PD-L1 expression can be induced by both type I and type II interferons, TNF-α, and vascular endothelial growth factor (VEGF).60 Type I interferons, IFN-α and IFN-β stimulate PD-L1 expression.61 In prostate cancer and kidney cancer, TNF-α upregulates PD-L1 expression by activating NF-κB pathway.62,63 Type II interferon IFN-γ binds to IFNGR and triggers JAK-STAT1-IRF1 to modulate PD-L1 expression. This evidence concerns the gene TNF and kidney cancer.