Deciphering intracellular events triggered by mild magnetic hyperthermia in vitro and in vivo

Aim: To assess the cell response to magnetic nanoparticles under an alternating magnetic field by molecular quantification of heat responsive transcripts in two model systems. Materials & methods: Melanoma cells and Hydra vulgaris treated with magnetic nanoparticles were subjected to an alternating magnetic field or to macroscopic heating. Effect to these treatments were assessed at animal, cellular and molecular levels. Results: By comparing hsp70 expression following both treatments, thermotolerance pathways were found in both systems in absence of cell ablation or global temperature increment. Conclusion: Analysis of hsp70 transcriptional activation can be used as molecular thermometer to sense cells' response to magnetic hyperthermia. Similar responses were found in cells and Hydra, suggesting a general mechanism to the delivery of sublethal thermal doses.