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AIM: To explore the differences in the effects of 2 representative hypoxia models on human breast cancer MDA-MB-231 cells. METHODS: To establish a chemical hypoxia model, MDA-MB-231 cells were treated with CoCl2 at different concentrations (0~300 μmol/L) for different time (24 h, 48 h and 72 h). On the other hand, MDA-MB-231 cells were exposed to hypoxia with different volume fractions (1%, 2% and 5%) of oxygen for different time (4 h, 16 h and 24 h) to establish a physical hypoxia model. The viability of the cells in the 2 hypoxia models was measured by CCK-8 assay. The protein levels of hypoxia-inducible factor-1α (HIF-1α), Bcl-2 and matrix metalloproteinase-2 (MMP-2) were determined by Western blot. The apoptosis of the cells was analyzed by flow cytometry. The cell invasion and migration were examined by Transwell assay and wound-healing assay, respectively. RESULTS: The HIF-1α was expressed in time- and dose-dependent manners. These results indicated that treatment of MDA-MB-231 cells with CoCl2 at 100 μmol/L for 24 h served as the final chemical hypoxia model, and exposure of MDA-MB-231 cells to hypoxia with 2% oxygen for 24 h served as the final physical hypoxia model. Compared with the cells with chemical hypoxia, the protein le-vel of HIF-1α was significantly increased in the cells with physical hypoxia. In addition, reoxygenation from hypoxia caused a rapidly degraded HIF-1α expression level in physical hypoxia model. Flow cytometry results showed that apoptosis was increased and the protein expression level of anti-apoptotic Bcl-2 was decreased in the cells with physical hypoxia, while no significant change was observed in the cells with chemical hypoxia. The protein expression level of MMP-2 in both hypoxia models was increased, and the invasion and migration capabilities of the cells with chemical hypoxia were enhanced. CONCLUSION: Two hypoxia models were successfully constructed. There were differences in the expression and stability of HIF-1α protein, and the viability, apoptosis, invasion and migration of the cells in the 2 different hypoxia models, which provide references for the selection of hypoxia models and the further study of characteristics of tumor cells in hypoxia environment. 相似文献
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AIM: To explore whether miR-21 low expression enhances the effect of matrine (MAT) on the apoptosis of hepatocellular carcinoma cells.METHODS: Real-time fluorescence quantitative PCR (RT-qPCR) was used to detect the expression of miR-21 in the HepG2 cells treated with different concentrations of MAT. The effect of miR-21 on MAT-induced HepG2 cell apoptosis was analyzed by flow cytometry. The mRNA and protein expression of Bcl-2 and Bax in the HepG2 cells treated with MAT was determined by RT-qPCR and Western blot.RESULTS: The expression of miR-21 increased with the increasing concentration of MAT. Low expression of miR-21 promoted MAT-induced apoptosis, and enhanced the expression of Bax at mRNA and protein levels (P<0.05), while inhibited the expression of Bcl-2 at mRNA and protein levels (P<0.05).CONCLUSION: Low expression of miR-21 enhances MAT-induced HepG2 cell apoptosis by inhibiting the expression of Bcl-2 and promoting Bax expression. 相似文献
905.
CAO Cheng-zhang HU Shu-qiao LAI Hai-yin CHEN Meng-jun SHI Yu-zhen WU Jian 《园艺学报》2017,33(10):1845-1851
AIM: To investigate the inhibitory effect of allicin on human esophageal cancer cell line EC109 and its possible mechanism by comparison with chemotherapeutic drugs. METHODS: The EC109 cells were treated with different concentrations of allicin, 5-fluorouracil and cisplatin. The cell viability was detected by CCK8 assay and the activity of lactic dehydrogenase (LDH) was analyzed at 6 h, 12 h, 24 h, 48 h and 72 h. The apoptosis of the EC109 cells induced by Z-VAD-FMK, allicin, allicin+Z-VAD-FMK, 5-fluorouracil and cisplatin was analyzed by flow cytometry with Annexin V-FITC and PI double staining. The enzyme activity changes of caspase-3, caspase-8 and caspase-9 were detected by spectrophotometry. RESULTS: Allicin had inhibitory effect on the growth of the EC109 cells and killed them in concentration-dependent and time-dependent manners. LDH activity was decreased compared with 5-fluorouracil and cisplatin. The increased activity of caspase-3 and caspase-8 in allicin-treated cells was statistically significant, but caspase-9 activity changed without statistical significance. CONCLUSION: Allicin inhibits the growth of EC109 cells in concentration-and time-dependent manners through extrinsic apoptosis pathways activated by caspase-8, and the side effects are weaker compared with 5-fluorouracil and cisplatin. 相似文献
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XIAO Ming_kui YAN Tao WANG Yao_wei LAI Ming 《保鲜与加工》1999,(5):117-121
The research on seismic response spectra of Elastic-Plastic structures has gained a lot of useful results with the development of the research on seismic response of elastic-plastic structures.This paper discusses the various kinds of elastic-plastic response spectra and points out the key problem which must be solved for their use in seismic design. 相似文献
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从绿洲农区光、温角度入手,比较分析了绿洲与非绿洲农区的光、热资源的耦合效应及其棉花的生态适应性。结果表明:绿洲棉区之所以成为优质棉区,是因为采取的栽培技术使绿洲地区的光、热富能期与高效结铃期耦合的结果,用栽培技术协调了生物与环境间的良好关系,从而确保了绿洲棉产业的迅速发展。 相似文献
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