胃癌组织中p16基因mRNA和p16蛋白的表达及临床病理意义

Expression of p16 mRNA and p16 Protein in Gastric Carcinoma and its Clinico pathological Significance

目的探讨ｐ１６基因在胃癌发生发展及预后判断上的意义。方法应用原位杂交和免疫组化方法检测６１例胃癌组织和４９例癌旁正常胃粘膜的ｐ１６ｍＲＮＡ和ｐ１６蛋白的表达。结果（１）胃癌组织中ｐ１６ｍＲＮＡ和ｐ１６蛋白的阳性率分别为５０．８％（３１／６１），７０．５％（４３／６１），而癌旁正常胃粘膜的阳性率均为１００％（４９／４９），１０例早期胃癌均有ｐ１６ｍＲＮＡ和ｐ１６蛋白的表达，而且在同一切片中也可以观察到分化较好或浸润浅层的癌细胞表达ｐ１６ｍＲＮＡ和蛋白，而分化较差、浸润深层的癌细胞则没有表达。ｐ１６ｍＲＮＡ和蛋白的表达强度与胃癌的分化程度、浸润深度、有无淋巴结转移及病人的生存期密切相关。（２）ｐ１６ｍＲＮＡ与ｐ１６蛋白表达具有显著相关关系（Ｐ＜０．０５），绝大多数具有ｐ１６ｍＲＮＡ表达的病例，均有ｐ１６蛋白的表达。结论（１）确有部分胃癌组织存在ｐ１６基因的失表达，且失表达发生在胃癌发生发展的晚期阶段。（２）胃癌组织中ｐ１６基因的无义突变和移码突变可能较为少见。

Objective\ To study the biologic significance of the expression of p16 gene in gastric carcinoma.\ Methods\ The expression of p16 mRNA and p16 protein of 61 gastric carcinomas and 49 para tumor non neoplastic mucosa were detected by in situ hybridization and immunohistochemical method.\ Results\ (1)The positive rate of p16 mRNA and p16 protein in tumor tissue was 50%(31/61) and 70 5%(43/61) respectively,with being significantly different(P<0 05) when compared with the 100%( 49/49) positive rate of non neoplastic mucosae. 10 early gastric cancer all expressed p16 mRNA and p16 protein. Furthermore,we observed the phenomenon that p16 mRNA and p16 protein were expressed in better differentiated or shallower invasing tumor cells but not expressed in poorer differentiated or deeper invasing tumor cells in the same sections. \ The expression intensity of p16 mRNA and p16 protein were associated with tumor differention,invasion,lymphnodes metastasis and patient's prognosis(P<0 05). (2)The expression of p16 mRNA and p16 Protein was significantly interrelated to each other(P<0 05),the majority of tumors with p16 mRNA expression exhibited detectable p16 protein.\ Conclusion\ (1)Loss of p16 expression indeed exist in some gastric carcinoma tissues,and is a late event in the development of gastric carcinomas. (2)Nonsense mutations and frameshift mutations are relatively seldom among various forms of p16 gene mutations.