In multiple mouse models, NK cells played a key role in the efficacy of PD-1-PD-L1 blockade in both effector T cell-resistant (i.e., MHC-Ilo) tumors, where the effects of the therapies were NK cell-dependent, and T cell-sensitive tumors (MHC-Ihi), where the depletion of either CD8+ T cells or NK cells led to similar increases in tumor growth suggesting that also in T cell sensitive tumors, NK cells play a role in the efficacy of PD-1-PD-L1 blockade [75]. The gene discussed is PDCD1; the disease is neoplasm.