STAT1 and cancer: In general, the eIF4F complex, a eukaryotic translation initiation complex, regulates the translation of mRNA encoding STAT1 (one of the main transcriptional regulators of PD-L1) by binding to the RNA sequence in the 5’-UTR of STAT1, thereby modulating the expression of IFN-γ-induced PD-L1 on cancer cells [272].Subsequently, post-translational modifications, including phosphorylation, ubiquitination, glycosylation, and palmitoylation regulate the expression of PD-L1 protein by affecting activity, stability, and membrane expression in cancer cells [273, 274] (Fig. 7).