PARP1 and ovarian cancer: Despite the lack of clinical evidence, two small cohort studies reported that PARG negative areas accounting for 10% or more of the overall tumor mass which have been found in a significant proportion of tumors present in females suffering from triple-negative breast cancers (76.8%) or ovarian cancer (78.4%), for which PARP inhibitors can be used as a therapeutic approach for both (Gogola et al., 2018).