Elucidation of the mechanisms of low dose, low dose-rate radiation induced mammary cancer through the interaction between mammary stem cells and their microenvironment

2017 Fiscal Year Final Research Report

• Project/Area Number: 26340024
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Risk sciences of radiation and chemicals
• Research Institution: National Institutes for Quantum and Radiological Science and Technology (2017); Hiroshima University (2014-2016)
• Principal Investigator: IIZUKA DAISUKE 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, 主任研究員(定常) (00455388)
• Co-Investigator(Kenkyū-buntansha): 神谷 研二 広島大学, 医療政策室, 特任教授 (60116564) ; 笹谷 めぐみ (豊島めぐみ) 広島大学, 原爆放射線医科学研究所, 准教授 (80423052)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: 放射線誘発乳がん / 乳腺微小環境 / 乳腺幹細胞

Outline of Final Research Achievements

Epidemiological studies have suggested that the risk of breast cancer incidence in A-bomb survivors is higher than any other sites. The molecular mechanisms of low dose, low dose-rate radiation induced breast cancer have not been clearly demonstrated yet. Tissue stem cells are one of critical target for carcinogenesis. To clarify the molecular mechanisms of low dose, low dose-rate radiation induced breast cancer, we focused on the interaction between mammary stem cells and their microenvironment after radiation exposure.
We observed here that mammary stem cells were increased in a strain- and dose-rate- dependent manner when mammary gland was irradiated at 4 weeks of age. We also observed the increase of tumor growth rate in radiation chimera model, which recapitulate the direct effect of tumor induction by irradiated mammary microenvironment.

Free Research Field

放射線生物学