Enhanced Antiproliferative Activity of Docetaxel by Extremely Low Frequency Electromagnetic Fields in MCF-7 Breast Cancer Cells

Background/Objectives: Breast cancer remains one of the leading causes of cancer-related mortality in women. While ongoing efforts seek new treatment options, improving the efficacy of existing therapies is equally crucial. Despite advancements in chemotherapy, severe side effects continue to limit treatment success. Combining therapies to enhance efficacy is a promising strategy. Emerging evidence suggests that electromagnetic fields (EMF) can act as chemotherapy enhancers, potentially allowing for lower drug doses. One proposed mechanism is the elevation of reactive oxygen species (ROS), which contributes to cell death. This study explores whether such enhancement exists for chemotherapeutics like docetaxel, where ROS is not the primary, but a contributing, mechanism of action. Methods: We investigated the effects of 50 Hz, 20 mT extremely low-frequency EMF (ELF-EMF) exposure to MCF-7 breast cancer cells in the presence of docetaxel. Cytotoxicity was assessed using the MTT assay, while apoptosis, ROS generation, and cell cycle distribution were analyzed via flow cytometry. Morphological changes associated with apoptosis were examined using acridine orange/propidium iodide dual staining and fluorescence microscopy. Results: Results showed that 50 μM docetaxel reduced cell viability by 50%, while the combination of ELF-EMF and docetaxel achieved the same effect at a significantly lower docetaxel concentration (14 μM). Flow cytometry revealed similar G2/M phase arrest and apoptotic cell death in the combined treatment group, along with elevated ROS levels. Conclusions: These findings suggest that ELF-EMF can potentiate the effects of docetaxel, even when ROS is not the dominant mechanism, supporting its potential as a complementary therapy in breast cancer treatment.