保罗样激酶1蛋白在肝细胞癌中的表达及临床意义

 目的 探讨肝细胞癌（HCC）组织及细胞系中保罗样激酶1（Plk1）蛋白的表达情况及其临床意义。方法 应用免疫组化SP法检测HCC组织67例、配对癌旁肝硬化组织27例及正常肝组织5例中Plk1蛋白的表达情况，并分析其与临床病理特征之间的关系。应用Western blot检测肝癌细胞系BCL-7402及HepG2细胞中Plk1蛋白的表达情况。结果 Plk1蛋白在HCC肝癌组织中的阳性表达率为76.1%(5167)，其中强阳性44.8%(3067)，在配对的癌旁肝硬化组织中均呈阳性表达，而5例正常肝组织中均无明显表达。高分化HCC肝癌中Plk1蛋白的表达明显高于中低分化HCC 肝癌(P0.01)；无包膜侵犯的HCC肝癌组织中Plk1蛋白的表达高于有包膜侵犯的HCC肝癌组织(P0.05)；Plk1的表达与患者年龄、肿瘤直径、肿瘤数目、淋巴结转移、肝外转移、及门静脉有无癌栓无关。肝癌细胞系BCL-7402及HepG2中均存在Plk1蛋白的过表达。结论 Plk1在HCC肝细胞癌中表达率较高，其阳性表达可能是HCC发生过程中一个关键的早期因素。

Expression and Clinical Significance of Plk1 Protein in Hepatocellular Carcinoma

Objective To investigate the expression and clinical significance of Polo-like kinase 1(Plk1) protein in hepatocellular carcinoma(HCC) tissues and the expression in hepatocellular carcinoma cell lines.Methods Immunohistochemical technique(SP) was used to detect the expression of the Plk1 protein in HCC tissues of 67 cases,27 cases of corresponding paracancerous cirrhosis tissues and 5 cases of normal tissues of liver.The relationship between clinical pathology characters and expression of the Plk1 protein were analyzed as well.Western blot was used to detect the expression of the Plk1 protein in hepatocellular carcinoma cell lines BCL-7402 and HepG2.Results The positive rate of Plk1 in HCC tissues was 76.1% and 44.8% of all carcinomas showed strong expression of Plk1.Twenty-seven cases of corresponding paracancerous cirrhosis tissues all showed positive expression.No significant Plk1 expression was observed in normal tissues of liver.The expression of Plk1 protein in well differentiated HCC tissues was markedly higher than that of poor differentiation tissues(P < 0.01).In addition,HCC tissues with peplos encroachment showed lower expression rates than others without peplos encroachment(P <0.05).There were no other significant correlations of Plk1 expression with either age,tumor diameter and quantity,lymphoid node metastasis,extrahepatic metastasis,or portal vein embolus could be established.Plk1 protein was found to be overexpressed in both hepatocellular carcinoma cell lines.Conclusion These results demonstrated a higher rate of Plk1-positivity in HCC which suggested involvement of Plk1 in tumorigenesis in this tumor entity and might be an important early event of this process.Therefore,targeted strategies focusing on Plk1 inhibition might represent a promising new therapy approach in hepatocellular carcinoma.