Enhanced cytotoxicity of a polymer―drug conjugate with triple payload of paclitaxel

The development of targeting approaches to selectively release chemotherapeutic drugs into malignant tissue is a major challenge in anticancer therapy. We have synthesized an N-(2-hydroxypropyl)-methacrylamide (HPMA) copolymer-drug conjugate with an AB(3) self-immolative dendritic linker. HPMA copolymers are known to accumulate selectively in tumors. The water-soluble polymer-drug conjugate was designed to release a triple payload of the hydrophobic drug paclitaxel as a result of cleavage by the endogenous enzyme cathepsin B. The polymer-drug conjugate exhibited enhanced cytotoxicity on murine prostate adenocarcinoma (TRAMP C2) cells in comparison to a classic monomeric drug-polymer conjugate.