PARP1 and breast carcinoma: The breast-cancer-associated genes 1 and 2 (BRCA1 and BRCA2) mediate HR, a DNA repair mechanism for double-strand DNA breaks [5,6], and the loss of either one of these genes coupled with the inactivation of PARP1 results in synthetic lethality and cell death as cells with mutations in BRCA1 or BRCA2 are unable to effectively perform HR [7,8].