IFNG and neoplasm: It has been demonstrated that interferon γ (IFN-γ) induces over-expression of PD-L1 by tumor cells through manipulation of various signaling transducers such as protein kinase D isoform 2 (PKD2), the Janus kinase (JAK)1, JAK2 and signal transducer and activator of transcription (STAT)1 pathway20.