Amphotericin B represses the CAD of HIF-1α. (A) Structures of HIF-1α mutants. The expressions of HIF-1α mutants were verified by Western blotting. N indicates normoxia; H, hypoxia; and DFO, 130 μM desferrioxamine. (B) AmB repression of expressed wild-type HIF-1α. The plasmid for HIF-1α was cotransfected with the EpoE reporter into HEK293 cells. After incubation under normoxic (N) or hypoxic (H) conditions for 16 hours with sodium deoxycholate or AmB, luciferase activities were determined. (C) AmB repression of stably expressed, hypoxia-activated HIF-1α mutant. The plasmid for a stable, hypoxia-activated HIF-1α mutant (sh-HIF-1α) was cotransfected with the EpoE reporter into HEK293 cells. The cells were incubated under normoxic or hypoxic conditions for 16 hours with sodium deoxycholate or AmB. (D) Asn803 is required for AmB repression. The plasmid for a stable, constitutively activated HIF-1α mutant (sc-HIF-1α, Asn803Ala) was cotransfected with the EpoE reporter into HEK293 cells. The cells were incubated under normoxic or hypoxic conditions for 16 hours with sodium deoxycholate or AmB. Results are expressed as relative values versus the normoxic activity in the untransfected cells and are plotted as the means ± SD of 12 experiments. ^*P < .05 versus the hypoxic control.