iloprost and Neuroblastoma

iloprost has been researched along with Neuroblastoma* in 13 studies

Reviews

1 review(s) available for iloprost and Neuroblastoma

ArticleYear
Agonist regulation of cellular levels of the stimulatory guanine nucleotide-binding protein, Gs, in wild type and transfected neuroblastoma-glioma hybrid NG108-15 cells.
    Biochemical Society transactions, 1993, Volume: 21, Issue:2

    Topics: Adenosine; Adenosine-5'-(N-ethylcarboxamide); Animals; Down-Regulation; Glioma; GTP-Binding Proteins; Hybrid Cells; Iloprost; Isoproterenol; Neuroblastoma; Transfection; Tumor Cells, Cultured

1993

Other Studies

12 other study(ies) available for iloprost and Neuroblastoma

ArticleYear
The effect of non-prostanoid prostacyclin mimetics on cyclic AMP production by neuronal SK-N-SH cells.
    Advances in experimental medicine and biology, 1997, Volume: 433

    Topics: Acetates; Cell Line; Cyclic AMP; Epoprostenol; Humans; Iloprost; Imidazoles; Kinetics; Neuroblastoma; Neurons; Oxazoles; Phenoxyacetates

1997
Inhibition of ADP-ribosyltransferase increases synthesis of Gs alpha in neuroblastoma x glioma hybrid cells and reverses iloprost-dependent heterologous loss of fluoride-sensitive adenylate cyclase.
    Biochemical pharmacology, 1995, Mar-15, Volume: 49, Issue:6

    Exposure of NG108-15 cells to 50 mM nicotinamide [an inhibitor of mono(ADP-ribosyl)transferase] for 18 hr led to an increase in membrane associated Gs alpha measured either as cholera toxin substrate or by immunoblotting with a specific antiserum. Prolonged exposure of NG108-15 cells to iloprost is followed by homologous loss of iloprost sensitivity, and heterologous loss of fluoride-dependent activation of adenylate cyclase. Nicotinamide reversed the loss of fluoride sensitivity, but failed to restore iloprost-dependent activation of adenylate cyclase. These results with nicotinamide in NG108-15 cells contrasted with those from platelets, which also exhibit heterologous desensitization of fluoride sensitivity following prolonged exposure to iloprost. Treatment of platelets with 50 mM nicotinamide for 18 hr led to an increase of 75.0 +/- 19.4% in the amount of membrane associated cholera toxin substrate. However, there was no associated increase in the abundance of Gs alpha as determined by immunoblotting. Furthermore, in platelets there was no restoration by nicotinamide of the iloprost-dependent loss of fluoride-sensitive adenylate cyclase activity. It follows that heterologous desensitization in platelets is accompanied by inactivation of Gs alpha, which is retained within the plasma membrane in its inactive state. The nicotinamide-dependent increase in the abundance of membrane associated cholera toxin substrate and immunoreactive Gs alpha in NG108-15 cells is associated with an increase of 72.0 +/- 20.3% in the levels of mRNA encoding Gs alpha. The capacity of nicotinamide to increase the abundance of membrane associated Gs alpha was reversed when the cells were cultured in the presence of 20 micrograms/mL cycloheximide. These results suggest that the ability of nicotinamide to increase the abundance of Gs alpha in NG108-15 cells is mediated by de novo protein synthesis.

    Topics: Adenylyl Cyclase Inhibitors; ADP Ribose Transferases; Blood Platelets; Fluorides; Glioma; GTP-Binding Proteins; Hybrid Cells; Iloprost; Neuroblastoma; Niacinamide; Poly(ADP-ribose) Polymerase Inhibitors; Tumor Cells, Cultured

1995
The effect of colchicine on cyclic AMP accumulation in NG108-15 cells.
    Biochemical Society transactions, 1995, Volume: 23, Issue:1

    Topics: Animals; Cell Line; Colchicine; Colforsin; Cyclic AMP; Glioma; GTP-Binding Proteins; Hybrid Cells; Iloprost; Kinetics; Mice; Neuroblastoma; Rats; Receptors, Prostaglandin; Tumor Cells, Cultured

1995
Interaction of the beta 2-adrenoceptor with epitope-tagged Gs alpha in NG108-15 cells.
    Biochemical Society transactions, 1995, Volume: 23, Issue:1

