Inhibitory effect of curcumin liposome on PC-3 human prostate cancer cells

Abstract

Objective To investigate anti-tumor efficacy and the biochemical mechanisms trig-gered by a new delivery system of curcumin liposome in PC-3 human prostate cancer cells.Methods The curcumin liposomes were prepared by thin film-hydration methods,then were used to treat human PC-3 cells.The survival of the treated cells was analyzed by methyl thiazol tetrazolium (MTT) assay.Cellular uptake study of curcumin liposomes was analyzed by fluorescence microscope and high performance liquid chromatography (HPLC).Moreover,the expression of protein of matrix metalloproteinase (MMP)-2 corre-lated to invasion was detected by Western blotting,and MMP-2 mRNA levels by reverse transcription-poly-merase chain reaction (RT-PCR).Results The cell proliferation was inhibited by curcumin liposomes in a dose-and time-dependent manner,and the cells became round in shape.Antiproliferative efficacy in PC-3 cells exhibited the order curcumin liposome ＞ curcumin,and there was significant difference between 60 μmol/L group and 100 μmol/L group (P ＜ 0.05),whereas liposome alone had no effect.The results of cellular uptake showed incorporated curcumin preserved its fluorescence intensity for longer time than the free curcumin.The expression of MMP-2 and the level of MMP-2 mRNA were down-regulated with drug concentrations.The expression level of MMP-2 was reduced 15.30％,35.63％ and 44.80％ at 20,60 and 100 μmol/L of free curcumin treatment,respectively.Meanwhile,the expression level of MMP-2 was re-duced 19.40％,45.40％ and 55.10％ at the same concentration of curcumin liposome treatment,respec-tively.The inhibition rates of curcumin liposome was higher than free curcumin(P ＜ 0.05).Conclusion Curcumin liposomes significantly enhanced the PC-3 cell uptake of encapsulated drug,which also resulted in increased antiproliferative activity of curcumin,and the inhibition of invasion in PC-3 cells may be relat-ed to down-regulation of MMP-2 levels.Curcumin liposomes have a significantly prolonged biological activity and demonstrated therapeutic efficacy comparable to free curcumin. Key words: Curcumin liposomes; Prostate cancer; Matrix metalloproteinase-2