CD274 and neoplasm: The other key factor in HCC angiogenesis, Ang-2, also exerts immunosuppressive activities via involvement in the recruitment of monocytes/macrophages in the tumor microenvironment (TME) and induction of the expression of the immune checkpoint programmed death-ligand 1 (PD-L1) on the surface of tumor-associated macrophages (TAMs) and may thus also contribute to the resistance to ICI therapy.