Natural background ionizing radiation is present on the earth’s surface; however, the biological role of this chronic low-dose-rate exposure remains unknown. The Researching the Effects of the Presence and Absence of Ionizing Radiation (REPAIR) project is examining the impacts of sub-natural background radiation exposure through experiments conducted 2 km underground in SNOLAB. The rock overburden combined with experiment-specific shielding provides a background radiation dose rate 30 times lower than on the surface. We hypothesize that natural background radiation is essential for life and maintains genomic stability and that prolonged exposure to sub-background environments will be detrimental to biological systems. To evaluate this, human hybrid CGL1 cells were continuously cultured in SNOLAB and our surface control laboratory for 16 weeks. Cells were assayed every 4 weeks for growth rate, alkaline phosphatase (ALP) activity (a marker of cellular transformation in the CGL1 system), and the expression of genes related to DNA damage and cell cycle regulation. A subset of cells was also exposed to a challenge radiation dose (0.1 to 8 Gy of X rays) and assayed for clonogenic survival and DNA double-strand break induction to examine if prolonged sub-background exposure alters the cellular response to high-dose irradiation. At each 4-week time point, sub-background radiation exposure did not significantly alter cell growth rates, survival, DNA damage, or gene expression. However, cells cultured in SNOLAB showed significantly higher ALP activity, a marker of carcinogenesis in these cells, which increased with longer exposure to the sub-background environment, indicative of neoplastic progression. Overall, these data suggest that sub-background radiation exposure does not impact growth, survival, or DNA damage in CGL1 cells but may lead to increased rates of neoplastic transformation, highlighting a potentially important role for natural background radiation in maintaining normal cellular function and genomic stability.
Skip Nav Destination
Article navigation
October 2024
REGULAR ARTICLES|
October 08 2024
The Role of Natural Background Radiation in Maintaining Genomic Stability in the CGL1 Human Hybrid Model System
Jake Pirkkanen;
aSchool of Natural Sciences, Laurentian University, Sudbury, Ontario, Canada
Search for other works by this author on:
Taylor Laframboise;
aSchool of Natural Sciences, Laurentian University, Sudbury, Ontario, Canada
Search for other works by this author on:
Jayden Peterson;
Jayden Peterson
aSchool of Natural Sciences, Laurentian University, Sudbury, Ontario, Canada
Search for other works by this author on:
Alyssa Labelle;
Alyssa Labelle
aSchool of Natural Sciences, Laurentian University, Sudbury, Ontario, Canada
Search for other works by this author on:
Forest Mahoney;
Forest Mahoney
aSchool of Natural Sciences, Laurentian University, Sudbury, Ontario, Canada
Search for other works by this author on:
Michel Lapointe;
Michel Lapointe
2
aSchool of Natural Sciences, Laurentian University, Sudbury, Ontario, Canada
Search for other works by this author on:
Marc S. Mendonca;
Marc S. Mendonca
bDepartment of Radiation Oncology, Radiation and Cancer Biology Laboratories, and Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana
Search for other works by this author on:
T.C. Tai;
T.C. Tai
aSchool of Natural Sciences, Laurentian University, Sudbury, Ontario, Canada
cMedical Sciences Division, Northern Ontario School of Medicine University, Sudbury, Ontario, Canada
Search for other works by this author on:
Simon J. Lees;
Simon J. Lees
cMedical Sciences Division, Northern Ontario School of Medicine University, Sudbury, Ontario, Canada
Search for other works by this author on:
Sujeenthar Tharmalingam;
Sujeenthar Tharmalingam
aSchool of Natural Sciences, Laurentian University, Sudbury, Ontario, Canada
cMedical Sciences Division, Northern Ontario School of Medicine University, Sudbury, Ontario, Canada
dHealth Sciences North Research Institute, Sudbury, Ontario, Canada
Search for other works by this author on:
Douglas R. Boreham;
Douglas R. Boreham
aSchool of Natural Sciences, Laurentian University, Sudbury, Ontario, Canada
cMedical Sciences Division, Northern Ontario School of Medicine University, Sudbury, Ontario, Canada
Search for other works by this author on:
Christopher Thome
Christopher Thome
3
aSchool of Natural Sciences, Laurentian University, Sudbury, Ontario, Canada
cMedical Sciences Division, Northern Ontario School of Medicine University, Sudbury, Ontario, Canada
dHealth Sciences North Research Institute, Sudbury, Ontario, Canada
3Corresponding author: Christopher Thome, NOSM University, 935 Ramsey Lake Road, Sudbury, Ontario, Canada, P3E 2C6; email: [email protected].
Search for other works by this author on:
Radiat Res (2024) 202 (4): 617–625.
Article history
Received:
November 22 2023
Accepted:
June 26 2024
Citation
Jake Pirkkanen, Taylor Laframboise, Jayden Peterson, Alyssa Labelle, Forest Mahoney, Michel Lapointe, Marc S. Mendonca, T.C. Tai, Simon J. Lees, Sujeenthar Tharmalingam, Douglas R. Boreham, Christopher Thome; The Role of Natural Background Radiation in Maintaining Genomic Stability in the CGL1 Human Hybrid Model System. Radiat Res 1 October 2024; 202 (4): 617–625. doi: https://doi.org/10.1667/RADE-23-00243.1
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