To verify that the cytotoxic effects observed were selective, [125I]meta-iodobenzylguanidine (MIBG) was used as a nonspecific iodine-125 control, as it is not directed towards PARP-1 and would not be internalized by ovarian cancer cells due to the lack of norepinephrine transporter expression. This evidence concerns the gene PARP1 and ovarian cancer.