CTLA4 and neoplasm: Profiling of tumor-infiltrating CD8 T cells in NSCLC patients (n = 32) revealed increased expression of immune inhibitory molecules PD-1, TIM-3, CTLA-4, LAG-3, and BTLA correlating with T cell dysfunction and tumor progression (Thommen et al. 2015), and expression of these immune inhibitory checkpoints may exert an immunosuppressive state despite anti-PD-1 treatment.