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Radiosensitivity of Cancer Stem Cells in Lung Cancer Cell Lines
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Selenium does not affect radiosensitivity of breast cancer cell lines
Daniela Schilling1,2, Birgit Herold3, Stephanie E Combs3,4,5
1Department of Radiation Oncology, Technische Universität München, School of Medicine, Klinikum rechts der Isar, Ismaninger Str. 22, 81675, Munich, Germany. daniela.schilling@tum.de.
Radiation and Environmental Biophysics
|June 16, 2019
Summary
Selenium supplementation does not reduce the effectiveness of radiation therapy for breast cancer. Studies show selenium does not protect cancer cells from radiation-induced damage or impair cell survival, suggesting it
Area of Science:
- Oncology
- Radiation Biology
- Nutritional Science
Background:
- Selenium is an antioxidant often given to breast cancer patients to mitigate radiation side effects.
- Concerns exist that selenium might protect tumor cells, potentially reducing radiotherapy efficacy.
Purpose of the Study:
- To investigate the impact of selenium on breast cancer cell radiosensitivity in vitro.
- To determine if selenium affects DNA damage, apoptosis, or clonogenic survival after radiation exposure.
Main Methods:
- Breast cancer cell lines (MDA-MB-231, MCF7) were treated with physiological selenium concentrations (70 and 140 µg/l).
- Cells were exposed to varying doses of X-ray irradiation (4-10 Gy).
- DNA double-strand breaks (γH2AX foci), apoptosis (caspase 3/7), and clonogenic survival were assessed.
Main Results:
- Selenium at physiological concentrations did not alter DNA double-strand breaks (γH2AX foci) after 4-Gy irradiation.
- Apoptosis (caspase 3/7) induction by 10-Gy irradiation was unaffected by selenium treatment.
- Selenium supplementation did not impair clonogenic survival of breast cancer cells post-irradiation (0-8 Gy).
Conclusions:
- Physiological selenium concentrations do not appear to compromise radiotherapy efficacy in breast cancer.
- Further randomized clinical trials are recommended to confirm these findings in patients regarding treatment effectiveness and side effects.
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