无机汞诱导人小细胞肺癌NCI_H446细胞凋亡的分子机制研究

The Molecular mechanisms of Methylmercury chloride inducing apoptosis in NCI-H446 cell

目的探讨无机汞(Inorganic mercury,IM)诱导NCI-H446细胞凋亡发生的分子机制。方法应用流式细胞术检测无机汞对NCI_H446细胞凋亡的影响;采用RT-PCR及Western Blot法检测无机汞作用NCI-H446细胞后促凋亡基因Bax、凋亡抑制基因Bcl-2、凋亡蛋白酶Caspase-3mRNA及蛋白水平的变化。结果不同浓度无机汞作用NCI-H446细胞后,随着剂量的升高可以看到凋亡率增加,无机汞组细胞Bcl-2mRNA及蛋白表达水平低于对照组,并存在着时间依赖性降低趋势,至24h达到最低;Bax及Caspase-3mRNA及蛋白表达水平均高于对照组,并存在着时间依赖性增高趋势,至24h达到最高。结论无机汞通过下调凋亡抑制基因Bcl-2mRNA水平、上调凋亡促进基因BaxmRNA水平,进而激活Caspase-3来调控NCI-H446细胞凋亡的发生。

Objective To investigate the possible molecular mechanism of Methylmercury chloride（MMC） inducing apoptosis in NCI_H446 cell.Methods Flow cytometry was used to examine the effects of MMC on the cell apoptosis.The expressions of Bcl-2,Bax and Caspase-3 in NCI-H446 cells were detected by RT-PCR and Western Blot after methylmercury chloride was used.Results Results The mRNA level of Bcl-2 in MMC group was lower than that of control group and had time dependence.It was the lowest at 24 h.The mRNA levels of Bax and Caspase-3 in MMC group were higher than those of control group,and had time dependence.They were the highest at 24 h.Conclusion MMC could induce NCI-H446 cells apoptosis in vitro.The mechanism is that Methylmercury chloride decreased the mRNA levels of apoptosis suppressor gene Bcl-2 and increased the mRNA levels of the pro-apoptotic gene Bax.