BRCA1 and ovarian cancer: Accordingly, we observed that disruption of SFXN4 decreases DNA repair in vitro (Fig. 4) and in vivo (Fig. 6) and increases the efficacy of platinum-based compounds and PARP inhibitors in a variety of ovarian cancer cell lines, including some with no known functional mutations in BRCA1/2 (A2780Cis, MDAH2774 (Table 1).