KLRC1 and colorectal carcinoma: Regarding the action of inhibitory receptors linked with NK cell dysfunction other than KIR, in several patients affected by gastrointestinal cancers, including CRC, the expression of the immune checkpoints NKG2A and TIGIT is increased on tumor-infiltrating NK cells and is correlated with impaired NK cell cytotoxicity, advanced disease stage, and poor survival [133,134,139].