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Bridgwater C, Geller A, Hu X, Burlison JA, Zhang HG, Yan J, Guo H. 89Zr-Labeled Anti-PD-L1 Antibody Fragment for Evaluating In Vivo PD-L1 Levels in Melanoma Mouse Model. Cancer Biother Radiopharm 2020; 35:549-557. [PMID: 32315549 DOI: 10.1089/cbr.2019.3056] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The rise of programmed death-1 (PD-1)/PD-L1 immune checkpoint inhibitor therapy has been one of the most promising developments in melanoma research. However, not all the melanoma patients respond to such immune checkpoint blockade. There is a great need of biomarkers for appropriate melanoma patient selection and therapeutic efficacy monitoring. The objective of this study is to develop a novel radiolabeled anti-PD-L1 antibody fragment, as an imaging biomarker, for evaluating the in vivo PD-L1 levels in melanoma. The Df-conjugated F(ab')2 fragment of the anti-mouse PD-L1 antibody was successfully synthesized and radiolabeled with 89Zr. Both Df-F(ab')2 and 89Zr-Df-F(ab')2 maintained the nano-molar murine PD-L1 targeting specificity and affinity. 89Zr-Df-F(ab')2 showed less uptake in normal liver tissue in mice compared with its full antibody counterpart 89Zr-Df-anti-PD-L1. Positron emission tomography (PET)/computed tomography images clearly showed that 89Zr-Df-F(ab')2 possessed superior pharmacokinetics and imaging contrast over the radiolabeled full antibody, with much earlier and higher tumor uptake (5.5 times more at 2 h post injection) and much lower liver background (51% reduction at 2 h post injection). The specific and high murine PD-L1-targeting uptake at tumor foci coupled with fast clearance of 89Zr-Df-F(ab')2 highlighted its potential for in vivo PET imaging of murine PD-L1 levels and future development of radiolabeled anti-human PD-L1 fragment for potential application in melanoma patients.
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Affiliation(s)
- Caleb Bridgwater
- Department of Radiology, University of Louisville, Louisville, Kentucky, USA
| | - Anne Geller
- Department of Microbiology and Immunology, University of Louisville, Louisville, Kentucky, USA
| | - Xiaoling Hu
- James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky, USA
| | - Joe A Burlison
- James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky, USA
| | - Huang-Ge Zhang
- Department of Microbiology and Immunology, University of Louisville, Louisville, Kentucky, USA.,James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky, USA
| | - Jun Yan
- Department of Microbiology and Immunology, University of Louisville, Louisville, Kentucky, USA.,James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky, USA.,Department of Surgery, University of Louisville, Louisville, Kentucky, USA
| | - Haixun Guo
- Department of Radiology, University of Louisville, Louisville, Kentucky, USA.,Center for Predictive Medicine, University of Louisville, Louisville, Kentucky, USA
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Gao F, Sihver W, Bergmann R, Walther M, Stephan H, Belter B, Neuber C, Haase-Kohn C, Bolzati C, Pietzsch J, Pietzsch HJ. Radiochemical and radiopharmacological characterization of a 64 Cu-labeled α-MSH analog conjugated with different chelators. J Labelled Comp Radiopharm 2019; 62:495-509. [PMID: 30912594 DOI: 10.1002/jlcr.3728] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 03/01/2019] [Accepted: 03/08/2019] [Indexed: 02/06/2023]
Abstract
Radiolabeled α-melanocyte-stimulating hormone (α-MSH) derivatives have a high potential for diagnosis and treatment of melanoma, because of high specificity and binding affinity to the melanocortin-1 receptor (MC1R). Hence, the α-MSH-derived peptide NAP-NS1 with a β-Ala linker (ε-Ahx-β-Ala-Nle-Asp-His-D-Phe-Arg-Trp-Gly-NH2 ) was conjugated to different chelators: either to NOTA (p-SCN-Bn-1,4,7-triazacyclononane-1,4,7-triacetic acid), to a hexadentate bispidine carbonate derivative (dimethyl-9-(((4-nitrophenoxy)carbonyl)oxy)-2,4-di(pyridin-2-yl)-3,7-bis(pyridin-2-ylmethyl)-3,7-diazabicyclo[3.3.1]nonane-1,5-dicarboxylate), or to DMPTACN (p-SCN-Ph-bis(2-pyridyl-methyl)-1,4,7-triaza-cyclononane), labeled with 64 Cu, and investigated in terms of radiochemical and radiopharmacological properties. For the three 64 Cu-labeled conjugates negligible transchelation, suitable buffer and serum stability, as well as appropriate water solubility, was determined. The three conjugates exhibited high binding affinity (low nanomolar range) in murine B16F10, human MeWo, and human TXM13 cells. The Bmax values of [64 Cu]Cu-bispidine-NAP-NS1 ([64 Cu]Cu-2) and [64 Cu]Cu-DMPTACN-NAP-NS1 ([64 Cu]Cu-3) were higher than those of [64 Cu]Cu-NOTA-NAP-NS1 ([64 Cu]Cu-1), implying that different charged chelate units might have an impact on binding capacity. Preliminary in vivo biodistribution studies suggested the main excretion pathway of [64 Cu]Cu-1 and [64 Cu]Cu-3 to be renal, while that of [64 Cu]Cu-2 seemed to be both renal and hepatobiliary. An initial moderate uptake in the kidney decreased clearly after 60 minutes. All three 64 Cu-labeled conjugates should be considered for further in vivo investigations using a suitable xenograft mouse model.
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Affiliation(s)
- Feng Gao
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.,School of Science, Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Dresden, Germany
| | - Wiebke Sihver
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Ralf Bergmann
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Martin Walther
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Holger Stephan
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Birgit Belter
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Christin Neuber
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Cathleen Haase-Kohn
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Cristina Bolzati
- Italian National Research Council - CNR, Institute of Condensed Matter Chemistry and Energy Technologies ICMATE-CNR, Padova, Italy
| | - Jens Pietzsch
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.,School of Science, Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Dresden, Germany
| | - Hans-Jürgen Pietzsch
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.,School of Science, Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Dresden, Germany
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Guarracino DA, Riordan JA, Barreto GM, Oldfield AL, Kouba CM, Agrinsoni D. Macrocyclic Control in Helix Mimetics. Chem Rev 2019; 119:9915-9949. [DOI: 10.1021/acs.chemrev.8b00623] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Danielle A. Guarracino
- Department of Chemistry, The College of New Jersey, Ewing, New Jersey 08628, United States
| | - Jacob A. Riordan
- Department of Chemistry, The College of New Jersey, Ewing, New Jersey 08628, United States
| | - Gianna M. Barreto
- Department of Chemistry, The College of New Jersey, Ewing, New Jersey 08628, United States
| | - Alexis L. Oldfield
- Department of Chemistry, The College of New Jersey, Ewing, New Jersey 08628, United States
| | - Christopher M. Kouba
- Department of Chemistry, The College of New Jersey, Ewing, New Jersey 08628, United States
| | - Desiree Agrinsoni
- Department of Chemistry, The College of New Jersey, Ewing, New Jersey 08628, United States
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Bapst JP, Eberle AN. Receptor-Mediated Melanoma Targeting with Radiolabeled α-Melanocyte-Stimulating Hormone: Relevance of the Net Charge of the Ligand. Front Endocrinol (Lausanne) 2017; 8:93. [PMID: 28491052 PMCID: PMC5405074 DOI: 10.3389/fendo.2017.00093] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 04/10/2017] [Indexed: 12/03/2022] Open
Abstract
A majority of melanotic and amelanotic melanomas overexpress melanocortin type 1 receptors (MC1Rs) for α-melanocyte-stimulating hormone. Radiolabeled linear or cyclic analogs of α-MSH have a great potential as diagnostic or therapeutic tools for the management of malignant melanoma. Compounds such as [111In]DOTA-NAP-amide exhibit high affinity for the MC1R in vitro, good tumor uptake in vivo, but they may suffer from relatively high kidney uptake and retention in vivo. We have shown previously that the introduction of negative charges into radiolabeled DOTA-NAP-amide peptide analogs may enhance their excretion and reduce kidney retention. To address the question of where to place negative charges within the ligand, we have extended these studies by designing two novel peptides, Ac-Nle-Asp-His-d-Phe-Arg-Trp-Gly-Lys(DOTA)-d-Asp-d-Asp-OH (DOTA-NAP-d-Asp-d-Asp) with three negative charges at the C-terminal end (overall net charge of the molecule -2) and DOTA-Gly-Tyr(P)-Nle-Asp-His-d-Phe-Arg-Trp-NH2 (DOTA-Phospho-MSH2-9) with two negative charges in the N-terminal region (net charge -1). The former peptide showed markedly reduced receptor affinity and biological activity by >10-fold compared to DOTA-NAP-amide as reference compound, and the latter peptide displayed similar bioactivity and receptor affinity as the reference compound. The uptake by melanoma tumor tissue of [111In]DOTA-Phospho-MSH2-9 was 7.33 ± 0.47 %ID/g 4 h after injection, i.e., almost equally high as with [111In]DOTA-NAP-amide. The kidney retention was 2.68 ± 0.18 %ID/g 4 h after injection and hence 44% lower than that of [111In]DOTA-NAP-amide. Over an observation period from 4 to 48 h, the tumor-to-kidney ratio of [111In]DOTA-Phospho-MSH2-9 was 35% more favorable than that of the reference compound. In a comparison of DOTA-NAP-d-Asp-d-Asp, DOTA-Phospho-MSH2-9 and DOTA-NAP-amide with five previously published analogs of DOTA-NAP-amide that altogether cover a range of peptides with an overall net charge between +2 and -2, we now demonstrate that a net charge of -1, with the extra negative charges preferably placed in the N-terminal region, has led to the lowest kidney uptake and retention. Charges of +2 or -2 markedly increased kidney uptake and retention. In conclusion, the novel DOTA-Phospho-MSH2-9 may represent a new lead compound for negatively charged linear MC1R ligands that can be further developed into a clinically relevant melanoma targeting radiopeptide.
