The reinvigorate dysfunctional or ‘exhausted’ cytotoxic CD8+ T cells can be enabled to attack the cancer cells and counter the immunosuppression by anticancer immunotherapy with immune checkpoint inhibitors (ICIs) (Zou, Wolchok & Chen, 2016; Pardoll, 2012); anti-PD-L1 monoclonal antibodies (mAbs), anti-PD-1 and anti-CTLA-4, have shown remarkable clinical efficacy across a range of different cancers, with advanced-stage disease patients (Topalian et al., 2012) (Taneja, 2012). The gene discussed is PDCD1; the disease is cancer.