Development of a time-resolved fluorescence probe for evaluation of competitive binding to the cholecystokinin 2 receptor.

The synthesis, characterization, and use of Eu-DTPA-PEGO-Trp-Nle-Asp-Phe-NH2 (Eu-DTPA-PEGO-CCK4), a luminescent probe targeted to cholecystokinin 2 receptor (CCK2R, aka CCKBR), are described. The probe was prepared by solid phase synthesis. A Kd value of 17±2nM was determined by means of saturation binding assays using HEK-293 cells that overexpress CCK2R.

Trigonal scaffolds for multivalent targeting of melanocortin receptors.

Melanocortin receptors can be used as biomarkers to detect and possibly treat melanoma. To these ends, molecules bearing one, two, or three copies of the weakly binding ligand MSH(4) were attached to scaffolds based on phloroglucinol, tripropargylamine, and 1,4,7-triazacyclononane by means of the copper-assisted azide-alkyne cyclization. This synthetic design allows rapid assembly of multivalent molecules.

Multivalent Interactions: Synthesis and Evaluation of Melanotropin Multimers - Tools for Melanoma Targeting.

In order to develop agents for early detection and selective treatment of melanomas, high affinity and high specificity molecular tools are required. Enhanced specificity may be obtained by simultaneously binding to multiple cell surface targets the use of multimeric analogs of naturally occurring ligands. Trimers targeting overexpressed melanocortin receptors have been found to be potential candidates for this purpose.