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Affiliation(s)
- Jean-Philippe Bapst
- Laboratory of Endocrinology, Department of Biomedicine, University Hospital and University Children’s Hospital, University of Basel, Basel, Switzerland
| | - Alex N. Eberle
- Laboratory of Endocrinology, Department of Biomedicine, University Hospital and University Children’s Hospital, University of Basel, Basel, Switzerland
- Collegium Helveticum, ETH Zurich, Zurich, Switzerland
- *Correspondence: Alex N. Eberle,
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Carta D, Salvarese N, Morellato N, Gao F, Sihver W, Pietzsch HJ, Biondi B, Ruzza P, Refosco F, Carpanese D, Rosato A, Bolzati C. Melanoma targeting with [ 99mTc(N)(PNP3)]-labeled α-melanocyte stimulating hormone peptide analogs: Effects of cyclization on the radiopharmaceutical properties. Nucl Med Biol 2016; 43:788-801. [PMID: 27694057 DOI: 10.1016/j.nucmedbio.2016.08.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 08/23/2016] [Accepted: 08/26/2016] [Indexed: 11/16/2022]
Abstract
The purpose of this study was to evaluate the effect of cyclization on the biological profile of a [99mTc(N)(PNP3)]-labeled α-melanocyte stimulating hormone peptide analog. A lactam bridge-cyclized H-Cys-Ahx-βAla3-c[Lys4-Glu-His-D-Phe-Arg-Trp-Glu10]-Arg11-Pro-Val-NH2 (NAP-NS2) and the corresponding linear H-Cys-Ahx-βAla-Nle-Asp-His-D-Phe-Arg-Trp-Gly-NH2 (NAP-NS1) peptide were synthetized, characterized by ESI-MS spectroscopy and their melanocortin-1 receptor (MC1R) binding affinity was determined in B16/F10 melanoma cells. The consistent [99mTc(N)(PNP3)]-labeled compounds were readily obtained in high specific activity and their stability and biological properties were assessed. As an example, the chemical identity of [99mTc(N)(NAP-NS1)(PNP3)]+ was confirmed by carrier added experiments supported by radio/UV HPLC analysis combined with ESI(+)-MS. Compared with the linear peptide, cyclization negatively affected the biological properties of NAP-NS2 peptide by reducing its binding affinity for MC1R and by decreasing the overall excretion rate of the corresponding [99mTc(N)(PNP3)]-labeled peptide from the body as well as its in vivo stability. [99mTc(N)(NAP-NS1)(PNP3)]+ was evaluated for its potential as melanoma imaging probe in murine melanoma model. Data from in vitro and in vivo studies on B16/F10 melanoma model of [99mTc(N)(NAP-NS1)(PNP3)]+ clearly evidenced that the radiolabeled linear peptide keeps its biological properties up on the conjugation to the [99mTc(N)(PNP3)]-building block. The progressive increase of the tumor-to-nontarget ratios over the time indicates a quite stable interaction between the radio-complex and the MC1R.
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Affiliation(s)
- Davide Carta
- Dipartimento di Scienze del Farmaco, University of Padova, Via Marzolo 5, 35131 Padova, Italy
| | | | - Nicolò Morellato
- Dipartimento di Scienze del Farmaco, University of Padova, Via Marzolo 5, 35131 Padova, Italy
| | - Feng Gao
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstrasse 400, 01328, Dresden, Germany
| | - Wiebke Sihver
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstrasse 400, 01328, Dresden, Germany
| | - Hans Jurgen Pietzsch
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstrasse 400, 01328, Dresden, Germany
| | | | | | | | - Debora Carpanese
- Dipartimento di Scienze Chirurgiche, Oncologiche e Gastroenterologiche, University of Padova, Via Gattamelata, 64, 35138 Padova
| | - Antonio Rosato
- Dipartimento di Scienze Chirurgiche, Oncologiche e Gastroenterologiche, University of Padova, Via Gattamelata, 64, 35138 Padova,; Istituto Oncologico Veneto IOV-IRCCS, Via Gattamelata, 64, 35128 Padova, Italy
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Gao F, Sihver W, Jurischka C, Bergmann R, Haase-Kohn C, Mosch B, Steinbach J, Carta D, Bolzati C, Calderan A, Pietzsch J, Pietzsch HJ. Radiopharmacological characterization of ⁶⁴Cu-labeled α-MSH analogs for potential use in imaging of malignant melanoma. Amino Acids 2016; 48:833-847. [PMID: 26643502 DOI: 10.1007/s00726-015-2131-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 11/04/2015] [Indexed: 10/22/2022]
Abstract
The melanocortin-1 receptor (MC1R) plays an important role in melanoma growth, angiogenesis and metastasis, and is overexpressed in melanoma cells. α-Melanocyte stimulating hormone (α-MSH) and derivatives are known to bind with high affinity at this receptor that provides the potential for selective targeting of melanoma. In this study, one linear α-MSH-derived peptide Nle-Asp-His-D-Phe-Arg-Trp-Gly-NH2 (NAP-NS1) without linker and with εAhx-β-Ala linker, and a cyclic α-MSH derivative, [Lys-Glu-His-D-Phe-Arg-Trp-Glu]-Arg-Pro-Val-NH2 (NAP-NS2) with εAhx-β-Ala linker were conjugated with p-SCN-Bn-NOTA and labeled with (64)Cu. Radiochemical and radiopharmacological investigations were performed with regard to transchelation, stability, lipophilicity and in vitro binding assays as well as biodistribution in healthy rats. No transchelation reactions, but high metabolic stability and water solubility were demonstrated. The linear derivatives showed higher affinity than the cyclic one. [(64)Cu]Cu-NOTA-εAhx-β-Ala-NAP-NS1 ([(64)Cu]Cu-2) displayed rapid cellular association and dissociation in murine B16F10 cell homogenate. All [(64)Cu]Cu-labeled conjugates exhibited affinities in the low nanomolar range in B16F10. [(64)Cu]Cu-2 showed also high affinity in human MeWo and TXM13 cell homogenate. In vivo studies suggested that [(64)Cu]Cu-2 was stable, with about 85 % of intact peptide in rat plasma at 2 h p.i. Biodistribution confirmed the renal pathway as the major elimination route. The uptake of [(64)Cu]Cu-2 in the kidney was 5.9 % ID/g at 5 min p.i. and decreased to 2.0 % ID/g at 60 min p.i. Due to the prospective radiochemical and radiopharmacological properties of the linear α-MSH derivative [(64)Cu]Cu-2, this conjugate is a promising candidate for tracer development in human melanoma imaging.
