Safe alternative cancer therapy using electromagnetic fields

Cross-talk between non-ionizing electromagnetic fields and metastasis; EMT and hybrid E/M may explain the anticancer role of EMFs

Recent studies have shown that non-ionizing electromagnetic fields (NIEMFs) in a specific frequency, intensity, and exposure time can have anti-cancer effects on various cancer cells; however, the underlying precise mechanism of action is not transparent. Most cancer deaths are due to metastasis. This important phenomenon plays an inevitable role in different steps of cancer including progression and development. It has different stages including invasion, intravasation, migration, extravasation, and homing. Epithelial-mesenchymal transition (EMT), as well as hybrid E/M state, are biological processes, that involve both natural embryogenesis and tissue regeneration, and abnormal conditions including organ fibrosis or metastasis. In this context, some evidence reveals possible footprints of the important EMT-related pathways which may be affected in different EMFs treatments. In this article, critical EMT molecules and/or pathways which can be potentially affected by EMFs (e.g., VEGFR, ROS, P53, PI3K/AKT, MAPK, Cyclin B1, and NF-кB) are discussed to shed light on the mechanism of EMFs anti-cancer effect.

In Vitro Carcinoma Treatment Using Magnetic Nanocarriers under Ultrasound and Magnetic Fields

Nowadays, tumor hypoxia has become a more predominant problem for diagnosis as well as treatment of cancer due to difficulties in delivering chemotherapeutic drugs and their carriers to these regions with reduced vasculature and oxygen supply. In such cases, external physical stimulus-mediated drug delivery, such as ultrasound and magnetic fields, would be effective. In this work, the effect of simultaneous exposure of low-intensity pulsed ultrasound and static magnetic field on colon (HCT116) and hepatocellular (HepG2) carcinoma cell inhibition was assessed in vitro. The treatment, in the presence of anticancer drug, with and without magnetic carrier, significantly increased the reactive oxygen species production and hyperpolarized the cancer cells. As a result, a significant increase in cell inhibition, up to 86%, was observed compared to 50% inhibition with bare anticancer drug. The treatment appears to have relatively more effect on HepG2 cells during the initial 24 h than on HCT116 cells. The proposed treatment was also found to reduce cancer cell necrosis and did not show any inhibitory effect on healthy cells (MC3T3). Our in vitro results suggest that this approach has strong application potential to treat cancer at lower drug dosage to achieve similar inhibition and can reduce health risks associated with drugs.

Effects of pulsed electromagnetic fields on postmenopausal osteoporosis

Postmenopausal osteoporosis (PMOP) is considered to be a well-defined subject that has caused high morbidity and mortality. In elderly women diagnosed with PMOP, low bone mass and fragile bone strength have been proven to significantly increase risk of fragility fractures. Currently, various anabolic and anti-resorptive therapies have been employed in an attempt to retain healthy bone mass and strength. Pulsed electromagnetic fields (PEMFs), first applied in treating patients with delayed fracture healing and nonunions, may turn out to be another potential and effective therapy for PMOP. PEMFs can enhance osteoblastogenesis and inhibit osteoclastogenesis, thus contributing to an increase in bone mass and strength. However, accurate mechanisms of the positive effects of PEMFs on PMOP remain to be further elucidated. This review attempts to summarize recent advances of PEMFs in treating PMOP based on clinical trials, and animal and cellular studies. Possible mechanisms are also introduced, and the future possibility of application of PEMFs on PMOP are further explored and discussed. Bioelectromagnetics. 38:406-424, 2017. © 2017 Wiley Periodicals, Inc.

Lucifer Yellow uptake by CHO cells exposed to magnetic and electric pulses

BACKGROUND

The cell membrane acts as a barrier that hinders free entrance of most hydrophilic molecules into the cell. Due to numerous applications in medicine, biology and biotechnology, the introduction of impermeant molecules into biological cells has drawn considerable attention in the past years. One of the most famous methods in this field is electroporation, in which electric pulses with high intensity and short duration are applied to the cells. The aim of our study was to investigate the effect of time-varying magnetic field with different parameters on transmembrane molecular transport.

