog with targeting and therapeutic abilities. Over the last decades, Octreotide has been developed and approved to treat acromegaly and neuroendocrine tumours, and Octreotide-based radioactive conjugates have been leveraged clinically to detect small neuroendocrine tumour sites. Meanwhile, variety of Octreotide-derived delivery strategies have been proposed and explored for tumour targeted therapeutics or diagnostics in preclinical or clinical settings. In this review, we especially focus on the preclinical development and applications of Octreotide-derived drug delivery systems, diagnostic nanosystems, therapeutic nanosystems and multifunctional nanosystems, we also briefly discuss challenges and prospects of these Octreotide-derived delivery systems.
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Affiliation(s)
- Mingliang Fan
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, China
| | - Yue Huang
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, China
| | - Xinlin Zhu
- Department of Dermatology, Shanghai Key Laboratory of Medical Mycology, Changzheng Hospital, Naval Medical University, Shanghai, China
| | - Jiayu Zheng
- School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, China
| | - Mingwei Du
- Department of Dermatology, Shanghai Key Laboratory of Medical Mycology, Changzheng Hospital, Naval Medical University, Shanghai, China
- Department of Cardiology, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai Key Laboratory of Traditional Chinese Clinical Medicine, Shanghai, China
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2
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Meyer JP, Tully KM, Jackson J, Dilling TR, Reiner T, Lewis JS. Bioorthogonal Masking of Circulating Antibody-TCO Groups Using Tetrazine-Functionalized Dextran Polymers. Bioconjug Chem 2018; 29:538-545. [PMID: 29378403 DOI: 10.1021/acs.bioconjchem.8b00028] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Pretargeting strategies have gained popularity for the in vivo imaging and therapy of cancer by combining antibodies with small molecule radioligands. In vivo recombination of both moieties can be achieved using the bioorthogonal inverse electron demand Diels-Alder (IEDDA) chemistry between tetrazine (Tz) and trans-cyclooctene (TCO). An issue that arises with pretargeting strategies is that while part of the antibody dose accumulates at antigen-expressing tumor tissue, there is a significant portion of the injected antibody that remains in circulation, causing a reduction in target-to-background ratios. Herein, we report the development of a novel TCO scavenger, the masking agent DP-Tz. DP-Tz is based on Tz-modified dextran polymers (DP, MW = 0.5-2 MDa). Large dextran polymers were reported to exhibit low penetration of tumor vasculature and appeared nontoxic, nonimmunogenic, and easily modifiable. Our newly developed masking agent deactivates the remaining TCO-moieties on the circulating mAbs yet does not impact the tumor uptake of the Tz-radioligand. In pretargeting studies utilizing a 68Ga-labeled tetrazine radioligand ([68Ga]Ga-NOTA-PEG11-tetrazine), DP-Tz constructs (Tz/DP ratios of 62-254) significantly increased TTB ratios from 0.8 ± 0.3 (control cohorts) to up to 5.8 ± 2.3 at 2 h postinjection. Tumor tissue delineation in PET imaging experiments employing DP-Tz is significantly increased compared to control. Uptake values of other significant organs, such as heart, lungs, pancreas, and stomach, were decreased on average by 2-fold when using DP-Tz. Overall, pretargeting experiments utilizing DP-Tz showed significantly improved tumor delineation, enhanced PET image quality, and reduced uptake in vital organs. We believe that this new masking agent is a powerful new addition to the IEDDA-based pretargeting tool box and, due to its properties, an excellent candidate for clinical translation.