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Affiliation(s)
- Feng Gao
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328, Dresden, Germany
- Department of Chemistry and Food Chemistry, Technische Universität Dresden, 01062, Dresden, Germany
| | - Wiebke Sihver
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328, Dresden, Germany.
| | - Christoph Jurischka
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328, Dresden, Germany
- Brandenburg University of Technology Cottbus-Senftenberg, Cottbus, Germany
| | - Ralf Bergmann
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328, Dresden, Germany
| | - Cathleen Haase-Kohn
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328, Dresden, Germany
| | - Birgit Mosch
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328, Dresden, Germany
| | - Jörg Steinbach
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328, Dresden, Germany
- Department of Chemistry and Food Chemistry, Technische Universität Dresden, 01062, Dresden, Germany
| | - Davide Carta
- Department of Pharmacological and Pharmaceutical Sciences, University of Padua, 35131, Padua, Italy
| | | | | | - Jens Pietzsch
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328, Dresden, Germany
- Department of Chemistry and Food Chemistry, Technische Universität Dresden, 01062, Dresden, Germany
| | - Hans-Jürgen Pietzsch
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstraße 400, 01328, Dresden, Germany
- Department of Chemistry and Food Chemistry, Technische Universität Dresden, 01062, Dresden, Germany
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Tc-99m-labeled RGD-conjugated alpha-melanocyte stimulating hormone hybrid peptides with reduced renal uptake. Amino Acids 2015; 47:813-23. [PMID: 25557051 DOI: 10.1007/s00726-014-1911-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Accepted: 12/24/2014] [Indexed: 10/24/2022]
Abstract
The purpose of this study was to examine whether the replacement of the positively-charged Lys or Arg linker with a neutral linker could reduce the renal uptake of Arg-Gly-Asp (RGD)-conjugated alpha-melanocyte stimulating hormone (α-MSH) hybrid peptide. The RGD motif {cyclic(Arg-Gly-Asp-DTyr-Asp)} was coupled to [Cys(3,4,10), D-Phe(7), Arg(11)]α-MSH3-13 {(Arg(11))CCMSH} through the neutral βAla or Ahx {aminohexanoic acid} linker (replacing the Lys or Arg linker) to generate novel RGD-βAla-(Arg(11))CCMSH and RGD-Ahx-(Arg(11))CCMSH hybrid peptides. The receptor-binding affinity and cytotoxicity of RGD-βAla-(Arg(11))CCMSH and RGD-Ahx-(Arg(11))CCMSH were determined in B16/F1 melanoma cells. The melanoma targeting and imaging properties of (99m)Tc-RGD-βAla-(Arg(11))CCMSH and (99m)Tc-RGD-Ahx-(Arg(11))CCMSH were determined in B16/F1 melanoma-bearing C57 mice. The replacement of the Lys or Arg linker with the βAla or Ahx linker retained nanomolar receptor-binding affinities and remarkable cytotoxicity of RGD-βAla-(Arg(11))CCMSH and RGD-Ahx-(Arg(11))CCMSH. The receptor-binding affinities of RGD-βAla-(Arg(11))CCMSH and RGD-Ahx-(Arg(11))CCMSH were 0.8 ± 0.05 and 1.3 ± 0.1 nM. Three-hour incubation with 0.1 µM of RGD-βAla-(Arg(11))CCMSH and RGD-Ahx-(Arg(11))CCMSH decreased the survival percentages of B16/F1 cells by 71 and 67 % as compared to the untreated control cells 5 days post the treatment. The replacement of the Arg linker with the βAla or Ahx linker reduced the non-specific renal uptake of (99m)Tc-RGD-βAla-(Arg(11))CCMSH and (99m)Tc-RGD-Ahx-(Arg(11))CCMSH by 62 and 61 % at 2 h post-injection. (99m)Tc-RGD-βAla-(Arg(11))CCMSH displayed higher melanoma uptake than (99m)Tc-RGD-Ahx-(Arg(11))CCMSH at 0.5, 2, 4, and 24 h post-injection. Enhanced tumor to kidney uptake ratio of (99m)Tc-RGD-βAla-(Arg(11))CCMSH warranted the further evaluation of (188)Re-labeled RGD-βAla-(Arg(11))CCMSH as a novel MC1 receptor-targeting therapeutic peptide for melanoma treatment in the future.
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Guo H, Miao Y. Introduction of an 8-aminooctanoic acid linker enhances uptake of 99mTc-labeled lactam bridge-cyclized α-MSH peptide in melanoma. J Nucl Med 2014; 55:2057-63. [PMID: 25453052 DOI: 10.2967/jnumed.114.145896] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED The purpose of this study was to examine the effects of amino acid, hydrocarbon, and polyethylene glycol (PEG) linkers on the melanoma targeting and imaging properties of (99m)Tc-labeled lactam bridge-cyclized HYNIC-linker-Nle-CycMSHhex (hydrazinonicotinamide-linker-Nle-c[Asp-His-DPhe-Arg-Trp-Lys]-CONH2) peptides. METHODS Four novel peptides (HYNIC-GGGNle-CycMSHhex, HYNIC-GSGNle-CycMSHhex, HYNIC-PEG2Nle-CycMSHhex, and HYNIC-AocNle-CycMSHhex) were designed and synthesized. The melanocortin-1 receptor binding affinities of the peptides were determined in B16/F1 melanoma cells. The biodistribution of (99m)Tc(ethylenediaminediacetic acid [EDDA])-HYNIC-GGGNle-CycMSHhex, (99m)Tc(EDDA)-HYNIC-GSGNle-CycMSHhex, (99m)Tc(EDDA)-HYNIC-PEG2Nle-CycMSHhex, and (99m)Tc(EDDA)-HYNIC-AocNle-CycMSHhex were determined in B16/F1 melanoma-bearing C57 mice at 2 h after injection to select a lead peptide for further evaluation. The melanoma targeting and imaging properties of (99m)Tc(EDDA)-HYNIC-AocNle-CycMSHhex were further examined because of its high melanoma uptake. RESULTS The inhibitory concentrations of 50% (IC50) for HYNIC-GGGNle-CycMSHhex, HYNIC-GSGNle-CycMSHhex, HYNIC-PEG2Nle-CycMSHhex, and HYNIC-AocNle-CycMSHhex were 0.7 ± 0.1, 0.8 ± 0.09, 0.4 ± 0.08, and 0.3 ± 0.06 nM, respectively, in B16/F1 melanoma cells. Among these four (99m)Tc-labeled peptides, (99m)Tc(EDDA)-HYNIC-AocNle-CycMSHhex displayed the highest melanoma uptake (22.3 ± 1.72 percentage injected dose/g) at 2 h after injection. (99m)Tc(EDDA)-HYNIC-AocNle-CycMSHhex exhibited high tumor-to-normal-organ uptake ratios except for the kidneys. The tumor-to-kidney uptake ratios of (99m)Tc(EDDA)-HYNIC-AocNle-CycMSHhex were 3.29, 3.63, and 6.78 at 2, 4, and 24 h, respectively, after injection. The melanoma lesions were clearly visualized by SPECT/CT using (99m)Tc(EDDA)-HYNIC-AocNle-CycMSHhex as an imaging probe at 2 h after injection. CONCLUSION High melanoma uptake and fast urinary clearance of (99m)Tc(EDDA)-HYNIC-AocNle-CycMSHhex highlighted its potential for metastatic melanoma detection in the future.
