CD274 and melanoma: Another study in a mouse model of melanoma showed that tumor-associated lymphatic endothelial cells (LECs) express Programmed death-ligand 1 (PD-L1), an immune checkpoint inhibitor, and in response to IFNγ production by antigen-specific CD8+ T cells, tumor-associated LECs increased PD-L1 expression limiting local effector CD8+ T cell accumulation (80).