肝细胞癌中雄激素受体与乙型肝炎病毒X蛋白表达的相关性及临床意义

Correlation between androgen receptor expression and hepatitis B virus X protein and its clinicalsignificance in hepatocellular carcinoma

目的探讨肝细胞癌（HCC）组织中雄激素受体（AR）与乙型肝炎病毒X蛋白（HBx）表达的相关性及其临床意义。方法荧光定量PCR检测AR和HBxmRNA的表达水平，Westernblot和免疫组化检测AR和HBx蛋白的表达情况，甲基化特异性聚合酶链反应检测AR启动子的甲基化状态。结果乙型肝炎病毒（HBV）相关HCC癌旁组织中ARmRNA的相对表达水平（0．17）高于癌组织（0．09，P〈0．01），而HBV阴性HCC癌旁组织中ARmRNA的相对表达水平（0．06）与癌组织（0．07）差异无统计学意义（P〉0．05）。HBV相关HCC癌和癌旁组织中ARmRNA的相对表达水平均高于HBV阴性HCC组（均P〈0．05）。HBV相关HCC癌旁组织AR蛋白的表达水平（0．35）高于癌组织（0．18，P〈0．05）。HBV阴性HCC癌和癌旁组织AR蛋白的表达水平分别为0．17和0．21，差异无统计学意义（P〉0．05）。HBV相关HCC癌旁组织中AR蛋白的表达水平均高于HBV阴性HCC组和肝血管瘤组（0．14，均P〈0．05）。HBV相关HCC癌组织中AR蛋白的表达水平与HBV阴性HCC癌组织差异无统计学意义（P〉0．05）。HBV相关HCC癌旁组织中ARmRNA的相对表达水平与HBxmRNA呈正相关（P〈0．01），AR蛋白的相对表达水平与HBx蛋白呈正相关（P〈0．01）；HBV相关HCC癌组织中ARmRNA的相对表达水平与HBxmRNA呈正相关（P〈0．01），AR蛋白的相对表达水平与HBx也呈正相关（P〈0．05）。AR启动子甲基化组与非甲基化组问AR和HBx的mRNA和蛋白的表达水平差异均无统计学意义（均P〉0．05）。在HBV相关HCC中，癌旁组织ARmRNA和蛋白的相对表达水平与肿瘤的分化程度呈负相关（均P〈0．05），AR表达越高，肿瘤分化程度越差；I盯癌组织ARmRNA和蛋白的相埘表达水平与肿瘤的分化程度无关。结论HBx可能通过促进基凶的转录增加HCC中AR的表达水平，但AR基因的甲基化状态的改变可能不是其主要的调节机制。AR表达水平的增加也许是HBV相关性HCC癌变过程中的早期事件。癌旁组织中AR的表达与肿瘤的分化程度有关，有助于判断HCC患者的预后。AR在HBV相关HCC与HBV阴性HCC中发挥的作用可能并不相同。

Objective To investigate the expression of androgen receptor （AR） and hepatitis B virus X protein （HBx） in hepatocellular carcinoma （HCC）, and analyze the relationship between AR and HBx expressions. Methods Tumor tissues and peritumoral tissues of 83 HBV-associated HCC cases were investigated in this study. Fourteen cases of HBV-negative HCC and 13 cases of hemangioma peritumoral tissues were considered as control. AR and HBx mRNA levels were determined by quantitative fluorescence real-time RT-PCR and their protein levels were assayed by Western blot. The expression of AR and HBx proteins in tissues were examined with EnVision immunohistoehemical staining. The methylation status of AR promoter was determined using methylation-specific PCR （MSP）. Results Both expression levels of ARmRNA and protein of the peritumoral tissues were significantly higher （0.17） than that of tumor tissues （0.09） in HBV-associated HCC （P 〈 0. O1 ）, but such a difference was not found in HBV-negative HCC （0.06 vs. O. 07, P 〉 O. 05 ）. The level of AR expression in peritumoral tissues was associated with tumor differentiation in HBV-associated HCC. AR mRNA and protein levels of peritumoral tissues in HBV- associated HCC were significantly higher than that in HBV-negative HCC and hemangioma （ all P 〈 O. 05 ）. In the tumor tissues, HBV-associated HCC had significantly higher AR expression than HBV-negative HCC at mRNA level （ P 〈 O. 05） , but not at protein level. Spearman rank correlation analysis showed that the AR mRNA or AR protein levels were positively correlated with HBx in both tumor and peritumoral tissues in HBV-associated HCC, but the expressions of AR and HBx were not associated with AR promoter methylation status. The relative expression levels of AR mRNA and protein in the HBV-associated peritumoral tissues were negatively correlated with tumor differentiation （ r = - O. 213, P 〈 0.05 ; r = - O. 313, P 〈 0.05 ）, the higher the AR expression, the poorer differentiation. But this correlation of AR mRNA and protein was not shown in the hepatocellular carcinoma tissues. Conclusions HBx may enhance AR expression in HBV- associated HCC, but AR promoter demethylation maybe not been involved in its main mechanism. An increased AR expression is probably an early event during the development and progression of HBV- associated HCC, and AR expression in the peritumoral tissue is correlated with HBV-associated HCC differentiation. AR may play different roles in HBV-associated HCC and HBV-negative HCC.