人脑胶质瘤U251细胞中hMLH1、hMSH2基因启动子区的甲基化状态研究  

Methylation status of promoter of mismatch repair gene hMLH1 and hMSH2 in glioma cell line U251

作　　者：陈新军[1] 袁先厚[1] 吴勉云[2] 江普查[1] 马超[1] 文志华[1] 

机构地区：[1]武汉大学中南医院神经外科,430071 [2]武汉科技大学医学院生物化学教研室

出　　处：《中华实验外科杂志》2007年第11期1300-1302,共3页Chinese Journal of Experimental Surgery

摘　　要：目的观察人脑胶质瘤U251细胞系中hMLH1、hMSH2基因启动子区的甲基化状态及其在肿瘤发生中的作用。方法采用甲基化特异性聚合酶链反应(MSP)法对人脑胶质瘤U251细胞系的hMLH1、hMSH2基因启动子CpG岛甲基化进行检测;培养人脑胶质瘤U251细胞系,MSP法检测加入5-aza-2’-deoxycytidine前后hMSH2基因在人脑胶质瘤U251细胞中的甲基化状态改变;逆转录-聚合酶链反应(RT-PCR)法检测加入5-aza-2’-deoxycytidine前后hMSH2在人脑胶质瘤U251细胞中的mRNA表达改变。结果人脑胶质瘤U251细胞中未发生hMLH1启动子甲基化,而发生了hMSH2启动子甲基化;5-aza-2’-deoxycytidine处理细胞株后,可逆转hMSH2启动子甲基化,细胞株的mRNA表达增加,加药前后的平均灰度比值分别为(0.40±0.18;0.85±0.32,P<0.01),差异有统计学意义。结论人脑胶质瘤U251细胞系中hMSH2基因启动子CpG岛高甲基化,5- aza-2’-deoxycytidine能完全逆转hMSH2基因高甲基化状态,可为临床诊断人脑胶质瘤提供新的检测指标和治疗靶点。Objective To explore the methylation status of hMLH1 and hMSH2 promoter region in glioma cell line U251 and its role in the oncogenesis. Methods Glioma cell line U251 cells were subjected to the methylation specific PCR （MSP） for examination of promoter methylation status of hMLH1 and hMSH2. The changes in the methylation status and the mRNA expression of hMSH2 gene in glioma cell line U251 were observed by MSP method and RT-PCR before and after treatment of5-aza-2＇ -deoxycytidine treatment. Results Promoter methylation of the hMSH2 gene was present in cell line U251, but that of the hMLH1 gene was absent. After treatment with 5-aza-2＇ -deoxycytidine,hMSH2 methylation was completely reversed,and the mRNA expression was increased in cell line. The content of hMSH2 mRNA had significant difference before and after treatment （0.40±0.18 vs 0.85±0.32,P 〈0.01 ）. Conclusion hMSH2 promoter （CpG island） hypermethylation exists in glimna cell line U251 ,abd hMSH2 methylation ceuld be completely reversed by 5-aza-2 ＇ -deoxycvtidine.

关 键 词：胶质瘤 碱基 启动子 DNA甲基化 

分 类 号：R739.4[医药卫生—肿瘤]