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Affiliation(s)
- Haixun Guo
- College of Pharmacy, University of New Mexico, Albuquerque, New Mexico
| | - Yubin Miao
- College of Pharmacy, University of New Mexico, Albuquerque, New Mexico Cancer Research and Treatment Center, University of New Mexico, Albuquerque, New Mexico; and Department of Dermatology, University of New Mexico, Albuquerque, New Mexico
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Rosenkranz AA, Slastnikova TA, Durymanov MO, Sobolev AS. Malignant melanoma and melanocortin 1 receptor. BIOCHEMISTRY. BIOKHIMIIA 2013; 78:1228-37. [PMID: 24460937 PMCID: PMC4064721 DOI: 10.1134/s0006297913110035] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The conventional chemotherapeutic treatment of malignant melanoma still remains poorly efficient in most cases. Thus the use of specific features of these tumors for development of new therapeutic modalities is highly needed. Melanocortin 1 receptor (MC1R) overexpression on the cell surface of the vast majority of human melanomas, making MC1R a valuable marker of these tumors, is one of these features. Naturally, MC1R plays a key role in skin protection against damaging ultraviolet radiation by regulating eumelanin production. MC1R activation is involved in regulation of melanocyte cell division. This article reviews the peculiarities of regulation and expression of MC1R, melanocytes, and melanoma cells, along with the possible connection of MC1R with signaling pathways regulating proliferation of tumor cells. MC1R is a cell surface endocytic receptor, thus considered perspective for diagnostics and targeted drug delivery. A number of new therapeutic approaches that utilize MC1R, including endoradiotherapy with Auger electron and α- and β-particle emitters, photodynamic therapy, and gene therapy are now being developed.
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Affiliation(s)
- A. A. Rosenkranz
- Institute of Gene Biology, Russian Academy of Sciences, ul. Vavilova 34/5, 199334 Moscow, Russia; fax: +7 (499) 135-4105
- Faculty of Biology, Lomonosov Moscow State University, Leninsky Gory 1-12, 119234 Moscow, Russia; fax: +7 (495) 939-4309;
- Targeted Delivery of Pharmaceuticals “Translek” LLC, ul. Vavilova 34/5, 199334 Moscow, Russia;
| | - T. A. Slastnikova
- Institute of Gene Biology, Russian Academy of Sciences, ul. Vavilova 34/5, 199334 Moscow, Russia; fax: +7 (499) 135-4105
| | - M. O. Durymanov
- Institute of Gene Biology, Russian Academy of Sciences, ul. Vavilova 34/5, 199334 Moscow, Russia; fax: +7 (499) 135-4105
- Faculty of Biology, Lomonosov Moscow State University, Leninsky Gory 1-12, 119234 Moscow, Russia; fax: +7 (495) 939-4309;
| | - A. S. Sobolev
- Institute of Gene Biology, Russian Academy of Sciences, ul. Vavilova 34/5, 199334 Moscow, Russia; fax: +7 (499) 135-4105
- Faculty of Biology, Lomonosov Moscow State University, Leninsky Gory 1-12, 119234 Moscow, Russia; fax: +7 (495) 939-4309;
- Targeted Delivery of Pharmaceuticals “Translek” LLC, ul. Vavilova 34/5, 199334 Moscow, Russia;
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10
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Yang J, Liu L, Miao Y. Effects of the Arg-Pro and Gly-Gly-Nle Moieties on Melanocortin-1 Receptor Binding Affinities of α-MSH Peptides. ACS Med Chem Lett 2013; 4. [PMID: 24349641 DOI: 10.1021/ml400309u] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The purpose of this study was to examine the effects of the -Arg-Pro-(RP) and -Gly-Gly-Nle- (GGNle) moieties on the melanoma targeting and clearance properties of 99mTc-peptides. We synthesized four new peptides {Ac-GGNle-CCEHdFRWC-NH2, Ac-GGNle-CCEHdFRWCRP-NH2, Ac-CCEHdFRWC-NleGG-NH2 and Ac-CCEHdFRWCRP-NleGG-NH2} and determined their melanocortin-1 (MC1) receptor binding affinities in B16/F1 melanoma cells. Then we further examined the biodistribution properties of 99mTc-Ac-GGNle-CCEHdFRWCRP-NH2 and 99mTc-Ac-CCEHdFRWCRP-NleGG-NH2 in B16/F1 melanoma-bearing C57 mice. Overall, the Arg-Pro motif was critical for retaining low nanomolar MC1 receptor binding affinity. The deletion of the -RP- moiety dramatically reduced the receptor binding affinities of the peptides. The N-terminus was a better position than C-terminus for the -GGNle- moiety in retaining the lower renal and liver uptake. High melanoma uptake coupled with fast urinary clearance of 99mTc-Ac-GGNle-CCEHdFRWCRP-NH2 provided a new insight into the design of new α-melanocyte stimulating hormone (α-MSH) peptides.
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Affiliation(s)
- Jianquan Yang
- College of Pharmacy, ‡Cancer Research
and Treatment Center, §Department of Dermatology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Liqin Liu
- College of Pharmacy, ‡Cancer Research
and Treatment Center, §Department of Dermatology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Yubin Miao
- College of Pharmacy, ‡Cancer Research
and Treatment Center, §Department of Dermatology, University of New Mexico, Albuquerque, New Mexico 87131, United States
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11
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Gene therapy for advanced melanoma: selective targeting and therapeutic nucleic acids. JOURNAL OF DRUG DELIVERY 2013; 2013:897348. [PMID: 23634303 PMCID: PMC3619548 DOI: 10.1155/2013/897348] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 02/24/2013] [Indexed: 12/21/2022]
Abstract
Despite recent advances, the treatment of malignant melanoma still results in the relapse of the disease, and second line treatment mostly fails due to the occurrence of resistance. A wide range of mutations are known to prevent effective treatment with chemotherapeutic drugs. Hence, approaches with biopharmaceuticals including proteins, like antibodies or cytokines, are applied. As an alternative, regimens with therapeutically active nucleic acids offer the possibility for highly selective cancer treatment whilst avoiding unwanted and toxic side effects. This paper gives a brief introduction into the mechanism of this devastating disease, discusses the shortcoming of current therapy approaches, and pinpoints anchor points which could be harnessed for therapeutic intervention with nucleic acids. We bring the delivery of nucleic acid nanopharmaceutics into perspective as a novel antimelanoma therapeutic approach and discuss the possibilities for melanoma specific targeting. The latest reports on preclinical and already clinical application of nucleic acids in melanoma are discussed.
