In a recent study by Di Pilato et al., an increase in IFN-γ levels favored the expression of PD-1 on effector T-cells and synthesis of PD-L1 by cancer cells and macrophages [29], thereby turning off CD4+CD25− conventional effector T-cells, reactivating an immune escape mechanism and increasing macrophage activation [30]. This evidence concerns the gene CD274 and cancer.