Ref-1/APE1 knockdown in A2780 (nuclear Ref-1/APE1) and CP70 (cytoplasmic Ref-1/APE1) cells sensitizes both to cisplatin.189 In SKOV3 and A2780 cells, Ref-1/APE1 siRNA significantly reduces cell proliferation, colony formation, migration and invasion.187, 192 Similarly, Ref-1/APE1 siRNA treatment of SKOV-3x ovarian cells significantly reduces their growth; the same occurs with APX3330 redox inhibition.11, 29 Ref-1/APE1 siRNA cells implanted subcutaneously in mice show markedly reduced growth compared to control tumors: a 3.2-fold increase in tumor-doubling time (from 5 to more than 15 days). This evidence concerns the gene APEX1 and neoplasm.