Abstract
To endow the polymeric prodrug with smart properties through a safe and simple method, matrix metalloproteinase (MMPs) responsive peptide GPLGVRGDG was introduced into the block copolymer to prepare TPGS(3350)-GPLGVRGDG-DOX&DOX micelles, where TPGS(3350) is D-α-tocopheryl polyethylene glycol 3350 succinate. During the doxorubicin delivery, the cleavage of the peptide chain triggers de-PEGylation, and the remaining VRGDG sequence was retained on the surface of the micelles, which can act as a ligand to facilitate cell uptake. Moreover, the cytotoxicity of TPGS(3350)-GPLGVRGDG-DOX&DOX micelles against 4T1 cells was significantly improved, compared with TPGS(3350)-GPLGVRG-DOX&DOX micelles and TPGS(3350)-DOX&DOX micelles. During in vivo studies, TPGS(3350)-GPLGVRGDG-DOX&DOX micelles exhibited good anticancer efficacy with long circulation in the body and more efficient accumulation at the tumor site. Therefore, TPGS(3350)-GPLGVRGDG-DOX&DOX micelles have improved antitumor activity and reduced toxic side effects. This work opens new potential for exploring the strategy of drug delivery in clinical applications.