胃癌组织中p33ING1基因的表达及突变的检测

目的 研究p33~(ING1)基因表达与胃癌的发生、发展、预后的关系及p33~(ING1)基因突变在胃癌中的地位。方法 应用Evision免疫组化检测胃癌及癌前病变组织中的p33~(ING1)表达,采用聚合酸链-单链构象多态性(PCR-SSCP)分析法,检测胃癌中p33~(ING1)基因外显子2的突变。结果 胃癌中的p33~(ING1)蛋白表达阳性率为54.4％(56/103),远低于黏膜不典型增生组的94.4％(34/36)和正常组的100％(32/32),三者比较P<0.01。胃癌中的p33~(ING1)蛋白表达与胃癌浸润、远隔转移及分化相关(P<0.05);用PCR-SSCP方法检测到胃癌组织中有3例突变12％(3/25),位于外显子2区内,DNA测序为错义突变。结论 p33~(ING1)基因蛋白在胃癌组织中表达下降,有外显子2存在突变,p33~(ING1)基因在胃癌的发生、进展、预后有重要意义。

p33(ING1) gene expression and mutation in stomach cancer tissues and precarcinomatous tissues

Objective To analyze the relationship of p33 gene expression and p33ING1 exon-2 mutation to the pathogenesis, development and consequence of stomach cancer. Methods Envision immunohistochemical method was utilized to detect the p33ING1 expression in 103 specimens of stomach cancer, 36 specimens of stomach mucosal atypical hyperplasia, and 32 specimens of normal stomach mucosa. PCR-SSCP was utilized to detect p33ING1 exon-2 mutation in stomach cancer tissues. Results The p33ING1 expression rate in stomach cancer was 54.4% (56/103), significantly lower than that in precarcinomatous tissues (94.4% , 34/36, P < 0.01) and that in normal tissues (100% , 32/32, P < 0.01) . The p33 expression in stomach cancer was related to tumor growth, distant metastasis and tumor differentiation (all P < 0.05) . p33ING1 gene exon-2 mutation was detected in 3 cases of stomach cancer tissues (12% , 3/25) , and not in other tissues by PCR-SSCP method. Conclusion p33 G1 low expression, and gene p33ING1 exon-2 mutation may play an important role in the pathogenesis, development and consequence of stomach cancer.