KLRK1 and hepatocellular carcinoma: Other research groups have also reported that peripheral blood NK cells activated by various cytokines [15], glypican 3 (GPC3)-specific CAR-engineered NK cells [16], NK cells expressing the NKG2D-CD3ζ-DAP10 receptor [17], and NK cells with TLR7/TLR8 agonists [18] are effective for HCC treatment [11, 19].