Enhancing curcumin anticancer efficacy through poly(anhydride ester)-b-poly(ethylene glycol) block copolymer micelle encapsulation

We report herein the development of a novel aqueous formulation and improved antitumor activity for curcumin by encapsulating it into a biocompatible and biodegradable poly (L-lactic acid) based poly(anhydride-ester)-b-poly(ethylene glycol) (PAE-b-PEG) block copolymer micelle. The resulting curcumin loaded micelles (Cur-micelles) were completely water-dispersible, overcoming the problem of poor water solubility that has limited its efficacy and bioavailability. In vitro cellular studies revealed that the Cur-micelles were taken up mainly via endocytosis route and exhibited higher cytotoxicities toward model cancer cell lines (Hela and EMT6) than free curcumin. An in vivo biodistribution study revealed that the Cur-micelles displayed significantly enhanced accumulation inside the tumor of EMT6 breast tumor-bearing mice. More impressively, the Cur-micelles exhibited better antitumor activity, higher anti-angiogenesis effects and induced apoptosis on the EMT6 breast tumor model bearing mice than free curcumin. Furthermore, the Cur-micelles showed no significant toxicity towards the hemotological system, major organs or tissues in mice. Combining high antitumor activity and low toxic side-effects, the Cur-micelles developed here appear to be a highly attractive nanomedicine for effective, targeted cancer therapy.