三氧化二砷对乳癌细胞系MDA-MB-468雌激素受体表达的影响

摘要

Aim:To study the DNA and protein change of estrogen receptor-α( Erα ) after treatment with different concentrations of arsenic trioxide in breast cancer cell MDA-MB-468. Methods: MDA-MB-468 cells were collected. MTT method was used to analyze cell growth activity after arsenic trioxide treatment by 24,48,72 h. Methylation-specific PCR was utilized to detect the methylation status of CpG island of the promoter of Erα gene and western blot to analyse expression of Erct protein. Results: Arsenic trioxide inhibits proliferation of MDA-MB-468 cells, which had the dose-effect and time-effect( Finteraction = 375. 603 ,Ftime =474. 827,P<0.001 ). CpG island of MDA-MB468 cells demethylated after treated by 1.0,2. 0,4. 0 μmol/L arsenic trioxide. The Erα protein of MDA-MB-468 cells was re-expressed after treated by 1.0, 2.0,4. 0μmol/L arsenic trioxide. Conclusion: Arsenic trioxide inhibits proliferation of MDA-MB-468 cells. Certain concentration of arsenic trioxide can demethylate the CpG island of the promoter of Erα and restores expression.%目的:探讨三氧化二砷(As2O3)对人雌激素受体α(ERα)阴性的乳癌细胞株MDA-MB-468进行药物诱导后ERα启动子CPG岛的甲基化状态及蛋白的变化.方法:常规培养MDA-MB-468细胞,采用MTT法检测0.5、1.0、2.0、4.0、8.0和16.0 mmol/L As2O3分别处理24、48和72 h后细胞的生长抑制率,甲基化特异性PCR检测1.0、2.0、4.0 μmol/L As2O3处理72 h后MDA-MB-468细胞 ERα启动子CpG岛的甲基化状态,Western blot检测1.0、2.0、4.0 μmol/L As2O3处理72 h后MDA-MB-468细胞ERα蛋白的表达情况.结果:As2O3可抑制MDA-MB-468细胞增殖,其作用呈时间和剂量依赖性(F浓度=375.603,F时间=474.827,P<0.001).经1.0、2.0、4.0 μmol/L As2O3处理后的MDA-MB-468细胞启动子CpG岛甲基化水平降低,ERα蛋白重新表达.结论:As2O3明显抑制MDA-MB-468增殖,适当浓度As2O3能诱导ERα去甲基化,使ERα阴性的MDA-MB-468细胞恢复表达ERα.