In addition to the effector T cell tumor interface, antitumor immunity can be induced by blockade of the PD-L1:PD-1 pathway on dendritic cells, resulting in increased CD8-positive T cell infiltration of the tumor and suppression of the inhibitory ability of Tregs either directly or indirectly through augmentation of CTL proliferation (41, 42). This evidence concerns the gene PDCD1 and neoplasm.