These include a low tumour mutation burden of around 2 mutations per megabase5, low expression of programmed death-ligand 1 (PD-L1)6, loss of human leucocyte antigen (HLA)7, frequent 9p21 deletion5,8, a markedly immunosuppressive tumour microenvironment9,10, and epithelial-mesenchymal transition (EMT)11. Here, CD274 is linked to neoplasm.