The goal of the proposed work is to develop heterobivalent agents for targeted delivery of imaging and therapy to metastatic melanoma. These agents contain two ligands that direct the construct to crosslink two different cell surface receptors, resulting in dramatic increases in binding selectivity. This has advantages over agents directed against single receptors in that they do not rely on overexpression of a single cell surface protein. The proposed constructs also have advantages over other multifunctional agents in that they are produced via convergent synthesis and are designed to be relatively small with favorable ADME characteristics. Work during the first period of support has (1) identified and validated a receptor combination that can be used to target a subset of metastatic melanomas, and (2) demonstrated a proof-of-principle that synthetic heterobivalent agents can crosslink heterologous receptors. These constructs bound with up to 50-fold higher affinity compared to corresponding monovalent interactions. Current research will combine these two advances to develop heterobivalent agents against an identified target receptor pair. To achieve this goal, Aim 1 will use a previously developed G-protein coupled receptor (GPCR) system to derive analytical solutions that predict behavior of multivalent ligands as imaging agents.
Aim 2 will develop bivalent agents that target a receptor combination identified in the first period of support: N-formyl peptide receptor like, type 2 (FPRL2) and the type 1 melanocortin receptor (MC1R). In this aim, optimum linker and ligand chemistries will be determined with high-throughput binding assays. Bivalent ligands will be labeled with fluorophores for testing by in-cyto and in-vivo imaging. Those with optimum characteristics will be labeled with DOTA. DOTA derivatives will be used to chelate Eu for ex vivo fluorescence and 111In for in vivo SPECT assessment of pharmacokinetics and biodistribution.
Aim 3 will continue the validation effort for 21 additional receptors that were identified as targets during the first period of support. These will be validated primarily though immunohistochemistry of tissue microarrays containing multiple melanoma grades as well as multiple normal tissues. It is expected that this work will result in the validation of additional receptor combinations that will target a majority of metastatic melanomas. At the end of this next period of support, we will have (1) developed more precise analytical methods to predict the behavior of multivalent ligands as imaging agents;(2) developed targeting ligands that will be useful against 40-50% of metastatic melanomas and (3) identified additional 3- and 4-receptor target combinations for the remaining molecular phenotypes of this disease.The goal of the proposed work is to develop platform targeting agents for delivery of imaging and therapy to metastatic melanoma. These agents are heterobivalent in that they link together two ligands that are directed against two different cell surface receptors. Such agents have advantages over agents directed against single epitopes by not relying on a single overexpressed cell surface protein. They also have advantages over other multifunctional agents in that they are produced via convergent synthesis and hence are relatively small with acceptable ADME characteristics.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA097360-09
Application #
8288314
Study Section
Special Emphasis Panel (ZRG1-MEDI-A (09))
Program Officer
Menkens, Anne E
Project Start
2002-07-01
Project End
2014-05-31
Budget Start
2012-06-01
Budget End
2014-05-31
Support Year
9
Fiscal Year
2012
Total Cost
$600,715
Indirect Cost
$112,179
Name
H. Lee Moffitt Cancer Center & Research Institute
Department
Type
DUNS #
139301956
City
Tampa
State
FL
Country
United States
Zip Code
33612
Elshan, N G R Dayan; Patek, Renata; Vagner, Josef et al. (2014) Spectrophotometric determination and removal of unchelated europium ions from solutions containing Eu-diethylenetriaminepentaacetic acid chelate-peptide conjugates. Anal Biochem 464:24-9
Fernandes, Steve M; Lee, Yeon Sun; Gillies, Robert J et al. (2014) Synthesis and evaluation of bivalent ligands for binding to the human melanocortin-4 receptor. Bioorg Med Chem 22:6360-5
Brabez, Nabila; Nguyen, Kevin L; Saunders, Kara et al. (2013) Synthesis and evaluation of cholecystokinin trimers: a multivalent approach to pancreatic cancer detection and treatment. Bioorg Med Chem Lett 23:2422-5
Martinez, Gary V; Navath, Suryakiran; Sewda, Kamini et al. (2013) Demonstration of a sucrose-derived contrast agent for magnetic resonance imaging of the GI tract. Bioorg Med Chem Lett 23:2061-4
Barkey, Natalie M; Preihs, Christian; Cornnell, Heather H et al. (2013) Development and in vivo quantitative magnetic resonance imaging of polymer micelles targeted to the melanocortin 1 receptor. J Med Chem 56:6330-8
Alleti, Ramesh; Vagner, Josef; Dehigaspitiya, Dilani Chathurika et al. (2013) Synthesis and characterization of time-resolved fluorescence probes for evaluation of competitive binding to melanocortin receptors. Bioorg Med Chem 21:5029-38
Tafreshi, Narges K; Silva, Ariosto; Estrella, Veronica C et al. (2013) In vivo and in silico pharmacokinetics and biodistribution of a melanocortin receptor 1 targeted agent in preclinical models of melanoma. Mol Pharm 10:3175-85
Rao, Venkataramanarao; Alleti, Ramesh; Xu, Liping et al. (2011) A sucrose-derived scaffold for multimerization of bioactive peptides. Bioorg Med Chem 19:6474-82
Barkey, Natalie M; Tafreshi, Narges K; Josan, Jatinder S et al. (2011) Development of melanoma-targeted polymer micelles by conjugation of a melanocortin 1 receptor (MC1R) specific ligand. J Med Chem 54:8078-84
Josan, Jatinder S; Handl, Heather L; Sankaranarayanan, Rajesh et al. (2011) Cell-specific targeting by heterobivalent ligands. Bioconjug Chem 22:1270-8

Showing the most recent 10 out of 28 publications