HIF-1α repression by amphotericin B is recovered by inhibition of FIH. (A) Recovery of AmB-repressed HIF-1α activity by FIH inhibitors. Hep3B cells transfected with Gal4-CAD plasmid were treated with desferrioxamine (DFO) or DMOG at various concentrations and incubated under hypoxic conditions in the presence of AmB (5 μg/mL) for 16 hours. Results are plotted as the means ± SD of 12 experiments. ^*P < .05 versus the hypoxic, AmB-treated group. (B) Recovery of AmB-inhibited HIF-1 target gene expression by FIH inhibitors. Hep3B cells were subjected to normoxia (N, lane 1) or 16 hours of hypoxia (H, lanes 2-7) in the presence of sodium deoxycholate (lanes 1-2) or 10 μg/mL AmB (lane 3). Cells were cotreated with AmB and various DMOG concentrations (lanes 4-7). mRNAs of HIF-1 target genes and β-actin were isolated and analyzed by semiquantitative RT-PCR. The data shown are representative of 3 separate experiments.