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Affiliation(s)
- Jan-Philip Meyer
- Department of Radiology and ∥Program in Molecular Pharmacology, Memorial Sloan Kettering Cancer Center , 1275 York Avenue, New York, New York 10065, United States.,Department of Pharmacology and §Department of Radiology, Weill Cornell Medical College , 1300 York Avenue, New York, New York 10065, United States
| | - Kathryn M Tully
- Department of Radiology and ∥Program in Molecular Pharmacology, Memorial Sloan Kettering Cancer Center , 1275 York Avenue, New York, New York 10065, United States.,Department of Pharmacology and §Department of Radiology, Weill Cornell Medical College , 1300 York Avenue, New York, New York 10065, United States
| | - James Jackson
- Department of Radiology and ∥Program in Molecular Pharmacology, Memorial Sloan Kettering Cancer Center , 1275 York Avenue, New York, New York 10065, United States.,Department of Pharmacology and §Department of Radiology, Weill Cornell Medical College , 1300 York Avenue, New York, New York 10065, United States
| | - Thomas R Dilling
- Department of Radiology and ∥Program in Molecular Pharmacology, Memorial Sloan Kettering Cancer Center , 1275 York Avenue, New York, New York 10065, United States.,Department of Pharmacology and §Department of Radiology, Weill Cornell Medical College , 1300 York Avenue, New York, New York 10065, United States
| | - Thomas Reiner
- Department of Radiology and ∥Program in Molecular Pharmacology, Memorial Sloan Kettering Cancer Center , 1275 York Avenue, New York, New York 10065, United States.,Department of Pharmacology and §Department of Radiology, Weill Cornell Medical College , 1300 York Avenue, New York, New York 10065, United States
| | - Jason S Lewis
- Department of Radiology and ∥Program in Molecular Pharmacology, Memorial Sloan Kettering Cancer Center , 1275 York Avenue, New York, New York 10065, United States.,Department of Pharmacology and §Department of Radiology, Weill Cornell Medical College , 1300 York Avenue, New York, New York 10065, United States
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Pant K, Sedláček O, Nadar RA, Hrubý M, Stephan H. Radiolabelled Polymeric Materials for Imaging and Treatment of Cancer: Quo Vadis? Adv Healthc Mater 2017; 6. [PMID: 28218487 DOI: 10.1002/adhm.201601115] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 11/24/2016] [Indexed: 12/15/2022]
Abstract
Owing to their tunable blood circulation time and suitable plasma stability, polymer-based nanomaterials hold a great potential for designing and utilising multifunctional nanocarriers for efficient imaging and effective treatment of cancer. When tagged with appropriate radionuclides, they may allow for specific detection (diagnosis) as well as the destruction of tumours (therapy) or even customization of materials, aiming to both diagnosis and therapy (theranostic approach). This review provides an overview of recent developments of radiolabelled polymeric nanomaterials (natural and synthetic polymers) for molecular imaging of cancer, specifically, applying nuclear techniques such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT). Different approaches to radiolabel polymers are evaluated from the methodical radiochemical point of view. This includes new bifunctional chelating agents (BFCAs) for radiometals as well as novel labelling methods. Special emphasis is given to eligible strategies employed to evade the mononuclear phagocytic system (MPS) in view of efficient targeting. The discussion encompasses promising strategies currently employed as well as emerging possibilities in radionuclide-based cancer therapy. Key issues involved in the clinical translation of radiolabelled polymers and future scopes of this intriguing research field are also discussed.
