【摘要】 应用S—P法检测116例胃癌和53例胃癌前病变的GST－π表达和限制性内切酶及PCR、Southern印迹方法检测14例胃癌及其相应正常胃粘膜GST－πDNA5’端调控区CCGG特定位点的甲基化水平。GST－π阳性率：正常胃粘膜10％（4／39），胃癌77％（89／116），肠上皮化生76％（19／25），不典型增生89％（25／28）。GST－π在胃癌及癌前病变中的表达较正常胃粘膜增高（P＜0．01）。胃癌组织中GST－π基因较正常胃粘膜呈现高度去甲基化（P＜0．01），胃癌GST-π基因5’端调控区低甲基化与其GST－π表达增加里相关性（P＜0．05）。GST－π在胃癌及癌前病变中的表达与胃癌的发生、发展密切相关。GST－π可作为胃癌的肿瘤相关抗原；GST－π基因5’端调控区低甲基化可能是GST－π高表达的分子机制。更多还原

【Abstract】 GST-π was detected in 116 human gastric carcinomas and 53 precancerous lesions with S-P immunohistochemical methods using GST-π monoclonal antibody. The methylation state of the 5’ end regulatory sequence CCGG site of GST-π gene was also investigated by means of restriction endonudease analysis. PCR and Southern blotting methods in 14 human gastric carcinomas and normal gastric mucosas. The positive rate of GST-π in normal gastric mucosa,intestinal metapla sia, atypical hyperplasia and gastric carcinoma were 10 % (4/39), 76 % (19/25), 89 % (25/28), 77 % (89/116) respectlvely, The positive rate in human gastrlc carcinomas and precancerous lesions were markedly hlgher than that of normal gastric mucosas (P<0. 01 ). The GST-π DNA from gastric carclnomas was substantially hypomethylated (P<0.0l ). Close correlation existed between overexpression of GST-π and hypomethylatlon of GST-π DNA in gastric carcinomas (P<0. 05 ).Hypomethylation of GST-π gene might be molecular mechanism responsible for overexpression of GST-π更多还原