Abstract

Overview

Static magnetic field (SMF) influences on cell fates are broad but less explored concerning cancer stem cells (CSCs). This study focuses on osteosarcoma stem cells (OSCs), evaluating the effects of moderate-intensity SMF and its mechanism action.

Findings

• Prolonged SMF exposure enhanced proliferation and tumorsphere formation in K7M2 and MG63 OSCs.
• Notable increase in ferrous iron release and reactive oxygen species generation was observed in OSCs exposed to SMF.
• SMF triggered autophagic degradation of ferritin, activating specific pathways including microtubule-associated protein 1 light chain 3 (LC3) and nuclear receptor co-activator 4 (NCOA4), alongside the downregulation of ferritin heavy chain 1 (FTH1).
• The colony-forming ability of K7M2 OSCs, promoted by SMF, was substantially reduced by using siRNA against NCOA4.

Conclusion

This study presents first evidence linking moderate-intensity SMF with enhanced self-renewal abilities in OSCs via autophagic degradation of ferritin. Despite not affecting tumor volume or mass, SMF exposure favored pulmonary metastasis in a mouse model. The implications of this for human health need cautious interpretation due to the potential risks of electromagnetic fields influencing cancer metastasis.