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Morais M, Oliveira BL, Correia JDG, Oliveira MC, Jiménez MA, Santos I, Raposinho PD. Influence of the Bifunctional Chelator on the Pharmacokinetic Properties of 99mTc(CO)3-Labeled Cyclic α-Melanocyte Stimulating Hormone Analog. J Med Chem 2013; 56:1961-73. [DOI: 10.1021/jm301647t] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Maurício Morais
- Unidade de Ciências Químicas
e Radiofarmacêuticas, IST/ITN, Instituto Superior Técnico,
Universidade Técnica de Lisboa, Estrada Nacional 10, 2686-953,
Sacavém, Portugal
| | - Bruno L. Oliveira
- Unidade de Ciências Químicas
e Radiofarmacêuticas, IST/ITN, Instituto Superior Técnico,
Universidade Técnica de Lisboa, Estrada Nacional 10, 2686-953,
Sacavém, Portugal
| | - João D. G. Correia
- Unidade de Ciências Químicas
e Radiofarmacêuticas, IST/ITN, Instituto Superior Técnico,
Universidade Técnica de Lisboa, Estrada Nacional 10, 2686-953,
Sacavém, Portugal
| | - Maria Cristina Oliveira
- Unidade de Ciências Químicas
e Radiofarmacêuticas, IST/ITN, Instituto Superior Técnico,
Universidade Técnica de Lisboa, Estrada Nacional 10, 2686-953,
Sacavém, Portugal
| | - Maria Angeles Jiménez
- Instituto de Química
Física Rocasolano, Consejo Superior de Investigaciones Científicas
(CSIC), Serrano 119, 28006 Madrid, Spain
| | - Isabel Santos
- Unidade de Ciências Químicas
e Radiofarmacêuticas, IST/ITN, Instituto Superior Técnico,
Universidade Técnica de Lisboa, Estrada Nacional 10, 2686-953,
Sacavém, Portugal
| | - Paula D. Raposinho
- Unidade de Ciências Químicas
e Radiofarmacêuticas, IST/ITN, Instituto Superior Técnico,
Universidade Técnica de Lisboa, Estrada Nacional 10, 2686-953,
Sacavém, Portugal
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13
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Guo H, Gallazzi F, Miao Y. Design and evaluation of new Tc-99m-labeled lactam bridge-cyclized alpha-MSH peptides for melanoma imaging. Mol Pharm 2013; 10:1400-8. [PMID: 23418722 DOI: 10.1021/mp3006984] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The purpose of this study was to examine the melanoma targeting and imaging properties of new (99m)Tc-labeled lactam bridge-cyclized alpha-melanocyte stimulating hormone (α-MSH) peptides using bifunctional chelating agents. MAG3-GGNle-CycMSH(hex), AcCG3-GGNle-CycMSH(hex), and HYNIC-GGNle-CycMSH(hex) peptides were synthesized, and their melanocortin-1 (MC1) receptor binding affinities were determined in B16/F1 melanoma cells. The biodistribution of (99m)Tc-MAG3-GGNle-CycMSH(hex), (99m)Tc-AcCG3-GGNle-CycMSH(hex), (99m)Tc(CO)3-HYNIC-GGNle-CycMSH(hex), and (99m)Tc(EDDA)-HYNIC-GGNle-CycMSH(hex) were determined in B16/F1 melanoma-bearing C57 mice at 2 h postinjection to select a lead peptide for further evaluation. The melanoma targeting and imaging properties of (99m)Tc(EDDA)-HYNIC-GGNle-CycMSH(hex) were further examined because of its high melanoma uptake and fast urinary clearance. The IC50 values of MAG3-GGNle-CycMSH(hex), AcCG3-GGNle-CycMSH(hex), and HYNIC-GGNle-CycMSH(hex) were 1.0 ± 0.05, 1.2 ± 0.19, and 0.6 ± 0.04 nM in B16/F1 melanoma cells, respectively. Among these four (99m)Tc-peptides, (99m)Tc(EDDA)-HYNIC-GGNle-CycMSH(hex) exhibited the highest melanoma uptake (14.14 ± 4.90% ID/g) and fastest urinary clearance (91.26 ± 1.96% ID) at 2 h postinjection. (99m)Tc(EDDA)-HYNIC-GGNle-CycMSH(hex) showed high tumor to normal organ uptake ratios except for the kidneys. The tumor/kidney uptake ratios of (99m)Tc(EDDA)-HYNIC-GGNle-CycMSH(hex) were 2.50 and 3.55 at 4 and 24 h postinjection. The melanoma lesions were clearly visualized by SPECT/CT using (99m)Tc(EDDA)-HYNIC-GGNle-CycMSH(hex) as an imaging probe at 2 h postinjection. Overall, high melanoma uptake coupled with fast urinary clearance of (99m)Tc(EDDA)-HYNIC-GGNle-CycMSH(hex) highlighted its potential for metastatic melanoma detection in the future.
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Affiliation(s)
- Haixun Guo
- College of Pharmacy, University of New Mexico, Albuquerque, New Mexico 87131, USA
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Guo H, Miao Y. Melanoma targeting property of a Lu-177-labeled lactam bridge-cyclized alpha-MSH peptide. Bioorg Med Chem Lett 2013; 23:2319-23. [PMID: 23473679 DOI: 10.1016/j.bmcl.2013.02.069] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2013] [Revised: 02/08/2013] [Accepted: 02/13/2013] [Indexed: 10/27/2022]
Abstract
The purpose of this study was to determine the melanoma targeting property of (177)Lu-DOTA-GGNle-CycMSHhex in B16/F1 melanoma-bearing C57 mice. (177)Lu-DOTA-GGNle-CycMSHhex exhibited high receptor-mediated melanoma uptake and fast urinary clearance. The tumor uptake of (177)Lu-DOTA-GGNle-CycMSHhex was 20.25 ± 4.59 and 21.63 ± 6.27% ID/g at 0.5 and 2h post-injection, respectively. Approximately 83% of injected dose cleared out the body via urinary system at 2h post-injection. (177)Lu-DOTA-GGNle-CycMSHhex showed high tumor to normal organ uptake ratios except for the kidneys. The tumor/kidney uptake ratios of (177)Lu-DOTA-GGNle-CycMSHhex were 2.76 and 1.74 at 2 and 24h post-injection. The melanoma lesions were clearly visualized by SPECT/CT using (177)Lu-DOTA-GGNle-CycMSHhex as an imaging probe at 2h post-injection. Overall, high melanoma uptake coupled with fast urinary clearance of (177)Lu-DOTA-GGNle-CycMSHhex underscored its potential for melanoma treatment in the future.
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Affiliation(s)
- Haixun Guo
- College of Pharmacy, University of New Mexico, Albuquerque, NM 87131, USA
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15
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Huang WY, Davies GL, Davis JJ. High signal contrast gating with biomodified Gd doped mesoporous nanoparticles. Chem Commun (Camb) 2013; 49:60-2. [PMID: 23164954 PMCID: PMC4454276 DOI: 10.1039/c2cc37545a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Internally Gd doped mesoporous nanoparticles have been prepared and exhibit unprecedented relaxivities that are retained on external biomodification. In tuning diffusive water access, image contrast can be reversibly switched in the presence of a specific protein target.
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Affiliation(s)
- Wen-Yen Huang
- Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QZ, UK
| | - Gemma-Louise Davies
- Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QZ, UK
| | - Jason J. Davis
- Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QZ, UK
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16
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Martin ME, O'Dorisio MS, Leverich WM, Kloepping KC, Schultz MK, Schultz MK. "Click"-cyclized (68)Ga-labeled peptides for molecular imaging and therapy: synthesis and preliminary in vitro and in vivo evaluation in a melanoma model system. Recent Results Cancer Res 2013; 194:149-75. [PMID: 22918759 PMCID: PMC3799893 DOI: 10.1007/978-3-642-27994-2_9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Cyclization techniques are used often to impart higher in vivo stability and binding affinity to peptide targeting vectors for molecular imaging and therapy. The two most often used techniques to impart these qualities are lactam bridge construction and disulfide bond formation. While these techniques have been demonstrated to be effective, orthogonal protection/deprotection steps can limit achievable product yields. In the work described in this chapter, new α-melanocyte stimulating hormone (α-MSH) peptide analogs were synthesized and cyclized by copper-catalyzed terminal azide-alkyne cycloaddition "click" chemistry techniques. The α-MSH peptide and its cognate receptor (melanocortin receptor subtype 1, MC1R) represent a well-characterized model system to examine the effect of the triazole linkage for peptide cyclization on receptor binding in vitro and in vivo. Four new DOTA-conjugated α-MSH analogs were cyclized and evaluated by in vitro competitive binding assays, serum stability testing, and in vivo imaging by positron emission tomography (PET) of tumor-bearing mice. These new DOTA-conjugated click-cyclized analogs exhibited selective high binding affinity (<2 nM) for MC1R on melanoma cells in vitro, high stability in human serum, and produced high-contrast PET/CT images of tumor xenografts. (68)Ga-labeled DOTA bioconjugates displayed rapid pharmacokinetics with receptor-mediated tumor accumulation of up to 16 ± 5% ID/g. The results indicate that the triazole ring is an effective bioisosteric replacement for the standard lactam bridge assemblage for peptide cyclization. Radiolabeling results confirm that Cu catalyst is sufficiently removed prior to DOTA chelator addition to enable insertion of radio metals or stable metals for molecular imaging and therapy. Thus, these click-chemistry-cyclized variants show promise as agents for melanocortin receptor-targeted imaging and radionuclide therapy.
