KLRK1 and cancer: It has been reported that NKG2D can be silenced by DNA methylation during the development of acute myeloid leukemia, and NKG2D ligand levels can be increased by using demethylating factors (e.g., azacitidine, decitabine) [173,174], which enhances the cytotoxic effect of the NK cells, resulting in the detection and lysis of cancer cells [172,175].