抑癌基因PTEN蛋白在人胃癌中的表达与预后的关系

目的通过对胃癌及癌旁组织中PTEN蛋白表达水平检测,随访观察其生存率,初步探讨PTEN基因蛋白在胃癌发生发展过程中可能作用及对预后影响。方法用免疫组织化学技术检测53例胃癌标本的癌组织和癌旁组织基因组内PTEN蛋白表达水平改变,并统计分析PTEN蛋白表达与胃癌临床病理学参数的关系,随访观察其一年、三年、五年生存率。结果PTEN蛋白阳性表达均明确定位于胞浆,呈黄色或棕黄色颗粒。53例癌旁组织内PTEN蛋白表达情况:( )为18.8%、( )34.0%(、 )47.2%,总阳性率为100%,而在胃癌组织中(-)为34.0%、( )26.4%、( )24.5%、( )15.1%,总阳性率为66.0%,显著低于癌旁组织(P<0.005)。PTEN蛋白在胃癌组织中的阳性表达与患者的性别、年龄、肿瘤位置、肿瘤大小、有无癌栓等临床病理学指标无明显关系(P>0.05),而与浸润深度、淋巴结转移、分化程度PTNM分期呈显著相关(P<0.05)。在胃癌组织PTEN蛋白表达阳性胃癌患者中,其一年、三年、五年的生存率较PTEN蛋白表达阴性胃癌的患者生存率高,两者比较有显著性差异。结论PTEN蛋白异常表达在胃癌发生发展过程中可能有重要作用。

Expression of PTEN Protein in Human Gastric Carcinoma and Its Prognosis

Objective To study the role of PTEN mutation in the development of gastric carcinoma and its relationship with prognosis.Methods A panel of human primary gastric tissue with respect to the presence of PTEN mutation was examined by immunohistochemistry,and PTEN expression was analyzed with clinical pathologic characteristics of tumor and the patients' survival rate observed after one year,three years or five years.Results Immunohistochemistry staining showed that clearly brown staining was restricted to cytoplasm.The positive rate of PTEN protein in neighboring non-tumor mucosa was higher than those in gastric carcinoma(100% vs 66%,P<0.005).The expression level marked as(-),( ),( ),( ) in neighboring non-tumor mucosa group was 0%,18.9%,34.0%,47.2% and that in the gastric carcinoma group was 34%,26.4%,24.5%,and 15.1%,respectively(P<0.005).Decreased expression level of PTEN protein was significantly associated with tumor depth,lymph node metastasis,histologic grade and pTNM stage(P<0.05).However no significant relationship was found with gender,age,tumor location,tumor size,distant metastasis and presence of tumor thrombus(P>0.05).Conclusion Mutation of PTEN may be involved in tumorigenesis and progression of gastric carcinoma.For patients with positive mutation of PTEN protein,the survival rates for one year,three years or five years are significantly higher than those with negative mutation of PTEN protein.It is suggested that PTEN can be an objective marker for its pathological and biological behaviors of gastric carcinoma.