title: pH-sensitive micelles based on acid-labile pluronic F68-curcumin conjugates for improved tumor intracellular drug delivery.
abstract: Curcumin (Cur) is a highly pleiotropic anticancer agent that inhibits cell proliferation and induces apoptosis in cancer cells. A variety of nano-systems constituted by polymer-drug conjugates have been designed to overcome its shortages on water solubility, chemical instability, and poor bioavailability. However, most of them suffer from ineffective release of Cur in cancer cells in vivo. This work developed a novel flexible acid-responsive micelle formulation by covalently conjugating Cur on the hydrophilic terminals of pluronic F68 chains via cis-aconitic anhydride linkers. The synthesized F68-Cis-Cur conjugates can readily precipitate to form homogeneous micelles with average size about 100 nm in aqueous solution. In acid environments, F68-Cis-Cur conjugates would break down and subsequently release Cur rapidly, for the reason of pH-sensitive cleavage of cis-aconitic anhydride linkers. In vitro anticancer activity tests demonstrated that F68-Cis-Cur micelles induced higher cytotoxicity against both A2780 and SMMC 7721 cells than free Cur. It provided a larger decrease of mitochondrion membrane potential and induced cellular apoptosis. F68-Cis-Cur micelles remarkably increased cellular uptake of Cur than free Cur through caveolae-mediated endocytosis in an energy-dependent manner. This study demonstrates F68-Cis-Cur conjugation as a promising tool for improving intracellular drug delivery in cancer therapy.
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Taipa, Macau 999078, China.
authors.forename: Xiao-Bin
authors.initials: XB
authors.lastname: Fang
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Taipa, Macau 999078, China.
authors.forename: Jin-Ming
authors.initials: JM
authors.lastname: Zhang
authors.affiliation: School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Xie
authors.affiliation: School of Mathematics, University of Minnesota, Minneapolis, MN 55455, USA.
authors.forename: Di
authors.initials: D
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Taipa, Macau 999078, China.
authors.forename: Cheng-Wei
authors.initials: CW
authors.lastname: He
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Taipa, Macau 999078, China.
authors.forename: Jian-Bo
authors.initials: JB
authors.lastname: Wan
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Taipa, Macau 999078, China. Electronic address: mwchen@umac.mo.
authors.forename: Mei-Wan
authors.initials: MW
authors.lastname: Chen
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000737:chemistry; D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003474:Curcumin / Q000008:administration & dosage* / Q000737:chemistry; D016503:Drug Delivery Systems; D065546:Drug Liberation; D006801:Humans; D006863:Hydrogen-Ion Concentration; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008823:Micelles; D020442:Poloxamer / Q000008:administration & dosage* / Q000737:chemistry
chemical_list: D000970:Antineoplastic Agents; D008823:Micelles; D020442:Poloxamer; D003474:Curcumin
keywords: Cancer; Curcumin; Pluronic F68; Polymer–drug conjugate; pH-sensitive