    Topics: Adenylyl Cyclases; Animals; Down-Regulation; Epitopes; Glioma; GTP-Binding Proteins; Hemagglutinin Glycoproteins, Influenza Virus; Hemagglutinins, Viral; Humans; Hybrid Cells; Iloprost; Kinetics; Mice; Neuroblastoma; Rats; Receptors, Adrenergic, beta; Receptors, Prostaglandin; Recombinant Proteins; Transfection; Tumor Cells, Cultured; Viral Envelope Proteins

1995
Agonist regulation of high affinity [3H] forskolin binding as a measure of GS alpha-adenylyl cyclase interactions.
    Biochemical Society transactions, 1995, Volume: 23, Issue:1

    Topics: Adenylyl Cyclases; Animals; Binding Sites; Binding, Competitive; Cell Membrane; Colforsin; Glioma; GTP-Binding Proteins; Homeostasis; Hybrid Cells; Iloprost; Kinetics; Mice; Neuroblastoma; Rats; Signal Transduction; Tumor Cells, Cultured

1995
Effects of acute and chronic ethanol on cyclic AMP accumulation in NG108-15 cells: differential dependence of changes on extracellular adenosine.
    British journal of pharmacology, 1995, Volume: 114, Issue:7

    1. This study investigated the effects of acute and chronic ethanol on basal, agonist- and forskolin-stimulated cyclic AMP formation in NG108-15 mouse neuroblastoma x rat glioma hybrid cells, and examined the role of changes in extracellular adenosine concentrations on the effects observed. 2. NG108-15 cells incubated acutely with ethanol (1-200 mM) displayed concentration-dependent increases in basal and iloprost-stimulated (300 nM; a prostanoid IP receptor agonist) cyclic AMP accumulation but a concentration-dependent decrease in forskolin-stimulated (10 microM) accumulation. 3. Cells treated chronically with ethanol (200 mM) for 48 h displayed increases over control in basal, iloprost- (0.001-10 microM) and forskolin (0.01-100 microM)-stimulated cyclic AMP formation. However, chronic ethanol did not affect [3H]-iloprost binding to cell membranes. 4. Inclusion of adenosine deaminase (ADA; 1 unit ml-1) during the incubation period to measure cyclic AMP accumulation completely abolished the increase in basal accumulation following chronic ethanol, but did not affect the increase in iloprost stimulation. On the other hand ADA partially reversed the increase in forskolin stimulation following chronic ethanol, but even in the presence of high concentrations of ADA (5 units ml-1) the forskolin stimulation remained elevated above control. 5. Cells treated chronically with the adenosine receptor agonist 5'-(N-ethylcarboxamido)-adenosine (NECA; 10 microM for 48 h) displayed a reduction in subsequent NECA- and forskolin-stimulated cyclic AMP accumulation, but iloprost stimulation was not affected. ADA included acutely during the incubation period to measure cyclic AMP accumulation abolished the reduction in forskolin but not NECA stimulation produced by the chronic NECA pretreatment. 6. We have previously noted that ethanol inhibits NG108-15 cell proliferation and alters cell morphology.To mimic this, cells were incubated in the absence of foetal calf serum for 48 h. Following this time, basal, iloprost- and forskolin-stimulated cyclic AMP formation was enhanced over that in cells grown in the presence of serum.7. These results indicate that chronic ethanol enhances cyclic AMP formation in intact NG108-15 cells by more than one mechanism: one involves increased extracellular adenosine concentrations and the other a change in the transduction system beyond the receptor, possibly involving the adenylyl cyclase enzyme. Furthermore the ethanol-induced changes in cycl

    Topics: Adenosine; Adenosine Deaminase; Animals; Colforsin; Cyclic AMP; Dose-Response Relationship, Drug; Ethanol; Iloprost; Mice; Neuroblastoma; Rats; Tumor Cells, Cultured

