Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of hypoglycaemic, hypoxic, and ischaemic conditions on high-affinity neurotransmitter transport was studied in the human astrocytoma clone D384 and the human neuroblastoma clone SH-SY5Y. Both cell lines expressed a sodium-dependent glutamate/aspartate transporter. Km values for D-[3H]aspartate uptake were 6.1 +/- 0.9 microM for D384 cells and 5.3 +/- 0.3 microM for SH-SY5Y cells (mean +/- SEM of three experiments). In addition, SH-SY5Y, but not D384, expressed a sodium-dependent noradrenaline transporter with Km = 0.6 +/- 0.1 microM (mean +/- SEM of three experiments). Up to 3 h of hypoglycaemic conditions had no effect on neurotransmitter uptake or on ATP levels of each cell line. In sharp contrast, during hypoxic conditions, the uptake of D-[3H]-aspartate and [3H]noradrenaline declined by 43-56% within 5 min. These reduced rates of neurotransmitter uptake were maintained over 30 min of hypoxic conditions. Five minutes of ischaemic conditions caused similar reductions in neurotransmitter uptake rates. A correlation between reductions in rates of neurotransmitter uptake and in ATP levels was observed for each cell line. Results are discussed in relation to other brain preparations, which are used as models of the nervous system to study the effects of ischaemic conditions on neurotransmitter and energy metabolism.
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PMID:Effects of ischaemic conditions on uptake of glutamate, aspartate, and noradrenaline by cell lines derived from the human nervous system. 791 90

The effect of the irreversible S-adenosyl-L-homocysteine hydrolase inhibitor, (Z)-5'-fluoro-4',5'-didehydro-5'-deoxyadenosine (MDL 28,842), on C-1300 murine neuroblastoma (MNB) cell proliferation in tissue culture and MNB tumor growth in vivo were investigated. MNB cells were incubated with MDL 28,842 at concentrations ranging from 8 x 10(-9) M to 1.6 x 10(-5) M for 3 days, and cell proliferation was determined by use of a CellTiter 96-well Proliferation Assay Kit. In tissue culture, MDL 28,842 inhibited MNB cell proliferation in a concentration-dependent manner, and the IC50 of MDL 28,842 against MNB in tissue culture was 1.8 x 10(-7) M. The response of in vivo tumor growth and host survival to MDL 28,842d was evaluated in a syngeneic mouse tumor model prepared by s.c. implantation of 1 x 10(6) MNB cells into A/J mice. Following palpation of a tumor mass, osmotic minipumps were implanted into each mouse. MDL 28,842 was infused at rates of 1.0 or 1.5 mg/kg/day over a 10-day period and 1.25 mg/kg/day over a 30-day period. The mean survival time of tumor-bearing mice significantly increased from 28.75 +/- 1.06 days (mean +/- 2 SEM) in the control group (diluent infusion) to 39.33 +/- 1.58 days, 44.11 +/- 1.74 days, and 41.0 +/- 1.30 days in the MDL 28,842-treated groups receiving 10-day infusions of 1.0 and 1.5 mg/kg/day or 30-day infusions of 1.25 mg/kg/day, respectively. No significant differences in survival rate were noted between groups receiving 10 vs 30 days of drug treatment.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Suppression of C-1300 murine neuroblastoma cell proliferation in tissue culture and tumor growth in vivo by (Z)5'-fluoro-4',5'-didehydro-5'-deoxyadenosine (MDL 28,842), an irreversible inhibitor of S-adenosyl-L-homocysteine hydrolase. 805 4

