OCT4在膀胱癌中的表达及其临床意义

目的检测干细胞标记物OCT4在膀胱癌中的表达,并探讨其与临床病理因素及肿瘤转移的相关性。方法采用Westernblotting、qRT-PCR检测OCT4在5种膀胱癌细胞株及人膀胱上皮永生化细胞株SV-HUC-1中的表达情况;同时收集46例患者膀胱癌根治手术切除的膀胱癌组织标本,应用免疫组织化学方法检测OCT4蛋白的表达。结果 OCT4在人类膀胱癌细胞株RT-4、Tcc-Sup、KK47、T24、5637中均有表达,而在人膀胱永生化细胞株中无表达。OCT4在膀胱癌组织中的表达率为76.1%,在正常膀胱组织中无表达。其异性染色定位于肿瘤细胞核内;膀胱癌组织OCT4蛋白阳性表达率显著高于正常组织(P<0.05);膀胱癌组织中的OCT4蛋白的表达与肿瘤病理分级呈正相关(P<0.05),与膀胱癌的浸润深度无相关性(P>0.05);与肿瘤转移呈正相关(P<0.05);与年龄、性别、TNM分期无明显相关性。OCT4阳性膀胱癌患者及阴性患者的3年总生存率分别为42.2%和76.7%,无转移生存率分别为35.4%和59.2%,结果均有统计学意义。结论膀胱癌组织中OCT4蛋白的表达与肿瘤分化程度及转移相关,对膀胱癌的早期诊断和预后分析有显著意义。

Expression of OCT4 protein in bladder cancer and its clinicopathological implications

Objective To study the expression of OCT4 protein in bladder cancer and its correlation to the clinicopathologic features and prognosis of bladder cancer.Methods OCT4 mRNA and protein expression was detected in 5 bladder cancer cell lines(RT-4,Tcc-Sup,KK47,T24,and 5637) and 1 normal bladder cell lines by real-time PCR and Western blotting,respectively.Immunohistochemical analysis was used to detect the expression of OCT4 protein in 46 bladder cancer samples.Results All the 5 bladder cancer cell lines expressed detectable levels of OCT4 mRNA and proteins,whereas the normal bladder cell line SV-HUC-1 was negative for OCT4 expression.The clinical bladder cancer tissues showed a high positivity rate of OCT4 expression(76.1%),which was not detected in normal bladder tissues.Specific OCT-4 signals were localized mainly in the nuclei of the cancer cells.The expression rate of OCT4 protein was significantly higher in bladder cancer tissue than in normal bladder epithelium(P<0.05),and showed a positive correlation to the grade of tumor differentiation and metastasis(P<0.05) but not to the patients’ age,gender or TNM stage.Conclusion OCT4 protein expression is associated with tumor differentiation and metastasis in bladder cancer and may play an important role in the early diagnosis and prognostic evaluation of bladder cancer.