Circulating NK cells and tumour‐infiltrating NK cells isolated from noninvasive and invasive breast cancer patients show reduced expression of the significant effector factors, such as IFN‐γ, CD107a, granzyme B, Fas ligand, tumour necrosis factor–related apoptosis‐inducing ligand (TRAIL), and perforin.96 The gene discussed is IFNG; the disease is neoplasm.