Similarly, targeting the PD-1 ligand (PD-L1) with the monoclonal antibody atezolizumab has proved efficacious with tolerable side effects in a phase 1 trial of metastatic melanoma, non-small cell lung cancer (NSCLC) and renal cell cancer, in patients with tumours expressing high total and high CD8+ T cell levels of PD-L1 [87]. Here, CD274 is linked to metastatic melanoma.