MATERIALS AND METHODS

'Moreover, a comparison was made between the uptake results due to magnetic pulse exposure and electroporation mediated uptake.' at the end of Background part. The Chinese hamster ovary (CHO) cells were exposed to magnetic pulses of 2.2 T peak strength and 250 μs duration delivered by Magstim stimulator and double 70 mm coil. Three different frequencies of 0.25, 1 and 10 Hz pulses with 112, 56 and 28 number of pulses were applied (altogether nine experimental groups) and Lucifer Yellow uptake was measured in each group. Moreover, maximum uptake of Lucifer Yellow obtained by magnetic pulses was compared to the measured uptake due to electroporation with typical parameters of 8 pulses of 100 μs, repetition frequency of 1 Hz and electric field intensities of 200 to 600 V/cm.

RESULTS AND CONCLUSIONS

Our results show that time-varying magnetic field exposure increases transmembrane molecular transport and this uptake is greater for lower frequencies and larger number of pulses. Besides, the comparison shows that electroporation is more effective than pulsed magnetic field, but the observed uptake enhancement due to magnetic exposure is still considerable.

Effects of exposure to static magnetic fields (0.2-0.4 T) on the growth and adhesion of tumor cells

AIM: To investigate the effects of exposure to moderate-intensity static magnetic fields on the growth and adhesion of tumor cells.

METHODS: After SMMC-7721, HepG2 and MCF-7 cells were exposed to static magnetic fields (0.2-0.4 T), cell growth was measured by methyl thiazol tetrazolium (MTT) assay, cell adhesion to fibronectin (FN) was detected by crystal violet staining, and cell cycle distribution was evaluated by flow cytometry.

RESULTS: The effects of exposure to static magnetic fields on different cell types differed greatly. Moderate-intensity static magnetic field exposure did not affect cell growth, but reduced cell adhesion to FN (1.847 ± 0.342 vs 1.094 ± 0.33, P = 0.012) and decreased the percentage of cells in G2/M phase (12.05 ± 1.14 vs 3.74 ± 0.87, P = 0.018) in SMMC-7721 cells. In MCF-7 cells, moderate-intensity static magnetic field exposure promoted cell growth, enhanced cell adhesion to FN (1.094 ± 0.076 vs 2.177 ± 0.474, P = 0.017) and increased the percentage of cells in G2/M phase (4.42% ± 1.23% vs 12.04% ± 1.65%, P = 0.004). In HepG2 cells, cell growth was inhibited and cell cycle was blocked in G2 phase (0.305 ± 0.076 vs 0.394 ± 0.089, P = 0.467) after exposure to moderate-intensity static magnetic fields though cell adhesion to FN was not significantly altered (1.90% ± 0.79% vs 0.24% ± 0.15%, P = 0.046).

CONCLUSION: Exposure to moderate-intensity static magnetic fields (0.2-0.4 T) exerts different effects on cell growth, adhesion and cell cycle progression in different types of tumor cells.

Inhibitory effects of a gradient static magnetic field on normal angiogenesis

Angiogenesis, the formation of new blood vessels, is critical in many normal and pathological processes such as development, reproduction, tumor growth, and metastasis. Recently, exposure to moderate-intensity static magnetic fields (1 mT to 1 T) has attracted much attention for its potential therapeutic value as a noninvasive intervening method. Nevertheless, the effects of moderate-intensity and spatial gradient static magnetic fields (GSMF) on angiogenesis have not received enough attention. In this study, the effects of GSMF (0.2-0.4 T, 2.09 T/m, 1-11 days) on angiogenesis were investigated both in vitro and in vivo. An MTT assay was used as an in vitro method to detect the proliferation ability of human umbilical veins endothelial cells (HUVECs). Two kinds of in vivo models, a chick chorioallantoic membrane (CAM) and a matrigel plug, were used to detect the effects of GSMF on angiogenesis. The results showed that the proliferation ability of HUVECs was significantly inhibited 24 h after the onset of exposure. With regard to the CAM model, vascular numbers in the CAM that was continuously exposed to the GSMF were all less than those in normal condition. In accordance with the gross appearance, the contents of hemoglobin in the models exposed to GSMF for 7-9 days were also less. In addition, similar to the CAM model, the results of vascular density and hemoglobin contents in the matrigel plug also demonstrated that the GSMF exposure for 7 or 11 days inhibited vascularization. These findings indicate that GSMF might inhibit or prevent new blood vessels formation and could be helpful for the treatment of some diseases relevant to pathological angiogenesis.