摘要
目的 通过研究胃癌及其癌前病变中微卫星不稳定性与错配修复基因hMSH2蛋白表达 ,来揭示微卫星不稳定性在胃癌演化过程中可能作用机制 ,并探讨导致胃癌中微卫星不稳定性的基因机制。方法 用PCR方法检测 5个微卫星位点MSI表现 ;并通过免疫组化SP法检测hMLH1、hMSH2错配修复蛋白的表达。结果 胃癌组、慢性胃炎组中MSI的阳性率分别为 5 8 82 %(30 5 1) ,2 1 0 5 %(12 5 7)。肠型胃癌与弥漫型胃癌的MSI阳性率间差别有显著性意义 (P <0 0 5 )。在所有标本中仅检测到 1例hMSH2表达缺失 ,异常表达的病例为胃乳头状腺癌。结论 MSI在散发性胃癌的发生及发展过程中均起到了一定作用 ,hMLH1启动子区异常甲基化是导致胃癌MSI的重要因素。
Objective To study the relationship among microsatellite instability (MSI),the expression of hMLH1 and methylation of the hMLH1 promoter in gastric cancer and precancerous lesions,and explore their action in gastric carcinogenesis and the molecular mechanism in cancer development.Methods 5 microsatellite loci were analyzed for MSI by PCR.Immunohistochemistry was used to detect the expression of hMSH2 protein.Results The incidence of MSI was 58.82%(30/51),21.05%(12/57) in cancer and chronic gastritis respectively.In gastric carcinoma specimens,the frequency of MSI in intestinal type gastric carcinomas(75%) was significantly higher than that in diffuse type(P<0.05).There was only one hMSH2 expression absent sample(1/108) was detected in the total specimens,which was well-differentiated papillary adenocarcinoma.Conclusion These results suggested that MSI may be an early important incident in gastric tumorigenesis.The abnormal expression of mismatch repair gene hMSH2 may have no major responsibility for MSI.
出处
《中国全科医学》
CAS
CSCD
2002年第12期963-965,共3页
Chinese General Practice
