Hypoxia-inducible factor-1 (HIF-1) is a transcription factor that controls genes involved in glycolysis, angiogenesis, migration, and invasion. Echinomycin is a cell-permeable inhibitor of HIF-1-mediated gene transcription. It acts by intercalating into DNA in a sequence-specific manner, blocking the binding of either HIF-1α or HIF-1β to the hypoxia-responsive element. Echinomycin reversibly inhibits hypoxia-induced HIF-1 transcription activity in U215 cells with an EC50 value of 1.2 nM. It inhibits hypoxia-induced expression of vascular endothelial growth factor, blocking angiogenesis and altering excitatory synaptic transmission in hippocampal neurons. Echinomycin also impairs expression of survivin, enhancing the sensitivity of multiple myeloma cells to melphalan.
