The normal pancreas has an abundant blood flow, in contrast to pancreatic cancer, which is a hypovascular tumor. During hypoxia under a hypovascular environment, the transcription factor hypoxia-inducible factor-1α (HIF-1α) is activated. High HIF-1α expression reduces sensitivity to gemcitabine (GEM) which is used as a treatment for pancreatic can...

RATIONALE Hypoxia-inducible factor-1α (HIF-1α), an oxygen (O2)-sensitive transcription factor, mediates transcriptional responses to low-O2 tension states. Although acute hypoxia causes pulmonary vasoconstriction and chronic hypoxia can cause vascular remodeling and pulmonary hypertension, conflicting data exist on the role of HIF-1α in modulating pulmonary vascular tone. OBJECTIVE To investi...

HIF-1 is the master regulator of cellular hypoxia response; the oxygen sensitive HIF-1α subunit transactivates its own expression in hypoxia via a hypoxia response element (HRE) in the promoter of the HIF-1α gene. This transactivation loop significantly contributes to the build up of HIF-1α at the onset of hypoxia, with the binding of HIF-1 to the HIF-1α promoter being dependent on the epigenet...

The present study examined the downregulation of survivin expression by hypoxia-inducible factor-1α (HIF-1α) miRNA and its effect in the inhibition of A549 cell growth in vitro and in vivo. Survivin expression, apoptosis, proliferation and migration under normoxic and hypoxic conditions were assessed by standard methods. Cotransfection and chromatin immunoprecipitation were used to observe the ...

Trichostatin A (TSA) is an anticancer drug that inhibits histone deacetylases (HDACs). Hypoxia-inducible factor 1 (HIF-1) participates in tumor angiogenesis by upregulating target genes, such as vascular endothelial growth factor (VEGF). In the present study, we investigated whether TSA treatment increases HIF-1α stabilization via acetylation under normoxic conditions, which would lead to VEGF ...

The present study aimed to evaluate the expression of hypoxia-inducible factor-1α (HIF-1α) and MDR1/P-glycoprotein (P-gp) in human laryngeal squamous cell carcinoma (LSCC) tissues, and also to investigate the regulation of MDR1 gene expression by HIF-1α in Hep-2 cells under hypoxic conditions. The expression of HIF-1α and MDR1/P-gp in human LSCC tissues was examined using immunohistochemistry. ...

Hypoxia inducible factor-1α (HIF-1α) is associated with human breast cancer chemoresistance. Various reports have suggested that multiple pathways are involved in HIF-1α induction and that the molecular mechanisms regulating HIF-1α-induced chemoresistance are still not fully understood. Here, we report that anterior gradient 2 (AGR2), a proposed breast cancer biomarker, is an essential regulato...

Overexpression of HIF-1α, a transcription factor responsive to hypoxia, is frequently observed in malignant tumors, which sometimes show resistance to chemotherapy and radiation therapy. Consequently, decrease of HIF-1α through virotherapy offers a logical strategy for the treatment of aggressive tumors. In this study, we found that infection with the oncolytic H-1 parvovirus decreased HIF-1α p...

OBJECTIVE To explore angiogenesis in osteosarcoma under the condition of hypoxia-inducible factor (HIF)-1α gene silenced by small interference RNA (siRNA). METHODS The SaOS-2 osteosarcoma cells, transfected with the recombinant plasmid pSilencer2.1-HIF-1α or pSilencer2.1-SCR, were classified as HIF-1α/siRNA group or SCR/siRNA group, respectively. In which, vascular endothelial growth factor (...

The aim of this study was to investigate the mechanism of propranolol on the regression of hemangiomas. Propranolol-treated hemangioma tissues were collected and the expression of hypoxia inducible factor-1α (HIF-1α) was examined. We also established HIF-1α overexpression and knockdown hemangioma cells, and determined the effects of HIF-1α on the hemangioma cells proliferation, apoptosis, migra...