This study aimed to investigate the therapeutic mechanism of treating SMMC-7721 liver cancer cells with magnetic fluid hyperthermia (MFH) using Fe2O3 nanoparticles. Hepatocarcinoma SMMC-7721 cells cultured in vitro were treated with ferrofluid containing Fe2O3 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 Fe2O3 MFH, Hsp70, Bax, Bcl-2 and p53 were detected by immunocytochemistry and reverse transcription polymerase chain reaction (RT-PCR). It was shown that Fe2O3 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 Fe2O3 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 Fe2O3 MFH significantly inhibited the proliferation of in vitro cultured liver cancer cells (SMMC-7721), induced cell apoptosis and arrested the cell cycle at the G2/M phase. Fe2O3 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.

Copper does not exist in a free state within cells but is found consistently bound to metalloproteins. Specific metallochaperones escort copper to numerous targets within the cell, providing protection from the toxic effects of intracellular free copper. Many metallochaperones have been characterized in yeast, mouse, and human. To further characterize mouse metallochaperones, we cloned murine Ccsd from an adult mouse cDNA brain library, including both the coding region and the 5′ and 3′ UTRs. We obtained a 1,174-bp cDNA with an 825-bp open reading frame, translating a 274 amino acid protein that is 86.9% identical to human CCS. Using a mouse × hamster radiation hybrid panel, we mapped Ccsd to a proximal position on mouse chromosome 19. We mapped human CCS to 11q13 (homologous with mouse chromosome 19), utilizing a human × hamster radiation hybrid panel. The human and mouse metallochaperones are ubiquitously expressed in the major tissues of the body but seem to have different transcription products.