Magnetic nano-Fe3O4 particles targeted gathering and bio-effects on nude mice loading human hepatoma Bel-7402 cell lines model under external magnetic field exposure in vivo.

Magnetic nano-Fe3O4 particles (MNPs), static magnetic field (SMF) and extremely low-frequency altering electric magnetic field (ELFF) were utilized to treat nude mice loading hepatoma Bel-7402 cell lines to investigate the therapeutic values of MNPs combined with ELFF in vivo. Magnetic resonance image (MRI) figures showed that about 98.9% MNPs injected into mice body through tail vein were gathered in tumor focal by SMF directing exposure. Single ELFF and MNPs treatments did not influence mice physiological function obviously. However, gathered MNPs combined with ELFF treatment prolonged mice survival time and inhibited loading tumor cells proliferation significantly compared to other mice groups (p < 0.05); furthermore, the tumor cells early apoptosis ratio of mice group was significantly higher than other groups (p < 0.05), and ELFF combined with gathered MNPs treatment improved tumor cells early apoptosis associated with Bcl group protein expression: Bax protein expression was higher than Bcl-2 and the combined treatment improved cells Heat shock protein-27 (Hsp-27) expression which could protect cells avoiding early apoptosis. The possible mechanism that this kind of combination inducing more cells into early apoptosis could be due to ELFF exposure influencing cells ion metabolism, MNPs strengthening the effects, and the ELFF vibrating MNPs to generate extra heat and activate cellular heat shock signal channel.