Olaparib, rucaparib, niraparib, veliparib (ABT-888), pamiparib, simmiparib, and talazoparib can be applied for the treatment of breast and ovarian cancers showing BRCA1/2 mutations, in which lower-fidelity non-homologous end-joining (NHEJ) occurs, resulting in chromosomal aberration and in cell death [64,68]. This evidence concerns the gene BRCA1 and ovarian cancer.