Article

Acriflavine inhibits HIF-1 dimerization, tumor growth, and vascularization.

Vascular Program, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 10/2009; 106(42):17910-5. DOI: 10.1073/pnas.0909353106
Source: PubMed

ABSTRACT HIF-1 is a heterodimeric transcription factor that mediates adaptive responses to hypoxia and plays critical roles in cancer progression. Using a cell-based screening assay we have identified acriflavine as a drug that binds directly to HIF-1alpha and HIF-2alpha and inhibits HIF-1 dimerization and transcriptional activity. Pretreatment of mice bearing prostate cancer xenografts with acriflavine prevented tumor growth and treatment of mice bearing established tumors resulted in growth arrest. Acriflavine treatment inhibited intratumoral expression of angiogenic cytokines, mobilization of angiogenic cells into peripheral blood, and tumor vascularization. These results provide proof of principle that small molecules can inhibit dimerization of HIF-1 and have potent inhibitory effects on tumor growth and vascularization.

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