胃癌组织中PTEN和P-ERK的表达及相互关系

Study of expression and correlation between PTEN and P-ERK in gastric cancer

目的 :检测PTEN和P ERK蛋白在胃癌中的表达 ,并探讨其相互关系。方法 :应用免疫组化方法检测5 7例胃癌及其癌旁正常组织中PTEN和P ERK蛋白的表达情况。结果 :( 1)PTEN蛋白在胃癌中表达的阳性率( 61 4% )明显低于相应正常组织 ( 10 0 % ) (P <0 0 1) ,其表达水平与组织分化程度、浸润深度、淋巴结转移及TNM分期有关 (P <0 .0 5 )。 ( 2 )P ERK蛋白在胃癌中表达的阳性率 ( 84 2 % )明显高于相应正常组织 ( 12 3 % ) (P <0 0 1) ,其表达水平与浸润深度、淋巴结转移及TNM分期有关 (P <0 0 5 ) ,与分化程度无关 (P >0 0 5 )。 ( 3 )胃癌组织PTEN和P ERK蛋白表达之间呈明显负相关 (P <0 0 1)。结论 :提示PTEN和P ERK蛋白表达与胃癌生物学行为密切相关 ;在胃癌发生、发展过程中 ,可能是由于PTEN蛋白的低表达或失表达 ,不能有效抑制Ras/Raf/MEK /ERK信号通路的异常激活 ,使细胞发生癌变 ,并促进癌变细胞的浸润。

Objective To detect the expression of PTEN and P-ERK in human gastric cancer, and to study their correlation. Methods Expression of PTEN and P-ERK was examined in 57 gastric cancer and adjacent normal tissues by immunohistochemical technique. Results (1) The positive rate of PTEN was significantly lower in gastric cancer (61.4%) than that in normal tissues (100%) (P<0.01), and expression level of PTEN was related to histological differentiation, extent of infiltrating, lymphnode metastasis and TNM stage (P<0.05). (2) The positive rate of P-ERK was significantly higher in gastric cancer (84.2%) than that in normal tissues (12.3%) (P<0.01), and expression level of P-ERK was related to extent of infiltrate, lymphnode metastasis and TNM stage (P<0.05). No correlation were found between expression level of P-ERK and histological differentiation (P>0.05). (3) A significant negative relationship was observed between the expression of PTEN and P-ERK in gastric cancer (P<0.01). Conclusion The data suggest that the decrease or deletion of PTEN protein expression may not be able to effectively inhibit the over-activation of Ras/Raf/MEK/ERK signaling pathway, which will result in carcinogenesis, infiltrate and metastasis.