CTLA4 and cancer: For instance, single anti-PD-1 treatment resulted in expansion of exhausted CTL (PD-1 + , LAG-3 + , TIGIT + ) but failed to induce tumor control in a HCC mouse model.175Furthermore, CTLA-4 blockade increases activation of CTL in the lymph node and therefore the probability of cancer antigen–specific CTL infiltrating the TME34(Fig. 1).