Furthermore, considering that anti-CTLA-4 therapeutic efficacy can heavily depend on depletion of intra-tumoral CTLA-4+ Treg by ADCC (145), it is possible that anti-PD-1/PD-L1 therapy efficacy could similarly depend on the depletion of either PD-1+ and/or PD-L1+ tumor-infiltrating Treg, at least in those patients in which these types of inhibitory cells dominate suppression of anti-tumor response. The gene discussed is PDCD1; the disease is neoplasm.