Runx3、Rassf1a基因启动子在胃癌组织中的高甲基化及Dnmt1的表达  

Relationship between promoter methylation of the Runx3 and Rassf1a genes and Dnmt1 expression in gastric cancer

作　　者：姜相君[1] 初蕾蕾[1] 崔艳欣[1] 宋明全[1] 解祥军[2] 田字彬[3] 

机构地区：[1]青岛大学医学院附属青岛市市立医院消化内二科,山东省青岛市266011 [2]青岛大学医学院附属青岛市市立医院消化内一科,山东省青岛市266011 [3]青岛大学医学院附属医院消化内科,山东省青岛市266003

出　　处：《世界华人消化杂志》2012年第35期3457-3463,共7页World Chinese Journal of Digestology

基　　金：青岛市科技局基金资助项目;No.2012-1-3-1-(10)~~

摘　　要：目的:探讨人类相关转录因子3(human runt-related transcription factor 3,Runx3)、Ras相关区域家族1A(ras-association domain family 1a,Rassf1a)基因启动子区的甲基化和甲基转移酶1(DNA methyltransferase 1,Dnmt1)基因的表达与胃癌发生的关系及临床意义.方法:采用甲基化特异性聚合酶链反应(meth-ylation specific PCR,MSP)检测68例胃癌组织及其相应癌旁正常组织中Runx3、Rassf1a基因启动子区甲基化状态;同时应用实时荧光定量逆转录-多聚合酶链反应(real-time RT-PCR)和免疫组织化学SP法分别检测基因的Runx3、Rassf1a、Dnmt13个基因mRNA和蛋白的表达情况.结果:胃癌组织中Runx3、Rassf1a基因的甲基化阳性率较正常组织明显升高(45.59%vs10.29%;64.70%vs7.35%).胃癌组织中Runx3和Rassf1a mRNA阳性表达率明显低于正常组织(36.76%vs100%;27.94%vs97.06%),而胃癌组织中Dnmt1 mRNA阳性表达率则明显高于正常组织(80.88%vs17.65%),差异均有统计学意义差异.胃癌组织与正常组织RUNX3、RASSF1a、DNMT1蛋白与mRNA表达基本相一致.Runx3 mRNA、Rassf1a mRNA阴性表达的胃癌组织中其基因启动子的甲基化率较阳性表达者明显升高(72.09%vs0;85.71%vs2.94%),差异具有统计学意义.胃癌组织中RUNX3、RASSF1a与DNMT1蛋白的表达均呈负相关(r=-0.627,P<0.0001;r=-0.477,P<0.0001).结论:Runx3、Rassf1a基因启动子区的高甲基化及Dnmt1基因高表达可能与胃癌发生有关.AIM：To analyze the promoter methylation of the human runt-related transcription factor 3 （Runx3） and ras-association domain family 1a （Rassf1a） genes and Dnmt1 protein expression in gastric cancer and to analyze their relationship with gastric carcinogenesis. METHODS：Methylation status of the Runx3 and Rassf1a genes in 68 gastric carcinoma tissues and 68 paired surgical marginal normal gastric tissues was detected using methylation-specific PCR. Real-time RT-PCR was used to detect the expression of Runx3, Rassf1a, and Dnmt1 mRNAs, and immunohistochemistry was used to detect the expression of RUNX3, RASSF1a, and DNMT1 proteins in the above samples. RESULTS：The positive rates of promoter methylation of the Runx3 and Rassf1a genes were significantly higher in gastric cancer than in normal tissue （45.59% vs 10.29%; 64.70% vs 7.35%; both P 0.0001）. The positive rates of Runx3 and Rassf1a mRNA expression in gastric cancer were significantly lower than those in normal tissue （36.76% vs 100%; 27.94% vs 97.06%; both P 0.0001）, while that of Dnmt1 mRNA expression was higher compared to normal tissue （80.88% vs 17.65%, P 0.0001）. The expression patterns of RUNX3, RASSF1a, and DNMT1 proteins were consistent with those of Runx3, Rassf1a, and Dnmt1 mRNAs. The negative rates of Runx3 and Rassf1a mRNA expression in gastric cancer were significantly higher in the methylation group than in the non-methylation group （72.09% vs 0%; 85.71% vs 2.94%; both P 0.0001）. There was a negative correlation between the expression of RUNX3 and RASSF1a proteins and that of DNMT1 protein in gastric cancer tissue （r = -0.627, P 0.0001; r = - 0.477, P 0.0001）. CONCLUSION：The promoter methylation of the Runx3 and Rassf1a genes and high expression of Dnmt1 may be associated with the occurrence of gastric cancer.

关 键 词：胃癌 甲基化特异性PCR RUNX3 RASSF1A DNMT1 

分 类 号：R735.2[医药卫生—肿瘤]