Synergistic Effect of Combined Treatment with Magnetic Hyperthermia and Magneto-Mechanical Stress of Breast Cancer Cells

Abstract

With the development of nanotechnology, the emergence of new anti-tumor techniques using nanoparticles such as magnetic hyperthermia and magneto-mechanical activation have been the subject of much attention and study in recent years, as anticancer tools. Therefore, the purpose of the current in vitro study was to investigate the cumulative effect of a combination of these two techniques, using magnetic nanoparticles against breast cancer cells. After 24 h of incubation, human breast cancer (MCF-7) and non-cancerous (MCF-10A) cells with and without MNPs were treated (a) for 15 min with magnetic hyperthermia, (b) for 30 min with magneto-mechanical activation, and (c) by a successive treatment consisting of a 15-min magnetic hyperthermia cycle and 30 min of magneto-mechanical activation. The influence of treatments on cell survival and morphology was studied by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide) assay and light microscopy. When applied, separately, magneto-mechanical and thermal (hyperthermia) treatment did not demonstrate strong reduction in cell viability. No morphological changes were observed in non-cancerous cells after treatments. On the other hand, the combination of magneto-mechanical and thermal treatment in the presence of MNPs had a synergistic effect on decreased cell viability, and apoptosis was demonstrated in the cancer cell line. Synergism is most evident in the cancer cell line, incubated for 120 h, while in the non-cancerous line after 120 h, an increase in proliferation is clearly observed. MCF-7 cells showed more rounded cell morphology, especially after 120 h of combined treatment.