Augmentation of erythropoietin enhancer-mediated hypoxia-inducible gene expression by co-transfection of a plasmid encoding hypoxia-inducible factor 1alpha for ischemic tissue targeting gene therapy.

Abstract

Therapeutic angiogenesis with gene encoding vascular endothelial growth factor (VEGF) is a potential treatment for ischemic diseases. However, VEGF expression should be tightly regulated to avoid side effects such as tumor growth. Previously, our group developed the erythropoietin (Epo) enhancer-SV40 promoter system for hypoxia-specific gene expression. In the present study, the activity of the Epo enhancer-SV40 promoter system was further enhanced without significant decrease in its specificity by co-transfection of the hypoxia-inducible factor 1alpha (HIF1alpha) gene. pSV-HIF1alpha was constructed by the insertion of the HIF1alpha cDNA into pSI. At a 1:1 ratio, co-transfection of pSV-HIF1alpha and pEpo-SV-Luc increased the promoter activity of the Epo enhancer-SV40 promoter system, showing at least three times higher gene expression under hypoxia as compared with the pEpo-SV-Luc single-plasmid transfection. Furthermore, co-transfection showed significant hypoxia specificity. Also, co-transfection of pEpo-SV-VEGF with pSV-HIF1alpha showed the enhanced VEGF expression without loss of hypoxia specificity, as compared with pEpo-SV-VEGF single-plasmid transfection. Furthermore, pSV-HIF1alpha induced the endogenous hypoxia-responsive genes such as angiopoietin-1, which would be beneficial for therapeutic angiogenesis. Therefore, with hypoxia specificity and higher gene expression, co-transfection of pSV-HIF1alpha and pEpo-SV-VEGF may be useful for ischemia targeting gene therapy.

• Authors: Suyeon Lee, Kyunghwa Kim, Hyun Ah Kim, Sung Wan Kim, Minhyung Lee
• Journal: Journal of drug targeting (J Drug Target) Vol. 16 Issue 1 Pg. 43-50 (Jan 2008) ISSN: 1061-186X [Print] England
• PMID: 18172819 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Actins
• HIF1A protein, human
• Hypoxia-Inducible Factor 1, alpha Subunit
• Vascular Endothelial Growth Factor A
• Erythropoietin
• Angiotensin I
• Luciferases

Topics

• Actins (biosynthesis)
• Angiotensin I (biosynthesis)
• Cell Line
• Enzyme-Linked Immunosorbent Assay
• Erythropoietin (physiology)
• Genetic Therapy (methods)
• Humans
• Hypoxia-Inducible Factor 1, alpha Subunit (biosynthesis, genetics)
• Kidney (cytology, metabolism)
• Luciferases (genetics)
• Plasmids (genetics)
• Promoter Regions, Genetic (genetics)
• Reverse Transcriptase Polymerase Chain Reaction
• Simian virus 40 (genetics)
• Transcription, Genetic (genetics)
• Transfection
• Vascular Endothelial Growth Factor A (pharmacology)