5-氟尿嘧啶联合米非司酮对人宫颈癌SiHa细胞增殖的影响及作用机制研究

Effect of 5-fluorouracil combined with mifepristone on cell proliferation of human cervical cancer cell line SiHa and its mechanism

目的:体外研究5-氟尿嘧啶(5-fluororacil,5-Fu)联合米非司酮(mifepristone,MIF)对人宫颈癌SiHa细胞株的增殖抑制作用及可能的作用机制。方法:体外培养人宫颈鳞癌SiHa细胞株,采用MTT法检测不同浓度MIF、5-Fu单药以及两药联合作用对SiHa细胞增殖率的影响;采用FCM分析两药合用对SiHa细胞凋亡率及细胞周期分布影响;蛋白质印迹法检测药物处理后SiHa细胞中p53、Bax和Bcl-2蛋白表达的变化。结果:不同浓度5-Fu和MIF单药对SiHa细胞增殖均有抑制作用(P<0.05),且呈浓度和时间依赖性。5-Fu联合MIF作用于SiHa细胞可增强5-Fu对SiHa细胞的增殖抑制(P<0.05),且对MIF的作用浓度呈剂量依赖作用;蛋白质印迹法检测结果显示,联合用药组能使p53和Bax蛋白表达上调,Bcl-2蛋白表达下调,呈浓度依赖性。结论:MIF能增强5-Fu对SiHa细胞的增殖抑制和诱导凋亡作用,其机制可能与上调p53和Bax蛋白,下调Bcl-2蛋白表达有关。

Objective： To investigate the inhibitory effect of 5-fluorouracil （5-Fu） combined with mifepristone （MIF） on the cell proliferation of human cervical cancer cell line SiHa in vitro, and to explore the possible mechanism. Methods： SiHa cells were cultured in vitro. The proliferation inhibitory rates of SiHa cells treated with different concentrations of MIF or 5-Fu alone and the combination of MIF and 5-Fu were detected by MTT assay. The changes of apoptosis rate and the cell cycle of SiHa cells were determined by flow cytometry. The expression levels of p53, Bcl-2 and Bax proteins in SiHa cells were examined by Western blotting. Results： Different concentrations of MIF or 5-Fu could inhibit the proliferation of SiHa cells in a dose- and time-dependent manner （P0.05）. 5-Fu in combination with different concentrations of MIF could significantly enhance this inhibitory effect （P0.05） in a dose-dependent manner. The expression levels of p53 and Bax proteins were increased while the expression level of Bcl-2 protein was decreased in SiHa cells after treatment with 5-Fu plus MIF, and these effects were in a dose-dependent manner. Conclusion： MIF can enhance the inhibitory effect of 5-Fu on SiHa cells, and promote the apoptosis of SiHa cells induced by 5-Fu. The mechanism may be associated with the down-regulation of Bcl-2 protein and up-regulation of p53 and Bax proteins.