The murine neuroblastoma N1E-115 cell line possesses a high density of angiotensin II (AngII) receptors that can be solubilized with the zwitterionic detergent 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate. These solubilized binding sites exhibited high affinity for CGP-42112A and not Losartan, indicating that they were of the AT2 subtype. However, displacement of 125I-AngII with the AT2 nonpeptide antagonist PD-123319 resulted in a biphasic curve, suggesting heterogeneity of the AT2 receptor population in N1E-115 cells. In support of this view, separation of two receptor populations was accomplished with heparin-Sepharose chromatography. More specifically, three distinct protein peaks eluted from the heparin-Sepharose column, two of which bound 125I-AngII with high affinity and saturability. One of these binding peaks (peak I) eluted rapidly and represented approximately 80% of the total binding activity, whereas the remaining binding activity was contained within a second peak (peak III) that required the addition of 1.5 M NaCl for its complete elution. Pharmacological analysis revealed that both peaks of binding activity were exclusively AT2 receptors insofar as they exhibited high affinity for CGP-42112A and little or no affinity for the AT1-selective antagonist Losartan. However, whereas the nonpeptidic AT2-selective antagonist PD-123319 completely displaced the binding of 125I-AngII from peak I in a monophasic fashion (IC50 = 9.1 +/- 4.1 nM; mean +/- SEM; n = 3), PD-123319 was much less effective in displacing 125I-AngII from peak III (IC50 = 196 +/- 27 nM; mean +/- SEM; n = 3). Treatment of individual peaks with the reducing agent dithiothreitol caused a large increase in 125I-AngII specific binding in peak III, whereas a decrease in binding was observed in peak I. Moreover, GTP gamma S significantly reduced high-affinity agonist binding in peak I but not peak III, further suggesting heterogeneity in the AT2 receptor family. Finally, immunoblotting studies with polyclonal antisera raised against peak I specifically detected two proteins of 110 and 66 kDa, as is true in crude solubilized membranes, whereas no immunospecific proteins were detected in peak III. These same antisera immunoprecipitated 125I-AngII binding activity in peak I but were ineffective in peak III. Collectively, these results suggest that heparin-Sepharose chromatography can efficiently separate two pharmacologically, biochemically and immunologically distinct populations of AT2 receptors.
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PMID:Biochemical characterization of two distinct angiotensin AT2 receptor populations in murine neuroblastoma N1E-115 cells. 818 20

Using N1E-115 neuroblastoma cells as an experimental model, we have examined if four commonly used i.v. anaesthetic induction agents interact with 5-HT3 receptors. Specifically, we tested the hypothesis that the antiemetic effects of propofol may result from 5-HT3 receptor antagonism. Binding of tropisetron (a 5-HT3 selective reference compound), etomidate, ketamine, thiopentone and propofol to 5-HT3 receptors was assessed by measuring the displacement of [3H]BRL 43694 from whole N1E-115 cells. The rank order potency (Ki) was tropisetron (1.7 (SEM 0.2) nmol litre-1) >> etomidate (83.(4) mumol litre-1) > or = ketamine (97 (4) mumol litre-1) > thiopentone (177 (9) mumol litre-1) > propofol (819 (171) mumol litre-1). With the exception of thiopentone these effects were outside the clinical range and suggest that anaesthetic agents are unlikely to interact directly with 5-HT3 receptors, and that other mechanism(s) must underlie the antiemetic effects of propofol.
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PMID:Interaction of i.v. anaesthetic agents with 5-HT3 receptors. 877 9

Previous studies have demonstrated that components of the extracellular matrix can induce neurite extension and cell adhesion in the neuroblastoma x glioma hybrid cell line, NG108-15. Using standard intracellular recording techniques, we examined the resting membrane potential (RMP) and membrane excitability of NG108-15 cells differentiated under serum-free media with representative extracellular matrix (ECM) protein components as the substrate. Surfaces coated with collagen IV and a laminin-1 synthetic peptide induced a significantly (P < 0.05) more hyperpolarized RMP than control polystyrene surfaces. For example, after > or =8 days in culture NG108-15 cells plated on polystyrene exhibited a RMP of -33.2+/-0.8 mV (mean+/-SEM, n=158 cells) whereas cells cultured on the laminin-1 peptide C16 and collagen IV showed a RMP of -37.6+/-0.7 mV (n=157) and -37.5+/-1.5 mV (n=68), respectively. Furthermore, the proportions of cells on ECM substrates showing membrane excitability, i.e. evoked action potentials (APs) and the capability for regular firing, were significantly greater compared to those cells cultured on polystyrene. Among excitable cells cultured on the different substrates, characteristics of the action potentials, such as AP duration, amplitude, and the maximum rate of rise, dV/dtMAX, were examined in detail. While little or no differences were observed between polystyrene and the laminin-1 peptide groups, significant differences in the AP parameters were apparent for collagen IV. For example, dV/dtMAX for polystyrene and the laminin-1 peptide C16 were only 71.7+/-24.5 V/s (n=11) and 59.0+/-8.9 V/s (n=9), respectively, whereas cells cultured on collagen IV surfaces exhibited a dV/dtMAX reaching 156.1+/-22.0 V/s (n=7). These data support a role for ECM components in the maintenance of the RMP and membrane excitability in NG108-15 cells.
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PMID:Influence of extracellular matrix proteins on membrane potentials and excitability in NG108-15 cells. 962 95

