title: [Heat shock protein 90-mediated inhibition of hepatitis B virus replication in hepatic cells].
abstract: OBJECTIVE
  To evaluate the effect of heat shock protein 90 (HSP90) on hepatitis B virus (HBV) replication in hepatocytes and to investigate the related molecular mechanism.
  
  
  METHODS
  A eukaryotic plasmid expressing human HSP90 was constructed (designated as HA-HSP90). HepG2 cells were co-transfected with HA-HSP90 and the HBV replicative plasmid HBV1.3. Expression of the exogenous HSP90 was assessed by Western blotting. Expression of the HBV surface antigen (HBsAg) was determined by enzyme-linked immunosorbent assay, and HBV replicative intermediates were detected by Southern blotting. Small interfering (si)RNAs were designed against HSP90 and TBK1 and transfected into the HepG2 cells to further assess the effects of HSP90 and its underlying mechanism. HSP90-mediated effects on the expression of interleukins IL-1b and IL-6 and the interferon response gene IFIT1 were assessed by quantitating mRNA levels with real time RT-PCR.
  
  
  RESULTS
  The HA-HSP90 plasmid successfully expressed exogenous HSP90 protein in HepG2 cells. The exogenous HSP90 was able to inhibit HBV replication and HBsAg expression. IFIT1 expression was up-regulated after HA-HSP90 transfection, but neither IL-1b nor IL-6 were affected. The siRNA-mediated TBK1 down-regulation had no effect on the HSP90-inhibited HBV replication.
  
  
  CONCLUSIONS
  HSP90 can inhibit HBV replication and TBK1 is not involved in this process.
authors.affiliation: Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Hong-ping
authors.initials: HP
authors.lastname: Huang
authors.forename: Yuan
authors.initials: Y
authors.lastname: Yu
authors.forename: Shen-pei
authors.initials: SP
authors.lastname: Liu
authors.forename: Chun-yan
authors.initials: CY
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Chen
authors.forename: Yan
authors.initials: Y
authors.lastname: Yang
mesh_terms: D018841:HSP90 Heat-Shock Proteins / Q000235:genetics*; D056945:Hep G2 Cells; D006513:Hepatitis B e Antigens / Q000378:metabolism; D006515:Hepatitis B virus / Q000502:physiology*; D006801:Humans; D017346:Protein Serine-Threonine Kinases / Q000235:genetics; D014162:Transfection; D014779:Virus Replication
chemical_list: D018841:HSP90 Heat-Shock Proteins; D006513:Hepatitis B e Antigens; D017346:Protein Serine-Threonine Kinases