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Affiliation(s)
- Kritee Pant
- Helmholtz-Zentrum Dresden-Rossendorf; Institute of Radiopharmaceutical Cancer Research; Bautzner Landstraße 400 01328 Dresden Germany
| | - Ondřej Sedláček
- Institute of Macromolecular Chemistry; The Academy of Sciences of the Czech Republic; Heyrovského námeˇstí 2 16206 Prague 6 Czech Republic
| | - Robin A. Nadar
- Helmholtz-Zentrum Dresden-Rossendorf; Institute of Radiopharmaceutical Cancer Research; Bautzner Landstraße 400 01328 Dresden Germany
| | - Martin Hrubý
- Institute of Macromolecular Chemistry; The Academy of Sciences of the Czech Republic; Heyrovského námeˇstí 2 16206 Prague 6 Czech Republic
| | - Holger Stephan
- Helmholtz-Zentrum Dresden-Rossendorf; Institute of Radiopharmaceutical Cancer Research; Bautzner Landstraße 400 01328 Dresden Germany
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van Witteloostuijn SB, Pedersen SL, Jensen KJ. Half-Life Extension of Biopharmaceuticals using Chemical Methods: Alternatives to PEGylation. ChemMedChem 2016; 11:2474-2495. [DOI: 10.1002/cmdc.201600374] [Citation(s) in RCA: 126] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 09/24/2016] [Indexed: 12/21/2022]
Affiliation(s)
- Søren B. van Witteloostuijn
- Department of Chemistry; University of Copenhagen; Thorvaldsensvej 40 1871 Frederiksberg C Denmark
- Gubra ApS; Hørsholm Kongevej 11B 2970 Hørsholm Denmark
| | | | - Knud J. Jensen
- Department of Chemistry; University of Copenhagen; Thorvaldsensvej 40 1871 Frederiksberg C Denmark
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Guo Z, Xing Z, Cheng X, Fang Z, Jiang C, Su J, Zhou Z, Xu Z, Holmberg A, Nilsson S, Liu Z. Somatostatin Derivate (smsDX) Attenuates the TAM-Stimulated Proliferation, Migration and Invasion of Prostate Cancer via NF-κB Regulation. PLoS One 2015; 10:e0124292. [PMID: 26010447 PMCID: PMC4444263 DOI: 10.1371/journal.pone.0124292] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Accepted: 03/12/2015] [Indexed: 01/08/2023] Open
Abstract
Tumor development and progression are influenced by macrophages of the surrounding microenvironment. To investigate the influences of an inflammatory tumor microenvironment on the growth and metastasis of prostate cancer, the present study used a co-culture model of prostate cancer (PCa) cells with tumor-associated macrophage (TAM)-conditioned medium (MCM). MCM promoted PCa cell (LNCaP, DU145 and PC-3) growth, and a xenograft model in nude mice consistently demonstrated that MCM could promote tumor growth. MCM also stimulated migration and invasion in vitro. Somatostatin derivate (smsDX) significantly attenuated the TAM-stimulated proliferation, migration and invasion of prostate cancer. Immunohistochemistry revealed that NF-κB was over-expressed in PCa and BPH with chronic inflammatory tissue specimens and was positively correlated with macrophage infiltration. Further investigation into the underlying mechanism revealed that NF-κB played an important role in macrophage infiltration. SmsDX inhibited the paracrine loop between TAM and PCa cells and may represent a potential therapeutic agent for PCa.
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Affiliation(s)
- Zhaoxin Guo
- Department of Urology, Qilu Hospital of Shandong University, Jinan, Shandong, China
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Public Health, Department of Cardiology, Qilu Hospital of Shandong University, Ji’nan, Shandong, China
| | - Zhaoquan Xing
- Department of Urology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Xiangyu Cheng
- Department of Urology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Zhiqing Fang
- Department of Urology, Qilu Hospital of Shandong University, Jinan, Shandong, China
- The Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Public Health, Department of Cardiology, Qilu Hospital of Shandong University, Ji’nan, Shandong, China
| | - Chao Jiang
- Department of Urology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Jing Su
- School of Nursing, Shandong University, Jinan, Shandong, China
| | - Zunlin Zhou
- Department of Urology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Zhonghua Xu
- Department of Urology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Anders Holmberg
- Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Sten Nilsson
- Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden
| | - Zhaoxu Liu
- Department of Urology, Qilu Hospital of Shandong University, Jinan, Shandong, China
- School of Nursing, Shandong University, Jinan, Shandong, China
- Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden
- * E-mail:
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Janib SM, Gustafson JA, Minea RO, Swenson SD, Liu S, Pastuszka MK, Lock LL, Cui H, Markland FS, Conti PS, Li Z, MacKay JA. Multimeric disintegrin protein polymer fusions that target tumor vasculature. Biomacromolecules 2014; 15:2347-58. [PMID: 24871936 PMCID: PMC4098058 DOI: 10.1021/bm401622y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
![]()
Recombinant protein therapeutics
have increased in number and frequency
since the introduction of human insulin, 25 years ago. Presently,
proteins and peptides are commonly used in the clinic. However, the
incorporation of peptides into clinically approved nanomedicines has
been limited. Reasons for this include the challenges of decorating
pharmaceutical-grade nanoparticles with proteins by a process that
is robust, scalable, and cost-effective. As an alternative to covalent
bioconjugation between a protein and nanoparticle, we report that
biologically active proteins may themselves mediate the formation
of small multimers through steric stabilization by large protein polymers.
