磷酸化修饰对p53线粒体作用的影响以及与卵巢癌顺铂耐药的关系

目的探讨磷酸化修饰对p53直接线粒体转移的影响以及在顺铂诱导的卵巢癌细胞凋亡中的作用以及与卵巢癌顺铂耐药的关系。方法应用Western Blot检测顺铂作用前后卵巢癌顺铂敏感细胞OV2008、A2780s和顺铂耐药细胞C13＊、A2780cp的线粒体和细胞浆中Smac蛋白含量以及线粒体和全细胞中磷酸化p53（P-p53）的含量,并应用Hoechst染色法检测卵巢癌细胞的凋亡率。结果顺铂能引起卵巢癌敏感细胞OV2008、A2780s线粒体释放Smac至胞浆并引起细胞凋亡,但在C13＊和A2780cp中无此反应。顺铂处理后进入卵巢癌敏感细胞线粒体中的p53蛋白为磷酸化的p53。结论顺铂能引起p53转移至线粒体并导致卵巢癌敏感细胞线粒体释放Smac至胞浆,促进卵巢癌细胞的凋亡,并且磷酸化修饰作用可以影响p53的直接线粒体功能,与卵巢癌化疗耐药有关。

The relationship between the phosphorylation of p53 and the p53 directly mitochondrial translocation in cisplatin-induced apoptosis in ovarian cancer cells

Objective： To study the influence of phosphorylation on p53 direct mitochondrial translocation in cisplatin-induced apoptosis in ovarian cancer cells and the relationship between this and chemoresistance in ovarian cancer.Methods： Chemosensitive（OV2008 and A2780s） and –resistant（C13＊ and A2780cp） ovarian cancer cells were treated with CDDP.Mitochondrial and cytoplastic Smac contents,as well as whole cell P-p53 contents,were determined by Western blot.CDDP-induced apoptosis was measured by Hoechst staining.Results： CDDP induced mitochondrial Smac release and apoptosis in chemosensitive cells（P0.05）,but not resistant cells（P0.05）.After CDDP treatment,the mitochondrial p53 detected in chemosensitive cells is phosphorylated,but in chemoresistant cells phosphorylated p53 is undetectable.Conclusion： Cisplatin induces mitochondrial Smac release to cytoplasm in chemosensitive cells.Phosphorylation of p53 is related to the p53 direct mitochondrial accumulation in chemosensitive cells after CDDP treatment,and confers resistance in ovarian cancer cells.