Risk assessment and mechanism elucidation of carcinogenesis of childhood radiation exposure in hereditary high carcinogenic risk group

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K01938
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Childhood science (childhood environment science)
• Research Institution: National Institutes for Quantum and Radiological Science and Technology
• Principal Investigator: MORIOKA Takamitsu 国立研究開発法人量子科学技術研究開発機構, 放射線医学総合研究所 放射線影響研究部, 研究統括(定常) (70253961)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: Mlh1 / 放射線 / 大腸癌 / 子ども

Outline of Final Research Achievements

Children are especially sensitive to ionizing radiation. Recently, medical technologies have progressed rapidly for cancer diagnosis and treatments. Therefor, medical radiation exposure of children has been increasing.
The risk of colorectal cancer in the hereditary nonpolyposis colorectal cancer (HNPCC) patients is higher than that of healthy people. However, little is known about the carcinogenic risk of childhood exposure to radiation in hereditary high carcinogenic risk group of colorectal cancer. Hence, we examined the carcinogenic risk of childhood exposure to radiation using mouse model of HNPCC.
In this study, we found that carcinogenic risk of childhood exposure to radiation alone was not increased in HNPCC mouse model. On the other hand, the inflammatory bowel disease such as enteritis after radiation exposure may increase the colorectal carcinogenic risk in hereditary high carcinogenic risk group of colorectal cancer.

Free Research Field

実験病理

Academic Significance and Societal Importance of the Research Achievements

遺伝的に発癌リスクの高い集団の子どもが放射線被ばくした際の癌リスクについて、モデルマウスを用いて初めて明らかにしたことは、学術的に意義のあるものと考えられる。
今後、遺伝的に発癌リスクの高い子どもに対する放射線を利用した診断、治療を行う際に2次癌のリスク推定や生活習慣の改善を含む予防体制の確立、啓蒙活動へ繋がる成果である点で社会的に意義のあるものと言える。