Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001511 (Adhesion)
 5,955 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Adhesion of tumor cells (TC) to endothelial cells (EC) is necessary for movement of TC out of the interstitium to form metastatic deposits. This interaction may be influenced by proadhesive molecules such as lipoxygenase products of arachidonic acid metabolism. We studied the effect of inflammatory stimuli, A23187 calcium ionophore, n-formyl-methionyl-leucine-phenylalanine (FMLP) and phorbol myristate acetate (PMA) on TC-EC interaction. Adherence of metastatic breast tumor cell line (MCF-7), choriocarcinoma cell line (JEG-3), and non metastatic pituitary cell (GH-3) were assayed as the number of radiolabeled TC attached to EC (cpm/well). TC and EC were incubated with A23187, FMLP, and PMA for varying time periods. Lipoxygenase products (LTB4, 5-HETE) were measured under basal and stimulated conditions using RP-HPLC and RIA. There were no differences in basal adherence of TC lines to EC. When EC were incubated with stimuli, there were significant increases in the numbers of MCF-7 and JEG-3 cells adherent to EC compared to GH-3. Light and phase contrast microscopy confirmed that TC were attached to EC. Upon stimulation, GH-3 preferentially produced prostaglandins (PGI1(2)) while MCF-7 and JEG-3 produced lipoxygenase products (LTB4 and 5-HETE). Pre-incubation of MCF-7 and JEG-3 with the lipoxygenase inhibitor nordihydroguiaretic acid resulted in partial inhibition of adhesion to EC. Our data strongly indicate a role for lipoxygenase products of arachidonic acid in adherence of TC to EC.
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PMID:Tumor cell-endothelial cell interactions: evidence for roles for lipoxygenase products of arachidonic acid in metastasis. 915 Mar 75

Mast cells are known to adhere to laminin, although there is limited information on the characteristics of this event. To further examine this adhesive interaction, we thus determined the adherence of murine mast cell lines and primary bone marrow cultured mast cells (BMCMC) to murine laminin (mLN), human placental laminin-1 (hLN), merosin (laminin-2) and various laminin fragments, concentrating on activating stimuli, the involvement of integrins, and the effect on mast cell activation. Murine mast cells were found to adhere to both mLN and hLN and to merosin, not only following exposure to phorbol 12-myristate 13-acetate (PMA), but also after Fc epsilon RI aggregation or addition of stem cell factor (SCF). Adhesion to laminin was partially inhibited by soluble E8 and PA22-2, both fragments of laminin that promote mast-cell adhesion when bound on surfaces. Mast-cell lines and BMCMC consistently expressed high levels of alpha 6 integrin. Antibody to alpha 6 blocked spontaneous and inhibited activated mast-cell adhesion to hLN, and inhibited mast-cell adhesion to mLN and its fragment E8. Mast-cell adhesion to both laminin isoforms increased Fc epsilon RI-mediated mast-cell secretion. These observations demonstrate that mast-cell attachment to laminin is promoted by physiological stimuli, is mediated principally by alpha 6 integrin, and results in enhanced cell activation.
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PMID:Characterization of adhesive interactions between mast cells and laminin isoforms: evidence of a principal role for alpha 6 integrin. 949 98

T cell activation rapidly and transiently regulates the functional activity of integrin receptors. Stimulation of CD3/T cell receptor, CD2 or CD28, as well as activation with phorbol esters, can induce within minutes an increase in beta1 integrin-mediated adhesion of T cells to fibronectin. In this study, we have produced and utilized a mutant of the Jurkat T cell line, designated A1, that lacks protein and mRNA expression of the beta1 integrin subunit but retains normal levels of CD2, CD3, and CD28 on the cell surface. Activation-dependent adhesion of A1 cells to fibronectin could be restored upon transfection of a wild-type human beta1 integrin cDNA. Adhesion induced by phorbol 12-myristate 13-acetate-, CD3-, CD2-, and CD28 stimulation did not occur if the carboxy-terminal five amino acids of the beta1 tail were truncated or if either of two well-conserved NPXY motifs were deleted. Scanning alanine substitutions of the carboxy-terminal five amino acids demonstrated a critical role for the tyrosine residue at position 795. The carboxy-terminal truncation and the NPXY deletions also reduced adhesion induced by direct stimulation of the beta1 integrin with the activating beta1 integrin-specific mAb TS2/16, although the effects were not as dramatic as observed with the other integrin-activating signals. These results demonstrate a vital role for the amino-terminal NPXY motif and the carboxy-terminal end of the beta1 integrin cytoplasmic domain in activation-dependent regulation of integrin-mediated adhesion in T cells. Furthermore, the A1 cell line represents a valuable new cellular reagent for the analysis of beta1 integrin structure and function in human T cells.
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PMID:Use of a beta1 integrin-deficient human T cell to identify beta1 integrin cytoplasmic domain sequences critical for integrin function. 976 39

