T-cell checkpoint blockade immunotherapies have recently emerged as revolutionary cancer treatments.1 Antibodies targeting the CTLA-4 receptor and the PD-1/PD-L1 axis reinvigorate T-cell-mediated cancer immunity, particularly in cancers with high mutation burden.2 In such malignancies, there is a high likelihood that neo-antigens are presented in complex with Human Leukocyte Antigen class I (HLA class I) at the surface of tumour cells and by antigen presenting cells. The gene discussed is CD274; the disease is cancer.