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Affiliation(s)
- Molly E. Martin
- Department of Pediatric Hematology/Oncology, Carver College of Medicine, The University of Iowa
| | - M. Sue O'Dorisio
- Department of Pediatric Hematology/Oncology, Carver College of Medicine, The University of Iowa,Corresponding Author: Michael K. Schultz PhD, Departments of Radiology and Radiation Oncology (Free Radical Radiation Biology Program), Carver College of Medicine, The University of Iowa, ML B180, 500 Newton Road, Iowa City, IA 52242. Tel: +1 (319) 356-3380; Fax: +1 (319) 335-8668;
| | - Whitney M. Leverich
- Department of Pediatric Hematology/Oncology, Carver College of Medicine, The University of Iowa
| | - Kyle C. Kloepping
- Department of Radiology, Carver College of Medicine, The University of Iowa,Department of Radiation Oncology (Free Radical Radiation Biology Program), Carver College of Medicine, The University of Iowa
| | - Michael K. Schultz
- Department of Radiology, Carver College of Medicine, The University of Iowa,Department of Radiation Oncology (Free Radical Radiation Biology Program), Carver College of Medicine, The University of Iowa,Corresponding Author: Michael K. Schultz PhD, Departments of Radiology and Radiation Oncology (Free Radical Radiation Biology Program), Carver College of Medicine, The University of Iowa, ML B180, 500 Newton Road, Iowa City, IA 52242. Tel: +1 (319) 356-3380; Fax: +1 (319) 335-8668;
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MSH radiopeptides for targeting melanoma metastases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 681:133-42. [PMID: 21222266 DOI: 10.1007/978-1-4419-6354-3_11] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Radiolabeled peptides have become important tools for preclinical cancer research and in nuclear oncology they serve as diagnostic and more recently also as therapeutic agents. Whereas the development of receptor-mediated targeting for therapy has been confined to some radiolabeled antibodies and somatostatin/SRIF analogs, recent research into radiolabeled α-Melanocyte-stimulating hormone (α-MSH) and its receptor MC1R (over-)expressed by melanoma tumor cells has demonstrated that small metastatic melanoma lesions in experimental animals are specifically targeted by MSH radiopeptides. Thus MSH radiopharmaceuticals will eventually open a new avenue for the treatment of melanoma metastases in man, provided that the targeting efficiency can be further enhanced and nonspecific incorporation into nontarget organs, e.g., the kidneys, minimized. Some novel MSH lead compounds containing a glyco moiety, added negatively charged groups or a cyclic structure show very promising in vivo targeting characteristics.
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Guo H, Miao Y. Cu-64-labeled lactam bridge-cyclized α-MSH peptides for PET imaging of melanoma. Mol Pharm 2012; 9:2322-30. [PMID: 22780870 DOI: 10.1021/mp300246j] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The purpose of this study was to examine and compare the melanoma targeting and imaging properties of (64)Cu-NOTA-GGNle-CycMSH(hex) {(64)Cu-1,4,7-triazacyclononane-1,4,7-triacetic acid-Gly-Gly-Nle-c[Asp-His-DPhe-Arg-Trp-Lys]-CONH2} and (64)Cu-DOTA-GGNle-CycMSH(hex) {(64)Cu-1,4,7,10-tetraazacyclononane-1,4,7,10-tetraacetic acid-GGNle-CycMSH(hex)}. Two lactam bridge-cyclized peptides, NOTA-GGNle-CycMSH(hex) and DOTA-GGNle-CycMSH(hex), were synthesized using fluorenylmethyloxy carbonyl (Fmoc) chemistry. The melanocortin-1 (MC1) receptor binding affinity of NOTA-GGNle-CycMSH(hex) was determined in B16/F1 melanoma cells and compared with DOTA-GGNle-CycMSH(hex). The melanoma targeting and imaging properties of (64)Cu-NOTA-GGNle-CycMSH(hex) and (64)Cu-DOTA-GGNle-CycMSH(hex) were determined in B16/F1 melanoma-bearing C57 mice. NOTA-GGNle-CycMSH(hex) and DOTA-GGNle-CycMSH(hex) displayed comparable MC1 receptor binding affinities (1.6 vs 2.1 nM). The substitution of DOTA with NOTA dramatically increased the melanoma uptake and decreased the renal and liver uptake of (64)Cu-NOTA-GGNle-CycMSH(hex). The tumor uptake of (64)Cu-NOTA-GGNle-CycMSH(hex) was between 12.39 ± 1.61 and 12.71 ± 2.68% ID/g at 0.5, 2, and 4 h postinjection. The accumulation of (64)Cu-NOTA-GGNle-CycMSH(hex) activity in normal organs was lower than 1.02% ID/g except for the kidneys 2, 4, and 24 h postinjection. The tumor/liver uptake ratios of (64)Cu-NOTA-GGNle-CycMSHhex were 17.96, 16.95, and 8.02, whereas the tumor/kidney uptake ratios of (64)Cu-NOTA-GGNle-CycMSH(hex) were 2.52, 3.60, and 5.74 at 2, 4, and 24 h postinjection, respectively. Greater than 91% of the injected radioactivity cleared through the urinary system by 2 h postinjection. The substitution of DOTA with NOTA resulted in a dramatic increase in melanoma uptake and decrease in renal and liver uptake of (64)Cu-NOTA-GGNle-CycMSH(hex) as compared to (64)Cu-DOTA-GGNle-CycMSH(hex). High melanoma uptake coupled with low accumulation in nontarget organs suggested (64)Cu-NOTA-GGNle-CycMSH(hex) as a lead radiolabeled peptide for melanoma imaging and therapy.
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Affiliation(s)
- Haixun Guo
- College of Pharmacy, ‡Cancer Research and Treatment Center, and §Department of Dermatology, University of New Mexico , Albuquerque, New Mexico 87131, United States
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Guo H, Gallazzi F, Miao Y. Gallium-67-labeled lactam bridge-cyclized alpha-MSH peptides with enhanced melanoma uptake and reduced renal uptake. Bioconjug Chem 2012; 23:1341-8. [PMID: 22621181 DOI: 10.1021/bc300191z] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The purpose of this study was to examine the melanoma targeting and pharmacokinetic properties of (67)Ga-DOTA-GGNle-CycMSHhex {(67)Ga-1,4,7,10-tetraazacyclononane-1,4,7,10-tetraacetic acid-Gly-Gly-Nle-c[Asp-His-DPhe-Arg-Trp-Lys]-CONH2} and (67)Ga-NOTA-GGNle-CycMSHhex {(67)Ga-1,4,7-triazacyclononane-1,4,7-triacetic acid-Gly-Gly-Nle-c[Asp-His-DPhe-Arg-Trp-Lys]-CONH2} and compare with (67)Ga-DOTA-GlyGlu-CycMSH {(67)Ga-DOTA-Gly-Glu-c[Lys-Nle-Glu-His-DPhe-Arg-Trp-Gly-Arg-Pro-Val-Asp]} we previously reported. DOTA-GGNle-CycMSHhex and NOTA-GGNle-CycMSHhex were synthesized using fluorenylmethyloxy carbonyl (Fmoc) chemistry. The melanocortin-1 (MC1) receptor binding affinity of NOTA-GGNle-CycMSHhex was determined in B16/F1 melanoma cells and compared with DOTA-GGNle-CycMSHhex. The melanoma targeting and pharmacokinetic properties of (67)Ga-NOTA-GGNle-CycMSHhex and (67)Ga-DOTA-GGNle-CycMSHhex were determined in B16/F1 melanoma-bearing C57 mice. NOTA-GGNle-CycMSHhex and DOTA-GGNle-CycMSHhex displayed comparable MC1 receptor binding affinities (1.6 vs 2.1 nM) in B16/F1 melanoma cells. Both (67)Ga-NOTA-GGNle-CycMSHhex and (67)Ga-DOTA-GGNle-CycMSHhex exhibited dramatically enhanced melanoma uptake and reduced renal uptake than (67)Ga-DOTA-GlyGlu-CycMSH in B16/F1 melanoma-bearing C57 mice. Furthermore, (67)Ga-NOTA-GGNle-CycMSHhex exhibited more favorable radiolabeling conditions (>85% radiolabeling yields started at 37 °C), as well as higher tumor/kidney uptake ratios than (67)Ga-DOTA-GGNle-CycMSHhex at 0.5, 2, and 24 h postinjection. High melanoma uptake coupled with low renal uptake highlighted the potential of (67)Ga-NOTA-GGNle-CycMSHhex for melanoma imaging and therapy.
