共查询到20条相似文献,搜索用时 78 毫秒
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Martha J. Somerman Janice E. Berry Zhila Khalkhali-Ellis Philip Osdoby Robert U. Simpson 《Experimental cell research》1995,216(2)
HL-60 cells, a promyelocytic leukemic cell line, provide a good model for studying the role of adhesion molecules and associated receptors involved in cell differentiation. When exposed to factors such as phorbol esters, these cells grown in suspension differentiate into monocytes and adhere to tissue culture dishes. In this study we showed that HL-60 cells exposed to phorbol esters express osteopontin (OPN), a cell adhesion molecule linked with osteoclast function. Moreover, the timed expression of OPN, in phorbol ester treated cells, was linked to increased cell adhesion. Subsequent to the expression of OPN, an increase in mRNA levels for αV integrin subunit was observed. The αVβ3 integrin, a cell surface receptor found in high concentrations in osteoclasts, is considered to be a receptor for OPN. Furthermore, during differentiation we detected an increase in two cell surface markers specific for osteoclasts, 75B and 121F. This is the first report to demonstrate expression of OPN during differentiation of HL-60 cells, indicating that HL-60 cells can be used as a tool to enhance our understanding as to the role of OPN in cell differentiation. 相似文献
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Hui-Jun Zhu F. Patrick Ross Xu Cao Steven L. Teitelbaum 《Journal of cellular biochemistry》1996,61(3):420-429
1,25-Dihydroxyvitamin D3 (1,25(OH)2D3) transactivates the avian β3 integrin gene whose promoter contains at least two vitamin D response elements, one of which is in close proximity to a candidate AP1 site (TGACTCA). Since fos/jun and steroid hormones interact to regulate gene expression, we asked whether phorbol-12-myristate-13-acetate (PMA), which stimulates binding of fos/jun to AP1 sites, transactivates the avian β3 integrin gene and, if so, does the phorbol ester modulate 1,25(OH)2D3 induction of the gene. We find the candidate AP1 sequence comigrates with the consensus AP1 sequence on electromobility shift assay when incubated with recombinant c-jun protein. Furthermore, PMA prompts expression of β3 integrin mRNA in the avian monocytic line, HD11. The increase in message reflects transactivation of the β3 gene and is mirrored by plasma membrane appearance of the integrin heterodimer αvβ3. Moreover, attesting to the functional significance of PMA-enhanced αvβ3 expression, cells treated with concentrations of the phorbol ester that induce the β3 gene, spread extensively on plastic, an event blocked by an anti-αv antibody and a peptide mimetic known to inhibit αvβ3-mediated cell attachment. Interestingly, co-addition of 1.25(OH)2D3 and PMA prompts greater expression of αvβ3 than when the cells are exposed to either agent alone and PMA enhances 1,25(OH)2D3-induced β3 integrin mRNA expression. Thus, PMA and 1,25(OH)2D3 impact on the avian β3 integrin gene independently and in combination. © 1996 Wiley-Liss, Inc. 相似文献
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Zou C Song G Luo Q Yuan L Yang L 《In vitro cellular & developmental biology. Animal》2011,47(3):241-250
Mesenchymal stem cells (MSCs) are characterized by their ability of self-renewal paired with the capacity to differentiate into multiple mesenchymal cell lineages. Numerous studies have reported beneficial effects of MSCs in tissue repair and regeneration. After in vivo administration, MSCs home to and engraft to injured tissues. However, the molecular mechanisms are not clear. Osteopontin (OPN) has been found to be elevated in response to injury and inflammation and its role on cell mobilization has been studied. Therefore, the facts imply that OPN may contribute to the recruitment of MSCs to the sites of injury. In this study, using transwell assay, we found that rat bone marrow-derived mesenchymal stem cells (rMSCs) migrated towards OPN in a concentration-dependent