Early in inflammation, adhesion occurs between leukocytes and endothelium when selectins bind to sialyl Lewis X (sLex) and related oligosaccharides. We tested novel compounds that mimic sLex for their ability to inhibit selectin-mediated adhesion of human eosinophils and neutrophils in vitro. Neutrophils and eosinophils were isolated by density gradient centrifugation, and eosinophils were further purified by immunomagnetic negative selection. Adhesion to unstimulated or interleukin-1beta-stimulated (5 ng/ml, 4-6 h) umbilical vein endothelial monolayers was tested under static or rotating conditions, where adhesion is primarily E- or L-selectin dependent, respectively. P-selectin-dependent adhesion was tested on immobilized platelets treated with or without phorbol myristate acetate (10(-7) M, 10 min). Stimulus-induced adhesion was always at least 4-fold higher than without stimulus, and selectin dependence was confirmed with specific blocking monoclonal antibodies. E-selectin-dependent adhesion of eosinophils and neutrophils was inhibited by compound GM2296 (the concentration producing 50% inhibition of adhesion [IC50] approximately 0.5-1 mM). E-selectin-dependent adhesion of neutrophils, but not eosinophils, was also inhibited by another compound, sLex with a lipid tail (30 +/- 6% inhibition at 3 mM), whereas compound GM1292 slightly inhibited adhesion of both (23 +/- 5 and 20 +/- 6% inhibition, respectively, at 1 mM). L-selectin-dependent adhesion was more effectively inhibited by GM2296 (IC50 approximately 0.2-0.5 mM), although P-selectin-dependent adhesion was also inhibited (IC50 approximately 1 mM). Inhibition was reversible without affecting viability, and no effect was seen with these compounds in assays testing neutrophil adhesion to immobilized intercellular adhesion molecule-1. Thus, compound GM2296, a carbon-fucosylated derivative of glycyrrhetinic acid, inhibits E-, L-, and P-selectin-dependent eosinophil and neutrophil adhesion. The ability of these and perhaps other related glycomimetic compounds to interfere with the function of more than one type of selectin makes them desirable candidates as anti-inflammatory agents.
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PMID:Antagonism of selectin-dependent adhesion of human eosinophils and neutrophils by glycomimetics and oligosaccharide compounds. 980 49

Because oleic acid is implicated in the antiatherogenic effects attributed to the Mediterranean diet, we investigated whether this fatty acid can modulate endothelial activation, ie, the concerted expression of gene products involved in leukocyte recruitment and early atherogenesis. We incubated sodium oleate with human umbilical vein endothelial cells for 0 to 72 hours, followed by coincubation of oleate with human recombinant tumor necrosis factor, interleukin (IL)-1alpha, IL-1beta, IL-4, Escherichia coli lipopolysaccharide (LPS), or phorbol 12-myristate 13-acetate for a further 6 to 24 hours. The endothelial expression of vascular cell adhesion molecule-1 (VCAM-1), E-selectin, and intercellular adhesion molecule-1 was monitored by cell surface enzyme immunoassays or flow cytometry, and steady-state levels of VCAM-1 mRNA were assessed by Northern blot analysis. At 10 to 100 micromol/L for >24 hours, oleate inhibited the expression of all adhesion molecules tested. After a 72-hour incubation with oleate and a further 16-hour incubation with oleate plus 1 microg/mL LPS, VCAM-1 expression was reduced by >40% compared with control. Adhesion of monocytoid U937 cells to LPS-treated endothelial cells was reduced concomitantly. Oleate also produced a quantitatively similar reduction of VCAM-1 mRNA levels on Northern blot analysis and inhibited nuclear factor-kappaB activation on electrophoretic mobility shift assays. Incubation of endothelial cells with oleate for 72 hours decreased the relative proportions of saturated (palmitic and stearic) acids in total cell lipids and increased the proportions of oleate in total cell lipids without significantly changing the relative proportions of polyunsaturated fatty acids. Although less potent than polyunsaturated fatty acids in inhibiting endothelial activation, oleic acid may contribute to the prevention of atherogenesis through selective displacement of saturated fatty acids in cell membrane phospholipids and a consequent modulation of gene expression for molecules involved in monocyte recruitment.
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PMID:Oleic acid inhibits endothelial activation : A direct vascular antiatherogenic mechanism of a nutritional component in the mediterranean diet. 997 1

