The effect of local irradiation on lung tumor formation in Af mice
Keywords:
ionizing radiation, carcinogenesis, laboratory mice, lung tumorsAbstract
Studies of the biological effects of ionizing radiation have recently become actual due to the expansion of the implement of nuclear technologies in a variety of human activities. Especially it important for using of medical imaging when human body is often exposed by low-dose ionizing radiation. Ionizing radiation at low doses is the cause of stochastic effects, which are depended on influence by many another factors, such as the genetic predisposition or chemical environmental pollutants.
The aim of this study was to investigate the effect of spontaneous and chemically induced tumor formation in the lungs of Af mice after local X-ray irradiation of the thoracic region.
Af mice of both sexes were 3 months old at the start of the study. Animals were irradiated using an X-Rad 320 Precision X-ray Inc. biological X-ray system. Local irradiation of the thoracic region was achieved by shielding with protective plates. Fractionated local irradiation of the thoracic region of Af mice with a total dose of 5 Gy increase the frequency of spontaneous lung tumors. Both the percentage of animals with tumors (up to 48,7% versus 27% in controls) and the number of tumors per mouse (up to 1,24 versus 0,86 in controls) grew up.
Neither worsening of general health status nor growth of tumor rates were found after repeated (every two weeks for 9 months) local irradiation by radiography doses. Thus, we concluded that repeated local radiography low-dose irradiation did not affect the rate of spontaneous lung carcinogenesis in Af mice. But in combination with urethane solution repeated irradiation by radiography doses stimulated chemically induced carcinogenesis in the lungs of Af mice: increased in the number and size of tumors.
References
- Ulsh BA. The new radiobiology: returning to our roots. Dose Response. 2012; 10(4):593–609.
- UNSCEAR 2024 Report Volume I. Sources, effects and risks of ionizing radiation [Internet, cited 10 August 2025]. Available fom: https://www.unscear.org/unscear/en/publications/2024_1.html.
- Ilin LA, Kirilov VF, Korenkov IP. Radiatsionnaya gygyena: uchebnik dlia vuzov [Radiation Hygiene: A Textbook for Universities]. Moscow: GEOTAR-Media; 2010. 384 p. Russian.
- Hauptmann M, Byrnes G, Cardis E, et al. Brain cancer after radiation exposure from CT examinations of children and young adults: results from the EPI-CT cohort study. Lancet Oncol. 2023;24(1):45–53. Doi: 10.1016/S1470-2045(22)00655-6.
- Hamada N. Cancer and Non-Cancer Effects Following Ionizing Irradiation. Cancers (Basel). 2024;16(6):1141. Doi: 10.3390/cancers16061141.
- Sykes PJ, Day TK, Swinburne SJ, et al. In vivo mutagenic effect of very low dose radiation. Dose Response. 2006;4(4):309–16. Doi: 10.2203/dose-response.06-004.Sykes.
- Timokhina NI, Nadyrov EA, Veyalkina NN, et al. Geneticheski-obuslovlennoe obrazovanie opuholey v legkih myshey linii Af pry vliyanii radiatsionnogo i himicheskogo faktorov, I starenii [Genetically-caused tumor formation in lungs of mice of line Af under influence of radiation and chemical factors, and at aging]. Journal of Anatomy and Histopathology. 2018;7(3):56–60. Russian.
- Piotrowski I, Kulcenty K, Suchorska WM, et al. Carcinogenesis Induced by Low-dose Radiation. Radiol Oncol. 2017;51(4):369–377. Doi: 10.1515/raon-2017-0044.]
- Hauptmann M, Daniels RD, Cardis E, et al. Epidemiological Studies of Low-Dose Ionizing Radiation and Cancer: Summary Bias Assessment and Meta-Analysis. Journal of the National Cancer Institute Monographs. 2020;2020(56):188–200. Doi: 10.1093/jncimonographs/lgaa010.
- Kitahara CM, Linet MS, Rajaraman P, et al. New Era of Low-Dose Radiation Epidemiology. Curr Environ Health Rep. 2015;2(3):236–249. Doi: 10.1007/s40572-015-0055-y. PMID: 26231501; PMCID: PMC10267798.
- Goncharov SV, Cheshik IA. Modifikatsiya opuholevyh effektov v legkih laboratornyh myshey ekstraktami lishynikov [Modifying the tumor effects in the lungs of laboratory mice with lichen extracts]. Doklady Natsionalnoi akademii nauk Belarusi [Doklady of the National Academy of Sciences of Belarus]. 2021; 65(4):474–483. Russian.
- European Union. 2010. Directive 2010/63/EU of the European Parliament and of the Council of 22 September 2010 on the protection of animals used for scientific purposes Official Journal of the European Union. L276/33.
- Paunesku T, Stevanović A, Popović J. Effects of low dose and low dose rate low linear energy transfer radiation on animals – review of recent studies relevant for carcinogenesis. International Journal of Radiation Biology. 2021;97(6):757–768. Doi: 10.1080/09553002.2020.1859155.
- Yamada Y, Iwata KI, Blyth BJ. Effect of Age at Exposure on the Incidence of Lung and Mammary Cancer after Thoracic X-Ray Irradiation in Wistar Rats. Radiation Research. 2017;187(2):210–220. Doi: 10.1667/RR14478.1. Epub 2017 Jan 30.
- Munley MT, Moore JE, Walb MC, et al. Cancer-prone mice expressing the Ki-rasG12C gene show increased lung carcinogenesis after CT screening exposures. Radiation Research. 2011;176(6):842–848.
- Miller MS, Moore JE, Walb MC, et al. Chemoprevention by N-acetylcysteine of low-dose CT-induced murine lung tumorigenesis. Carcinogenesis. 2013;34(2):319–324.
