Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1261473 (sarcoma)
 25,952 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A novel gelatin-binding 21 kDa protein was identified in the culture medium of fibroblastic and sarcoma cells by affinity chromatography on gelatin-Sepharose. Its affinity for gelatin was lower than that of the other gelatin-binding proteins, fibronectin and the 70 kDa protein, as judged by stepwise elution by urea and arginine. The protein bound also to spermine and to some extent to heparin but not to staphylococcal protein A, bovine serum albumin, concanavalin A or plain Sepharose 4B. In gel filtration chromatography the protein eluted in fractions differing from those of fibronectin and the Mr 70,000 protein and retained its ability to bind to gelatin-Sepharose, indicating that the binding was not mediated by the two other gelatin-binding proteins. It contains intrachain disulfide bridges, as judged by analysis under nonreducing and reducing conditions. The protein is composed of two major subtypes with pI values of 5.85-6.10 and 6.55-6.75. It was sensitive to trypsin but not to collagenase or thrombin. Antiserum was raised in rabbits against the gelatin-binding proteins isolated from serum-free conditioned fibroblast culture medium. The antiserum reacted with fibronectin, the Mr 70,000 protein and the Mr 21,000 protein in immunoprecipitation experiments. Absorption of the antiserum with human plasma fibronectin did not decrease its reactivity with the Mr 70,000 and 21,000 proteins. However, absorption with the Mr 70,000 protein abolished also the reactivity against the Mr 21,000 protein, suggesting immunological cross-reactivity. The protein was synthesized independently from the Mr 70,000 protein, as shown by pulse-chase labeling experiments of cells. The production of the Mr 21,000 protein in cultured cells was enhanced by transforming growth factor-beta.
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PMID:Characterization of a novel gelatin-binding 21 kDa protein secreted by cultured adherent cells. 301 29

In order to study cell translocation in vitro on a physiological substrate a novel cell migration assay was developed using the inner limiting membrane of the avian embryonic retina. The matrix sheet consists of a laminin-rich basal lamina covered by a dense layer of neuroepithelial endfeet. The retina basal lamina does not contain fibronectin. Cells translocating on this substrate displace the neuroepithelial endfeet, leaving behind tracks in the endfeet monolayer. Motility of cells and the relative forward to lateral migration can be quantitated by measuring lengths, widths, and areas of the tracks. Using this assay system, the conditions and patterns of cell migration for a variety of cells have been examined. In the absence of serum all cell types show only minor migratory activity and addition of serum to the culture medium always enhances the rate of cell migration in a saturable, dose-response manner. The serum cannot be replaced by fibronectin or vitronectin (serum spreading factor). For maximum cell migration, serum has to be constantly present in the medium; however, 58% cell migration is obtained in serum-free medium when the matrix is preincubated with serum. According to the area and linearity of the tracks, the migratory behavior of the different cells can be classified into three groups: (i) fibroblasts and the nonpigmented Bowes melanoma cells form straight and long tracks; (ii) glioma, sarcoma, and carcinoma cells from straight but short tracks, and (iii) neuronal tumor cells, epithelial cells, and pigmented B16 melanoma cells form wide and short tracks. Comparative studies with low and high metastatic clones of tumorgenic cell lines show that migratory activity and metastatic potential of cells do not necessarily correlate. Finally, we show that fibroblasts deposit fibronectin fibrils on their paths as they migrate on the basal lamina. Fibronectin trails are also seen when fibroblasts are cultured on plain basal laminae that are pretreated with detergent to remove the endfeet monolayer. Likewise, when fibroblasts are cultured in the presence of antifibronectin antibodies, the fibronectin secreted by cells is detectable. Due to antibody treatment the cellular fibronectin is precipitated and its normal fibril formation is inhibited; however, the translocation of fibroblasts is not impaired.
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PMID:Migratory behavior of cells on embryonic retina basal lamina. 305 94

Immunofluorescent examination of extracellular matrix of 5 fibrosarcomas showed the matrix to contain fibronectin and collagen type I, III, V. Fibrosarcoma matrix is characterized by the absence of collagen type IV and collagen type III predominance over type I differentiating this tumor from synovial sarcoma, neurogenic sarcoma, dermatofibrosarcoma protuberans, malignant fibrous histiocytoma. Their matrices showed the presence of type IV collagen, equal proportion of interstitial collagens or collagen type I predominance over type III typical for synovial sarcoma. The findings can be employed in practical morphologic diagnosis of soft tissue tumors.
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PMID:[Fibrosarcoma: immunohistochemical study of the extracellular matrix]. 307 48

