TOPOISOMERASE INHIBITORS ENHANCE THE CYTOCIDAL EFFECT OF AAV-HSVTK/GANCICLOVIR ON CANCER CELLS
Project/Area Number |
14571627
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Otorhinolaryngology
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Research Institution | University of the Ryukyus |
Principal Investigator |
SHINHAMA Akihiko University of the Ryukyus, Faculty of Medicine, Department of Otorhinolaryngology-Head and Neck Surgery, Instructor, 医学部, 助手 (60284973)
|
Co-Investigator(Kenkyū-buntansha) |
KOUCHI Ayako University of the Ryukyus, Faculty of Medicine, Department of Otorhinolaryngology-Head and Neck Surgery, Instructor, 医学部, 助手 (30264500)
GANAHA Akira University of the Ryukyus, Faculty of Medicine Hospital, Department of Otorhinolaryngology, Instructor, 医学部附属病院, 助手 (00347155)
玉城 三七夫 琉球大学, 医学部附属病院, 助手 (80325844)
大輪 達仁 琉球大学, 医学部, 助手 (60284981)
長谷川 昌宏 琉球大学, 医学部附属病院, 助手 (10347156)
金澤 丈治 琉球大学, 医学部附属病院, 講師 (20336374)
|
Project Period (FY) |
2002 – 2004
|
Project Status |
Completed (Fiscal Year 2004)
|
Budget Amount *help |
¥3,400,000 (Direct Cost: ¥3,400,000)
Fiscal Year 2004: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2003: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 2002: ¥1,400,000 (Direct Cost: ¥1,400,000)
|
Keywords | Adeno-associated virus vector / Head and Neck Cancer / Chemotherapy / Suicide Gene / Combined Therapy |
Research Abstract |
Adeno-associated virus(AAV) is a nonpathogenic virus with a single-strand DNA genome. AAV vectors have several unique properties suited for gene therapy applications. However, an obstacle to their application is a low efficiency of transgene expression, mainly due to a limited second-strand synthesis. In the present study, we investigated whether topoisomerase inhibitors (etoposide and camptothecin) enhance the AAV vector-mediated transgene expression and the killing effect by AAVtk/GCV system. The enhancement of transgene expression was observed in a concentration-dependent manner on human laryngeal carcinoma cells (HEp-2 cells) and HeLa cells. Southern analysis confirmed that etoposide enhanced the double-strand synthesis of the AAV vector genome in HEp-2 cells and HeLa cells. The cells were efficiently killed by AAVtk/GCV system, as expected. More importantly, both etoposide and camptothecin augmented the cytocidal effect of the AAVtk/GCV system. Following the in vitro experiments, we evaluated the transgene expression and the antitumor activity of the AAV vectors in nude mice inoculated with HEp-2 subcutaneously. The LacZ expression was observed in the xenografted tumors and the AAVtk/GCV system suppressed the tumors growth compared with any other control such as AAVLacZ/GCV, AAVtk/PBS. These findings suggest that the combination of AAV-mediated suicide gene therapy and treatment with topoisomerase inhibitors may have synergistic therapeutic effects in the treatment of cancers.
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Report
(4 results)
Research Products
(1 results)