Runx3基因在胃癌中的表达及其表达下调机制  

Runx3 gene expression in gastric carcinoma and its mechanism of down-regulation

作　　者：曾超[1] 贺修胜[1] 罗桥[1] 赵帅[1] 邓敏[1] 

机构地区：[1]南华大学肿瘤研究所,湖南省衡阳市421001

出　　处：《世界华人消化杂志》2006年第3期250-255,共6页World Chinese Journal of Digestology

基　　金：国家自然科学基金资助项目;No.30470967~~

摘　　要：目的:观察Runx3基因在人胃癌组织及相应正常胃组织中的表达分布特点,并对其表达下调的机制进行初步研究．方法:对25例胃癌标本进行DNA、RNA和蛋白的提取,利用单链构象多态性(SSCP)和微卫星法,检测Runx3基因突变和缺失情况．用 MSP(methylation specific PCR)检测25例胃癌标本及细胞株(MGC803,SGC7901)的甲基化状态．分别以蛋白印迹法(western blot)和逆转录聚合酶链反应(RT-PCR),检测Runx3蛋白质和mRNA水平．结果:在25例胃癌标本中发现一例杂合性缺失,未发现Runx3第三外显子突变．MSP法检测胃癌标本中55％(14/25)发生启动子区域的甲基化,同时在胃癌细胞株MGC803中Runx3 基因发生了部分甲基化．Western blot和RT- PCR发现Runx3在胃癌组织中表达明显低于相应正常胃组织(蛋白:50 178±14 404 vs 95 020±43 136,P<0．01;mRNA:0．66±0．31 vs 1．06±0．34,P<0．01)．结论:Runx3基因在胃癌组织中表达较正常组织明显下调,提示该基因与胃癌的发生和发展有关．Runx3基因表达下调的机制主要是因为启动子区域甲基化．AIM： To investigate level of Runx3 expression in gastric carcinoma, and to explore the main mechanism of Runx3 down-regulation. METHODS： DNA, RNA and protein were extracted from 25 gastric carcinoma specimens. Single strand conformation polymorphism （SSCP） and microsatellites were used to detect the mutation and loss of heterozygosity （LOH） of Runx3 gene. The methylation status of Runx3 gene was examined by methylation-specific polymerase chain reaction （MS-PCR）. The Runx3 mRNA and protein were detected by reverse transcription polymerase chain reaction （RT-PCR） and Western blot. RESULTS： LOH was detected in only 1 of 25 specimens, and no mutation in exon3 of Runx3 was found. Methylation of Runx3 promoter region was confirmed in 55% （14/25） specimens and part of gastric cancer cell line MGC803. RT- PCR and western blot indicate expression of Runx3 in gastric carcinoma were lower than that in corresponding normal stomach tissue CONCLUSION： The expression of Runx3 gene is down-regulated in gastric carcinoma, suggesting a possible involvement of Runx3 gene in carcinogenesis and progression of gastric cancer. The main mechanism of this down-regulation in Runx3 expression was related to the methylation of its promoter region.

关 键 词：胃癌 突变 甲基化 

分 类 号：R735.2[医药卫生—肿瘤]