KLRK1 and colorectal carcinoma: Furthermore, the levels of activating receptors NKG2D, NKp30, and NKp46 positive NK cells in CRC patients was significantly lower compared to healthy controls (P < 0.01, P < 0.001, and P < 0.001, respectively); however, the level of inhibitory receptor KIR3DL1 positive NK cells was also significantly higher compared to the healthy controls (P < 0.001).