As IFN-γ-mediated upregulation of PD-L1 has been shown to be a mechanism of adaptive immune tolerance39,69, it remains possible that PD-1/PD-L1 blockade could potentially enhance the antitumor activity of a-CTLA4-TGFβRII over a more extended treatment period or in other tumor models. This evidence concerns the gene IFNG and neoplasm.