CD274 and hepatocellular carcinoma: In the coculture system of PBMCs and HCC cells, knockdown of TIP60 or treatment with anti-PD-L1 enhanced T lymphocyte activation, as evidenced by increasing CD8+ T cell percentage and IFN-γ level, which was enforced by combination of TIP60 knockdown and PD-L1 antibody (Fig. 1D, E).