title: The molecular and pathophysiological implications of hepatitis B X antigen in chronic hepatitis B virus infection.
abstract: Hepatitis B virus is considered one of the most significant environmental carcinogens in humans. Because the mechanisms of HBV replication and the development of hepatocellular carcinoma (HCC) are partially known, HBV-associated pathogenesis remains a challenge to increase its understanding. Evidence suggests that the regulatory protein hepatitis B virus X (HBx) mediates the establishment and maintenance of the chronic carrier state. HBx is a multifunctional and potentially oncogenic protein that is conserved among mammalian hepadnaviruses; it is produced very early after infection and throughout the chronic phase. HBx exerts its effects by interacting with cellular proteins and activating various signaling pathways. HBx stimulates the transcription of genes that regulate cell growth, apoptosis, and DNA repair. It also interacts with proteasome subunits and affects mitochondrial stability. Moreover, HBx participates in processes that are associated with the progression of chronic liver disease, including angiogenesis and fibrosis. This review discusses the function of HBx in the life cycle of HBV and its contribution to the pathogenesis of HCC.
authors.affiliation: CIBERehd, ISCIII, Madrid, Spain; Servicio Digestivo, Hospital Universitario "La Princesa" and Instituto de Investigación Biomédica "La Princesa", Madrid, Spain.
authors.forename: Samuel
authors.initials: S
authors.lastname: Martin-Vilchez
authors.forename: Enrique
authors.initials: E
authors.lastname: Lara-Pezzi
authors.forename: Maria
authors.initials: M
authors.lastname: Trapero-Marugán
authors.forename: Ricardo
authors.initials: R
authors.lastname: Moreno-Otero
authors.forename: Paloma
authors.initials: P
authors.lastname: Sanz-Cameno
mesh_terms: D005355:Fibrosis; D006515:Hepatitis B virus / Q000254:growth & development / Q000502:physiology*; D019694:Hepatitis B, Chronic / Q000473:pathology* / Q000821:virology*; D054884:Host-Pathogen Interactions; D006801:Humans; D009389:Neovascularization, Pathologic; D015398:Signal Transduction; D015534:Trans-Activators / Q000378:metabolism*; D054334:Viral Regulatory and Accessory Proteins; D014779:Virus Replication
chemical_list: D015534:Trans-Activators; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein