IFNG and neoplasm: However, CAR NK‐92 cells secrete abundant interferon‐γ (IFN‐γ) when they kill tumours, and IFN‐γ has been reported to not only generate a polarised immune response but also promote adaptive immune resistance by upregulation of programmed death ligand 1 (PD‐L1) on tumour cells in the TME.9