Objective: To explore the trichloroethylene-induced alteration of methylation on the promoter region of SET and related mechanisms in hepatic L-02 cells. Methods: L-02 cells were treated with different concentrations of TCE(0 mmol/L, 1 mmol/L, 2 mmol/L, 4 mmol/L, 8 mmol/L) for 24 h. The genomic DNA were then extracted and modified by bisulfite sodium. The DNA methylation was then analyzed using bisulfite sequencing PCR (BSP). Results: The overall methylation on promoter region of SET was decreased along with the increased concentrations of TCE in hepatic L-02 cells. Moreover, 73 CpG islands were found abnormally altered, among which 9 were predicted in transcriptional factor binding regions. Conclusion: The decreased levels of CpG islands in the transcriptional factor binding region may contribute to the elevation of SET in TCE-induced hepatotoxicity.
目的： 研究三氯乙烯（Trichlorethylene，TCE）致肝细胞毒性中SET基因启动子区甲基化水平的改变。 方法： 培养L-02肝细胞，使用0、1、2、4、8 mmol/L浓度的TCE处理24 h，提取细胞基因组DNA，进行亚硫酸氢盐修饰，用PCR扩增目标序列，重亚硫酸氢盐测序法（BSP）分析TCE作用下肝细胞中SET基因启动子区甲基化状态。 结果： 与对照组比较，TCE处理后L-02肝细胞中SET基因启动子区甲基化水平下降，且随着TCE染毒浓度的增加，SET基因启动子区甲基化水平递减。对SET启动子区甲基化差异位点进行分析发现，差异有统计学意义的甲基化位点有73个，已知转录因子结合位点9个。 结论： TCE致L-02肝细胞毒性中SET基因启动子区甲基化水平下降，影响转录因子的结合，继而使SET蛋白表达升高。.
Keywords: DNA methylation; L-02 cells; Patient SE translocation; Trich loroethylene.