Cyclo(RGDyK) (trifluoroacetate salt) (Synonyms: c(RGDyK), cyclic-L-Arg-L-Gly-L-Asp-D-Tyr-L-Lys)

Cyclo(RGDyK) is a cyclic peptide ligand of αVβ3 integrin (IC₅₀ = 37.5 nM) that contains the αVβ3 integrin-binding sequence arginine-glycine-aspartate (RGD).¹ It has been conjugated to radiolabels or fluorescent probes for the visualization of αVβ3-mediated neoangiogenesis or optical imaging of αVβ3-expressing tumors in live mice.^2,1 Cyclo(RGDyK) has also been conjugated to the DNA topoisomerase I inhibitor SN38 and an SN38-releasing trigger moiety to form a prodrug that targets cells overexpressing αVβ3 integrin and induces cytotoxicity in KB human cervical carcinoma cells.³

1.Chen, X., Conti, P.S., and Moats, R.A.In vivo near-infrared fluorescence imaging of integrin αvβ3 in brain tumor xenograftsCancer Res.64(21)8009-8014(2004) 2.van Hagen, P.M., Breeman, W.A., Bernard, H.F., et al.Evaluation of a radiolabelled cyclic DTPA-RGD analogue for tumour imaging and radionuclide therapyInt. J. Cancer90(4)186-198(2000) 3.Huang, B., Desai, A., Tang, S., et al.The synthesis of a c(RGDyK) targeted SN38 prodrug with an indolequinone structure for bioreductive drug releaseOrg. Lett.12(7)1384-1387(2010)