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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Adhesion molecules, a family of cell-surface molecules, are likely to be of central importance in mediating cell-extracellular matrix and specific cell-cell interactions within both neoplastic and inflammatory sites. The recently discovered expression of adhesion molecules on glioma cells, tumor-infiltrating lymphocytes, and endothelial cells within the tumor offers insight into the molecular basis of the interactions both between the glioma cell and surrounding heterologous cell types within the tumor environment, and between the tumor cell and the extracellular matrix. Such interactions suggest that these molecules may play roles in the homing of immune cells to these tumors and in regulating the extent of local tumor invasion. The ability to modulate adhesion molecule expression on either immune cells or their respective ligands on gliomas provides an approach to modify cell-cell interactions that may be used to increase tumor kill by the immune system. A similar approach in the modulation of adhesion molecules involved in tumor cell adhesion to the extracellular matrix or endothelial cells may be a method to limit local invasion in these lesions.
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PMID:Adhesion molecules and malignant gliomas: implications for tumorigenesis. 156 41

Adhesion of the neuronal cell surface to its underlying substrate plays an important role in neurite outgrowth in vitro. I have investigated the adhesive basis for neurite outgrowth in the presence of cytochalasin D, a disruptor of actin-containing microfilaments, and in the presence of vinblastine, a depolymerizer of microtubules. Scanning electron microscopy shows that cytochalasin D does not alter the branching configuration of filopodia on a laminin substrate, although processes are shorter and tapered distally in the presence of the drug. Using a standard attachment assay for the neuroblastoma x glioma cell line (NG108-15) I show that vinblastine does not influence attachment of NG108-15 cells to either plastic or laminin. Cytochalasin D-treated cells normally attach to high concentrations of a laminin substrate (20 micrograms/ml). However, when cell are seeded on a laminin substrate at lower concentrations (0.001-10 micrograms/ml), or on YIGSR, a fragment of laminin, cytochalasin D increases cell attachment. Cytochalasin D increases attachment in a dose-dependent manner when cells are seeded on plain polystyrene plastic, so that the number of cells attached to plastic in 1 microM cytochalasin D is similar to the number attached to laminin (20 micrograms/ml). Combining low concentrations of cytochalasin D and laminin results in greater attachment than with either agent alone. Mild trypsinization of the cell surface reduces the CD-enhanced attachment to plastic, indicating that a protein on the cell surface may be involved. The effect of cytochalasin D appears to be cell specific since cytochalasin D does not affect the attachment of a fibroblast cell line (NIH 3T3) to laminin and plastic.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of cytochalasin D on the adhesion of a neuroblastoma x glioma cell line (NG108-15) to laminin and plastic substrates. 237 8

Cell-substratum adhesion strengths have been quantified using fibroblasts and glioma cells binding to two extracellular matrix proteins, fibronectin and tenascin. A centrifugal force-based adhesion assay was used for the adhesive strength measurements, and the corresponding morphology of the adhesions was visualized by interference reflection microscopy. The initial adhesions as measured at 4 degrees C were on the order of 10(-5)dynes/cell and did not involve the cytoskeleton. Adhesion to fibronectin after 15 min at 37 degrees C were more than an order of magnitude stronger; the strengthening response required cytoskeletal involvement. By contrast to the marked strengthening of adhesion to FN, adhesion to TN was unchanged or weakened after 15 min at 37 degrees C. The absolute strength of adhesion achieved varied according to protein and cell type. When a mixed substratum of fibronectin and tenascin was tested, the presence of tenascin was found to reduce the level of the strengthening of cell adhesion normally observed at 37 degrees C on a substratum of fibronectin alone. Parallel analysis of corresponding interference reflection micrographs showed that differences in the area of cell surface within 10-15 nm of the substratum correlated closely with each of the changes in adhesion observed: after incubation for 15 min on fibronectin at 37 degrees C, glioma cells increased their surface area within close contact to the substrate by integral to 125-fold. Cells on tenascin did not increase their surface area of contact. The increased surface area of contact and the inhibitory activity of cytochalasin b suggest that the adhesive "strengthening" in the 15 min after initial binding brings additional adhesion molecules into the adhesive site and couples the actin cytoskeleton to the adhesion complex.
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PMID:Cell adhesion to fibronectin and tenascin: quantitative measurements of initial binding and subsequent strengthening response. 247 81