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Affiliation(s)
- Haixun Guo
- College of Pharmacy, ‡Cancer Research and Treatment Center, §Department of Dermatology, University of New Mexico , Albuquerque, New Mexico 87131, United States
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Yang J, Lu J, Miao Y. Structural modification on the Lys linker enhanced tumor to kidney uptake ratios of 99mTc-labeled RGD-conjugated α-MSH hybrid peptides. Mol Pharm 2012; 9:1418-24. [PMID: 22452443 DOI: 10.1021/mp2006642] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The purpose of this study was to examine whether the structural modification on the positively charged Lys linker could reduce the kidney uptake of (99m)Tc-labeled Arg-Gly-Asp (RGD)-conjugated α-melanocyte stimulating hormone (α-MSH) hybrid peptides. The RGD motif {cyclic(Arg-Gly-Asp-D-Tyr-Asp)} was coupled to [Cys(3,4,10), D-Phe(7), Arg(11)]α-MSH(3-13) {(Arg(11))CCMSH} through a neutral glycine linker to eliminate the positively charged amino side chain of the Lys linker or without a linker to delete the Lys linker. The receptor binding affinity of RGD-Gly-(Arg(11))CCMSH and RGD-(Arg(11))CCMSH was determined in B16/F1 melanoma cells. The melanoma targeting and imaging properties of (99m)Tc-RGD-Gly-(Arg(11))CCMSH and (99m)Tc-RGD-(Arg(11))CCMSH were determined in B16/F1 melanoma-bearing C57 mice. The structural modification on the Lys linker retained a low nanomolar receptor binding affinity of RGD-Gly-(Arg(11))CCMSH and RGD-(Arg(11))CCMSH (1.5 and 1.0 nM, respectively). The structural modification on the Lys linker dramatically decreased the renal uptake of (99m)Tc-RGD-Gly-(Arg(11))CCMSH and (99m)Tc-RGD-(Arg(11))CCMSH by 79% and 77% at 4 h postinjection compared to (99m)Tc-RGD-Lys-(Arg(11))CCMSH. (99m)Tc-RGD-(Arg(11))CCMSH displayed a higher melanoma uptake (16.12 ± 3.09% ID/g) than (99m)Tc-RGD-Gly-(Arg(11))CCMSH (11.50 ± 1.01% ID/g) at 2 postinjection. The tumor uptake of (99m)Tc-RGD-(Arg(11))CCMSH was 1.4 times the tumor uptake of (99m)Tc-RGD-Gly-(Arg(11))CCMSH at 2 postinjection. A dramatically enhanced tumor-to-kidney uptake ratio of (99m)Tc-RGD-(Arg(11))CCMSH suggests that (188)Re-RGD-(Arg(11))CCMSH may behave in a similar fashion warranting future evaluation for melanoma treatment.
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Affiliation(s)
- Jianquan Yang
- College of Pharmacy, University of New Mexico, Albuquerque, New Mexico 87131, United States
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Guo H, Gallazzi F, Sklar LA, Miao Y. A novel indium-111-labeled gonadotropin-releasing hormone peptide for human prostate cancer imaging. Bioorg Med Chem Lett 2011; 21:5184-7. [PMID: 21821417 DOI: 10.1016/j.bmcl.2011.07.055] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 07/12/2011] [Accepted: 07/13/2011] [Indexed: 11/25/2022]
Abstract
The purpose of this study was to evaluate the tumor targeting and imaging properties of a novel (111)In-labeled gonadotropin-releasing hormone (GnRH) peptide {1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-Ahx-(D-Lys(6)-GnRH1)} for human prostate cancer. The biodistribution and tumor imaging properties of (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) were determined in DU145 human prostate cancer-xenografted nude mice. (111)In-DOTA-Ahx-(d-Lys(6)-GnRH1) exhibited rapid tumor uptake (1.27 ± 0.40% ID/g at 0.5h post-injection) coupled with fast whole-body clearance through the urinary system. The DU145 human prostate cancer-xenografted tumor lesions were clearly visualized by single photon emission computed tomography (SPECT)/CT at 0.5h post-injection of (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1). The successful imaging of DU145 human prostate cancer-xenografted tumor lesions using (111)In-DOTA-Ahx-(d-Lys(6)-GnRH1) highlighted its potential as a novel imaging probe for human prostate cancer imaging.
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Affiliation(s)
- Haixun Guo
- College of Pharmacy, University of New Mexico, Albuquerque, NM 87131, USA
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Guo H, Lu J, Hathaway H, Royce ME, Prossnitz ER, Miao Y. Synthesis and evaluation of novel gonadotropin-releasing hormone receptor-targeting peptides. Bioconjug Chem 2011; 22:1682-9. [PMID: 21749045 DOI: 10.1021/bc200252j] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The purpose of this study was to develop novel radiolabeled gonadotropin-releasing hormone (GnRH) receptor-targeting peptides for breast cancer imaging. Three novel 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-conjugated GnRH peptides were designed and synthesized. The radiometal chelator DOTA was conjugated to the epsilon or alpha amino group of D-lysine, or the epsilon amino group of L-lysine via an Ahx {aminohexanoic acid} linker to generate DOTA-Ahx-(D-Lys(6)-GnRH1), DOTA-Ahx-(D-Lys(6)-GnRH2) and DOTA-Ahx-(L-Lys(6)-GnRH3), respectively. The conjugation of the DOTA to the epsilon amino group of D-lysine (rather than alpha amino group of D-lysine nor epsilon amino group of L-lysine) maintained the nanomolar GnRH receptor binding affinity. The IC(50) values of DOTA-Ahx-(D-Lys(6)-GnRH1), DOTA-Ahx-(D-Lys(6)-GnRH2) and DOTA-Ahx-(L-Lys(6)-GnRH3) were 36.1 nM, 10.6 mM and 4.3 mM, respectively. Since only DOTA-Ahx-(D-Lys(6)-GnRH1) displayed nanomolar receptor binding affinity, the specific GnRH receptor binding of (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) was determined in human GnRH receptor membrane preparations. Furthermore, the biodistribution and tumor imaging properties of (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) were examined in MDA-MB-231 human breast cancer-xenografted nude mice. (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) exhibited specific GnRH receptor binding and rapid tumor uptake (1.76 ± 0.58% ID/g at 0.5 h postinjection) coupled with fast whole-body clearance through the urinary system. The MDA-MB-231 human breast cancer-xenografted tumor lesions were clearly visualized by single photon emission computed tomography (SPECT)/CT at 1 h postinjection of (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1). The profound impact of DOTA position on the binding affinity of the GnRH peptide provided a new insight into the design of novel radiolabeled GnRH peptides. The successful imaging of MDA-MB-231 human breast cancer-xenografted tumor lesions using (111)In-DOTA-Ahx-(D-Lys(6)-GnRH1) suggested its potential as a novel imaging probe for human breast cancer imaging.
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Affiliation(s)
- Haixun Guo
- College of Pharmacy, University of New Mexico, Albuquerque, New Mexico 87131, United States
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Abstract
A number of medical imaging techniques are used heavily in the provision of spatially resolved information on disease and physiological status and accordingly play a critical role in clinical diagnostics and subsequent treatment. Though, for most imaging modes, contrast is potentially enhanced through the use of contrast agents or improved hardware or imaging protocols, no single methodology provides, in isolation, a detailed mapping of anatomy, disease markers or physiological status. In recent years, the concept of complementing the strengths of one imaging modality with those of another has come to the fore and been further bolstered by the development of fused instruments such as PET/CT and PET/MRI stations. Coupled with the continual development in imaging hardware has been a surge in reports of contrast agents bearing multiple functionality, potentially providing not only a powerful and highly sensitised means of co-localising physiological/disease status and anatomy, but also the tracking and delineation of multiple markers and indeed subsequent or simultaneous highly localized therapy ("theragnostics").