1995
Characterization of platelet activity in neuroblastoma.
    Journal of pediatric surgery, 1994, Volume: 29, Issue:5

    A study was conducted to characterize the platelet aggregation induced by neuroblastoma tissue to investigate the mechanism of hypercoagulability in patients with neuroblastoma. The patients whose tumor tissues were examined had been shown clinically to have enhanced platelet activity. Platelet aggregation induced by neuroblastoma tissue extract was compared with that of other pediatric tumors. The effects of pretreatment with an antithrombin agent and prostacyclin (PGI2) on the platelet aggregation induced by tumor tissue extracts were also evaluated. Tissue extracts of 12 of 15 neuroblastomas, 3 of 3 Wilms' tumors, and 1 pheochromocytoma were demonstrated to have an activity that potentiated platelet aggregation in vitro. The platelet aggregation induced by tissue extracts of neuroblastomas and other tumor tissues was suppressed almost completely by pretreatment with a PGI2 analogue. The aggregation induced by neuroblastomas and the pheochromocytoma was also suppressed by pretreatment with an antithrombin agent, argatroban, whereas the aggregation induced by Wilms' tumors was not suppressed by this agent. These results suggest that (1) malignant tumors in children also have some chemical substances that sensitize platelet activity, such as those in adult cancers, and (2) thrombin is one of the mediators stimulating platelet aggregation in cases of neuroblastoma, although it is unlikely to be a contributing factor in other pediatric malignancies such as Wilms' tumor.

    Topics: Antithrombins; Arginine; Child, Preschool; Female; Humans; Iloprost; Infant; Infant, Newborn; Kidney Neoplasms; Male; Neuroblastoma; Pheochromocytoma; Pipecolic Acids; Platelet Aggregation; Sulfonamides; Tissue Extracts; Wilms Tumor

1994
Gs alpha-dependent and -independent desensitisation of prostanoid IP receptor-activated adenylyl cyclase in NG108-15 cells.
    European journal of pharmacology, 1994, Jul-15, Volume: 268, Issue:2

    NG108-15 mouse neuroblastoma x rat glioma cells were treated with the prostanoid IP receptor agonist iloprost (1 microM) and the time course of changes in the levels of prostanoid IP receptors, adenylyl cyclase activity, and the alpha-subunit of the stimulatory guanine nucleotide binding regulatory protein, Gs, were measured. Incubation of cells with iloprost produced a biphasic time course of desensitisation of prostanoid IP receptor-activated adenylyl cyclase. Parallel analysis of iloprost-induced loss of membrane Gs alpha, NaF-stimulated adenylyl cyclase and [3H]iloprost binding suggested only monophasic curves, with t0.5 values similar to the initial phase of desensitisation of iloprost-stimulated adenylyl cyclase activity. This suggests that the loss of receptor and Gs alpha occur at the same time and account for the initial period of desensitisation due to iloprost pretreatment. Pretreatment of NG108-15 cells with cholera toxin produced a near complete loss of membrane-associated Gs alpha, but the loss of [3H]iloprost binding due to iloprost treatment was not affected by pretreatment with cholera toxin, suggesting that prostanoid IP receptors can be down-regulated in the absence of any coupling to Gs. The second phase of desensitisation of iloprost-stimulated adenylyl cyclase activity, during which there was no further change in NaF-stimulated adenylyl cyclase or in the membrane levels of Gs alpha, was not due to protein kinase A activation, since elevating intracellular cyclic AMP levels with forskolin did not subsequently decrease iloprost-stimulated adenylyl cyclase activity or [3H]iloprost binding. These results demonstrate that iloprost pretreatment of NG108-15 cells induces two distinct phases of desensitisation; an initial desensitisation due to concurrent loss of prostanoid IP receptors and Gs alpha, and then a further desensitisation by an as yet uncharacterized mechanism during which there is no further loss of Gs alpha.

