PRF1 and hepatocellular carcinoma: Notably, combination treatment induced a higher polyfunctionality of CAR-T cells with increased cytokine composition of co-secreting IFN-γ, granzyme B, and perforin, etc., at single-cell level in vitro compared with each treatment (Supplemental Figure 7, C and D) and enabled improvement of antitumor activity of CAR-T cells in NOD scid gamma (NSG) mice bearing HCC-1806 tumors (Figure 4, T and U).