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Affiliation(s)
- Wen-Yen Huang
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford, OX1 3QR, UK
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Bhattacharyya S, Dixit M. Metallic radionuclides in the development of diagnostic and therapeutic radiopharmaceuticals. Dalton Trans 2011; 40:6112-28. [PMID: 21541393 PMCID: PMC3716284 DOI: 10.1039/c1dt10379b] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Metallic radionuclides are the mainstay of both diagnostic and therapeutic radiopharmaceuticals. Therapeutic nuclear medicine is less advanced but has tremendous potential if the radionuclide is accurately targeted. Great interest exists in the field of inorganic chemistry for developing target specific radiopharmaceuticals based on radiometals for non-invasive disease detection and cancer radiotherapy. This perspective will focus on the nuclear properties of a few important radiometals and their recent applications to developing radiopharmaceuticals for imaging and therapy. Other topics for discussion will include imaging techniques, radiotherapy, analytical techniques, and radiation safety. The ultimate goal of this perspective is to introduce inorganic chemists to the field of nuclear medicine and radiopharmaceutical development, where many applications of fundamental inorganic chemistry can be found.
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Affiliation(s)
- Sibaprasad Bhattacharyya
- Applied and Developmental Research Directorate, SAIC-Frederick, National Cancer Institute (NIH/NCI) at Frederick, 1050 Boyles Street, Bldg. 376, Frederick, Maryland, USA.
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Guo H, Yang J, Gallazzi F, Miao Y. Effects of the amino acid linkers on the melanoma-targeting and pharmacokinetic properties of 111In-labeled lactam bridge-cyclized alpha-MSH peptides. J Nucl Med 2011; 52:608-16. [PMID: 21421725 DOI: 10.2967/jnumed.110.086009] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED The purpose of this study was to examine the profound effects of the amino acid linkers on the melanoma-targeting and pharmacokinetic properties of (111)In-labeled lactam bridge-cyclized DOTA-[X]-CycMSH(hex) {1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-[X]-c[Asp-His-dPhe-Arg-Trp-Lys]-CONH(2); X = GGNle, GENle, or NleGE; GG = -Gly-Gly- and GE = -Gly-Glu-} peptides. METHODS Three novel peptides (DOTA-GGNle-CycMSH(hex), DOTA-GENle-CycMSH(hex), and DOTA-NleGE-CycMSH(hex)) were designed and synthesized. The melanocortin-1 (MC1) receptor-binding affinities of the peptides were determined in B16/F1 melanoma cells. The melanoma-targeting and pharmacokinetic properties of (111)In-DOTA-GGNle-CycMSH(hex) and (111)In-DOTA-GENle-CycMSH(hex) were determined in B16/F1 melanoma-bearing C57 mice. RESULTS DOTA-GGNle-CycMSH(hex) and DOTA-GENle-CycMSH(hex) displayed 2.1 and 11.5 nM MC1 receptor-binding affinities, whereas DOTA-NleGE-CycMSH(hex) showed 873.4 nM MC1 receptor-binding affinity. The introduction of the -GG- linker maintained high melanoma uptake while decreasing kidney and liver uptake of (111)In-DOTA-GGNle-CycMSH(hex). The tumor uptake of (111)In-DOTA-GGNle-CycMSH(hex) was 19.05 ± 5.04 and 18.6 ± 3.56 percentage injected dose per gram at 2 and 4 h after injection, respectively. (111)In-DOTA-GGNle-CycMSH(hex) exhibited 28%, 32%, and 42% less kidney uptake than (111)In-DOTA-Nle-CycMSH(hex) we reported previously, and 61%, 65%, and 68% less liver uptake than (111)In-DOTA-Nle-CycMSH(hex) at 2, 4, and 24 h after injection, respectively. CONCLUSION The amino acid linkers exhibited profound effects on the melanoma-targeting and pharmacokinetic properties of the (111)In-labeled lactam bridge-cyclized α-melanocyte-stimulating hormone peptides. Introduction of the -GG- linker maintained high melanoma uptake while reducing kidney and liver uptake of (111)In-DOTA-GGNle-CycMSH(hex), highlighting its potential as an effective imaging probe for melanoma detection, as well as a therapeutic peptide for melanoma treatment when labeled with a therapeutic radionuclide.
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Affiliation(s)
- Haixun Guo
- College of Pharmacy, University of New Mexico, Albuquerque, New Mexico 87131, USA
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Raposinho PD, Correia JDG, Oliveira MC, Santos I. Melanocortin-1 receptor-targeting with radiolabeled cyclic α-melanocyte-stimulating hormone analogs for melanoma imaging. Biopolymers 2011; 94:820-9. [PMID: 20564045 DOI: 10.1002/bip.21490] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Melanoma is a type of skin cancer known for its high aggressiveness, early dissemination of metastases, and poor prognosis once metastasized. Thus, early diagnosis of melanoma is a key issue for increasing patient survival. The overexpression of melanocortin-1 receptors (MC1R) in isolated melanoma cells and melanoma tissues led to the radiolabeling of several linear and cyclic MC analogs for melanoma imaging or therapy. Cyclization of α-melanocyte stimulating hormone (α-MSH) peptides has been successfully used to improve binding affinity and in vivo stability of peptides. Herein, we describe the different peptide cyclization strategies recently reported for radiolabeled α-MSH analogs and discuss how such strategies affect MC1R binding affinity, pharmacokinetic profile, and MC1R-melanoma imaging. This review also highlights how the nature of the radiometal and labeling approach influence those properties. Among the cyclized α-MSH peptides reported, (99m)Tc/(111)In-labeled metal-cyclized and lactam bridge-cyclized peptides displayed the highest melanoma and lowest renal uptake values in B16/F1 melanoma-bearing mice and became the most promising tools to be further explored as potential melanoma imaging probes.
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Affiliation(s)
- Paula D Raposinho
- Unidade de Ciências Químicas e Radiofarmacêuticas, ITN, Estrada Nacional 10, 2686-953 Sacavém, Portugal.
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Correia JDG, Paulo A, Raposinho PD, Santos I. Radiometallated peptides for molecular imaging and targeted therapy. Dalton Trans 2011; 40:6144-67. [DOI: 10.1039/c0dt01599g] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Martinelli J, Balali-Mood B, Panizzo R, Lythgoe MF, White AJP, Ferretti P, Steinke JHG, Vilar R. Coordination chemistry of amide-functionalised tetraazamacrocycles: structural, relaxometric and cytotoxicity studies. Dalton Trans 2010; 39:10056-67. [PMID: 20877892 DOI: 10.1039/c0dt00815j] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Three different tetraazamacrocyclic ligands containing four amide substituents that feature groups (namely allyl, styryl and propargyl groups) suitable for polymerisation have been synthesised. Gadolinium(III) complexes of these three ligands have been prepared as potential monomers for the synthesis of polymeric MRI contrast agents. To assess the potential of these monomers as MRI contrast agents, their relaxation enhancement properties and cytotoxicity have been determined. A europium(III) complex of one of these ligands (with propargyl substituents) is also presented together with its PARACEST properties. In addition, to gain further insight into the coordination chemistry of the tetra-propargyl substituted ligand, the corresponding zinc(II) and cadmium(II) complexes have been prepared. The X-ray crystal structures of the tetra-propargyl ligand and its corresponding gadolinium(III), zinc(II) and cadmium(II) complexes are also presented.
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Lee S, Xie J, Chen X. Peptides and peptide hormones for molecular imaging and disease diagnosis. Chem Rev 2010; 110:3087-111. [PMID: 20225899 DOI: 10.1021/cr900361p] [Citation(s) in RCA: 253] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Seulki Lee
- Laboratory of Molecular Imaging and Nanomedicine, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, 31 Center Drive, Suite 1C14, Bethesda, Maryland 20892-2281, USA
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