胃癌组织中RKIP基因启动子甲基化及蛋白表达

Promoter methylation and expression of RKIP gene in patients with gastric carcinoma

目的探讨胃癌组织中RKIP基因启动子甲基化及蛋白的表达,分析RKIP基因启动子甲基化及蛋白表达与胃癌生物学行为的关系。方法采用甲基化特异性PCR(methylation-specific PCR,MSP)技术和免疫组化SP法检测45例胃癌组织、21例癌旁胃黏膜组织中RKIP基因启动子甲基化及蛋白的表达。结果胃癌及癌旁胃黏膜组织中RKIP基因启动子的甲基化阳性率分别为48.89%和4.8%(P<0.05);RKIP蛋白在胃癌及癌旁胃黏膜组织中的阳性率分别为42.22%和90.48%(P<0.05);RKIP基因启动子甲基化及蛋白的表达分别与胃癌的分化程度及淋巴结转移有关(P<0.05)。RKIP基因启动子甲基化与蛋白表达呈明显负相关(P<0.05)。结论 RKIP基因启动子的异常甲基化是引起蛋白表达缺失的原因之一,RKIP蛋白表达缺失与胃癌的发生、发展有关。

Purpose To investigate the correlation between promoter methylation of RKIP and the clinicopathological features of gastric carcinoma and to analyze the correlation between promoter methylation of RKIP and expression of RKIP. Methods The protein ex- pression and promoter methylation of RKIP were detected in 45 cases of surgically reseeted gastric carcinoma specimens and 21 cases of corresponding normal tissues using the immunohistehemistry SP method and methylation-specific PCR （MSP）. Results The positive rate of promoter methylation of RKIP was 48. 89% in gastric carcinoma tissues and 4.8% in adjacent tissues （P 〈 0.05 ）. The positive rate of the expression of RKIP protein was 42.22% in gastric carcinoma tissues and 90.48% in adjacent tissues （P 〈 0.05 ）. The pro- tein expression and promoter methylation of RKIP were correlated with the degree of differentiation and lymph node metastasis （P 〈 0. 05）. Expression of RKIP protein in gastric carcinoma was associated with promoter methylation of RKIP. Conclusions Promoter abnormal methylation of RKIP may be one reason of the deletion of expression of RKIP protein, which correlates with occurrence and development of gastric carcinoma.