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Microwaves are non-ionizing radiation of a frequency range between 300 MHz ~ 300 GHz, are widely used in areas such as radar, aerospace, communications, industrial and medical. In recent years, with the frequency of 2450 MHz Household microwave applications, and frequency range of 800 ~ 1800 MHz spread of mobile phones, it is exposed to microwave radiation, the opportunity to significantly increase, the public has begun to focus may produce the biological effects of exposure to microwave radiation and its impact on health. The biological effects of microwave two types: thermal effects and non-thermal effects, generation of non-thermal and thermal effects of microwave frequency, power density, pulse modulation. More reported in the literature on the thermal effects of microwave radiation higher than the absorption rate (specific absorption rate, SAR) is relatively small, and the coverage of non-thermal effects. In this study, the use of different strength 2450MHz microwave irradiation of nasopharyngeal carcinoma cells some time to explore microwave human nasopharyngeal carcinoma cell morphology, cell proliferation and apoptosis, with a view to understanding cancer cell apoptosis induced by microwave molecular mechanisms and clinical treatment provided a theoretical basis. Research content and results: 1. Observation different power density microwave irradiation of microwave radiation on the proliferation of human nasopharyngeal carcinoma cell survival and cell proliferation cycle. With the increase in the density of microwave power, human nasopharyngeal carcinoma cell viability decreased gradually 10mW/cm 2 group survival compared with the control group decreased slightly, no significant difference between the two sex; 20mW/cm 2 with 30mW/cm of 2 group survival rates were 76.75%, 65.07%, and the two groups and the control group, there are differences (P <0.01); two groups with 10mW/cm 2 were also compared differences (P <0.01); microwave radiation can cause human nasopharyngeal carcinoma cell survival rates were lower. With the increase in the dose of microwave, cell cycle G 1 phase cells significantly increased S phase and G 2 phase cells gradually reduce the number of 20mW/cm < / sup> group and 30mW/cm 2 group appeared sub G 1 peak number of two groups of apoptotic cells increased with the increase in the intensity of the microwave, S the phase cells reduce the number of cells to enter the S phase of DNA synthesis to reduce. 2. Changes in cell morphology and apoptosis detection microwave irradiation microwave irradiation light microscope, cells were observed immediately, the three groups showed no obvious morphological changes, cultured for 24 h, 10mW/cm 2 group visible cell edge blur, a small number of cells off the wall. 20mW/cm 2 group most off the wall, a small number of cell structure is unclear, and the visible part of the cell debris. 30mW/cm 2 group off the wall, fuzzy cell structure, cell debris increased significantly. Electron microscopy 10mW/cm 2 group mainly irreversible damage, part of the expansion of the endoplasmic reticulum, the intracellular vacuolization and myelin-like structure formation, mitochondrial swelling, but the nuclear membrane is clear; 20mW / cm 2 group a few cells appear vacuolar degeneration, the cells most of the performance of early apoptotic changes, chromatin condensation, margination cells; 30mW/cm 2 can be seen most apoptosis and a small number of cell degeneration, typical apoptotic cells, chromatin condensation and cohesion around the nuclear membrane, showing crescent-shaped, narrow cell body, the structural integrity of the organelle. TUNEL method the microwave irradiation descendants nasopharyngeal carcinoma cell apoptosis change. Cells during apoptosis, chromatin DNA strand breaks. Damage detection of human nasopharyngeal carcinoma cell DNA duplexes positive cells was significantly increased terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TdT-mediated dUTP nick end labeling method, TUNEL method) based on this principle. 3. Microwave radiation on cells MDA content and SOD activity affect 10mW/cm 2 group after irradiation, superoxide dismutase (superoxide dismutase, SOD) activity, malondialdehyde (Malondialdehyde , MDA) content in a slight increase in the control group had no significant difference (P> 0.05); 20mW/cm 2 group and 30mW/cm 2 group after irradiation SOD activity decreased significantly, MDA content increased significantly, the two groups were compared with the control group, a significant difference (P <0.05), and downward trend with the increase of the intensity of the microwave, SOD activity, MDA content upward trend. Conclusion: 1. Microwave irradiation can inhibit the proliferation of human nasopharyngeal carcinoma cells, inhibition of cell cycle. 2. Microwave irradiation can affect the morphology of the human nasopharyngeal carcinoma cells to promote the formation of apoptotic bodies, promote apoptosis. 3. Microwave irradiation can cause nasopharyngeal cancer cell line MDA content was significantly higher SOD activity decreased.
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