CD274 and ovarian carcinoma: Antibodies to PD-1 (nivolumab and pembrolizumab) and PD-L1 (durvalumab, avelumab, atezolizumab) have been developed for cancer immunotherapy, and have been tested as monotherapies and combined in clinical trials with ipilimumab [48,295], including for epithelial ovarian cancer [8].