    Topics: Adenylyl Cyclases; Animals; Cholera Toxin; Cyclic AMP-Dependent Protein Kinases; Enzyme Activation; Glioma; GTP-Binding Proteins; Guanylyl Imidodiphosphate; Hybrid Cells; Iloprost; Mice; Neuroblastoma; Rats; Receptors, Prostaglandin; Tumor Cells, Cultured

1994
Gs alpha is a substrate for mono(ADP-ribosyl)transferase of NG108-15 cells. ADP-ribosylation regulates Gs alpha activity and abundance.
    The Biochemical journal, 1992, Nov-15, Volume: 288 ( Pt 1)

    NG108-15 neuroblastoma x glioma somatic hybrid cells were permeabilized in the presence of [32P]NAD+ and then cultured for 18 h. Resolution of the cell proteins on polyacrylamide gels revealed [32P]ADP-ribosylation of five major protein species with molecular mass values of 52 kDa, 44 kDa, 35 kDa, 30 kDa and 25 kDa. A similar pattern of labelling was also seen when NG108-15 cell membranes were incubated with [32P]NAD+ and hydrolysis of the product revealed mono(ADP-ribosyl)ation. Immunoprecipitation of these products with anti-Gs alpha antiserum revealed a single band identical to cholera toxin substrate. Culture of [32P]NAD(+)-loaded cells for 18 h in the presence of 50 mM-nicotinamide inhibited the eukaryotic mono(ADP-ribosyl)transferase activity. Inhibition of the eukaryotic enzyme was also accompanied by an increase in the abundance of Gs alpha, whether measured by Western blotting with anti-Gs alpha antibody (two separate antisera) or by cholera toxin-dependent [32P]ADP-ribosylation. There was no accompanying change in the abundance of G beta. The increase in Gs alpha abundance in nicotinamide-treated NG108-15 cells was accompanied by a 2-fold increase in basal adenylate cyclase activity (measured in the presence of GTP), and by a smaller but significant increase in iloprost-dependent activation of adenylate cyclase. Receptor number or affinity was not affected by nicotinamide, since this treatment did not alter the binding parameters of [3H]iloprost to NG108-15 cell membranes. Short-term exposure of cells to nicotinamide for 1 h revealed no significant difference in either basal or agonist-stimulated adenylate cyclase activity. These results reveal that mono(ADP-ribosyl)ation of Gs alpha by eukaryotic ADP-ribosyltransferase modifies the abundance and activity of Gs alpha in NG108-15 cells, and hence may play a role in the hormonal regulation of cell function.

    Topics: Adenosine Diphosphate Ribose; ADP Ribose Transferases; Blotting, Western; Cholera Toxin; Glioma; GTP-Binding Proteins; Hybrid Cells; Iloprost; Immunosorbent Techniques; NAD; Neuroblastoma; Niacinamide; Substrate Specificity; Tumor Cells, Cultured

1992
Segregation of discrete GS alpha-mediated responses that accompany homologous or heterologous desensitization in two related somatic hybrids.
    British journal of pharmacology, 1990, Volume: 99, Issue:2

    1. Prostacyclin and adenosine A2 receptors activate adenylate cyclase in the neuroblastoma hybrid cell lines NG108-15 and NCB-20. Prolonged exposure of NG108-15 cells to iloprost (a stable analogue of prostacyclin) results in a subsequent reduction in the capacity for adenylate cyclase activation by iloprost, the adenosine analogue 5'-(N-ethyl)-carboxamidoadenosine (NECA) or NaF. In contrast prolonged exposure of NCB-20 cells to iloprost results only in the loss of iloprost responsiveness. 2. Iloprost pretreatment of NG108-15 cells also magnified the morphine-dependent inhibition of iloprost-stimulated adenylate cyclase activity from 36 to 48%. This change was not due to lower iloprost stimulation following desensitization, since the % inhibition of adenylate cyclase activity by morphine in control cells was constant irrespective of enzyme activity. 3. These heterologous effects observed in NG108-15 cells following iloprost pretreatment may involve changes in the GS alpha protein, since there was a reduction of about 30% in the cholera toxin-induced [32P]-ADP-ribosylation of a 45 kDa protein from cell membranes (corresponding to the extent of loss of NECA or NaF responsiveness). A similar reduction was not observed in NCB-20 cells. 4. These results indicate that iloprost pretreatment induces different forms of desensitization in NG108-15 and NCB-20 cell lines. The heterologous desensitization in the former may, like the human platelet, involve a functional loss of GS alpha from the cell membrane. Changes in the activity of GS alpha may also account for the heterologous effects on receptors that mediate inhibition of adenylate cyclase.