Regional distribution of orexin-A-like immunoreactivity in the human brain and pituitary, and the presence of orexin-A-like immunoreactivity in the tumor tissues of pheochromocytomas, ganglioneuroblastomas and neuroblastomas were studied by radioimmunoassay. Expression of orexin mRNA was studied by reverse transcriptase polymerase chain reaction (PCR) method. Orexin-A-like immunoreactivity was detected in every region of human brain, but not in the pituitary. The highest concentration of orexin-A-like immunoreactivity in the human brain was found in hypothalamus (17.8 +/- 4.3 pmol/g wet weight, mean +/- SEM, n = 7), followed by thalamus, medulla oblongata, and pons. Orexin-A-like immunoreactivity was detected in the tumor tissues of ganglioneuroblastoma and neuroblastoma, but not in the tumor tissues of pheochromocytoma. Reverse phase high performance liquid chromatographic analyses of the orexin-A-like immunoreactivity in the human brain extracts and neuroblastoma extracts showed a single immunoreactive peak, which was eluted in an identical position to synthetic human orexin-A. Orexin mRNA was expressed in the hypothalamus and in the tumor tissues of ganglioneuroblastoma and neuroblastoma. These findings suggest that orexin-A is produced in the hypothalamus and transported to various brain regions via axons. In addition, this study has shown for the first time the production of orexin-A by ganglioneuroblastomas and neuroblastomas.
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PMID:Orexin-A in the human brain and tumor tissues of ganglioneuroblastoma and neuroblastoma. 1082 13

To identify molecular interaction partners of the cellular prion protein (PrP(C)), we sought to apply an in situ crosslinking method that maintains the microenvironment of PrP(C). Mild formaldehyde crosslinking of mouse neuroblastoma cells (N2a) that are susceptible to prion infection revealed the presence of PrP(C) in high molecular mass (HMM) protein complexes of 200 to 225 kDa. LC/MS/MS analysis identified three murine splice-variants of the neural cell adhesion molecule (N-CAM) in the complexes, which isolate with caveolae-like domains (CLDs). Enzymatic removal of N-linked sugar moieties did not disrupt the complexes, arguing that the interaction of PrP with N-CAM occurs through amino acid side-chains. Additionally, similar levels of PrP/N-CAM complexes were found in N2a and prion-infected N2a (ScN2a) cells. With the use of an N-CAM-specific peptide library, the PrP-binding site was determined to comprise beta-strands C and C' within the two consecutive fibronectin type III (FNIII) modules found in proximity of the membrane-attachment site of N-CAM. As revealed by in situ crosslinking of PrP deletion mutants, the PrP face of the binding site is formed by the N terminus, helix A (residues 144-154) and the adjacent loop region of PrP. N-CAM-deficient (N-CAM(-/-)) mice that were intracerebrally challenged with scrapie prions succumbed to disease with a mean incubation period of 122 (+/-4.1, SEM) days, arguing that N-CAM is not involved in PrP(Sc) replication. Our findings raise the possibility that N-CAM may join with PrP(C) in carrying out some as yet unidentified physiologic cellular function.
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PMID:Binding of neural cell adhesion molecules (N-CAMs) to the cellular prion protein. 1174 35

