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With the advancement of medicine, people can know and control more and more diseases. But human cancers are still menaced people’s health and life. So medicine researchers or doctors pay more attention to search the method of cure cancers. In the last few years, gene therapy has become a expectant hotpot of medicine. And in which suicide gene therapy has been used in clinical experimental trails for malignant tumors.Once a tumor grows beyond 1mm~3, angiogenesis must occur to support further growth. The ability to induce sustained angiogenesis is a necessary condition for both growth and metastasis. Hypoxia-inducible factor-1 is a transcription factor of major importance in the cellular response to oxygen deficiency. HIF-1α is stabilized under conditions of hypoxia and activates gene transcription by binding to the HRE in response to reduced oxygen tension.Therefore in this study we evaluated adnovirus mediated gene transfer of thymidine kinase confering tumor-specific sensitivity to ganciclovir. our results are as follows.1. We have successfully constructed two reporter plasmids HRE-luc and HRE-GFP with 5 copies of the HREs and fragments of the human vascular endothelial growth factor (VEGF) and the pGL3-promoter vector. Test plasmids and the control pSV- β -galactosidase plasmid were cotransfected into tumor cells by the calcium phosphate method. After 24 h hypoxia treatment, the reporter assay was performed. The plasmid HRE-luc showed significant increases in luciferase activity in response to hypoxia. And the plasmid HRE-GFP also showed significant increases in GFP activity in response to hypoxia. So the HREs can be used in the following experiments, and the reporter plasmids are also useful tools for screening of the drugs that inhibit the expression and transcription activity of HIF-1.2. Used the homologous recombination technique we constructed two recombinant adenoviruses Ad-SV-TK and Ad-HRE-TK which expressing HSV-TK.