As to the novel mechanistic explanation for the immune responses that lead to anti-PD-1 blockade-mediated tumor rejection, recent studies have shown that anti-PD-1 therapy leads to a dynamic expansion and proliferation of PD-1+ (exhausted-like) CD8 T cells in the PBMCs of melanoma and lung cancer patients29,30. This evidence concerns the gene PDCD1 and neoplasm.