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Green fluorescent protein (GFP) gene was transfected and expressed in murine embryonic stem (ES) cells under the control of the astrocyte-specific glial fibrillary acidic protein (GFAP) promoter. Stably transfected cells were characterized by immunohistochemistry and by fluorescence microscopy. Cells containing GFP were differentiated to Type I and Type II astrocytes after induction by all-trans retinoic acid. Differentiated cells were expressed GFP and visualized by fluorescence microscopy. Differentiated cells expressed GFP were correlated with the expression of GFAP and morphological change. It demonstrates that the cell line expressed GFP can be used to trace the morphological changes of astrocytes during differentiation, and further for the isolation of astrocytes from the mixed cells differentiated from ES cell. 相似文献
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《Cell cycle (Georgetown, Tex.)》2013,12(6):1031-1036
We recently found that microRNA-34a (miR-34a) is downregulated in human glioma tumors as compared to normal brain, and that miR-34a levels in mutant-p53 gliomas were lower than in wildtype-p53 tumors. We showed that miR-34a expression in glioma and medulloblastoma cells inhibits cell proliferation, G1/S cell cycle progression, cell survival, cell migration and cell invasion, but that miR-34a expression in human astrocytes does not affect cell survival and cell cycle. We uncovered the oncogenes c-Met, Notch-1 and Notch-2 as direct targets of miR-34a that are inhibited by miR-34a transfection. We found that c-Met levels in human glioma specimens inversely correlate with miR-34a levels. We showed that c-Met and Notch partially mediate the inhibitory effects of miR-34a on cell proliferation and cell death. We also found that mir-34a expression inhibits in vivo glioma xenograft growth. We concluded that miR-34a is a potential tumor suppressor in brain tumors that acts by targeting multiple oncogenes. In this extra view, we briefly review and discuss the implications of these findings and present new data on the effects of miR-34a in glioma stem cells. The new data show that miR-34a expression inhibits various malignancy endpoints in glioma stem cells. Importantly, they also show for the first time that miR-34a expression induces glioma stem cell differentiation. Altogether, the data suggest that miR-34a is a tumor suppressor and a potential potent therapeutic agent that acts by targeting multiple oncogenic pathways in brain tumors and by inducing the differentiation of cancer stem cells. 相似文献
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Isolation murine mesenchymal stem cells by positive selection 总被引:2,自引:0,他引:2
Isolation and purification of mesenchymal stem cells (MSCs) from mouse via plastic adherent cultures is arduous because of
the unwanted growth of hematopoietic cells and non-MSCs. In this work, homogenous populations of CD34+ MSCs from mouse bone marrow were isolated via positive selection. For this purpose, C57Bl/6 mice were killed and bone marrow
cells were aspirated before incubation with magnetic bead conjugated to anti-CD34 antibody. A sample of positively selected
CD34+ cells were prepared for flow cytometry to examine the expression of CD34 antigen and others were subcultured in a 25-cm2 culture flask. To investigate the mesenchymal nature, the plastic adherent cultivated cells were induced to differentiate
along osteoblastic and adipogenic lineages. Furthermore, the expression of some surface markers was investigated by flow cytometry.
According to the result, purified populations of fibroblast-like CD34+ cells were achieved in the first passage (1 wk after culture initiation). The cells expressed CD34, CD44, Sca-1, and Vcam-1
antigens (markers) but not CD11b and CD45. They were capable of differentiating into osteocytes and adipocytes. This study
indicated that our protocol can result in the efficient isolation of homogenous populations of MSCs from C57BL/6 mouse bone
marrow. We have shown that murine bone marrow-derived CD34+ cells with plastic adherent properties and capability of differentiating into skeletal lineages in vitro are MSCs. 相似文献
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Gliomas, much like other cancers, are composed of a heterogeneous mix of neoplastic and non-neoplastic cells that include
both native and recruited cells. There is extensive diversity among the tumor cells, with differing capacity for in vitro and in vivo growth, a property intimately linked to the cell’s differentiation status. Those cells that are undifferentiated, self-renewing,
with the capacity for developing tumors (tumorigenic) cells are designated by some as cancer stem cells, because of the stem-like