    Topics: Adenosine; Adenosine Diphosphate; Adenosine-5'-(N-ethylcarboxamide); Adenylyl Cyclase Inhibitors; Adenylyl Cyclases; Animals; Cell Line; Epoprostenol; GTP-Binding Proteins; Hybrid Cells; Iloprost; Kinetics; Mice; Morphine; Neuroblastoma; Phosphorus Radioisotopes; Receptors, Epoprostenol; Receptors, Prostaglandin; Sodium Fluoride

1990
NaF and guanine nucleotides modulate adenylate cyclase activity in NG108-15 cells by interacting with both Gs and Gi.
    British journal of pharmacology, 1990, Volume: 100, Issue:2

    1. NaF (10 mM) produced a 2-3 fold increase in adenylate cyclase activity in homogenates of NG108-15 cells incubated in the presence of 1 microM GTP. Higher concentrations of NaF suppressed adenylate cyclase activity. 2. In the presence of the adenosine receptor agonist 5'-(N-ethyl)-carboxamidoadenosine (NECA; 100 microM) or the prostacyclin receptor agonist iloprost (10 nM), NaF produced a much smaller increase in adenylate cyclase activity, whereas in the presence of a saturating concentration of iloprost (1 microM), NaF only inhibited adenylate cyclase activity. 3. Similarly, Gpp(NH)p activated basal adenylate cyclase activity, and inhibited 1 microM iloprost-activated enzyme activity. In the presence of 10 microM forskolin, NaF or Gpp(NH)p increased adenylate cyclase activity synergistically. Analysis of concentration-effect curves indicated that NaF (2 mM) or Gpp(NH)p (100 microM) increased the potency with which forskolin activated adenylate cyclase, whilst reducing the maximum activation of adenylate cyclase by iloprost. 4. Opiate receptors mediate inhibition of adenylate cyclase, and the opiate agonist morphine (100 microM) reduced the capacity of NaF or Gpp(NH)p to inhibit iloprost-activated adenylate cyclase. Unexpectedly, pertussis toxin treatment enhanced the ability of NaF or Gpp(NH)p to inhibit iloprost-activated adenylate cyclase. 5. In the absence of GTP, NaF and Gpp(NH)p remained able both to activate basal adenylate cyclase and to be synergistic with forskolin in activating the enzyme. In contrast the ability of NaF and Gpp(NH)p to inhibit iloprost-activated adenylate cyclase was substantially lost in the absence of added GTP. These results suggest that NaF modulates adenylate cyclase activity in NG108-15 cell membranes by interacting with the alpha subunits of both G0 and Gi regulatory proteins. The effects of NaF and Gpp(NH)p are critically dependent on the prior mode and extent of activation or inhibition of this transmembrane signalling pathway. This simple system may be of use in assessing alterations in GSO-O interaction following manipulations such as hormone receptor desensitization.

    Topics: Adenosine; Adenosine-5'-(N-ethylcarboxamide); Adenylate Cyclase Toxin; Adenylyl Cyclase Inhibitors; Animals; Cell Membrane; Colforsin; Enzyme Activation; Epoprostenol; GTP-Binding Proteins; Guanine Nucleotides; Guanosine Triphosphate; Guanylyl Imidodiphosphate; Iloprost; Mice; Morphine; Nervous System Neoplasms; Neuroblastoma; Pertussis Toxin; Sodium Fluoride; Tumor Cells, Cultured; Virulence Factors, Bordetella

1990
The use of a prostacyclin analogue, [3H]iloprost, for studying prostacyclin-binding sites on human platelets and neuronal hybrid cells.
    Bioscience reports, 1984, Volume: 4, Issue:11

    The stable prostacyclin analogue [3H]iloprost has been used for labelling prostacyclin-binding sites on human platelets and NCB-20 neuronal hybrid cells. The ligand-binding properties of the sites have been determined and correlate well with stimulation of cAMP synthesis in NCB-20 cells and inhibition of aggregation in human platelets.

    Topics: 1-Methyl-3-isobutylxanthine; Animals; Binding, Competitive; Blood Platelets; Brain; Cell Line; Cell Membrane; Cricetinae; Cricetulus; Cyclic AMP; Epoprostenol; Humans; Hybrid Cells; Iloprost; Kinetics; Mice; Neuroblastoma; Neurons; Receptors, Cell Surface; Receptors, Epoprostenol; Receptors, Prostaglandin

1984