食管鳞状细胞癌中PTPN6的表达及与临床病理特征的关系

目的检测食管鳞状细胞癌(esophageal squamous cell carcinoma,ESCC)中非受体型PTPN6基因的表达,探讨其与ESCC临床病理特征及预后的关系。方法采用RT-qPCR法检测食管癌细胞和71例ESCC及癌旁正常组织中PTPN6基因mRNA的表达;应用Western blot法和免疫组化SP法检测食管癌细胞和ESCC及癌旁正常组织中PTPN6蛋白的表达;按ESCC组织中PTPN6的蛋白表达分为阳性组和阴性组,行Kaplan-Meier生存曲线分析,并通过Cox风险比例模型对其他变量进行校正。结果与正常食管上皮细胞相比,PTPN6 mRNA和蛋白在食管癌细胞中表达下调(P<0.05);ESCC组织中PTPN6 mRNA相对表达量显著低于癌旁正常组织(1.000±0.001)vs(1.815±0.386),t=13.533,P<0.05];PTPN6 mRNA表达与患者TNM分期、病理分级及淋巴结转移有关(P<0.05)。ESCC中PTPN6的阳性率为32.4%(23/71),明显低于癌旁组织(P<0.05);PTPN6蛋白表达与患者TNM分期、病理分级及淋巴结转移密切相关(P<0.05)。Kaplan-Meier结果显示,PTPN6低表达与患者生存时间有关(P<0.05)。多变量Cox模型校正后,PTPN6蛋白表达对患者预后有影响(OR=2.694,P<0.05)。结论PTPN6基因在食管癌细胞系及ESCC组织中表达沉默,其与食管癌的发生、发展密切相关,有望成为ESCC患者预后评估的指标。

Expression of PTPN6 and its correlation with clinicopathological characteristics and prognosis in esophageal squamous cancer cell

Purpose To detect the expression of PTPN6 in esophageal squamous cancer(ESCC),and to explore the relationship between PTPN6 expression and clinicopathologic parameters and prognosis of ESCC patients.Methods The expression level of PTPN6 mRNA in esophageal cancer cell lines and paired para-cancerous ESCC tissues(n=71)were detected by RT-qPCR.The expression levels of PTPN6 protein in esophageal cancer cell lines and paired para-cancerous ESCC tissues(n=71)were detected by Western blot and immunohistochemistry of SP method respectively.According to the protein expression of PTPN6 in ESCC tissue,it was divided into PTPN6 positive expression group and negative expression group,and the relationship between PTPN6 expression and the overall survival of ESCC patients was investigated,and the other variables were adjusted by Cox risk propotional model.Results The PTPN6 mRNA and protein were down-expressed in esophageal cancer cell lines compared with normal human esophagus epithelial cell(P<0.01).PTPN6 mRNA expression in ESCC tumor tissues was significantly decreased compared to corresponding normal tissues(1.000±0.001)vs(1.815±0.386),t=13.533,P<0.05)].The results of immunohistochemistry showed that the positive protein expression frequency of PTPN6 in ESCC tissues was significantly(32.4%)lower than that in normal tissues(P<0.05).The expression of PTPN6 mRNA and protein in ESCC tissues was associated with TNM stage,tumor pathological grade,and lymph node metastasis(P<0.05).The result of Kaplan-Meier showed down-expression of PTPN6 was associated with prognosis of ESCC.After Cox model modification,the overall survival was affected by the expression status of PTPN6 protein(OR=2.694,P<0.05).Conclusion The down-expression of PTPN6 in ESCC may be a predict marker for poor prognosis and PTPN6 may be a potential target of ESCC treatment.