NK cell activator Poly (I:C) promotes HCC in HBs-Tg mice. Poly (I:C) induces liver inflammation and liver cell damage in HBs-Tg mice. The increase of hepatocyte EMT depends on the presence of NK cells in HBs-Tg mice. IFN-γ derived from NK cells plays a key role in the development of HCC in HBs-Tg mice. This evidence concerns the gene IFNG and hepatocellular carcinoma.