Menadione and ethacrynic acid inhibit the hypoxia-inducible factor (HIF) pathway by disrupting HIF-1α interaction with p300.

Abstract

Hypoxia is a general characteristic of most solid malignancies and intimately related to neoplastic diseases and cancer progression. Homeostatic response to hypoxia is primarily mediated by hypoxia inducible factor (HIF)-1α that elicits transcriptional activity through recruitment of the CREB binding protein (CBP)/p300 coactivator. Targeted blockade of HIF-1α binding to CBP/p300 would thus constitute a novel approach for cancer treatment by suppressing tumor angiogenesis and metastasis. Here, we identified inhibitors against the interaction between HIF-1α and p300 by a fluorescence polarization-based assay employing a fluorescently-labeled peptide containing the C-terminal activation domain of HIF-1α. Two small molecule inhibitors, menadione (MD) and ethacrynic acid (EA), were found to decrease expression of luciferase under the control of hypoxia-responsive elements in hypoxic cells as well as to efficiently block the interaction between the full-length HIF-1α and p300. While these compounds did not alter the expression level of HIF-1α, they down-regulated expression of a HIF-1α target vascular endothelial growth factor (VEGF) gene. Considering hypoxia-induced VEGF expression leading to highly aggressive tumor growth, MD and EA may provide new scaffolds for development of tumor therapeutic reagents as well as tools for a better understanding of HIF-1α-mediated hypoxic regulation.

• Authors: Yu-Ran Na, Ki-Cheol Han, Hyunsung Park, Eun Gyeong Yang
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 434 Issue 4 Pg. 879-84 (May 17 2013) ISSN: 1090-2104 [Electronic] United States
• PMID: 23618863 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2013 Elsevier Inc. All rights reserved.

Chemical References

• Hypoxia-Inducible Factor 1, alpha Subunit
• Vascular Endothelial Growth Factor A
• Vitamin K 3
• Luciferases
• E1A-Associated p300 Protein
• EP300 protein, human
• Ethacrynic Acid

Topics

• Binding Sites (genetics)
• Cell Hypoxia
• Cell Survival (drug effects)
• Dose-Response Relationship, Drug
• E1A-Associated p300 Protein (genetics, metabolism)
• Ethacrynic Acid (chemistry, pharmacology)
• Gene Expression (drug effects)
• HeLa Cells
• Humans
• Hypoxia-Inducible Factor 1, alpha Subunit (genetics, metabolism)
• Immunoblotting
• Luciferases (genetics, metabolism)
• Molecular Structure
• Protein Binding (drug effects)
• Protein Interaction Mapping (methods)
• Response Elements (genetics)
• Reverse Transcriptase Polymerase Chain Reaction
• Signal Transduction (drug effects)
• Vascular Endothelial Growth Factor A (genetics)
• Vitamin K 3 (chemistry, pharmacology)