As an inflammatory factor in tumor microenvironment, IFN-γ is one of the main factors inducing overexpression of PD-L1 in tumor cells and resulted in immune escape [27, 28].The underlying mechanism is that IFN-γ induces PD-L1 expression by activating downstream JAK-STAT signaling pathway [29, 30]. This evidence concerns the gene IFNG and neoplasm.