Unlike multistep purification and bioconjugation, this approach is
completed during biosynthesis. As proof-of-principle, the disintegrin
protein called vicrostatin (VCN) was fused to an elastin-like polypeptide
(A192). A significant fraction of fusion proteins self-assembled into
multimers with a hydrodynamic radius of 15.9 nm. The A192-VCN fusion
proteins compete specifically for cell-surface integrins on human
umbilical vein endothelial cells (HUVECs) and two breast cancer cell
lines, MDA-MB-231 and MDA-MB-435. Confocal microscopy revealed that,
unlike linear RGD-containing protein polymers, the disintegrin fusion
protein undergoes rapid cellular internalization. To explore their
potential clinical applications, fusion proteins were characterized
using small animal positron emission tomography (microPET). Passive
tumor accumulation was observed for control protein polymers; however,
the tumor accumulation of A192-VCN was saturable, which is consistent
with integrin-mediated binding. The fusion of a protein polymer and
disintegrin results in a higher intratumoral contrast compared to
free VCN or A192 alone. Given the diversity of disintegrin proteins
with specificity for various cell-surface integrins, disintegrin fusions
are a new source of biomaterials with potential diagnostic and therapeutic
applications.
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Affiliation(s)
- Siti M Janib
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, §Medical Technology Division, Malaysian Nuclear Agency, Bangi, 43000 Kajang Selangor, Malaysia
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7
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Mier W, Krämer S, Zitzmann S, Altmann A, Leotta K, Schierbaum U, Schnölzer M, Eisenhut M, Haberkorn U. PEGylation enables the specific tumor accumulation of a peptide identified by phage display. Org Biomol Chem 2013; 11:2706-11. [DOI: 10.1039/c3ob27475f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Salehpour M, Håkansson K, Höglund U, Grahn-Westin A, Nilsson S, Márquez M, Possnert G, Holmberg AR. Application of accelerator mass spectrometry to macromolecules: preclinical pharmacokinetic studies on a polybisphosphonate. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2011; 25:2453-2458. [PMID: 21818805 DOI: 10.1002/rcm.5149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Data on the use of accelerator mass spectrometry (AMS) in conjunction with in vivo studies of macromolecular drugs are scarce. The present study shows the versatility of this technique when investigating the pharmacokinetics (PK) of a macromolecular drug candidate, a polybisphosphonate conjugate (ODX). The aforementioned is a polymer (molecular weight ~30 kDa) constituting a carbohydrate backbone with covalently linked ligands (aldendronate and aminoguanidine) and is intended for treatment of osteoporosis and the therapy of bone metastasis from prostate cancer. The conjugate is prepared through partial oxidation of the carbohydrate and sequential coupling of the ligands by reductive amination. (14)C was incorporated in the conjugate by means of coupling a commercially available (14)C-lysine in the conjugation sequence. Fifteen rats were injected intravenously with (14)C-labelled ODX (150 µg, 14 Bq/rat) and blood samples were collected at 1, 2, 4, 6, and 24 h post-injection (3 rats/time point). Liver, spleen and kidney samples were collected at 4 and 24 h post-injection. Blood from each time point (triplicate) were collected for AMS measurement determining the isotopic ratio ((14)C/(12)C) and consequently the drug concentration in blood. ODX showed a transient presence in blood circulation; 93% of the total dose was cleared from the circulation within 1 h. The half-life after 1 h was estimated to be about 3 h; 0.7% of the administered (14)C dose of ODX remained in circulation after 24 h. The major (14)C accumulation was in the liver, the spleen and the kidneys indicating the probable route of metabolism and excretion. This study demonstrates the versatility of AMS for pharmacological in vivo studies of macromolecules. Labelling with (14)C is relatively simple, inexpensive and the method requires minimal radioactivity, eliminating the need for radioprotection precautions in contrast to methods using scintillation counting.
