GAS5 and hepatocellular carcinoma: Additionally, tumor cells may promote GAS5 downregulation to evade immune elimination, as knockdown of GAS5 impairs IFN-γ and TNF-α secretion and the cytotoxic activity of NK cells against hepatocellular carcinoma and MGC-803 cells, while its overexpression favors tumor rejection in a xenograft mouse model [157].