title: The co-localization of HBx and COXIII upregulates COX-2 promoting HepG2 cell growth.
abstract: HBx is a multifunctional regulator that interacts with host factors to contribute to the development of hepatocellular carcinoma. In this study, to explore the co-localization of HBx and COXIII in HepG2 cells and to investigate the molecular mechanism of HBx in HepG2 cell growth promotion, we first constructed a HepG2 cell line stably expressing the HBx gene in vitro by lentivirus vectors. In addition, we found that HBx co-localized with the inner mitochondrial protein, COXIII, in HepG2 cells by confocal laser scanning microscopy. It led to changes of mitochondrial biogenesis and morphology, including upregulation of COXIII protein expression, increased cytochrome c oxidase activity and higher mitochondrial membrane potential. The upregulation of COX-2 caused by HBx through generation of mitochondrial reactive oxygen species promoted cell growth. Thus, we conclude that co-localization of HBx and COXIII leads to upregulation of COX-2 that promotes HepG2 cell growth. Such a mechanism provides deeper insights into the molecular mechanism of HBV-associated hepatocellular carcinoma.
authors.affiliation: Graduate School, Fujian Medical University, Fuzhou, Fujian 350001, P.R. China.
authors.forename: Bi-Yun
authors.initials: BY
authors.lastname: Zheng
authors.affiliation: Department of Gastroenterology, Union Hospital of Fujian Medical University, Fuzhou, Fujian 350001, P.R. China.
authors.forename: Xue-Fen
authors.initials: XF
authors.lastname: Fang
authors.affiliation: Department of Infection, Union Hospital of Fujian Medical University, Fuzhou, Fujian 350001, P.R. China.
authors.forename: Lai-Yu
authors.initials: LY
authors.lastname: Zou
authors.affiliation: Department of Gastroenterology, Union Hospital of Fujian Medical University, Fuzhou, Fujian 350001, P.R. China.
authors.forename: Yue-Hong
authors.initials: YH
authors.lastname: Huang
authors.affiliation: Department of Gastroenterology, Union Hospital of Fujian Medical University, Fuzhou, Fujian 350001, P.R. China.
authors.forename: Zhi-Xin
authors.initials: ZX
authors.lastname: Chen
authors.affiliation: Department of Gastroenterology, Union Hospital of Fujian Medical University, Fuzhou, Fujian 350001, P.R. China.
authors.forename: Dan
authors.initials: D
authors.lastname: Li
authors.affiliation: Laboratory of Electron Microscopy, Fujian Medical University, Fuzhou, Fujian 350001, P.R. China.
authors.forename: Lin-Ying
authors.initials: LY
authors.lastname: Zhou
authors.affiliation: Department of Gastroenterology, The Third Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350108, P.R. China.
authors.forename: Hao
authors.initials: H
authors.lastname: Chen
authors.affiliation: Department of Gastroenterology, Union Hospital of Fujian Medical University, Fuzhou, Fujian 350001, P.R. China.
authors.forename: Xiao-Zhong
authors.initials: XZ
authors.lastname: Wang
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000378:metabolism / Q000473:pathology* / Q000821:virology; D049109:Cell Proliferation; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D057809:HEK293 Cells; D056945:Hep G2 Cells; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000821:virology; D018613:Microscopy, Confocal; D008928:Mitochondria / Q000378:metabolism*; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D015534:Trans-Activators / Q000378:metabolism*; D054334:Viral Regulatory and Accessory Proteins
chemical_list: D017382:Reactive Oxygen Species; D015534:Trans-Activators; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; C466421:cyclooxygenase-3