In tumour CD8+ T cells, treatment with anti-PD-L1 sustained expression of the gene program associated with exhaustion, characterized by the transcriptional regulators Tox, Nr4a2 and Id2 as well as the co-inhibitory receptors Pdcd1, Tigit, Lag3 and Havcr2. By contrast, treatment with anti-TIGIT antibodies drove a shift in tumour CD8+ T cells away from that program and towards one associated with memory state, with elevated expression of Tcf7, Klf2, Ccr7, Lef1, Il7r and Sell (Fig. 4c). This evidence concerns the gene LEF1 and neoplasm.