We studied the immunocytochemical localization of urokinase-type plasminogen activator (u-PA) and the type 1 plasminogen activator inhibitor (PAI-1) in human fibroblasts and sarcoma cells, using both polyclonal and monoclonal antibodies. The u-PA was found to be located at discrete cell-substratum contact sites, and also at areas of cell-cell contacts, whereas PAI-1 was distributed as a homogeneous carpet excluding strialike areas on the substrate under the cells. To confirm the extracellular localization of u-PA and PAI-1, we stained the cells live at 0 degree C before fixation. A double-labeling experiment showed different distribution of u-PA and PAI-1 under the cells, and especially their peripheral parts. The staining pattern of u-PA and PAI-1 resisted treatment with 0.2% saponin followed by mechanical removal of cells, a method previously reported to isolate focal contact membranes of fibroblasts. We further demonstrated the deposition of u-PA to the contact areas of cells obtained by saponin treatment by zymography, and that of PAI-1 by metabolic labeling, reverse zymography, immunoblotting, and immunoprecipitation. Fibronectin was also present in the preparations. The deposition of both PAI-1 and fibronectin by the sarcoma cells was enhanced, after treating the cells with 10(-6) M dexamethasone. The confinement of u-PA to discrete contact sites and the more uniform distribution of PAI-1 on the cell substratum may explain how cells producing large amounts of enzyme inhibitors can produce PA-mediated focal proteolysis.
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PMID:Distinct localizations of urokinase-type plasminogen activator and its type 1 inhibitor under cultured human fibroblasts and sarcoma cells. 310 49

The expression of glial fibrillary acidic protein, fibronectin (FN), factor VIII-related antigen (FVIII/RAG), and of three monohistiocytic markers, lysozyme, alpha-1-antitrypsin and alpha-1-antichymotrypsin was examined in five gliosarcomas (GS) by peroxidase-antiperoxidase immunostaining of formalin-fixed and paraffin-embedded specimens, and compared with vascular changes in 16 glioblastomas (GB). In contrast to GB, endothelial proliferations of GS were sheathed by sarcomatous tissue (perivascular sarcoma), which was contiguous with fibrosarcomatous areas. Cells with conspicuous intracytoplasmic FN content (FN+ cells) were seen in the vascular stroma of GB and dominated in the sarcomatous parts of GS. Most FN+ cells of GS were of varying size and shape and clearly neoplastic. Monohistiocytic markers were demonstrable in small infiltrating mononuclear cells as well as in many sarcomatous cells including FN+ cells. FVIII/RAG was restricted to lumen-lining endothelium and was not found in sarcomatous cells. These results suggest that a major part of sarcoma in GS is less likely to develop from proliferated endothelial cells than from histiocytic cells in the perivascular spaces of GB. By FN mediation, histiocytic cells might also guide and promote sarcomatous proliferations of other mesenchymal cells, leading to fibrosarcomatous development. Prominent monstrous giant cells of one GS seemed to be degenerating glioma cells.
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PMID:Contribution of histiocytic cells to sarcomatous development of the gliosarcoma. An immunohistochemical study. 311 Nov 62

Sarcolectins are present in a great variety of tissues from mammalian origin. Such substances were observed to be secreted from cultures of human embryonic fibroblasts, human osteosarcoma and rat Rous sarcoma transformed cells and could be extracted from TG 180 Crocker Sarcoma or normal human placenta. All sarcolectins tested here, were comparable by their physicochemical properties to those previously reported in hamster or human sarcomas. Indeed, they are proteins or glycoproteins, resistant to pepsin and migrate in SDS-PAGE in the 65 kDa area. They agglutinate cells with an affinity for simple sugars and degrade previously established interferon-induced antiviral resistance. Considering the hamster sarcolectin as reference in this comparative study, both differences and similarities in the antigenic properties of mouse, rat and human sarcolectin variants were demonstrated. An indirect immunofluorescence assay showed that sarcolectins were specifically labelled on the cell surface but not detected in the cytoplasm after methanol or acetone permeabilization of the membrane. By electron microscopy, using immunoperoxidase labelling, sarcolectins can be localized on the surface of normal, transformed, human or rat cells. Only limited segments of normal cell membranes were labelled, while transformed cells were frequently stained on their whole surface. Other known extracellular proteins, such as fibronectin and collagen, did not share common antigenic determinants with sarcolectins.
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PMID:Cell distribution and antigenic properties of mammalian sarcolectins. 311 55

We have recently shown that urokinase-type plasminogen activator (u-PA) and plasminogen activator inhibitor type 1 are both found extracellularly beneath cultured human skin fibroblasts and HT-1080 sarcoma cells, but in distinct localizations. Here, the ultrastructural distribution of u-PA was studied using immunoferritin electron microscopy. In HT-1080 cells, u-PA on the extracellular aspect of the plasma membrane was detected at sites of direct contact of the cell with the growth substratum beneath all parts of the ventral cell surface. The ferritin-labeled adhesion plaques, which were enriched in submembraneous microfilaments, were frequently seen at the leading lamellae of the cells as well as in lamellipodia and microspikes. Besides the cell-substratum adhesion plaques, ferritin label was detected at cell-cell contact sites. Double-label immunofluorescence showed a striking colocalization of u-PA and vinculin in both HT-1080 cells and WI-38 lung fibroblasts, which is consistent with u-PA being a focal contact component. The u-PA-containing focal contacts of WI-38 cells had no direct codistribution with fibronectin fibrils. In WI-38 cells made stationary by cultivation in a medium containing 0.5% FCS, vinculin plaques became highly elongated and more centrally located, whereas u-PA immunolabel disappeared from such focal adhesions. These findings show that plasma membrane-associated u-PA is an intrinsic component of focal contacts, where, we propose, it enables directional proteolysis for cell migration and invasion.
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PMID:Ultrastructural localization of plasma membrane-associated urokinase-type plasminogen activator at focal contacts. 312 96

