PARP inhibitors. PARP inhibitors (PARPis), which inhibit PARP1 as well as other PARP family members153, are FDA approved for high-grade serous ovarian cancer, germlineBRCA1/2-mutated breast cancer, andBRCA1/2-mutated castration-resistant prostate cancer154–158. Here, PARP1 is linked to breast carcinoma.