亚砷酸钠联合粉防己碱对乳腺癌MDA-MB-231细胞的增殖抑制作用及机制研究

目的:探讨亚砷酸钠联合粉防己碱对乳腺癌MDA-MB-231细胞的增殖抑制作用。方法:MTT法检测细胞活力，Annexin V-FITC/PI双染法检测细胞凋亡，Hoechst33258染色观察细胞染色质固缩情况，碘化丙啶PI单染法检测细胞周期，Western blot检测p-GSK3β、GSK3β及凋亡相关蛋白 PARP、bcl-2的表达。结果:不同浓度的亚砷酸钠或粉防己碱单用均可抑制MDA-MB-231细胞增殖（P＜0.01）；与单独用药相比，两药联合使用可显著增强细胞增殖抑制效果（P＜0.000 1）。两药联用可显著诱导MDA-MB-231细胞凋亡（P＜0.01），细胞凋亡率呈现浓度依赖性递增，并出现细胞核染色质固缩。联合用药浓度为亚砷酸钠10 μmol/L+粉防己碱4 μg/ml时，S期细胞所占百分比显著增高（P＜0.05）；联合用药浓度为亚砷酸钠15 μmol/L+粉防己碱4.5 μg/ml时，G2/M期细胞所占百分比显著增高（P＜0.001）。联合用药后，凋亡相关蛋白PARP的表达显著上调（P＜0.000 1）；bcl-2的表达显著下调（P＜0.05）；p-GSK3β、GSK3β蛋白表达均显著上调（P＜0.000 1）。 结论:亚砷酸钠联合粉防己碱对乳腺癌MDA-MB-231细胞具有增殖抑制作用，其机制与诱导细胞周期 S期、G2/M期阻滞、GSK3β蛋白水平上调及促进细胞凋亡有关，促凋亡作用与bcl-2蛋白水平下调、PARP蛋白水平上调有关。

Sodium arsenite combined with tetrandrine inhibits the proliferation of MDA-MB-231 cells in breast cancer and its mechanism

Objective:To investigate the effects of sodium arsenite combined with tetrandrine on proliferation inhibition in human breast cancer cell line MDA-MB-231.Methods:Cell proliferation was measured using MTT assay.Cell apoptosis was examined by Annexin V-FITC/PI double staining analysis.Chromatin condensation was observed by Hoechst33258 staining.Cell cycle was examined by PI staining.The expression of p-GSK3β,GSK3β and apoptosis-related proteins PARP,bcl-2 were detected by Western blot.Results:Both alone sodium arsenite and alone tetrandrine could inhibit the proliferation of MDA-MB-231 cells (P＜0.01).Compared with each drug alone,the combination could enhance the inhibition rate (P＜0.000 1).Apoptosis was induced significantly by the combination.Chromatin condensation was observed,and the apoptosis rate was dose-dependent.After treatment with NaAsO2 10 μmol/L+tetrandrine 4 μg/ml for 48 h,the rate of S phase was increased significantly (P＜0.05).After treatment with NaAsO2 15 μmol/L+tetrandrine 4.5 μg/ml for 48 h,the rate of G2/M phase was increased significantly (P＜0.001).After treatment with the combination,the expression levels of PARP,p-GSK3β,GSK3β were up-regulated (P＜0.000 1),while bcl-2 was down-regulated (P＜0.05).Conclusion:Sodium arsenite combined with tetrandrine could inhibit the proliferation of MDA-MB-231 cells.The mechanism was related to cell cycle S phase or G2/M phase arrest,the up-regulation of GSK3β protein,and apoptosis induction.