Therapeutic mechanism of treating SMMC-7721 liver cancer cells with magnetic fluid hyperthermia using Fe(2)O(3) nanoparticles

This study aimed to investigate the therapeutic mechanism of treating SMMC-7721 liver cancer cells with magnetic fluid hyperthermia (MFH) using Fe(2)O(3) nanoparticles. Hepatocarcinoma SMMC-7721 cells cultured in vitro were treated with ferrofluid containing Fe(2)O(3) nanoparticles and irradiated with an alternating radio frequency magnetic field. The influence of the treatment on the cells was examined by inverted microscopy, MTT and flow cytometry. To study the therapeutic mechanism of the Fe(2)O(3) MFH, Hsp70, Bax, Bcl-2 and p53 were detected by immunocytochemistry and reverse transcription polymerase chain reaction (RT-PCR). It was shown that Fe(2)O(3) MFH could cause cellular necrosis, induce cellular apoptosis, and significantly inhibit cellular growth, all of which appeared to be dependent on the concentration of the Fe(2)O(3) nanoparticles. Immunocytochemistry results showed that MFH could induce high expression of Hsp70 and Bax, decrease the expression of mutant p53, and had little effect on Bcl-2. RT-PCR indicated that Hsp70 expression was high in the early stage of MFH (<24 h) and became low or absent after 24 h of MFH treatment. It can be concluded that Fe(2)O(3) MFH significantly inhibited the proliferation of in vitro cultured liver cancer cells (SMMC-7721), induced cell apoptosis and arrested the cell cycle at the G(2)/M phase. Fe(2)O(3) MFH can induce high Hsp70 expression at an early stage, enhance the expression of Bax, and decrease the expression of mutant p53, which promotes the apoptosis of tumor cells.