manner. To further examine the involved molecular mechanisms for OPN-induced rMSCs migration, RT-PCR, and Western blot were used to detect the expressions of integrin β1 and CD44v6, the two receptors of OPN. OPN promoted integrin β1 mRNA and protein expression while CD44v6 mRNA level was not altered. Blockade of integrin β1 also inhibited OPN-induced rMSCs migration, indicating the possible involvement of integrin β1 in OPN-induced migration in rMSCs. Our data have shown for the first time that OPN increases integrin β1 expression in rMSCs and promotes rMSCs migration through the ligation to integrin β1. 相似文献
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Neda Mazaheri Maryam Peymani Hamid Galehdari Kamran Ghaedi Ali Ghoochani Abbas Kiani-Esfahani Mohammad Hossein Nasr-Esfahani 《Cellular and molecular neurobiology》2018,38(4):891-899
Recently our group used oligodendrocyte progenitor cells (OPCs) as appropriate model cells to pinpoint the mechanism of the progress of neurodegenerative disorders. In the present study, we focused on the therapeutic role of osteopontin (OPN), a secreted glycosylated phosphoprotein, involved in a number of physiological events including bone formation and remodeling, immune responses, and tumor progression. Protective role of OPN, as a negative regulator of tumorigenesis, has already been clarified. Human embryonic stem cell-derived OPCs were pretreated with OPN before induction of apoptosis by H2O2. Data indicated that OPN prohibited cell death and enhanced OPC viability. This effect is achieved through reduction of apoptosis and induction of anti-apoptosis markers. In addition OPN induces expression of several integrin subunits, responsible for OPN interaction. Notably, our findings showed that expression of αV β1/β3/β5 and β8 integrins increased in response to OPN, while treatment with H2O2 down-regulated αV β1/β5 and β8 integrins expression significantly. In conclusion, OPN may act via αV integrin signaling and trigger suppression of P53-dependent apoptotic cascades. Therefore OPN therapy may be considered as a feasible process to prevent progress of neurodegenerative diseases in human. 相似文献
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《Neurochemistry international》2010,56(8):826-832
We and others have shown that focal cerebral ischemia induces lateral migration of neuroblasts from the ipsilateral subventricular zone (SVZ) to the ischemic striatum. The signaling pathways underlying this phenomenon are not fully understood. The present study examined the role of osteopontin (OPN) in post-ischemic lateral migration of neuroblasts. Focal ischemia was induced by transient middle cerebral artery occlusion in adult spontaneous hypertensive rats. The expression of OPN in the ischemic brain was evaluated by immunohistochemistry, which showed that an up-regulation of OPN expression in the ipsilateral striatum at day 3, 7, 14 and 1 month of reperfusion with a peak at day 7. Double staining showed co-localization of OPN with ED1+ macrophages/microglia in the ischemic regions. Inhibition of OPN activity by infusing a neutralizing antibody against OPN into the ischemic striatum significantly decreased the area covered with doublecortin+ neuroblasts in the ipsilateral striatum. In vitro, OPN treatment did not affect the proliferation of neural progenitors, but induced an increased trans-well and radial migration of neural progenitors. The cultured neural progenitors expressed the OPN receptors CD44 and integrin β1. Blockade of the CD44 receptor had no effects on OPN mediated trans-well and radial migration of neural progenitors. However, blockade of integrin β1 receptor abolished the migration of neural progenitors in the absence or the presence of OPN. These results suggest that up-regulated expression of OPN produced by macrophages/microglia in the ischemic brain is an attractant and inducer for the lateral migration of neuroblasts from the SVZ to the injured region. 相似文献
