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51.
Thandokuhle Khumalo Eloise Ferreira Katarina Jovanovic Rob B. Veale Stefan F. T. Weiss 《PloS one》2015,10(10)
Cancer is a global burden due to high incidence and mortality rates and is ranked the second most diagnosed disease amongst non-communicable diseases in South Africa. A high expression level of the 37kDa/67kDa laminin receptor (LRP/LR) is one characteristic of cancer cells. This receptor is implicated in the pathogenesis of cancer cells by supporting tumor angiogenesis, metastasis and especially for this study, the evasion of apoptosis. In the current study, the role of LRP/LR on cellular viability of breast MCF-7, MDA-MB 231 and WHCO1 oesophageal cancer cells was investigated. Western blot analysis revealed that total LRP expression levels of MCF-7, MDA-MB 231 and WHCO1 were significantly downregulated by targeting LRP mRNA using siRNA-LAMR1. This knockdown of LRP/LR resulted in a significant decrease of viability in the breast and oesophageal cancer cells as determined by an MTT assay. Transfection of MDA-MB 231 cells with esiRNA-RPSA directed against a different region of the LRP mRNA had similar effects on LRP/LR expression and cell viability compared to siRNA-LAMR1, excluding an off-target effect of siRNA-LAMR1. This reduction in cellular viability is as a consequence of apoptosis induction as indicated by the exposure of the phosphatidylserine protein on the surface of breast MCF-7, MDA-MB 231 and oesophageal WHCO1 cancer cells, respectively, detected by an Annexin-V/FITC assay as well as nuclear morphological changes observed post-staining with Hoechst. These observations indicate that LRP/LR is crucial for the maintenance of cellular viability of breast and oesophageal cancer cells and recommend siRNA technology targeting LRP expression as a possible novel alternative technique for breast and oesophageal cancer treatment. 相似文献
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Mirjana Dimitrijević Stanislava Stanojević Katarina Mitić Nataša Kuštrimović Vesna Vujić Tatjana Miletić Vesna Kovačević-Jovanović 《Regulatory peptides》2010,159(1-3):100-109
It has been acknowledged that aging exerts detrimental effects on cells of the innate immune system and that neuropeptides, including neuropeptide Y (NPY) and NPY-related peptides fine-tune the activity of these cells through a receptor specific mechanism. The present study investigated the age-dependent potential of peptide YY (PYY) to modulate different granulocyte functions. The PYY reduced the carrageenan-elicited granulocyte accumulation into the air-pouch of aged (24 months) rats, and markedly decreased the phagocytosis of zymosan, as well as the H2O2 production, when applied in vivo (20 μg/air-pouch). The anti-inflammatory effect of PYY was less prominent in adult (8 months) and young (3 months) rats. However, the proportions of granulocytes expressing Y1, Y2 and Y5 receptor subtypes were significantly lower in both aged and young rats when compared to adult rats. Furthermore, the aging was found to be associated with the diminished dipeptidyl peptidase 4 (DP4, an enzyme converting the NPY and PYY to Y2/Y5 receptor selective agonists) activity in plasma. In conclusion, the diverse age-related anti-inflammatory effect of PYY in rats originates from different expression levels of Y1, Y2, and Y5 receptor subtypes in addition to different plasma DP4 activity. 相似文献
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The cytoskeleton is the physical and biochemical interface for a large variety of cellular processes. Its complex regulation machinery is involved upstream and downstream in various signaling pathways. The cytoskeleton determines the mechanical properties of a cell. Thus, cell elasticity could serve as a parameter reflecting the behavior of the system rather than reflecting the specific properties of isolated components. In this study, we used atomic force microscopy to perform real-time monitoring of cell elasticity unveiling cytoskeletal dynamics of living bronchial epithelial cells. In resting cells, we found a periodic activity of the cytoskeleton. Amplitude and frequency of this spontaneous oscillation were strongly affected by intracellular calcium. Experiments reveal that basal cell elasticity and superimposed elasticity oscillations are caused by the collective action of myosin motor proteins. We characterized the cell as a mechanically multilayered structure, and followed cytoskeletal dynamics in the different layers with high time resolution. In conclusion, the collective activities of the myosin motor proteins define overall mechanical cell dynamics, reflecting specific changes of the chemical and mechanical environment. 相似文献
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The cadmium hyperaccumulator Thlaspi praecox Wulfen (Brassicaceae) can accumulate unusually high amounts of Cd (>1,000 μg g?1 dry weight) in its seeds without drastically affecting seed viability. As embryonic tissues are the most sensitive to Cd toxicity, the aim of this study was to investigate the Cd coordination and ligand environment in seeds of field collected T. praecox using extended X-ray absorption fine structure (EXAFS), and to compare the Cd ligand environment to that in the vegetative tissues of the plant. In intact seeds and isolated embryos, almost two thirds of the Cd ligands were thiol groups (Cd-S-C-). In addition, there was coordination to phosphate groups via bridging oxygens (Cd-O-P-), as for phytate, although this ligand was not observed in the vegetative organs and tissues. In roots and shoots up to 80% of the Cd ligands were oxygen ligands that are provided by the cell walls and by organic acids stored in vacuoles. In leaf epidermis only a slightly higher percentage of oxygen ligands was detected, as compared to the mesophyll, making vacuolar compartmentation and binding to the cell walls the main detoxification mechanisms in both of these leaf tissues. 相似文献
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Katarina Almehed Szabolcs Hetényi Claes Ohlsson Hans Carlsten Helena Forsblad-d'Elia 《Arthritis research & therapy》2010,12(4):1-7