Adhesion studies were carried out to determine the relative ability of glioma cells and ovary-derived teratoma cells to adhere to endothelial cells obtained from mouse brain capillaries (designated MBE cell line) or mouse ovaries (designated MOE cell line). The teratoma cells showed preferential adhesion to MOE cells, whereas the glioma cells showed preferential adhesion to the MBE cell line. In contrast, the glioma and teratoma cells adhered equally to L929 and 3T3 fibroblasts. A testicular teratoma with ovary-seeking properties in vivo also adhered preferentially to MOE cells, while the preference for MBE cells was shared by glioma cells with an endothelioma and a bladder tumor line. The endothelioma, interestingly, showed a marked preferential adhesion to 3T3 cells, thus distinguishing it from the glioma. The experiments demonstrate that capillary endothelial cells derived from different sources are not alike and that differences expressed at the cell surface of these cells can be distinguished by tumor cells.
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PMID:Differential adhesion of tumor cells to capillary endothelial cells in vitro. 659 84

Adhesion of eight cell lines, derived from human gliomas of different histological types, to fibronectin, collagen I, vitronectin, and laminin was investigated in vitro. The glioma cell lines were found to attach to these substrates to different extents. Interestingly, all cell lines strongly attached to laminin. In addition, glioma cell adhesion was found to be dose dependent. Moreover, adhesion of three cell lines to fibronectin and collagen I was partially inhibited and to vitronectin completely prevented by GRGDTP peptide, indicating the involvement of integrin receptors in glioma cell adhesion. We have demonstrated, recently, that gangliosides play an important role in promoting glioma cell invasion of the reconstituted basement membrane, Matrigel, in vitro. In order to study the mechanism of action of gangliosides in this process, the role of six gangliosides (GM1, GM3, GD3, GD1a, GD1b, and GT1b) in cell adhesion to the four proteins was investigated in three cell lines. Although all gangliosides, with the exception of GM3, were found to enhance cell adhesion to these proteins to different extents, GD3 proved to be the most effective adhesion-promoting ganglioside in all three cell lines. GM3 was found to inhibit cell adhesion to the four proteins in one cell line but enhanced cell adhesion in two other cell lines. The three cell lines were found to express both GD3 and gangliosides recognised by the A2B5 antibody. Furthermore, adhesion of the three cell lines to fibronectin, vitronectin, laminin, and collagen I was inhibited by incubation with A2B5, demonstrating the involvement of intrinsic cell membrane gangliosides in adhesion of glioma cells to these proteins. Taken together with the observation that gangliosides modulate integrin receptor function, these data suggest that gangliosides may play a central role in the control of the adhesive and invasive properties of human glioma cells.
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PMID:Adhesion of human glioma cell lines to fibronectin, laminin, vitronectin and collagen I is modulated by gangliosides in vitro. 774 20

A unique characteristic of astrocytic malignancies is their frequent dissemination through the brain. Cellular determinants of migration include adhesion to the substratum, restructuring of the actin cytoskeleton to generate motion, and (in the setting of invasion into tissue) secretion of enzymes for remodeling interstitial space to accommodate forward motion of the migrating cell. In order to better understand these features in the context of local brain invasion by astrocytoma cells, the adhesion and migratory properties of these cells have been investigated in an in vitro monolayer system. Adhesion of 8 different astrocytoma cell lines to different purified human extracellular matrix (ECM) proteins (collagen type IV, cellular fibronectin, laminin, and vitronectin) revealed that there is no "astrocytoma-specific" ECM protein that consistently leads to high cell binding. Similarly, migration of astrocytoma cells was found to be variable and dependent on different ECM proteins. Laminin was frequently the most permissive for adhesion and migration. Adhesion to collagen, fibronectin, and vitronectin was integrin dependent and could be blocked using anti-beta 1 integrin antibodies; in contrast, attachment to laminin could not be blocked using these antibodies. A comparison of adhesion with migration for each of the cell lines on each of the 4 ECM proteins revealed that poor adhesion was associated with minimal migration and that frequently, high adhesion was correlated with rapid migration. When tested for migration on autologous, cell-derived ECM, none of the cell lines were as migratory as they were on one of the purified ECM proteins, with the exception of SF767 cells. Furthermore, it was found that ECM from SF767 cells promoted the migration of other astrocytoma cells. The results from this study indicate that migration is a constitutive behavior of glioma cells which is dependent on, or modified by, the presence or absence of permissive ligands in the environment.
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PMID:Determinants of human astrocytoma migration. 803 13

