CD274 and cancer: Once stimulated, TAMs can influence the surrounding cells through secretion of growth factors, proteolytic enzymes, cytokines, and inflammatory substrates that further contribute to different tumor promoting mechanisms: immunosuppression (PD-L1, PD-L2, CD80, CD86, IL-10, TGF-β, Arginase-1, prostaglandins), cancer stem cells (TGF-β1, IL-10, MFG-E8, IL-6), epithelial to mesenchymal transition (EMT) (TLR4/IL-10 signaling, TGF-β) (11).