KLRK1 and myeloid leukemia: To determine whether or not the rs1049174 variants correlated with NKG2D-mediated cytotoxicity, NK cells derived from healthy individuals were tested for cytotoxicity against the myeloid leukemia OUN-1 cell line with or without VPA treatment, an inducer of NKG2D-Ls12, 14 (Fig. 2A).