CDK5在肝细胞癌中的异常表达

Abnormal expression of cyclin-dependent kinase 5 in hepatocellular carcinoma

目的:研究周期素依赖性激酶5(cyclin-dependent kinase5,CDK5)在肝细胞癌(hepatocellular carcinoma,HCC)发生发展中的异常表达.方法:应用反转录聚合酶链式反应(RT-PCR)检测CDK5mRNA的表达水平;免疫组织化学技术检测CDK5蛋白在正常肝组织、肝硬化和HCC组织中的表达;分析CDK5与临床病理学特征的关系.结果:CDK5mRNA在HCC中呈上调表达,阳性表达率在正常肝组织、肝硬化和HCC组织中分别为35.3%、64.3%、89.7%;正常肝组织与HCC组织有显著差异(P<0.05),肝硬化组织与HCC组织也有显著差异(P<0.01).CDK5蛋白在HCC中高表达,阳性表达率在人正常肝组织、肝硬化和HCC组织之间分别为29.4%,64.3%,89.7%,三组之间差异有统计学意义(χ2=58.095,P<0.01).HCC组织中CDK5蛋白表达强度与肿瘤的病理学分级显著相关(χ2=19.330,P<0.01).结论:CDK5在HCC中上调表达,他的异常表达在HCC的发生发展过程中发挥重要的作用,且与肿瘤的分化程度相关.

AIM：To investigate the abnormal expression of cyclin-dependent kinase 5 （CDK 5） in hepatocellular carcinoma （HCC）.METHODS：The expression of CDK5 mRNA and protein in normal liver tissue,liver cirrhosis and HCC was measured by reverse transcription-polymerase chain reaction （RT-PCR） and immunohistochemistry,respectively.The relationship between CDK5 expression and the clinicopathological characteristics of HCC was then analyzed.RESULTS：The expression of CDK5 mRNAwas up-regulated in HCC when compared with noncancerous liver tissue.The positive rates of CDK5 mRNA expression were 29.4%,64.3% and 89.7% in normal liver tissue,liver cirrhosis and HCC,respectively.Significant differences were noted in the positive rates of CDK5 mRNA expression between normal liver tissue and HCC （P〈0.05） and between liver cirrhosis and HCC （P〈0.01）.Immunohistochemistry analysis also revealed up-regulated expression of CDK5 in HCC compared with noncancerous liver tissue.The positive rates of CDK5 protein were 29.4%,64.3% and 89.7% in normal liver tissue,liver cirrhosis and HCC,respectively.Significant differences were noted in the positive rates of CDK5 protein expression among the three groups （χ 2=58.095,all P〈0.01）.The overexpression of CDK5 is significantly correlated with the pathological grade of HCC （χ ^2=19.330,P〈0.01）.CONCLUSION：CDK5 is up-regulated in HCC compared with noncancerous liver tissue.CDK5 plays an important role in the carcinogenesis of HCC.CDK5 overexpression may be related to tumor differentiation in HCC.