Yang Sheng-Li, Zeng Cui, Fang Xiefan, He Qian-Jin, Liu Li-Ping, Bao Shi-Yun, Pan Xiaoli, Xiong Zhi-Fan
Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, P.R. China.
Division of Gastroenterology, Liyuan Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430077, P.R. China.
Oncol Lett. 2018 Apr;15(4):5264-5270. doi: 10.3892/ol.2018.7955. Epub 2018 Feb 5.
Golgi Protein 73 (GP73) is a newly identified diagnostic and prognostic marker for liver cancer. GP73 is highly expressed in liver cancer tissues, however, the mechanism of its overexpression in tumors remains unknown. In the present study, the effect of hepatitis B virus (HBV) on GP73 expression was investigated in HepG2 cells, which are negative for HBV, and in HepG2.2.12 cells, which are integrated with HBV, using reverse transcription-quantitative polymerase chain reaction and western blot analysis. In addition, the cells were transfected with plasmid constructs overexpressing hepatitis B virus protein X (HBx), hypoxia-inducible factor (HIF)-1α, or HIF-2α in order to examine their roles in GP73 expression. The results demonstrated that HBV upregulated the expression of GP73 and HIF-2α in liver cancer cells. HIF-2α induced the expression of GP73 in HepG2 cells and was positively correlated with GP73 expression in liver cancer tissues. By contrast, HBx and HIF-1α did not induce GP73 expression in liver cancer cells. In summary, HBV may upregulate the expression of GP73 by activating the HIF-2α signaling pathway. The present results may illuminate the mechanism by which GP73 is overexpressed in liver cancer tissues.
高尔基体蛋白73(GP73)是一种新发现的肝癌诊断和预后标志物。GP73在肝癌组织中高表达,然而,其在肿瘤中过表达的机制尚不清楚。在本研究中,利用逆转录定量聚合酶链反应和蛋白质印迹分析,在乙肝病毒(HBV)阴性的HepG2细胞和整合有HBV的HepG2.2.12细胞中研究了HBV对GP73表达的影响。此外,用过量表达乙肝病毒X蛋白(HBx)、缺氧诱导因子(HIF)-1α或HIF-2α的质粒构建体转染细胞,以研究它们在GP73表达中的作用。结果表明,HBV上调了肝癌细胞中GP73和HIF-2α的表达。HIF-2α诱导HepG2细胞中GP73的表达,且与肝癌组织中GP73的表达呈正相关。相比之下,HBx和HIF-1α未诱导肝癌细胞中GP73的表达。总之,HBV可能通过激活HIF-2α信号通路上调GP73的表达。本研究结果可能阐明了GP73在肝癌组织中过表达的机制。