α-NF-dependent DNA strand break formation in B[a]P-7,8-dione-treated H358 cells. H358 cells were pretreated with 1 μm α-NF 1 h before B[a]P-7,8-dione treatment. The cells were then treated with B[a]P-7,8-dione for 6 h. At the end of the incubation, the cells were harvested and were used for the hOGG1-coupled comet assay. A, effects of 1 μm α-NF by itself. B, effects of 5.0 or 10 μm B[a]P-7,8-dione in the presence of 1 μm α-NF. Significant effects were found after α-NF treatment. *, p < 0.05. AU, arbitrary units.