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Osteopontin (OPN) is a multifunctional protein participating in the regulation of different Th cell lineages and critically involved in the initiation of immune responses to diverse pathogens. Our study goal was to verify whether OPN helps modulate the protective Th1 and Th17 cytokine responses in C57BL/6 mice infected with Trypanosoma cruzi, the etiological agent of Chagas disease. Parasite infection induced OPN release from murine macrophages in vitro and acute Chagas mice displayed enhanced serum levels of this cytokine at the peak of parasitemia. Upon administration of a neutralizing anti-OPN antibody, recently infected mice presented lower Th1 and Th17 responses, increased parasitemia and succumbed earlier and at higher rates to infection than non-immune IgG-receiving controls. The anti-OPN therapy also resulted in reduced circulating levels of IL-12 p70, IFN-γ, IL-17A and specific IgG2a antibodies. Furthermore, antibody-mediated blockade of OPN activity abrogated the ex vivo production of IL-12 p70, IFN-γ and IL-17A, while promoting IL-10 secretion, by spleen macrophages and CD4+ T cells from T. cruzi-infected mice. Th1 and Th17 cytokine release induced by OPN preferentially involved the αvβ3 integrin OPN receptor, whereas concomitant down-modulation of IL-10 production would mostly depend on OPN interaction with CD44. Our findings suggest that, in resistant C57BL/6 mice, elicitation of protective Th1 and Th17 cytokine responses to T. cruzi infection is likely to be regulated by endogenous OPN. 相似文献
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Chieh-Hsi Wu Adrienne Frostholm Angel L. De Blas Andrej Rotter 《Journal of neurochemistry》1995,65(3):1229-1239
Abstract: The γ-aminobutyric acidA (GABAA)/benzodiazepine (BZ) receptor is a pentamer composed of subunits belonging to several classes (α1–6, β1–4, γ1–4, δ, and ρ1 and ρ2). In situ hybridization, radioligand autoradiography, and immunocytochemistry were used to examine GABAA/BZ receptor α1, α6, β2, β3, and γ2 subunit expression in murine Purkinje, granule, and deep cerebellar neurons after in vivo ethanol exposure. Chronic ethanol treatment resulted in decreased α1 subunit mRNA expression in each cell type, whereas the expression of α6 and γ2 subunit mRNA levels increased; no changes were observed in the expression of β2 and β3 subunit mRNA. GABA and BZ agonist binding and antibody staining paralleled the changes in mRNA levels. Acute ethanol injection resulted in increased expression of α1 and β3 mRNAs, whereas levels of α6, β2, and γ2 mRNAs remained stable. Our results indicate that, in cerebellar neurons, the expression of specific GABAA/BZ receptor subunit mRNAs, polypeptides, and binding sites is independently regulated by in vivo administration of alcohol. The observed changes were not restricted to any one cerebellar cell type, because subunit expression in Purkinje, granule, and deep cerebellar cells was similarly affected. 相似文献
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目的:探讨CD44变异亚型对急性白血病细胞增殖和迁移的影响。方法:选择对数生长期的急性白血病细胞株HL-60、THP-1和慢性白血病细胞株K562,采用荧光定量PCR法检测CD44v6mRNA的表达。通过电转的方法转染CD44v6siRNA到HL-60和THP-1细胞抑制细胞的CD44v6表达,通过western方法检测CD44v6蛋白的抑制情况。将实验分成HL-60+N-siRNA、HL-60+CD44V6-siRNA、THP-1+N-si RNA、THP-1+CD44V6-siRNA共4组,培养24、48、72 h后分别取细胞悬液用台盼蓝染色后计数活细胞数检测细胞的增殖情况;使用Transwell小室培养法观察HL-60和THP-1细胞的迁移率。结果:通过荧光定量PCR方法检测THP-1和HL-60细胞均高表达CD44v6(分别为0.0037±0.0007和0.00292±0.0002),明显高于K562的表达(P0.01);转染后的HL-60和THP-1细胞株中CD44v6蛋白表达水平明显下调,细胞计数结果显示转染CD44v6-siRNA的HL-60和THP-1细胞在24、48和72 h增殖均明显下降。迁移实验结果显示THP-1+N-si RNA和HL-60+N-si RNA细胞的迁移率为17%和23%,与相应对照组相比THP-1+CD44v6-siRNA和HL60+CD44v6-siRNA组细胞24 h迁移率明显下降(分别降至11%和14%)。结论:CD44v6可以通过干预白血病细胞的增殖和迁移能力,参与调解白血病细胞的增殖和髓外进展。 相似文献
