CD8A and neoplasm: Both melanoma cells and ECs also express endothelin B receptor (ETBR) and its ligand endothelin-1,41 which acts through nitric oxide to inhibit T-cell adhesion onto the endothelium.42 Apart from that, the tumour endothelium also specifically expresses FasL that can directly kill activated CD8+ T-cells, thereby resulting in decreased CD8+ T-cell infiltration in multiple solid tumours.43