While IL-6 (and hyperIL-6) induce the differential regulation of thousands of mRNAs in HepG2 and HuH-7 hepatoma cell lines, only selected miRNAs change their expression level significantly, including miR-21, miR-100, miR-145, miR-146b-5p. In contrast, we have observed previously that IFN-g has a profound effect on the miRNome of melanoma cells (Schmitt, Cell Comm. Sign. 2012). Therefore we investigate whether IL-6-type cytokines may have generally weaker effects on the miRNome compared to interferons and/or whether our observation is due to cell type-specific differences.
To extend our in vitro findings, we analyse and correlate the expression levels of miRNAs and inflammatory cytokines in patients with HCC and advanced nonalcoholic steatohepatitis (NASH), the latter being at high risk to develop HCC. Bio-Plex cytokine immunoassays revealed that the serum level of IL-6 and HGF is higher in HCC patients than in healthy controls and NASH patients. Our work may contribute to the identification of novel biomarkers for the progression of chronic liver diseases.