地塞米松对人乳腺癌细胞系MCF-7细胞增殖及细胞周期的影响

目的:观察不同浓度的地塞米松(Dex) 对人乳腺癌细胞系(MCF-7) 细胞增殖、细胞周期分布及P21/WAF1表达的影响.方法:以不同浓度Dex(10-10～10-6 mol/L)处理细胞,采用活细胞计数法观察细胞增殖情况;测定碱性磷酸酶(AKP)活性;通过流式细胞仪技术,测定Dex作用后其细胞周期分布;通过蛋白印迹分析的方法检测Dex对p21/WAF1表达的影响.结果:Dex对MCF-7细胞的增殖有明显抑制作用, 10-7mol/L Dex作用5 d后活细胞计数为对照组的70%,细胞在G0/G1期停滞; Dex还可使MCF-7 细胞AKP活性增高,这种作用具有时间和剂量依赖性;Dex对p21/WAF1表达无明显影响.结论:Dex对MCF-7细胞有明显的增殖抑制作用,细胞在G0/G1期停滞.

Effects of dexamethasone on proliferation and cell cycle of human breast cancer cell line MCF-7

Objective:To study the effects of dexamethasone (Dex), a synthetic glucocorticoid, on the proliferation and cell cycle of human breast carcinoma cell line MCF-7. Methods: MCF-7 cells were treated with different concentrations of Dex (10~(-10)-10~(-6) mol/L). Cell proliferation was evaluated by viable cell count and alkaline phosphatase( AKP) activity was also determined. The cell cycle was examined with flow cytometry and p21/WAF1 expression was detected with Western blot analysis. Results: Dex inhibited the proliferation of MCF-7 cells, with the cell number being 70% of the control group 5 d after treatment with Dex(10~(-7) mol/L). Dex also induced G_0/G_1 arrest of MCF-7 cells phase. AKP activity increased significantly after treatment with Dex in a time- and dose-dependent manner. Dex had no obvious effect on p21/WAF1 expression. (Conclusion:) Glucocortocoids can obviously inhibit the proliferation of MCF-7 cells and induce G_0/G_1 phase arrest.