The relative biological effectiveness (RBE) of densely ionizing radiation can depend on the biological context. From a radiological perspective, age is an important factor affecting health risks of radiation exposure, but little is known about the modifying impact of age on the effects of densely ionizing radiation. Herein, we addressed the influence of age on leukemogenesis induced by accelerator-generated fast neutrons (mean energy, ∼2 MeV). Male C3H/HeNrs mice were exposed to 137Cs γ rays (0.2–3.0 Gy) or neutrons (0.0485–0.97 Gy, γ ray contamination 0.0105–0.21 Gy) at 1, 3, 8, or 35 weeks of age and observed over their lifetimes under specific pathogen-free conditions. Leukemia and lymphoma were diagnosed pathologically. Hazard ratio (HR) and RBE for myeloid leukemia mortality as well as the age dependence of these two parameters were modeled and analyzed using Cox regression. Neutron exposure increased HR concordant with a linear dose response. The increase of HR per dose depended on age at exposure, with no significant dose dependence at age 1 or 3 weeks but a significant increase in HR of 5.5 per Gy (γ rays) and 16 per Gy (neutrons) at 8 weeks and 5.8 per Gy (γ rays) and 9 per Gy (neutrons) at 35 weeks. The RBE of neutrons was 2.1 (95% confidence interval, 1.1–3.7), with no dependence on age. The development of lymphoid neoplasms was not related to radiation exposure. The observed increasing trend of radiation-associated mortality of myeloid leukemia with age at exposure supports previous epidemiological and experimental findings. The results also suggest that exposure at the susceptible age of 8 or 35 weeks does not significantly influence the RBE value for neutrons for induction of leukemia, unlike what has been documented for breast and brain tumors.
Skip Nav Destination
Article navigation
October 2024
REGULAR ARTICLES|
October 08 2024
Influence of Age on Leukemia Mortality Associated with Exposure to γ rays and 2-MeV Fast Neutrons in Male C3H Mice
Kentaro Ariyoshi;
aResearch Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
Search for other works by this author on:
Tatsuhiko Imaoka;
Tatsuhiko Imaoka
3
bDepartment of Radiation Effects Research, Institute for Radiological Science, National Institutes for Quantum Science and Technology, Chiba, Japan
Search for other works by this author on:
Yasushi Ohmachi;
aResearch Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
Search for other works by this author on:
Yuka Ishida;
Yuka Ishida
cLaboratory Animal and Genome Sciences Section, Department of Safety Administration, National Institutes for Quantum Science and Technology, Chiba, Japan
Search for other works by this author on:
Masahiro Uda;
aResearch Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
Search for other works by this author on:
Mayumi Nishimura;
Mayumi Nishimura
bDepartment of Radiation Effects Research, Institute for Radiological Science, National Institutes for Quantum Science and Technology, Chiba, Japan
Search for other works by this author on:
Mayumi Shinagawa;
Mayumi Shinagawa
bDepartment of Radiation Effects Research, Institute for Radiological Science, National Institutes for Quantum Science and Technology, Chiba, Japan
Search for other works by this author on:
Midori Yoshida;
aResearch Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
Search for other works by this author on:
Toshiaki Ogiu;
aResearch Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
Search for other works by this author on:
Mutsumi Kaminishi;
Mutsumi Kaminishi
5
bDepartment of Radiation Effects Research, Institute for Radiological Science, National Institutes for Quantum Science and Technology, Chiba, Japan
Search for other works by this author on:
Takamitsu Morioka;
Takamitsu Morioka
bDepartment of Radiation Effects Research, Institute for Radiological Science, National Institutes for Quantum Science and Technology, Chiba, Japan
Search for other works by this author on:
Shizuko Kakinuma;
Shizuko Kakinuma
bDepartment of Radiation Effects Research, Institute for Radiological Science, National Institutes for Quantum Science and Technology, Chiba, Japan
Search for other works by this author on:
Yoshiya Shimada
Yoshiya Shimada
3
bDepartment of Radiation Effects Research, Institute for Radiological Science, National Institutes for Quantum Science and Technology, Chiba, Japan
dInstitute for Environmental Sciences, Kamikita-gun, Aomori, Japan
Search for other works by this author on:
Radiat Res (2024) 202 (4): 685–696.
Article history
Received:
April 18 2023
Accepted:
July 23 2024
Citation
Kentaro Ariyoshi, Tatsuhiko Imaoka, Yasushi Ohmachi, Yuka Ishida, Masahiro Uda, Mayumi Nishimura, Mayumi Shinagawa, Midori Yoshida, Toshiaki Ogiu, Mutsumi Kaminishi, Takamitsu Morioka, Shizuko Kakinuma, Yoshiya Shimada; Influence of Age on Leukemia Mortality Associated with Exposure to γ rays and 2-MeV Fast Neutrons in Male C3H Mice. Radiat Res 1 October 2024; 202 (4): 685–696. doi: https://doi.org/10.1667/RADE-23-00069.1
Download citation file:
Sign in
Don't already have an account? Register
Client Account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.
Sign in via your Institution
Sign in via your Institution
37
Views
Citing articles via
Dosimetry: Was and Is an Absolute Requirement for Quality Radiation Research
Daniel Johnson, H. Harold Li, Bruce F. Kimler
Cutaneous Radiation Injuries: Models, Assessment and Treatments
Andrea L. DiCarlo, Aaron C. Bandremer, Brynn A. Hollingsworth, Suhail Kasim, Adebayo Laniyonu, Nushin F. Todd, Sue-Jane Wang, Ellen R. Wertheimer, Carmen I. Rios
Effects of Radiation on Blood Pressure and Body Weight in the Spontaneously Hypertensive Rat Model. Are Radiation Effects on Blood Pressure Affected by Genetic Background?
Norio Takahashi, Munechika Misumi, Yasuharu Niwa, Hideko Murakami, Waka Ohishi, Toshiya Inaba, Akiko Nagamachi, Satoshi Tanaka, Ignacia Braga Tanaka, III, Gen Suzuki
Studies of the Mortality of Atomic Bomb Survivors, Report 14, 1950–2003: An Overview of Cancer and Noncancer Diseases
Kotaro Ozasa, Yukiko Shimizu, Akihiko Suyama, Fumiyoshi Kasagi, Midori Soda, Eric J. Grant, Ritsu Sakata, Hiromi Sugiyama, Kazunori Kodama
The Technical and Clinical Implementation of LATTICE Radiation Therapy (LRT)
Xiaodong Wu, Naipy C. Perez, Yi Zheng, Xiaobo Li, Liuqing Jiang, Beatriz E. Amendola, Benhua Xu, Nina A. Mayr, Jiade J. Lu, Georges F. Hatoum, Hualin Zhang, Sha X. Chang, Robert J. Griffin, Chandan Guha