细胞外信号调节激酶在胃癌中的过表达与胃癌的恶性潜能相关

Increased expression of extracellular signal-regulated kinase in human gastric cancer

目的 探讨胃癌中细胞外信号调节激酶ERK 1和ERK 2蛋白的表达与活性及其与胃癌临床病理因素的关系。方法 用固定化蛋白质印迹法检测 42例胃癌及邻近正常胃粘膜中ERK 1和ERK 2蛋白及磷酸化ERK(P ERK)的表达 ;免疫组织化学法分析其在细胞内的定位。结果 胃癌中ERK 1和ERK 2的蛋白表达水平明显高于正常胃粘膜 (P <0 0 1) ;ERK蛋白表达水平与肿瘤大小及组织学分化无关 (P >0 0 5 ) ;Ⅲ、Ⅳ期胃癌中ERK 1和ERK 2蛋白表达水平高于Ⅰ、Ⅱ期胃癌 (P <0 0 5 ) ;有淋巴结转移胃癌中ERK 1和ERK 2蛋白表达水平高于无淋巴结转移胃癌 (P <0 0 5 ) ;侵犯浆膜胃癌中ERK 1和ERK 2蛋白表达水平高于无浆膜侵犯的胃癌 (P <0 0 5 ) ;ERK 1与ERK 2蛋白在胃癌中的表达呈线性正相关 (r=0 5 5 0 ,P <0 0 1)。ERK 1和ERK 2的蛋白表达水平与P ERK表达水平一致。ERK蛋白主要表达于细胞浆 ,胃癌组织中的表达量明显高于癌旁正常胃粘膜。结论 ERK 1和ERK 2蛋白的过表达可能在胃癌的发生发展过程中发挥重要作用 ,与胃癌TNM分期、浆膜侵犯及淋巴结转移有关。

Objective To investigate the expression of extracellular signal regulated kinase(ERK) in human gastric cancer and evaluate the relationship between ERKs protein level and clinicopathological parameters. Method Western blot was used to measure the activity and expression of ERK 1 and ERK 2 proteins and immunohistochemistry was used for localization in 42 gastric cancer patients.Results ERK 1 and ERK 2 protein levels increased in gastric cancer tissues in comparison to normal tissues ( P <0 01). Overexpression of ERK 1/2 was correlated to advanced TNM staging, lymph node involvement and serosa invasion in poorly differentiated gastric carcinomas. No statistical significant difference of ERK expression was found when stratified to tumor size or histological grade( P >0 05). Expression of ERK 1 and ERK 2 showed a positive linear correlation (r=0 550, P <0 01). Protein levels of ERK 1 and ERK 2 were consistent with that of P ERK. The immunohistochemistry demonstrated that the ERK proteins were mainly located in cytoplasm.Conclusion ERKs may play an important role in the development of gastric cancer.