Direct effect of radiation and chemicals on human tissues and its mechanism

2014 Fiscal Year Final Research Report

• Project/Area Number: 23241023
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Risk sciences of radiation/Chemicals
• Research Institution: 独立行政法人医薬基盤研究所
• Principal Investigator: NOMURA Taisei 独立行政法人医薬基盤研究所, 難病・疾患資源研究部, プロジェクトリーダー (90089871)
• Co-Investigator(Kenkyū-buntansha): RYO Haruko 独立行政法人医薬基盤研究所, 難病・疾患資源研究部, サブプロジェクトリーダー (90301267) ; TODO Takeshi 大阪大学, 医学(系)研究科(研究院), 教授 (90163948) ; MURAKAMI Masao 神戸大学, 医学(系)研究科(研究院), 教授 (50210018) ; FUJIKAWA Kazuo 近畿大学, 理工学部, 教授 (90247958)
• Co-Investigator(Renkei-kenkyūsha): YOSHIDOME Katsuhide 独立行政法人医薬基盤研究所, 客員研究員 (80598813) ; NAKAJIMA Hiroo 大阪大学, 医学(系)研究科(研究院), 助教 (20237275) ; AKAGI Takashi 神戸大学, 医学(系)研究科(研究院), 研究員 (50500005)
• Project Period (FY): 2011-04-01 – 2015-03-31
• Keywords: 放射線、粒子線、X線 / 化学物質 / ヒト臓器・組織 / Super-SCID / 環境有害物質 / 人体影響 / メカニズム / 感受性

Outline of Final Research Achievements

Direct effects of radiation and chemicals on cancer and normal tissues were detected using our super-SCID mouse system which maintains human organs/tissues for long period. Dose dependent suppressive effects of X/gamma-rays, neutron, proton, helium and carbon ions on cancer growth were compared, yielding relative biological effectiveness (RBE). RBE was C>>He>X in lung cancer, C>He=X in prostate cancer, C>X in pancreatic cancer, and C>P≧X in all the three cancer tissues. RBE of carbon ion for changes in gene expression was 4.6 in the normal lung tissues, the value being similar to the RBE (approx. 5) of suppressive effects in the lung cancer tissues. RBE of carbon ion for changes of gene expression was also similar to that of neutron (4.2) in the normal thyroid tissues, but affected gene groups were different. Very small doses of TCDD to the transplanted thyroid tissues suppressed thyroid hormone secretion.

Free Research Field

放射線基礎医学、実験病理学、医遺伝学、環境科学