USP18 and hepatocellular carcinoma: To dissect mechanisms that regulate dose‐dependent sensitization of IFNα signal transduction in hepatoma cell lines, we employed the mathematical model to simulate in Huh7.5 and HepG2‐hNTCP cell lines the amounts of STAT1, STAT2, IRF9, and USP18 protein for untreated cells and for cells prestimulated with 1.2 pM or 608 pM Roferon for 24 h (Fig 6A).