Hypoxia-inducible factor inhibitors: a survey of recent patented compounds (2004 - 2010).

INTRODUCTION: Hypoxia-inducible factor (HIF) is a heterodimeric transcription factor consisting of α and β subunits that regulates the expression of angiogenic factors, including VEGF, which are involved in angiogenesis, invasion/metastasis, glucose uptake and cell survival during cancer development. AREAS COVERED: This review summarizes the information about patented HIF inhibitors over the last 7 years (2004 - 2010). The reader will gain an outline of the structure and biological activity of recently developed HIF inhibitors. EXPERT OPINION: Inhibition of HIF is an attractive therapeutic target for tumor angiogenesis and, until now, various HIF inhibitors have been discovered and evaluated. It is expected that development of more potent and selective HIF inhibitors will provide an effective treatment of cancer and other HIF-related diseases, including inflammation and cardiovascular disorder. As VEGF plays an important role in angiogenesis during tumor growth and ischemic diseases, the inhibition of VEGF-induced HIF is an attractive approach for the suppression of hypoxia-mediated pathological angiogenesis. HIF inhibitors may not only have cytostatic antitumor effects with fewer side effects, but also synergetic effects combined with radiotherapy.