Effects of oxygenation on radiosensitivity for hypoxic tumor cells.

• Project/Area Number: 24591844
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Radiation science
• Research Institution: Osaka University
• Principal Investigator: OGAWA KAZUHIKO 大阪大学, 医学(系)研究科(研究院), 教授 (40253984)
• Co-Investigator(Kenkyū-buntansha): MATSUSHITA Masayuki 琉球大学, 医学部, 教授 (30273965) ; ISHIUCHI Syogo 琉球大学, 医学(系)研究科(研究院), 教授 (10312878) ; YOSHIMI Naoki 琉球大学, 医学(系)研究科(研究院), 教授 (30166996) ; KOSHI Kiyotaka 琉球大学, 医学部附属病院, その他 (90195660)
• Co-Investigator(Renkei-kenkyūsha): MURAYAMA Sadayuki (60239548)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000); Fiscal Year 2014: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000); Fiscal Year 2013: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2012: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000)
• Keywords: 低酸素腫瘍細胞 / 放射線抵抗性に関わる機序 / 放射線治療効果 / 遺伝子発現 / 酸素化 / 放射線抵抗性にかかわる機序

Outline of Final Research Achievements

This study has investigated the effects and the mechanisms of oxygenation on radiosensitivity for hypoxic malignant tumor cells. Our results have indicated that hypoxic tumor cells irradiated under hypoxic conditions and oxygenation had significantly slow growth compared to those irradiated under hypoxic contitions. Furthermore, concering in vivo group treated by irradiation and hyperbaric oxygennation, 78 genes have down-regulated compared to the group treated by irradiation without HBO. Especillay, hypoxia and HIF-1-related genes, such as vascular endothelial growth factor and Insulin-like growth factor-binding protein, have prominently down-regulated. These results indicate that oxygenation affects and tumor growth delay and changes of gene expression for hypoxic tumor cells.