PARP1 and cancer: Irrespective of BRCA mutation status, PARP inhibitors are effective against all tumors, although therapeutic efficacy is higher in patients with BRCA mutations/HRD, as observed in clinical trials.[12] Recently, survival benefit was observed in patients with epithelial ovarian carcinoma treated with PARPi, veliparib, and paclitaxel and carboplatin, followed by veliparib compared with chemotherapy alone in the Phase III VELIA trial.[53] Hence, there is a need of understanding the molecular mechanism of PARP inhibitors to enhance its efficacy against HRP cancers through combination therapy.