Comparison of biological properties of 111In-labeled dimeric cyclic RGD peptides

The results from this study suggest that replacing PEG4 linkers between two RGD moieties with a pair of SAA, PEG2 and 1,2,3-triazole groups has little impact on integrin αvβ3 binding affinity and tumor uptake of 111In-labeled dimeric cyclic RGD peptides. Despite the subtle differences in their excretion kinetics from noncancerous tissues, 111In(DOTA-Galacto-RGD2) and 111In(DOTA-3P-RGD2) are useful radiotracers for imaging integrin αvβ3-positive breast tumors.