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We studied the effects of differentiation-inducers on the integrin profile and adhesive properties of K562 leukemia cells. The fibronectin (Fn) receptor integrin, α5β1, was the only integrin expressed in suspension cultured K562 cells. When the cells were exposed to 12-O-tetradecanoylphorbol-13-acetate (TPA) immunoreactivity for the β1 integrin subunit was slightly enhanced. TPA exposure also induced the appearance of the α2, α3, αv and β3 integrin subunits, but the platelet integrin subunit αIIb was not detected. On the other hand, hemin chloride-induced erythroid differentiation of K562 cells diminished the expression of the α5β1 integrin on the surface of the cells. Adhesion experiments with TPA-exposed K562 cells indicated that although the adherence to the extracellular matrix (ECM) proteins as a rule was low a few cells spread on these proteins. The present results specify the effects of differentiation inducers on the integrin profile of K562 cells and excludes the comprehension that TPA would induce expression of the platelet integrin αIIb on their surface. Our results also show, that an increased expression of a certain integrin does not necessarily lead to a comparable adhesion ability on its ligand in vitro. 相似文献
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CD157/BST-1 is expressed on mature myeloid cells but not on their precursors in vivo. Also CD38, a homologous gene to CD157, is upregulated in promyelocytic HL-60 cells by the monocyte and granulocyte differentiation-inducing 1alpha,25dihydroxyvitamin D3 (VD3) and all-trans retinoic acid (ATRA), respectively. We have examined whether CD157 expression is upregulated when the promyeloid HL-60 and/or U937 cells are induced to differentiate into mature phenotypes in vitro. VD3 treatment irreversibly upregulated the expression of CD157 in HL-60 cells but not in U937 cells in a time- and concentration-dependent manner when analyzed by flow cytometry, immunoblotting and/or RT-PCR. Different monocyte and granulocyte lineage inducers induced CD157 expression to varying extents while the macrophage differentiation-inducing phorbol 12-myristate 13-acetate (PMA) induced its down-regulation. Time-kinetics of VD3 treatment of HL-60 cells showed that the appearance of CD157 and CD11b (a differentiation marker) antigens were not substantial up to 24 hours but increased subsequently although the appearance of CD38 became significant within 6 hours. Two-color staining of VD3-treated HL-60 cells displayed an apparently linear correlation between CD157 and CD11b expression. Dibutyryl cAMP (cAMP agonist) and forskolin (cAMP-increasing agent) augmented the VD3-dependent induction of CD157 and CD11b expression while PGE1 (cAMP-decreasing agent) inhibited it, suggesting the involvement of a cAMP-dependent mechanism in VD3-induced CD157 upregulation. Co-treatment of HL-60 cells with VD3 plus TNF-alpha or ara-C produced an additive effect on CD157 upregulation. The upregulated CD157 in the VD3-differentiated HL-60 cells was able to activate CD157-dependent tyrosine kinase signal when cross-linked with anti-CD157 antibody. 相似文献
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R. Sadej J. Spychala A. C. Skladanowski 《Nucleosides, nucleotides & nucleic acids》2013,32(9-11):1119-1123
Upregulated expression of eN has been found in the highly invasive human melanoma cell lines but neither in melanocytes nor in primary tumor cells. Membrane proteins associated with cell adhesion and metastasis: α5-, β1-, β3-integrins, and CD44 were elevated gradually in accordance with increasing metastatic potential. αv-integrin was seen mostly in aggressive melanomas. The expression of eN correlated with a number of metastasis-related markers and thus may have a function in the process. eN activity went parallel with its amount in all cells. Concanavalin A strongly inhibited the enzyme in a noncompetitive way. Clustering of eN protein in overexpressing cells by ConA-treatment increased the enzyme association with the heavy cytoskeletal complexes. A similar shift towards cytoskeletal fractions took also place with other membrane proteins coexpressed with eN. This ConA-induced association may reflect a putative interaction of eN with physiological ligand, that upon interaction, aggregates protein components of lipid rafts and triggers signaling pathway that may be intrinsically involved in cell-stroma adhesion. 相似文献
