Genome Integrity

ORIGINAL ARTICLE
Year
: 2019  |  Volume : 10  |  Issue : 1  |  Page : 3-

Radiation-induced Chromosome Instability: The role of dose and dose rate


Eman Mohammed Elbakrawy1, Mark A Hill2, Munira A Kadhim4 
1 Department of Biological and Medical Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, England, UK; Department of Radiation Physics, National Center for Radiation Research and Technology, Atomic Energy Authority, Nasr City, Cairo, Egypt
2 Department of Oncology, Gray Laboratories, CRUK/MRC Oxford Institute for Radiation Oncology, University of Oxford, Oxford, England, UK

Correspondence Address:
Munira A Kadhim
Department of Biological and Medical Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Gipsy Lane, Headington, Oxford OX3 0BP
UK

Nontargeted effects include radiation-induced genomic instability (RIGI) which is observed in the progeny of cells exposed to ionizing radiation and can be manifested in different ways, including chromosomal instability and micronucleus (MN) formation. Since genomic instability is commonly observed in tumors and has a role in tumor progression, RIGI has the potential of being an important mechanism for radiation-induced cancer. The work presented explores the role of dose and dose rate on RIGI, determined using a MN assay, in normal primary human fibroblast (HF19) cells exposed to either 0.1 Gy or 1 Gy of X-rays delivered either as an acute (0.42 Gy/min) or protracted (0.0031 Gy/min) exposure. While the expected increase in MN was observed following the first mitosis of the irradiated cells compared to unirradiated controls, the results also demonstrate a significant increase in MN yields in the progeny of these cells at 10 and 20 population doublings following irradiation. Minimal difference was observed between the two doses used (0.1 and 1 Gy) and the dose rates (acute and protracted). Therefore, these nontargeted effects have the potential to be important for the low-dose and dose-rate exposure. The results also show an enhancement of the cellular levels of reactive oxygen species after 20 population doublings, which suggests that ionising radiation (IR) could potentially perturb the homeostasis of oxidative stress and so modify the background rate of endogenous DNA damage induction. In conclusion, the investigations have demonstrated that normal primary human fibroblast (HF19) cells are susceptible to the induction of early DNA damage and RIGI, not only after a high dose and high dose rate exposure to low linear energy transfer, but also following low dose, low dose rate exposures. The results suggest that the mechanism of radiation induced RIGI in HF19 cells can be correlated with the induction of reactive oxygen species levels following exposure to 0.1 and 1 Gy low-dose rate and high-dose rate x-ray irradiation.


How to cite this article:
Elbakrawy EM, Hill MA, Kadhim MA. Radiation-induced Chromosome Instability: The role of dose and dose rate.Genome Integr 2019;10:3-3


How to cite this URL:
Elbakrawy EM, Hill MA, Kadhim MA. Radiation-induced Chromosome Instability: The role of dose and dose rate. Genome Integr [serial online] 2019 [cited 2019 Nov 19 ];10:3-3
Available from: http://www.genome-integrity.org/article.asp?issn=2041-9414;year=2019;volume=10;issue=1;spage=3;epage=3;aulast=Elbakrawy;type=0