properties. These cells may be a critical therapeutic target. However the exact identity and cell(s) of origin of the so-called
glioma cancer stem cell remain elusive. Here we review the current understanding of glioma cancer stem cell biology. 相似文献
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C Pallis 《BMJ (Clinical research ed.)》1982,285(6353):1487-1490
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Zhi Dai Shi-Rong Li Pei-Feng Zhu Lu Liu Bei Wang Ya-Ping Liu Xiao-Dong Luo Xu-Dong Zhao 《Bioorganic & medicinal chemistry letters》2017,27(13):2863-2867
Glioblastoma multiform (GBM) is a highly aggressive brain tumor with poor life expectancy, and glioma stem cells (GSCs) are a small population of tumor cells existed in GBM, in which GSCs response to drive GBM recurrence, invasion and contribute to the anti-cancer resistance. GSCs have been identified and developed as a therapeutic target for GBM and can be used in drugs screening. Isocostunolide is a natural sesquiterpenoid and contained abundant resource in medicinal plants, but the anti-cancer efficacies of it against GSCs are still unexplored. In this investigation, the anti-tumor activity of isocostunolide against GSCs was investigated and the result demonstrated that it inhibited the growth of GSCs (GSC-3#, GSC-12#, GSC-18#) significantly with an IC50 value of 2.80 μg/ml, 2.61 μg/ml, 1.07 μg/ml, respectively. In further mechanism study, isocostunolide inhibited GSCs cell proliferation, induced GSCs apoptosis significantly, as well as increased the proportion of the cleavage of caspase-3. The result suggested that isocostunolide induced GSCs apoptosis via the caspase dependent apoptotic pathway. Moreover, isocostunolide damaged GSCs colony formation capacity significantly and exhibited the anti-cancer efficacy against GSCs in vitro. 相似文献
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Hjelmeland AB Wu Q Heddleston JM Choudhary GS MacSwords J Lathia JD McLendon R Lindner D Sloan A Rich JN 《Cell death and differentiation》2011,18(5):829-840
Malignant gliomas are lethal cancers that display cellular hierarchies with cancer stem cells at the apex. Glioma stem cells (GSCs) are not uniformly distributed, but rather located in specialized niches, suggesting that the cancer stem cell phenotype is regulated by the tumor microenvironment. Indeed, recent studies show that hypoxia and its molecular responses regulate cancer stem cell maintenance. We now demonstrate that acidic conditions, independent of restricted oxygen, promote the expression of GSC markers, self-renewal and tumor growth. GSCs exert paracrine effects on tumor growth through elaboration of angiogenic factors, and low pH conditions augment this expression associated with induction of hypoxia inducible factor 2α (HIF2α), a GSC-specific regulator. Induction of HIF2α and other GSC markers by acidic stress can be reverted by elevating pH in vitro, suggesting that raising intratumoral pH may be beneficial for targeting the GSC phenotype. Together, our results suggest that exposure to low pH promotes malignancy through the induction of a cancer stem cell phenotype, and that culturing cancer cells at lower pH reflective of endogenous tumor conditions may better retain the cellular heterogeneity found in tumors. 相似文献
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The OR37 subfamily of odorant receptors (ORs) exists exclusively in mammals. In contrast to ORs in general, they are highly
conserved within and across species. These unique features raise the question, whether olfactory information gathered by the
OR37 sensory cells is processed in specially designated brain areas. To elucidate the wiring of projection neurons from OR37
glomeruli into higher brain areas, tracing experiments were performed. The application of DiI onto the ventral area of the
olfactory bulb, which harbors the OR37 glomeruli, led to the labeling of fibers not only in the typical olfactory cortical
regions, but also in the medial amygdala and the hypothalamus. To visualize the projections from a defined OR37 glomerulus
more precisely, transgenic mice were studied in which olfactory sensory neurons co-express the receptor subtype OR37C and
the transsynaptic tracer wheat germ agglutinin (WGA). WGA became visible not only in the OR37C sensory neurons and the corresponding
OR37C glomerulus, but also in cell somata located in the mitral/tufted cell layer adjacent to the OR37C glomerulus, indicating
a transfer of WGA onto projection neurons. In the brain, WGA immunoreactivity was not detectable in typical olfactory cortical
areas, but instead in distinct areas of the medial amygdala. Detailed mapping revealed that the WGA immunoreactivity was restricted
to the posterior-dorsal subnucleus of the medial amygdala. In addition, WGA immunoreactivity was visible in some well-circumscribed