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Affiliation(s)
- Mehran Salehpour
- Ion Physics, Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden.
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9
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Núñez EGF, Teodoro R, Wiecek DP, da Silva NG, Martinelli JR, de Oliveira Filho RS. Size and specificity of radiopharmaceuticals for sentinel lymph node detection. Acta Radiol 2011; 52:774-8. [PMID: 21558148 DOI: 10.1258/ar.2011.100506] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND Biological performance of radiotracers for sentinel node detection analyzed in the light of molecular design and dimension is not widely available. PURPOSE To evaluate the effect of dextran molecular size and the presence of tissue-binding units (mannose) within the model of (99m)Tc-carbonyl conjugate for sentinel lymph node detection. MATERIAL AND METHODS Four dextran conjugates with and without mannose in the chemical backbone were included. All polymers were radiolabeled using the precursor [(99m)Tc(OH(2))(3)(CO)(3)](+). Radiolabeling conditions targeted the best radiochemical purity and specific activity for each radiopharmaceutical, and partition coefficients were also defined. Lymphoscintigraphy and ex-vivo biodistribution in popliteal lymph node, liver and kidneys were performed in Wistar rats. The effects of molecular weight and mannose presence were assessed by a two-level factorial design. RESULTS Radiochemical purity was indirectly related to molecular weight and presence of mannose in the polymer structure. All products were able to detect popliteal lymph node, however, uptake was strongly influenced by use of mannose (4-fold higher). Excretion was similarly modulated by differences in molecular weight. Mannose-enhanced lymph node uptake and higher molecule size in the range under study benefitted lymphoscintigraphic performance. CONCLUSION Screening of radiopharmaceuticals for lymphoscintigraphy might improve with attention to the mentioned physico-chemical features of the molecule.
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Affiliation(s)
| | | | | | - Natanael Gomes da Silva
- Center of Materials Science and Technology, Institute of Energetic and Nuclear Research, Sao Paulo
| | - Jose Roberto Martinelli
- Center of Materials Science and Technology, Institute of Energetic and Nuclear Research, Sao Paulo
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Liu W, Dreher MR, Furgeson DY, Peixoto KV, Yuan H, Zalutsky MR, Chilkoti A. Tumor accumulation, degradation and pharmacokinetics of elastin-like polypeptides in nude mice. J Control Release 2006; 116:170-8. [PMID: 16919353 DOI: 10.1016/j.jconrel.2006.06.026] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2006] [Revised: 06/16/2006] [Accepted: 06/21/2006] [Indexed: 10/24/2022]
Abstract
ELPs are genetically engineered, thermally responsive polypeptides that preferentially accumulate in solid tumors subjected to focused, mild hyperthermia. In this paper, we report the biodegradation, pharmacokinetics, tumor localization, and tumor spatial distribution of (14)C-labeled ELPs that were radiolabeled during their biosynthesis in Escheriehia coli. The in vitro degradation rate of a thermally responsive (14)C-labeled ELP1 ([(14)C] ELP1) with a molecular weight of 59.4 kDa, upon exposure to murine serum, was 2.49 wt.%/day. The apparent in vivo degradation rate of ELP1 after intravenous injection of nude mice was 2.46 wt.%/day and its terminal half-life was 8.7 h. The tumor accumulation and spatial distribution of intravenously administered ELP1 and a control ELP that was designed to remain soluble in heated tumors (ELP2) were examined in both heated (41.5 degrees C) and unheated tumors. ELP1 accumulated at a significantly higher concentration in heated tumors than ELP1 in unheated tumors and ELP2 in heated tumors. Quantitative autoradiography of tumor sections provided similar tumor accumulation results as the whole tumor analysis but, in addition, showed that ELP1 had a more homogeneous distribution in heated tumors and a greater concentration in the tumor center than either control treatment.
