PDCD1 and neoplasm: The immunotherapeutic modalities targeting single molecule or pathway remain insufficient to achieve durable clinical responses in patients with advanced OC [35], which is simply exemplified by the fact that single treatment with even “brilliant star” antibodies targeting immune checkpoint PD-1 did not produce an optimal antitumor response in OC patients [17], accordingly, studies from us and other groups found that single treatment with α-PD-1 mAb showed little antitumor effect in mice bearing ID8 tumor [25–29].