In addition, some cancer cells also express PD-L1,[12] and approximately 60% of NSCLCs are PD-L1–positive.[13] Blockade of the PD-1 pathway is believed to increase the anti-tumor immune function of T-cells, enhance natural killer cell activity, and promote antibody production in PD-1–positive B cells.[7,9]. The gene discussed is PDCD1; the disease is cancer.