The molecular phenotype of tumour-infiltrating NK cells is closely linked to their function, and their surface molecules include activating and inhibitory receptors such as KIR (killer cell immunoglobulin-like receptor) and killer cell lectin like receptor C1 (KLRC1; also known as NKG2A) -mediated inhibitory signalling (94, 95). Here, KLRC1 is linked to neoplasm.