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Cynthia M. Davis Susan C. Danehower Antonio Laurenza J. Leslie Molony 《Journal of cellular biochemistry》1993,51(2):206-218
When cultured on a basement membrane substratum, endothelial cells undergo a rapid series of morphological and functional changes which result in the formation of histotypic tube-like structures, a process which mimics in vivo angiogenesis. Since this process is probably dependent on several cell adhesion and cell signaling phenomena, we examined the roles of integrins and protein kinase C in endothelial cell cord formation. Polyclonal antisera directed against the entire vitronectin (αvβ3) and fibronectin (α5β1) receptors inhibited cord formation. Subunit-specific monoclonal antibodies to αv, β3, and β1 integrin subunits inhibited cord formation, while monoclonal antibodies to α3 did not, which implicated the vitronectin receptor, and not the fibronectin receptor, in vascular formation. Protein kinase C inhibitors inhibited cord formation, while phorbol 12-myristate 13-acetate (PMA) caused endothelial cells to form longer cords. Since the vitronectin receptor has been shown to be phosphorylated in an in vitro system by protein kinase C, the possible functional link between the vitronectin receptor and protein kinase C during cellular morphogenesis was examined. The vitronectin receptor was more highly phosphorylated in cord-forming endothelial cells on basement membrane than in monolayer cells on vitronectin. Furthermore, this phosphorylation was inhibited by protein kinase C inhibitors, and PMA was required to induce vitronectin receptor phosphorylation in endothelial cells cultured on vitronectin. Colocalization studies were also performed using antisera to the vitronectin receptor and antibodies to protein kinase C. Although no strict colocalization was found, protein kinase C was localized in the cytoskeleton of endothelial cells initially plated on basement membrane or on vitronectin, and it translocated to the plasma membrane of C-shaped cord-forming cells on basement membrane. Thus, both the vitronectin receptor and protein kinase C play a role in in vitro cord formation. © 1993 Wiley-Liss, Inc. 相似文献
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Marcelina E. Kremser Małgorzata Przybyło Dorota Hoja-Łukowicz Ewa Pocheć Angela Amoresano Andrea Carpentieri Monika Bubka Anna Lityńska 《Biochimica et Biophysica Acta (BBA)/General Subjects》2008
It is well documented that glycan synthesis is altered in some pathological processes, including cancer. The most frequently observed alterations during tumourigenesis are extensive expression of β1,6-branched complex type N-glycans, the presence of poly-N-acetyllactosamine structures, and high sialylation of cell surface glycoproteins. This study investigated two integrins, α3β1 and αvβ3, whose expression is closely related to cancer progression. Their oligosaccharide structures in two metastatic melanoma cell lines (WM9, WM239) were analysed with the use of matrix-assisted laser desorption ionisation mass spectrometry. Both examined integrins possessed heavily sialylated and fucosylated glycans, with β1,6-branches and short polylactosamine chains. In WM9 cells, α3β1 integrin was more variously glycosylated than αvβ3; in WM239 cells the situation was the reverse. Functional studies (wound healing and ELISA integrin binding assays) revealed that the N-oligosaccharide component of the tested integrins influenced melanoma cell migration on vitronectin and α3β1 integrin binding to laminin-5. Additionally, more variously glycosylated integrins exerted a stronger influence on these parameters. To the best of our knowledge, this is the first report concerning structural characterisation of αvβ3 integrin glycans in melanoma or in any cancer cells. 相似文献