KLRK1 and neoplasm: To investigate whether the enhanced expression levels of NKG2DL on the tumor cell surface are associated with their improved recognition and cytotoxicity by NKG2D CAR-T cells, we measured the cytotoxicity of NKG2D CAR-T cells against the tumor cells after co-culture with a subtoxic concentration of VPA or the untreated glioblastoma cancer cells.