Considering the low response rate of immunotherapy, oncology researchers are now investigating anti-PD1/PD-L1 combination therapies, such as anti-PD-1/PD-L1 agents in combination with chemotherapy [36, 42–44], ipilimumab [29, 38], or bevacizumab [10], for the treatment of cancers. The gene discussed is PDCD1; the disease is cancer.