KLRK1 and neoplasm: NK cells play a pivotal role in innate immunity, targeting virus-infected and malignant cells through stress-induced ligands (e.g., NKG2D ligands: MICA, MICB, ULBPs) or via the'missing-self'mechanism, which identifies the absence of HLA class I molecules, a common tumour-immune evasion strategy​ [253].