Figure 5.

Effect of Ape1/Ref-1 inhibitors on estrogen-responsive gene expression. MCF-7 cells were incubated with DMSO, MX, or E3330 for 1 h and then treated with ethanol (−E₂ or white bars) or 10 nm E₂ (+E₂ or black bars) for 24 h. A, Cell lysates were prepared and separated on a denaturing acrylamide gel. The blot was subjected to Western analysis with an antibody that recognizes Ape1/Ref-1 or GAPDH. B, RNA was isolated, cDNA was synthesized, and real-time PCR was carried out with gene-specific primers. The relative fold change was determined using the comparative C_t method with the housekeeping gene, 36B4, serving as the internal control. Data from four independent experiments, which had been done in duplicate, were combined and are presented as the mean ± sem. ANOVA with a post hoc Student’s t test was used to detect significant differences in mRNA levels in response to E₂ (*, P < 0.05) or the inhibitor E3330 (#, P < 0.05).