Hepatitis C virus strain JFH1 down-regulates expression of growth arrest and DNA damage-inducible gene 45a in human hepatoma Huh7.5.1 cells / 中华肝脏病杂志

ABSTRACT

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSION</b>HCV inhibits the mRNA transcription and protein expression of host GADD45a, which may contribute to the pathogenesis of hepatocellular carcinoma caused by HCV infection.</p>