Hypoxia has been identified as a common environmental stress factor associated with therapeutic resistance and metastasis in human cancers.A major player in regulating the response to hypoxia is the transcriptional factor hypoxia-inducible factor 1 alpha (HIF-1α).Although HIF-1α is well known to be stabilized under hypoxia,the regulatory mechanism of HIF-1α signaling in malignant cells is not fully understood.In a recent paper,Yuan et al.1 identified a novel pathway that acts as a ‘vicious cycle\'to amplify HIF- 1 activation in prostate cancer cells,hence suggesting potential biomarkers that may predict progression and poor prognosis in human prostate cancer (Figure 1).