Adhesion of fibroblasts to extracellular matrices via integrin receptors is accompanied by extensive cytoskeletal rearrangements and intracellular signaling events. The protein kinase C (PKC) family of serine/threonine kinases has been implicated in several integrin-mediated events including focal adhesion formation, cell spreading, cell migration, and cytoskeletal rearrangements. However, the mechanism by which PKC regulates integrin function is not known. To characterize the role of PKC family kinases in mediating integrin-induced signaling, we monitored the effects of PKC inhibition on fibronectin-induced signaling events in Cos7 cells using pharmacological and genetic approaches. We found that inhibition of classical and novel isoforms of PKC by down-regulation with 12-0-tetradeconoyl-phorbol-13-acetate or overexpression of dominant-negative mutants of PKC significantly reduced extracellular regulated kinase 2 (Erk2) activation by fibronectin receptors in Cos7 cells. Furthermore, overexpression of constitutively active PKCalpha, PKCdelta, or PKCepsilon was sufficient to rescue 12-0-tetradeconoyl-phorbol-13-acetate-mediated down-regulation of Erk2 activation, and all three of these PKC isoforms were activated following adhesion. PKC was required for maximal activation of mitogen-activated kinase kinase 1, Raf-1, and Ras, tyrosine phosphorylation of Shc, and Shc association with Grb2. PKC inhibition does not appear to have a generalized effect on integrin signaling, because it does not block integrin-induced focal adhesion kinase or paxillin tyrosine phosphorylation. These results indicate that PKC activity enhances Erk2 activation in response to fibronectin by stimulating the Erk/mitogen-activated protein kinase pathway at an early step upstream of Shc.
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PMID:Protein kinase C regulates integrin-induced activation of the extracellular regulated kinase pathway upstream of Shc. 1018 52

Adhesion is associated with tyrosine phosphorylation in many types of cells. Although macrophages are known to adhere and phagocytose foreign particles, the signal transduction pathway of macrophages in response to adhesion to the foreign substrate has not been fully investigated. In the present study we investigated tyrosine-phosphorylated proteins and phosphorylation of paxillin in alveolar macrophages (AMs) following adhesion to a plastic substrate. Adhesion to a plastic dish resulted in tyrosine phosphorylation of a 68 000 MW protein, which was shown, by immunoprecipitation and immunoblotting in the present study, to be a rat Syk kinase. Treatment with erbstatin reduced both tyrosine phosphorylation of Syk and adherence of AMs, while treatment with cytochalasin B inhibited spreading of AMs but did not inhibit tyrosine phosphorylation of Syk. These results suggest that tyrosine phosphorylation of Syk plays an important role in adhesion of AMs to the plastic substrate, but not in AM spreading. Paxillin is known to be tyrosine phosphorylated following adhesion to the extracellular matrix in many types of cells. However, paxillin appeared to be serine/threonine phosphorylated rather than tyrosine phosphorylated following adhesion of AMs to the plastic substrate. Treatment with A23187 (a calcium ionophore), but not phorbol 12-myristate 13-acetate (PMA; a protein kinase C stimulator), induced tyrosine phosphorylation of Syk in non-adherent AMs. Treatment with either A23187 or PMA caused electromobility changes of paxillin that were mainly a result of serine/threonine phosphorylation. These results suggest that adhesion to the plastic substrate leads to two differently regulated events in AMs: tyrosine phosphorylation of Syk and serine/threonine phosphorylation of paxillin, both of which are probably mediated by an increase in intracellular calcium.
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PMID:Syk and paxillin are differentially phosphorylated following adhesion to the plastic substrate in rat alveolar macrophages. 1044 62

