【摘要】 目的探讨自噬抑制剂(Baf)在乳腺癌MCF-7细胞对依托泊苷(VP-16)的药物敏感性的影响。方法实验分为对照组(NC)、Baf组、VP-16和VP-16+Baf组。用MTT法检测细胞生存活力、GFP-LC3质粒转染后荧光显微镜检测绿色荧光的分布、Western blot检测蛋白表达和流式细胞仪检测细胞凋亡。结果 15μmol/L的VP-16使细胞活力降低,而在收集细胞前12 h时加入10 nmol/L的Baf进一步降低了细胞活力(P<0.01);VP-16明显增加MCF-7细胞的LC3Ⅱ的表达和GFP-LC3绿色荧光斑点的聚集,而减少了P62的蛋白表达;与VP-16组比较,VP-16+Baf组细胞P62的蛋白表达增多,凋亡蛋白cleaved-PARP的表达和细胞凋亡比例也明显增多(P<0.01)。结论 VP-16抑制乳腺癌细胞增殖的过程中诱导了保护性自噬,抑制自噬促进了凋亡性死亡,可以增加癌细胞对VP-16的敏感性。更多还原

【Abstract】 Objective To investigate the effects of bafilomycin A1( Baf) on the sensitivity of MCF-7 breast cancer cells to etoposide( VP-16). Methods The cultured cells were divided into normal control( NC),Baf,VP-16 and VP-16 + Baf groups. The viability of cells was determined with MTT assay. After GFP-LC3 plasmid transfection to the cells,the distribution of green fluorescence was observed by using fluorescence microscopy. The protein expression was assayed by Western blot and the apoptosis of MCF-7 cells was detected by flow cytometry. Results VP-16 at 15 μmol / L reduced the viability of cells. Baf( 10 nmol / L) which was added to treat the cells for 12 h before the cells collection reduced the viability of cells more than VP-16 used only( P < 0. 01). VP-16 obviously induced the expression of LC3Ⅱ and GFP-LC3 dots in MCF-7 cells,and decreased the expression of P62. Baf inhibited the autophagy induced by VP-16,and increased the expression of cleaved-PARP in MCF-7 cells and the apoptotic rates( P < 0. 01). Conclusions VP-16 reduced the viability of breast cancer cells and induced protective autophagy,and inhibition of autophagy promoted the apoptotic death and increased the sensitivity of cells to VP-16.更多还原