title: [Hepatitis C virus strain JFH1 down-regulates expression of growth arrest and DNA damage-inducible gene 45a in human hepatoma Huh7.5.1 cells].
abstract: OBJECTIVE
  To investigate the effect of hepatitis C virus (HCV) strain JFH1 on expression of the human gene, growth arrest and DNA damage-inducible gene 45 alpha (GADD45a), in infected hepatoma cells.
  
  
  METHODS
  HCV JFH1 RNA-containing supernatants were used to infect the human hepatoma cell line, Huh7.5.1; infection was confirmed by Western blot detection of the HCV-encoded non-structural 5A (NS5A) protein and core protein. Infection-induced changes in GADD45a mRNA and protein expressions were measured by real time PCR using SYBR Green and Western blotting, respectively. Significance of differences between the levels detected in JFH1-infected or uninfected Huh7.5.1 cells was analyzed by single factor analysis of variance testing.
  
  
  RESULTS
  The HCV infection system was successfully established, as evidenced by expression of NS5A protein and core protein. The GADD45a mRNA and protein levels were significantly down-regulated in JFH1-infected Huh7.5.1 cells, by 0.57+/-0.09 and 0.28+/-0.03, respectively, as compared to levels in uninfected Huh7.5.1 cells (F values were 75.407 and 560.04, respectively; P less than 0.01).
  
  
  CONCLUSIONS
  HCV inhibits the mRNA transcription and protein expression of host GADD45a, which may contribute to the pathogenesis of hepatocellular carcinoma caused by HCV infection.
authors.affiliation: Department of Infectious Diseases, Second Xiangya Hospital, Central South University, Changsha, China.
authors.forename: Du
authors.initials: D
authors.lastname: Cheng
authors.forename: Yong-fang
authors.initials: YF
authors.lastname: Jiang
authors.forename: Xin-qiang
authors.initials: XQ
authors.lastname: Xiao
authors.forename: Guo-zhong
authors.initials: GZ
authors.lastname: Gong
mesh_terms: D045744:Cell Line, Tumor; D004249:DNA Damage; D016174:Hepacivirus / Q000145:classification; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D014158:Transcription, Genetic; D000097642:GADD45 Proteins
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D000097642:GADD45 Proteins