CD274 and ovarian carcinoma: As Trabectedin induces a profound growth inhibition and cell apoptosis in human ovarian cancer cell lines and our previous data showed that ID8 murine ovarian cancer cells do not express PD-1 and its ligand PD-L1 on their surface [25], we first evaluated the direct effect of Trabectedin and/or α-PD-1 mAb on the survival of ID8 cells in vitro.