Budget Amount *help |
¥18,850,000 (Direct Cost: ¥14,500,000、Indirect Cost: ¥4,350,000)
Fiscal Year 2010: ¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000)
Fiscal Year 2009: ¥5,330,000 (Direct Cost: ¥4,100,000、Indirect Cost: ¥1,230,000)
Fiscal Year 2008: ¥8,970,000 (Direct Cost: ¥6,900,000、Indirect Cost: ¥2,070,000)
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Research Abstract |
In order to establish a highly sensitive assay system for examining chemical mutagenesity and tumorigenesity, we performed KBrO_3-induced mutagenesis and tumorigenesis experiments using Ogg1-, Mutyh- or Msh2-deficient mice. We observed an enhanced tumor-formation in the small intestines of Mutyh- or Msh2-deficient mice, as compared with wild type and heterozygous mice. These results indicate that Mutyh- or Msh2-deficient mice are ideal animal models for examining tumorigenesity of chemicals of interest. The number of tumors was marginally increased in Ogg1-deficient mice in which the increased KBrO_3-induced mutagenesis was observed at an almost same extent as in Mutyh-deficient mice, suggesting that the induction of cell death might play a more important role than the suppression of mutagenesis for avoiding intestinal tumorigenesis caused by oxidative stress.
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