KLRK1 and hepatocellular carcinoma: In Figs. 2A-2C, NKG2D and NKp30 were similarly expressed in NK-92 cells cocultured with HCC and apigenin-treated HCC cells (NKG2D+; non-treated 71.01%, treated 68.09%; NKp30+; non-treated 64.27%, treated 67.50%; ns); however, the expression of NK44 on NK-92 was significantly lower in a coculture of HCC treated with apigenin (NKp44+; non-treated 20.72%, treated 17.41%, *p < 0.05).