The interaction of cells with laminin and laminin fragments was studied in short-term cell attachment assays. Neurite-promoting chymotrypsin fragments of laminin were isolated using a monoclonal antibody which blocks neurite outgrowth on laminin. The fragments were shown, by electron microscopy after rotary shadowing and by immunological reactivity with different monoclonal antibodies, to contain only the distal end of the long arm. These fragments promoted the attachment and spreading of glioma, sarcoma, carcinoma, muscle, and endodermal cells to the same extent as intact laminin. The attachment was unaffected by peptides containing the RGD sequence. The morphology of the cells on the chymotrypsin fragments was indistinguishable from that on intact laminin but different from the morphology of the same cells on fibronectin. Light microscopy and scanning electron microscopy showed extensive process formation on laminin but not on fibronectin suggestive of increased cell motility in response to laminin. We conclude that the neurite-promoting domain of laminin contains a major site of interaction for non-neuronal cells and that this site induces a cellular response in certain non-neuronal cells that is unique to laminin.
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PMID:The neurite-promoting domain of human laminin promotes attachment and induces characteristic morphology in non-neuronal cells. 316 84

Single cell suspensions of early postnatal mouse cerebellum adhere to substrate-bound culture supernatants of the teratocarcinoma cell line PF-HR9 and can be inhibited to adhere by antibodies to the neural cell adhesion molecules L1 and N-CAM. Adhesion can also be inhibited by the glycosaminoglycans heparin and heparan sulfate, and less by chondroitin sulfate or hyaluronic acid. Heparinase treatment of cells, but not of HR9 substrate, reduces adhesion. Adhesion does not appear to be mediated by laminin, a constituent of HR9 extracellular matrix, since L1 and N-CAM antibodies do not interfere with cell adhesion on EHS sarcoma laminin as substrate and since antibodies to EHS sarcoma laminin partially inhibit adhesion to HR9 extracellular matrix which contains laminin. Of the other extracellular matrix constituents analysed in HR9 culture supernatants (collagen type IV, a heparan sulfate proteoglycan and fibronectin) none could be shown to promote adhesion, when coated as substrate, suggesting that yet unidentified compounds are responsible for L1- or N-CAM-mediated cell adhesion. These experiments show for the first time that extracellular matrix constituents can act as binding partners for the neural cell adhesion molecules L1 and N-CAM.
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PMID:Adhesion of neural cells to extracellular matrix constituents. Involvement of glycosaminoglycans and cell adhesion molecules. 317 50

An efficient and reliable procedure for the isolation and culture of endothelium from large vessels of small animals (e.g., rat) is described, which takes advantage of endothelial cell-extracellular matrix interactions to promote the outgrowth of cells from tissue explants. The procedure may also permit the isolation by nonenzymatic means, of endothelial cells from other vessels and tissues. Rings and opened segments of aortic tissue were placed on a variety of substrates including: untreated tissue culture plastic; films of fibronectin, laminin, type I collagen, and gelatin; gels of type I collagen (Vitrogen, Collagen Corporation, Palo Alto, California), of basement membrane components derived from the EHS sarcoma (Matrigel, Collaborative Research Inc., Lexington, Massachusetts), and of agar and agarose. The medium used was OPTI-MEM or RPMI 1640 (Gibco Laboratories, Grand Island, New York) with 3% or 20% fetal calf serum, and 50 micrograms/ml endothelial cell growth supplement. Only explants on Vitrogen and on Matrigel produced a significant and consistent outgrowth of cells and this occurred shortly after the initiation of explants. Virtually no outgrowth occurred from explants on the other substrata, even after 10 days in culture. On Vitrogen gels, the cells emerged from the explants as single stellate and bipolar cells, whereas those on Matrigel grew as chains and sheets from the edges of the explant. Cells were passaged from both types of gels onto plastic or glass surfaces. The passaged cells isolated from both gel matrices exhibited specific endothelial cell characteristics including a "cobbled" morphology at confluence, positive staining for von Willebrand factor, and uptake of Di-I-Ac-low density lipoprotein. Because rat and other small animal aortic endothelial cells are resistant to isolation by enzymatic treatment, this technique provides a simple means to obtain large numbers of this cell type. Further, the method permits study of endothelial cell functions in vitro, and the roles which the extracellular matrix may play in these processes.
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PMID:Isolation of rat aortic endothelial cells by primary explant techniques and their phenotypic modulation by defined substrata. 329 52


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