Recent studies of spinal cord development and plasticity, in chick, have demonstrated a loss of regenerative ability correlating to embryonic day (E) 13 of the 21-day developmental period. Here we describe membrane fractions from embryonic chick spinal cords as permissive or restrictive substrates for the neuron-like differentiation of neuroblastoma x glioma hybrid NG108-15 cells, in vitro. Plasma membranes were purified from the thoracic spinal cord of embryos at a series of developmental stages (E10-E18). Micro-well plates were coated with the fractions and NG108-15 cells cultured thereon. Cells adhered to the E10-coated wells and began to differentiate after 2 h, becoming highly differentiated, with neurites 2-3 times longer than the diameter of the cell body after 24 h in in culture. In contrast, cells cultured in E18-coated wells remained as clusters of undifferentiated cells of rounded morphology, even after 48 h in culture. As well, the permissive and restrictive plasma membranes were assessed semiquantitatively as the number of adhering cells after 20 h of culture. Adhesion of cells to the substrate decreased as the embryonic age of the plasma membrane substrate increased. Examination of the plasma membrane fractions, using SDS-PAGE, revealed several proteins in the 40-60 kDa range that varied substantially between E12, E14 and E18. Results of this study provide in vitro confirmation of previous in vivo findings; namely, that early embryonic spinal cord is initially permissive for neuritic outgrowth becoming restrictive around E13.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Developmental transition by spinal cord plasma membranes of embryonic chick from permissive to restrictive substrates for the morphological differentiation of neuroblastoma x glioma hybrid NG108-15 cell. 845 60

We have investigated the effect of integrin antibodies to a well-characterized alpha 5 beta 1 (fibronectin receptor) and to a multi-specific alpha 3 beta 1 (laminin, collagen, and fibronectin receptor), on the expression of matrix metalloproteases and the invasion ability of two human glioblastoma cell lines, SNB19 and U251. Cell adhesion assays indicated that both cell lines adhere to fibronectin, type IV collagen and laminin. Adhesion of cells to fibronectin was inhibited by a RGD peptide. Cells treated with anti-alpha 3 beta 1 or anti-alpha 5 beta 1 antibodies expressed increased levels of MMP-2. An in vitro matrigel assay also showed that the alpha 3 beta 1 antibody-treated cells had greater invasive ability than the controls. Immunofluorescence data showed that glioma cells treated with either anti-alpha 3 beta 1 or anti-alpha 5 beta 1 antibodies expressed diminished alpha 3 beta-1 and alpha 5 beta 1 integrins relative to the controls. The data show that treatment of cells with alpha 3 beta 1 antibody diminishes the integrin expression on the cell surface and increases the MMP-2 activity and invasiveness.
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PMID:Modulation of matrix metalloprotease-2 and invasion in human glioma cells by alpha 3 beta 1 integrin. 863 58

Tenascin, an extracellular matrix protein, is expressed in human gliomas in vitro and in vivo. The distribution of tenascin at the invasive edge of these tumors, even surrounding solitary invading cells, suggests a role for this protein as a regulator of glioma cell migration. We tested whether purified tenascin, passively deposited on surfaces, influenced the adhesion or migration of a human gliomaderived cell line, SF-767. Adhesion of glioma cells to tenascin increased in a dose-dependent fashion up to a coating concentration of 10 micrograms/ml. Higher coating concentrations resulted in progressively fewer cells attaching. Cell adhesion could be blocked to basal levels using anti-beta 1 integrin antibodies. In contrast, when anti-alpha v antibodies were added to the medium of cells on tenascin, cell adhesion was enhanced slightly. Using a microliter scale migration assay, we found that cell motility on tenascin was dose dependently stimulated at coating concentrations of 1 and 3 micrograms/ml, but migration was inhibited below levels of non-specific motility when tested at coating concentrations of 30 and 100 micrograms/ml. Migration on permissive concentrations of tenascin could be reversibly inhibited with anti-beta 1, while treatment with anti-alpha v antibodies increased migration rates. We conclude that SF-767 glioma cells express two separate integrin receptors that mediate contrasting adhesive and migratory responses to tenascin.
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PMID:Contrasting migratory response of astrocytoma cells to tenascin mediated by different integrins. 885 12

Glycosyltransferase gene transfection into cell lines has been an approach used successfully to elucidate the functional role of cell surface glycoconjugates. We have transfected the rat CMP-NeuAc:Galbeta1,4GlcNAc alpha2,6-sialyltransferase (EC 2.4.99.1) gene into a human, tumorigenic, glioma cell line, U373 MG. This transfection led to a marked inhibition of invasivity, alterations in adhesivity to fibronectin and collagen matrices, and inappropriately sialylated alpha3beta1 integrin. Adhesion-mediated protein tyrosine phosphorylation was reduced in the transfectants despite increased expression of focal adhesion kinase, p125fak. Furthermore, the transfectants showed a distinct cell morphology, an increased number of focal adhesion sites, and different sensitivity to cytochalasin D treatment than control U373 MG cells. These results suggest that inappropriate sialylation of cell surface glycoconjugates, such as integrins, can change focal adhesion as well as adhesion-mediated signal transduction and block glioma cell invasivity in vitro.
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PMID:alpha2,6-Sialyltransferase gene transfection into a human glioma cell line (U373 MG) results in decreased invasivity. 916 54


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