PARP1 and breast cancer: PARPi with the capacity for PARP1 and PARP2 (PARP1/2) DNA trapping, have achieved widespread success as a target therapeutics for a variety of cancers, as ovarian cancer, breast cancer, pancreatic cancer and prostate cancer in particular, both in monotherapy and in combination with additional therapies such as anti-angiogenic agents or immune checkpoint inhibitors (Gong et al., 2020a).