CD274 and neoplasm: As has been previously shown by our own work and others,24,33,34 OVs through their ability to induce local expression of type I interferons (IFNs) and type II IFN-γ result in the upregulation of inhibitory ligands (PD-L1 and PD-L2) on tumor cells, thereby making “cold” tumors susceptible to ICB.