Exploring the radiosensitizing potential of magnetotherapy: a pilot study in breast cancer cells

Abstract

Aim: To explore the influence of electromagnetic fields (EMFs) on the cell cycle progression of MDA-MB-231 and MCF-7 breast cancer cell lines and to evaluate the radiosensitizing effect of magnetotherapy during therapeutic co-exposure to EMFs and radiotherapy.

Material and methods: Cells were exposed to EMFs (25, 50 and 100 Hz; 8 and 10 mT). In the co-treatment, cells were first exposed to EMFs (50 Hz/10 mT) for 30 min and then to ionizing radiation (IR) (2 Gy) 4 h later. Cell cycle progression and free radical production were evaluated by flow cytometry, while radiosensitivity was explored by colony formation assay.

Results: Generalized G1-phase arrest was found in both cell lines several hours after EMF exposure. Interestingly, a marked G1-phase delay was observed at 4 h after exposure to 50 Hz/10 mT EMFs. No cell cycle perturbation was observed after repeated exposure to EMFs. IR-derived ROS production was enhanced in EMF-exposed MCF-7 cells at 24 h post-exposure. EMF-exposed cells were more radiosensitive in comparison to sham-exposed cells.

Conclusions: These results highlight the potential benefits of concomitant treatment with magnetotherapy before radiotherapy sessions to enhance the effectiveness of breast cancer therapy. Further studies are warranted to identify the subset(s) of patients who would benefit from this multimodal treatment.

Keywords:

• Magnetotherapy
• breast cancer
• radiotherapy
• electromagnetic fields
• cell cycle
• oxidative stress

Acknowledgments

The authors thank Richard Davies for improving the English style of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was supported by the Fondo de Investigación Sanatoria [PI080728] and the Andalusian Council of Health [PI0730-2013] to M. I. Núñez. This research was also funded by the San Cecilio University Hospital, Granada.

Notes on contributors

M. M. Salinas-Asensio

M. M. Salinas-Asensio is associate professor in the Department of Physical Therapy, University of Granada, Granada, Spain.

S. Ríos-Arrabal

S. Ríos-Arrabal is a post doctoral researcher in the Department of Radiology and Physical Medicine, University of Granada, Granada, Spain.

F. Artacho-Cordón

F. Artacho-Cordón is assistant professor in the Department of Radiology and Physical Medicine, University of Granada, Granada, Spain.

M. A. Olivares-Urbano

M. A. Olivares-Urbano is a PhD student in the Department of Radiology and Physical Medicine, University of Granada, Granada, Spain.

I. Calvente

I. Calvente is a post doctoral researcher in the Department of Radiology and Physical Medicine, University of Granada, Granada, Spain.

J. León

J. León, a senior researcher at the Biosanitary Research Institute of Granada.

M. I. Núñez

M. I. Núñez is the head of the Department of Radiology and Physical Medicine, University of Granada, Granada, Spain.