五溴联苯醚影响乳腺癌MCF-7细胞增殖和凋亡的机制探讨

Molecular mechanism of proliferation and apoptosis in breast cancer MCF-7 cells by penta-brominated diphenyl ethers

目的:观察环境化合物五溴联苯醚(Penta-brominated diphenyl ethers,5-BDE)影响人乳腺癌细胞MCF-7增殖和凋亡的分子生物学作用机制。方法:将MCF-7细胞在DMEM培养液中进行常规传代培养。采用MTT比色法观察5-BDE对MCF-7细胞增殖的影响,用逆转录聚合酶链反应(RT-PCR)技术和免疫组化方法检测5-BDE对Bcl-2和Bax基因表达的影响。结果:与溶剂对照组相比,在1×(10^(-8)～10^(-4))mol/L浓度范围内,5-BDE与1×10^(-8)mol/L雌二醇作用类似,可显著促进MCF-7细胞增殖(P<0.05),并表现出良好的剂量-效应和时间-效应关系。RT-PCR及免疫组化结果显示,5-BDE可促进MCF-7细胞Bcl-2和抑制Bax蛋白表达。结论:5-BDE可通过影响细胞增殖和凋亡相关调节基因Bcl-2和Bax表达而调节人乳腺癌细胞MCF-7的增殖和凋亡作用。

Objective：To investigate the molecular mechanisms of proliferation and apoptosis by penta-brominated Diphenyl Ethers through regulation of mRNA and protein expression of Bcl-2 and Bax in breast cancer MCF-7 cells. Methods： Human breast cancer MCF-7 cells were grown in DMEM medium,MTT assay was employed to investigate cell proliferation. RT-PCR and immunohistochemistry was performed to determine mRNA and protein expression of Bcl-2 and Bax,Results：Within the range of 1×（10^-8-10^-4） mol/L,5-BDEs stimulated proliferation in MCF-7 cells with a dose-dependent and time-dependent fashion. RT-PCR and immunohistochemistry analyses revealed that treatment with 1×（10^-8-10^-4）mol/L for 72h resulted in increased mRNA and protein expression of Bcl-2 and inhibition of Bax. Conclusion：5-BDE possessed estrogenic activity and could markedly stimulate proliferation in estrogen responsive breast cancer MCF-7 cells. Up-regulation of Bcl-2 mRNA and protein expression was suggested to be involved in this biological effect.