Adhesion of metastatic human mammary carcinoma MDA-MB-435 cells to the basement membrane protein collagen type IV can be activated by treatment with arachidonic acid. We initially observed that this arachidonic acid-mediated adhesion was inhibited by the tyrosine kinase inhibitor genistein. Therefore, we examined the role of the mitogen-activated protein (MAP) kinase family tyrosine phosphorylation-regulated pathways in arachidonic acid-stimulated cell adhesion. Arachidonic acid stimulated the phosphorylation of p38, the activation of MAP kinase-activated protein kinase 2 (MAPKAPK2, a downstream substrate of p38), and the phosphorylation of heat shock protein 27 (a downstream substrate of MAP kinase-activated protein kinase 2). Treatment with the p38 inhibitor PD169316 completely and specifically inhibited arachidonic acid-mediated cell adhesion to collagen type IV. p38 activity was specifically associated with arachidonic acid-stimulated adhesion; this was demonstrated by the observation that 12-O-tetradecanoylphorbol 13-acetate-activated cell adhesion was not blocked by inhibiting p38 activity. Extracellular signal-regulated protein kinases (ERKs) 1 and 2 were also activated by arachidonic acid; however, cell adhesion to collagen type IV was not highly sensitive to PD98059, an inhibitor of MAP kinase kinase/ERK kinase 1 (MEK1) that blocks activation of the ERKs. c-Jun NH(2)-terminal kinase was not activated by arachidonic acid treatment of these cells. Together, these data suggest a novel role for p38 MAP kinase in regulating adhesion of breast cancer cells to collagen type IV.
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PMID:Arachidonic acid activates mitogen-activated protein (MAP) kinase-activated protein kinase 2 and mediates adhesion of a human breast carcinoma cell line to collagen type IV through a p38 MAP kinase-dependent pathway. 1075 39

A non-mycelial strain of wild-type Candida albicans strain 3153 A was produced by repeated subculturing on Sabouraud glucose agar, and maintained on yeast extract-peptone-glucose medium resulting in hydrophobic cells at 26 degrees C and hydrophilic cells at 37 degrees C. The behaviour of cells of this strain was studied in male BALB/c mice, immunocompromised by treatment with cyclophosphamide and cortisone acetate. An ex-vivo assay of cell adherence to tissue sections of liver, spleen, kidney and lymph-nodes was used. The adherence of yeast cells at 26 and 37 degrees C was predominantly produced by hydrophobic cells and was significantly greater in spleen and liver of immunosuppressed mice compared with the organs of control animals. Adhesion was observed in the white and red pulp as well as in the marginal zone of the spleen.
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PMID:Adherence in tissues of immunocompromised mice of a non-mycelium producing strain of Candida albicans. 1094 17

Adhesion of CD34+ hematopoietic progenitor cells (HPCs) to sinusoidal endothelium probably plays a key role in homing of transplanted CD34+ HPCs to the bone marrow (BM). We have investigated the role of various adhesion molecules in the interaction of purified CD34+ HPCs derived from BM or peripheral blood (PB) and a human BM-derived endothelial cell line. Adhesion of CD34+ HPCs to endothelial cells was measured with the use of a double-color flow microfluorimetric adhesion assay. In this assay, adhesion is measured under stirring conditions, simulating blood flow in sinusoidal marrow vessels. Adhesion of PB CD34+ cells to human BM endothelial cells (HBMECs) was observed only after interleukin (IL)-1beta prestimulation of the endothelial cells. This adhesion was strongly increased after addition of phorbol-myristate acetate (PMA). Adhesion of PB CD34+ cells to IL-1beta-prestimulated HBMECs was inhibited by blocking monoclonal antibodies (mAbs) against E-selectin and by neuraminidase treatment of the PB CD34+ cells. mAbs against very late activation antigen (VLA)-4 inhibited adhesion only when the E-selectin-mediated interaction was prevented. No clear inhibiting effect was found with blocking mAbs against beta2-integrins. Stimulation with the beta1-integrin-activating mAb, 8A2, induced adhesion of CD34+ cells to endothelial cells. In conclusion, stimulation of both endothelial cells and CD34+ HPCs is necessary for adhesion of CD34+ HPCs to endothelial cells. We furthermore demonstrated that E-selectin and VLA-4 mediated this adhesion.
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PMID:E-selectin and very late activation antigen-4 mediate adhesion of hematopoietic progenitor cells to bone marrow endothelium. 1104 18


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