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Affiliation(s)
- Wenge Liu
- Department of Biomedical Engineering, Duke University, Box 90281, Durham, NC 27708, USA
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Carlsson J, Kullberg EB, Capala J, Sjöberg S, Edwards K, Gedda L. Ligand liposomes and boron neutron capture therapy. J Neurooncol 2003; 62:47-59. [PMID: 12749702 DOI: 10.1007/bf02699933] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Boron neutron capture therapy (BNCT) has been used both experimentally and clinically for the treatment of gliomas and melanomas, with varying results. However, the therapeutic effects on micro-invasive tumor cells are not clear. The two drugs that have been used clinically, p-boronophenylalanine, (BPA), and the sulfhydryl borane, (BSH), seem to be taken up preferentially in solid tumor areas but it is uncertain whether enough boron is taken up by micro-invasive tumor cells. To increase the selective uptake of boron by such cells, would be to exploit tumor transformation related cellular changes such as over-expression of growth factor receptors. However, the number of receptors varies from small to large and the uptake of large amounts of boron for each receptor interaction is necessary in order to deliver sufficient amounts of boron. Therefore, each targeting moiety must deliver large number of boron atoms. One possible way to meet these requirements would be to use receptor-targeting ligand liposomes, containing large number of boron atoms. This will be the subject of this review and studies of boron containing liposomes, with or without ligand, will be discussed. Two recent examples from the literature are ligand liposomes targeting either folate or epidermal growth factor (EGF) receptors on tumor cells. Other potential receptors on gliomas include PDGFR and EGFRvIII. Besides the appropriate choice of target receptor, it is also important to consider delivery of the ligand liposomes, their pharmacodynamics and pharmacokinetics and cellular processing, subjects that also will be discussed in this review.
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Affiliation(s)
- Jörgen Carlsson
- Biomedical Radiation Sciences, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden.
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Carlsson J, Forssell Aronsson E, Hietala SO, Stigbrand T, Tennvall J. Tumour therapy with radionuclides: assessment of progress and problems. Radiother Oncol 2003; 66:107-17. [PMID: 12648782 DOI: 10.1016/s0167-8140(02)00374-2] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Radionuclide therapy is a promising modality for treatment of tumours of haematopoietic origin while the success for treatment of solid tumours so far has been limited. The authors consider radionuclide therapy mainly as a method to eradicate disseminated tumour cells and small metastases while bulky tumours and large metastases have to be treated surgically or by external radiation therapy. The promising therapeutic results for haematological tumours give hope that radionuclide therapy will have a breakthrough also for treatment of disseminated cells from solid tumours. New knowledge related to this is continuously emerging since new molecular target structures are being characterised and the knowledge on pharmacokinetics and cellular processing of different types of targeting agents increases. There is also improved understanding of the factors of importance for the choice of appropriate radionuclides with respect to their decay properties and the therapeutic applications. Furthermore, new methods to modify the uptake of radionuclides in tumour cells and normal tissues are emerging. However, we still need improvements regarding dosimetry and treatment planning as well as an increased knowledge about the tolerance doses for normal tissues and the radiobiological effects on tumour cells. This is especially important in targeted radionuclide therapy where the dose rates often are lower than 1Gy/h.
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Affiliation(s)
- Jörgen Carlsson
- Department of Oncology, Radiology and Clinical Oncology, Uppsala University Hospital, SE-751 85 Uppsala, Sweden
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