TY - JOUR AB - RGD-cryptophycin and isoDGR-cryptophycin conjugates were synthetized by combining peptidomimetic integrin ligands and cryptophycin, a highly potent tubulin-binding antimitotic agent across lysosomally cleavable Val-Ala or uncleavable linkers. The conjugates were able to effectively inhibit binding of biotinylated vitronectin to integrin alphavbeta3, showing a binding affinity in the same range as that of the free ligands. The antiproliferative activity of the novel conjugates was evaluated on human melanoma cells M21 and M21-L with different expression levels of integrin alphavbeta3, showing nanomolar potency of all four compounds against both cell lines. Conjugates containing uncleavable linker show reduced activity compared to the corresponding cleavable conjugates, indicating efficient intracellular drug release in the case of cryptophycin-based SMDCs. However, no significant correlation between the in vitro biological activity of the conjugates and the integrin alphavbeta3 expression level was observed, which is presumably due to a non-integrin-mediated uptake. This reveals the complexity of effective and selective alphavbeta3 integrin-mediated drug delivery. DA - 2019 DO - 10.1002/open.201900110 LA - eng IS - 6 M2 - 737 PY - 2019 SN - 2191-1363 SP - 737-742 T2 - ChemistryOpen TI - Conjugates of Cryptophycin and RGD or isoDGR Peptidomimetics for Targeted Drug Delivery UR - https://nbn-resolving.org/urn:nbn:de:0070-pub-29364950 Y2 - 2024-11-22T03:30:31 ER -