CD274 and ovarian neoplasm: Both immunosuppressive systems (PD‐L1/PD‐1 and Treg infiltration) have previously been shown to predict unfavorable outcome in OC.25, 27, 38 Moreover, RIG‐I levels in ovarian tumors were quite strongly associated with ADAR1 expression, an immune‐silencing factor that may reduce the sensitivity to checkpoint inhibition.33, 39, 40