areas of the hypothalamus. These results are indicative for a unique connectivity from OR37C sensory cells into higher brain
centers. 相似文献
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Cecilie Jonsgar Sandberg Gabriel Altschuler Jieun Jeong Kirsten Kierulf Strømme Biljana Stangeland Wayne Murrell Unn-Hilde Grasmo-Wendler Ola Myklebost Eirik Helseth Einar Osland Vik-Mo Winston Hide Iver A. Langmoen 《Experimental cell research》2013
Glioblastoma is the most common brain tumor. Median survival in unselected patients is <10 months. The tumor harbors stem-like cells that self-renew and propagate upon serial transplantation in mice, although the clinical relevance of these cells has not been well documented. We have performed the first genome-wide analysis that directly relates the gene expression profile of nine enriched populations of glioblastoma stem cells (GSCs) to five identically isolated and cultivated populations of stem cells from the normal adult human brain. Although the two cell types share common stem- and lineage-related markers, GSCs show a more heterogeneous gene expression. We identified a number of pathways that are dysregulated in GSCs. A subset of these pathways has previously been identified in leukemic stem cells, suggesting that cancer stem cells of different origin may have common features. Genes upregulated in GSCs were also highly expressed in embryonic and induced pluripotent stem cells. We found that canonical Wnt-signaling plays an important role in GSCs, but not in adult human neural stem cells. As well we identified a 30-gene signature highly overexpressed in GSCs. The expression of these signature genes correlates with clinical outcome and demonstrates the clinical relevance of GSCs. 相似文献
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Xin Wei Zhi Dai Jing Yang Afsar Khan Hao-Fei Yu Yun-Li Zhao Yi-Fen Wang Ya-Ping Liu Zi-Feng Yang Wan-Yi Huang Xin-Hua Wang Xu-Dong Zhao Xiao-Dong Luo 《Bioorganic & medicinal chemistry》2018,26(8):1776-1783
Unlike reported bisindoles linked by single bond directly, alstoniasidines A (1) and B (2), from Alstonia scholaris featuring unprecedented skeleton with two indole moieties bridged by a sugar, represented a novel bisindole type having strictosamide-glucopyranose-picraline scaffold. Both compounds exhibited selective cytotoxicity against human glioma stem cells (GSCs) and induced caspase-3 dependent extrinsic apoptosis by increasing the expression of interleukin 1 (IL-1), tumor necrosis factor (TNF-α), and the cleaved caspase-3, while damaged the unlimited proliferation and self-renewal capacity of GSCs. This finding might provide new type of leads for the selective killing of human glioma stem cells. 相似文献
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M W Frohlich 《Stain technology》1986,61(3):139-143
In the standard polarizing microscope, birefringent material appears bright only if its optic axis is oblique to the axes of the polarizer and analyzer filters; consequently, an object may be visualized as several disconnected bright regions. This confusing appearance is avoided if the crossed plane polarizers of the conventional microscope are replaced by circular polarizers of opposite handedness. All orientations of the optic axis in the focal plane then become equivalent; objects generally appear uniformly bright. Ordinary microscopes are easily modified to use this technic with readily available components. 相似文献
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The coprodeum is a very efficient Na+-retaining epithelium. Coprodeum from birds on a high Na+ diet has virtually no ion transport, while an Amiloride-sensitive Na+ absorption of 10–12 μ equiv·cm?2·h?1 is induced in the coprodeal epithelium from birds on a low Na+ diet. Both measurements of the Na+ influx and Na+-diffusion potentials across the luminal cell membrane have revealed a selective opening of this membrane to Na+ in birds on a low Na+ diet. Freeze-fracture P faces of the luminal membrane in coprodea taken from birds on a low Na+ diet have rod-shaped particles, , in more than 20% of the principal cells. Rod-shaped particles appear in less than 1% of these cells in coprodea from high Na+-diet birds. Thus a low Na+ diet induces rod-shaped particles in the luminal cell membrane of the hen coprodeum. These new particles may function as Na+-channels mediating the increased Na+-influx across the apical cell membrane. 相似文献
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目的:研究亚硒酸钠对人脑胶质瘤干细胞的生长抑制效应及细胞内活性氧的影响。方法:使用不同浓度的亚硒酸钠(0.5μmol/L、1.5μmol/L、3.0μmol/L)对人脑胶质瘤干细胞进行侵染,分别通过四甲基偶氮唑盐(MTT)比色法及荧光检测仪检测亚硒酸钠对人脑胶质瘤干细胞的增殖及活性氧(ROS)含量的影响。结果:亚硒酸钠对人脑胶质瘤干细胞具有明显的抑制作用,且随亚硒酸钠浓度的增加对人脑胶质瘤干细胞细胞生长抑制作用逐渐加强。结论:亚硒酸钠能抑制人脑胶质瘤干细胞的生长,并可增加其细胞内ROS的含量。 相似文献
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