Protective effects of milimolar concentrations of WR-1065 against delayed genomic instability induced by irradiation in RKO36 cells. A) Frequency of mixed GFP+/− colonies in cultures pre-treated with 40 μM WR-1065 for 24 h before X-irradiation (■, WR-1065) or sham-treated (□, sham). The cultures were scored for GFP fluorescence 7 to 10 days after irradiation. Results are means of two independent experiments ±SEM, * p<0.05 versus sham-treated and irradiated control. B) Percentage of mixed GFP+/− colonies in cultures pre-treated with 40 μM WR-1065 for 24 h before iron ion irradiation (■, WR-1065) or sham-treated (□, sham). The cultures were scored for GFP fluorescence 7 to 10 days after irradiation. Results are means of two independent experiments ±SEM, * p<0.05 versus sham-treated and irradiated control. C) Percentage of binucleated cells containing micronuclei in cultures assayed 7 days after treatment with 40 μM WR-1065 for 24 h before X-irradiation (■, WR-1065) or sham-treated (□, sham). Results are means of four independent experiments ±SEM. D) Percentage of binucleated cells containing micronuclei in cultures assayed 7 days after treatment with 40 μM WR-1065 for 24 h before iron ion irradiation (■, WR-1065) or sham-treated (□, sham). Results are means of two independent experiments ±SEM, * p<0.05 versus sham-treated and irradiated control.