Cancer immunotherapy with Immune checkpoint blockade (ICB), such as the antibodies against programmed cell death protein-1 (PD-1) and programmed death ligand-1 (PD-L1), has lately emerged as a revolutionary treatment strategy for various types of cancer [3–7], including melanoma and lung cancer, which exhibits a thrilling response rate of 50% [8, 9]. The gene discussed is PDCD1; the disease is lung cancer.