摘要
目的 研究HepG2肝癌细胞GSTP1基因启动子区甲基化与GSTP1基因表达的关系 ,并探讨普鲁卡因酰胺用于诱导因甲基化失活的GSTP1基因重新表达的可能性。方法 分别用 5 -杂氮 - 2′ -脱氧胞苷 (5 -Aza -CdR)和普鲁卡因酰胺处理HepG2细胞后培养 ,甲基化特异性PCR(MSP)检测细胞中GSTP1基因的甲基化状况 ,RT -PCR和Westernblot分别检测细胞中GSTP1mRNA和GST -π的表达。结果 HepG2细胞在去甲基化药物处理前 ,GSTP1基因完全甲基化 ,GSTP1基因不表达 ;药物处理后 ,普鲁卡因酰胺组和 5 -Aza -CdR组GSTP1基因有表达。结论 肝癌细胞GSTP1基因启动子区甲基化可抑制GSTP1基因表达 ,普鲁卡因酰胺与 5 -Aza
Objective\ To study the correlation between methylation of GSTP1 promoter and expression of π-class glutathione S-transferase, and to explore the possibility of re-expression of methylated and silenced GSTP1 gene in the HepG2 cell lines induced by procainamide.Methods\ After treatment of 5-Aza-2 '-deoxycytidine(5-Aza-CdR) and procainamide in cell lines, GSTP1 methylation in the HepG2 cell lines was determined by MSP and correlated with expression of the gene using reverse-transcription PCR and immunoblotting.Results\ DNA from HepG2 cell lines displayed complete GSTP1 methylation, and they failed to express GSTP1 mRNA and its corresponding protein product. The cell lines treated with the DNA methylation transferase inhibitor reversed the methylation, and restored GSTP1 mRNA and protein expression.Conclusions\ Methylation of GSTP1 promoter repress GSTP1 expression. Reversal of GSTP1 promoter methylation and reactivation of π-class glutathione S-transferase expression is induced by procainamide or 5-Aza-CdR in HepG2 cell lines.
