Our findings revealed that apigenin strongly suppressed the IFN-γ-induced upregulation of PD-L1 via the inhibition of STAT1 phosphorylation on tyrosine 701, thus providing a mechanistic explanation for its impact on PD-L1 expression in melanoma cells, which was consistent with previous observations of apigenin effect in breast cancer [40]. This evidence concerns the gene CD274 and breast cancer.