Similar studies combining computational, molecular, and functional systems aimed to precisely define a tumor specific CD8+ T-cell exhaustion gene signature in order to discover potential new targets for immunotherapies.145,247 A recent study identified a subpopulation of “progenitor exhausted” CD8+ T cells, carrying a unique genetic and epigenetic signature and being able to respond better to anti-PD-1 therapy. This evidence concerns the gene PDCD1 and neoplasm.