CD274 and neoplasm: In the TME, the establishment of a highly immunosuppressive microenvironment by tumor‐associated macrophages (TAMs) is pivotal for tumor progression, and is achieved through the release of mediators with immunosuppressive or antiinflammatory activity (such as IL‐10 or TGF‐β), the expression of immune checkpoints (such as programmed death ligand 1, PD‐L1) or the recruitment of other immunosuppressive cells (including T regulatory cells, Tregs),3 thus providing a protective niche to support tumor growth.