CD274 and neoplasm: In particular, MAFs exposed to tumor-derived IL-1 α/β induce T cell suppression by rapidly upregulating the expression of PD-1 ligands (PD-L1 and PD-L2) and COX-2 [180], which are well-known molecules exerting powerful suppressive effects on T cells, in multiple cancer types (Figure 3) [181,182].