title: Hypoxia-inducible gene expression system using the erythropoietin enhancer and 3'-untranslated region for the VEGF gene therapy.
abstract: Gene therapy with the vascular endothelial growth factor (VEGF) gene is a potential treatment for many disorders or injuries with ischemia. However, unregulated expression of VEGF may induce pathological angiogenesis, promoting tumor growth, diabetic proliferative retinopathy and rupture of atherosclerotic plaque. Therefore, the effective regulation of the gene expression is one of the requirements for the VEGF gene therapy. In this research, we evaluated the hypoxia-inducible gene expression system with the erythropoietin (Epo) enhancer and the Epo 3'-untranslated region (UTR). The luciferase plasmids were constructed with the Epo enhancer (pEpo-SV-Luc), the Epo 3'-UTR (pSV-Luc-EpoUTR) or both (pEpo-SV-Luc-EpoUTR). The polyethylenimine/plasmid complexes were transfected to 293 or A7R5 cells and the cells were incubated under normoxia or hypoxia. The results showed that the Epo enhancer or Epo 3'-UTR increased the target gene expression under hypoxia. pEpo-SV-Luc-EpoUTR showed the highest luciferase expression. The VEGF expression plasmid with the Epo enhancer and 3'-UTR was also constructed. The VEGF expression by pEpo-SV-VEGF-EpoUTR showed the highest specificity of the gene expression in the hypoxic cells. The results suggest that the VEGF plasmid with the Epo enhancer and the Epo 3'-UTR may be useful for gene therapy for ischemic diseases.
authors.affiliation: Department of Bioengineering, College of Engineering, Hanyang University, Seoul, Korea.
authors.forename: Minhyung
authors.initials: M
authors.lastname: Lee
authors.forename: Donghoon
authors.initials: D
authors.lastname: Choi
authors.forename: Min Ji
authors.initials: MJ
authors.lastname: Choi
authors.forename: Ji Hoon
authors.initials: JH
authors.lastname: Jeong
authors.forename: Won Jong
authors.initials: WJ
authors.lastname: Kim
authors.forename: Seungjoon
authors.initials: S
authors.lastname: Oh
authors.forename: Yong-Hee
authors.initials: YH
authors.lastname: Kim
authors.forename: David A
authors.initials: DA
authors.lastname: Bull
authors.forename: Sung Wan
authors.initials: SW
authors.lastname: Kim
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics; D000818:Animals; D002460:Cell Line; D003001:Cloning, Molecular; D004742:Enhancer Elements, Genetic; D004797:Enzyme-Linked Immunosorbent Assay; D004921:Erythropoietin / Q000235:genetics*; D015870:Gene Expression / Q000502:physiology*; D015316:Genetic Therapy; D006801:Humans; D000860:Hypoxia / Q000235:genetics*; D008156:Luciferases / Q000235:genetics; D010957:Plasmids / Q000235:genetics; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics*
chemical_list: D020413:3' Untranslated Regions; D042461:Vascular Endothelial Growth Factor A; D004921:Erythropoietin; D008156:Luciferases