PDCD1 and ovarian cancer: Bilska et al. (2020) determined the proinflammatory nature of the ovarian cancer microenvironment with high levels of IL-17A in the peritoneal fluid and a high percentage of Th17 infiltration and suggested that Th17 cells/IL-17A may serve an advantageous role in ovarian cancer immunity. A number of studies have proved that the PD-1/PD-L1 cascade, B cell and T cell receptor signaling axes, and TNF signaling cascades were associated with ovarian cancer immunity (Ghisoni et al., 2019; Gupta et al., 2019; Josephs et al., 2017).