人胃癌Runx3基因CpG岛甲基化的关键位点和演进  

Critical regions and spreading of the Runx3 CpG island methylation in human gastric cancer

作　　者：宋军民[1] 刘晓梅 李岩[1] 韩成波[3] 

机构地区：[1]中国医科大学附属盛京医院消化内科,辽宁省沈阳市110004 [2]中国医科大学附属盛京医院中心实验室,辽宁省沈阳市110004 [3]中国医科大学附属盛京医院肿瘤科,辽宁省沈阳市110004

出　　处：《世界华人消化杂志》2008年第2期212-216,共5页World Chinese Journal of Digestology

摘　　要：目的:研究人胃癌Runx3基因CpG岛甲基化的关键位点和演进.方法:应用MSP法和Western blot法分别检测26例人胃癌和相应的癌旁正常组织标本Runx3基因CpG岛从5′区向转录起始点方向连续6个位点的甲基化状态和Runx3蛋白的表达.结果:根据MSP的结果计算出上述连续6个位点的甲基化阳性率,结果随着向转录起始点方向的演进,各位点甲基化的阳性率逐渐降低,胃癌组和癌旁组从第3位点开始出现差异,至第5和第6位点差异显著(P<0.05);按照胃癌分化程度分组,低分化组与高分化组在3-6位点差异显著(P<0.05).胃癌组与癌旁组Runx3蛋白表达水平(0.499±0.106 vs 0.721±0.080)以及低分化组与高分化组(0.437±0.053 vs 0.617±0.073)Runx3蛋白表达水平均存在显著差异(P<0.01).结论:人胃癌Runx3基因CpG岛的甲基化从5′区向转录起始点方向演进,甲基化的演进与肿瘤的分化程度有关;转录起始点部位可能为Runx3基因甲基化的关键位点.AIM： To investigate the critical regions and spreading of the Runx3 CpG island methylation in human gastric cancer. METHODS： MSP and Western blot were used for 26 human primary gastric cancer samples and corresponding non-neoplastic gastric mu cosa to detect the methylation status in successive six regionsranging from the most 5′ region to the transcription start site within the Runx3 CpG island and the expression levels of Runx3 protein, respectively. RESULTS： The methylation frequencies in the successive six regions calculated by the results of MSP decreased gradually with the regions spreading to the transcription start site. The differences between cancer group and non-neoplastic group arose in the 3rd region, and became significant in the 5th and 6th regions （P 〈 0.05）. When the grouping was related to the differentiation extent, the differences were significant in the 3rd-6th regions between poorly differentiated group and well differentiated group （P 〈 0.05）. As far as the expression levels of Runx3 protein were concerned, the differences were significant between gastric cancer group and non-neoplastic group （0.499 ± 0.106 vs 0.721 ± 0.080, P 〈 0.01）, as well as between poorly differentiated group and well differentiated group（0.437 ± 0.053 vs 0.617 ± 0.073, P 〈 0.01）. CONCLUSION： Methylation of the Runx3 CpG island spreads from the most 5′ region to the transcription start site in human gastric cancer, and the spreading is related to the differentiation extent of tumor. The transcription start site may be a critical region for the methylation of Runx3.

关 键 词：RUNX3 胃癌 甲基化 甲基化特异性聚合酶链反应 免疫印迹法 

分 类 号：R735.2[医药卫生—肿瘤]