PDCD1 and cancer: To claim that they are exhaustion marker genes in the pan-cancer setting, we evaluated the expression patterns of canonical T cell exhaustion (Tex) marker genes, including LAG3, PDCD1, TIGIT, HAVCR2, CXCL13 and LAYN, alongside T cell effector function markers, such as IFNG, GZMB and PRF1 in pan-cancer, using TCGA data.