The inhibitory action of gangliosides GT1B, GD1A, GM3 and GM1 on cell proliferation and epidermal growth factor receptor (EGFR) phosphorylation was determined in the N-myc amplified human neuroblastoma cell line NBL-W. The IC50 of each ganglioside was estimated from concentration-response regressions generated by incubating NBL-W cells with incremental concentrations (5-1000 microm) of GT1B, GD1A, GM3 or GM1 for 4 days. Cell proliferation was quantitatively determined by a colourimetric assay using tetrazolium dye and spectrophotometric analysis, and EGFR phosphorylation by densitometry of Western blots. All gangliosides assayed, with the exception of GM1, inhibited NBL-W cell proliferation in a concentration-dependent manner. The IC50s for gangliosides GT1B [molecular weight (MW) 2129], GM3 (MW 1236), and GD1A (MW 1838) were (mean +/- SEM) 117 +/- 26, 255 +/- 29, and 425 +/- 44 m, respectively. In contrast, the IC50 for GM1 (MW 1547) could not be determined. Incubation of NBL-W cells with epidermal growth factor (EGF) concentrations ranging from 0.1 to 1000 ng/ml progressively increased cell proliferation rate, but it plateaued at concentrations above 10 ng/ml. EGFR tyrosine phosphorylation, however, was incrementally stimulated by EGF concentrations from 1 to 100 ng/ml. The suppression of EGF-induced EGFR phosphorylation differed for each ganglioside, and their respective inhibitory potencies were as follows: EGFR phosphorylation [area under curve (+ EGF)/area under curve (- EGF)]: control (no ganglioside added) = 8.2; GM1 = 8.3; GD1A = 6.7; GM3 = 4.87, and GT1B = 4.09. The lower the ratio, the greater the inhibitory activity of the ganglioside. Gangliosides GD1A and GT1B, which have terminal N-acetyl neuraminic acid moieties, as well as one and two N-acetyl neuraminic acid residues linked to the internal galactose, respectively, both inhibited cell proliferation and EGFR phosphorylation. However, GD1A was a more potent suppressor of cell proliferation and GT1B most effective against EGFR phosphorylation. GM3, which only has a terminal N-acetyl neuraminic acid, inhibited cell proliferation and EGFR phosphorylation almost equivalently. These data suggest that gangliosides differ in their potency as inhibitors of NBL-W neuroblastoma cell proliferation and EGFR tyrosine phosphorylation, and that perturbations in the differential expression of membrane glycosphingolipids may play a role in modulating neuroblastoma growth.
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PMID:Inhibition of human neuroblastoma cell proliferation and EGF receptor phosphorylation by gangliosides GM1, GM3, GD1A and GT1B. 1195 45

The objective of these studies was to characterize the effects of a broad range of prostanoid agonists upon the stimulation of cAMP production in National Cancer Bank (NCB-20; mouse neuroblastoma/hamster brain hybridoma) cells. The pharmacology of these functional responses in NCB-20 cells was compared with that of the classic endogenous IP receptor present on human platelets using [3H]-iloprost binding techniques. In both assay systems, agonists from the IP prostanoid class exhibited the highest affinities and functional potencies. Specific prostanoids exhibited the following rank order of potency (EC50 +/- SEM) in stimulating cAMP production in the NCB-20 cells: carbaprostacyclin (4.3 +/- 0.9 nM) = PGI2 (6.6 +/-1.5 nM) > iloprost (75+/-13 nM) > 11-deoxy PGE, (378+/-138 nM) > misoprostol (1,243+/-48) > PGE2 (3020+/-700 nM) > ZK-118182 (7265+/-455 nM). Iloprost wasthe most potent compound in the human platelet binding assay while prostanoidsfromthe DPand EP receptor classes showed modest affinity. These studies provide functional and binding information for a broad range of both natural and synthetic prostanoid receptor ligands at the endogenous IP receptor in two different cell types.
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PMID:Pharmacology of functional endogenous IP prostanoid receptors in NCB-20 cells: comparison with binding data from human platelets. 1199 17

The aim of this study was to explore the effect of 0NO-54918-07, a stable prostacyclin analogue, on the current-voltage (IV) curve and the intracellular Ca2+ concentration [Ca2+]i of NG108-15 neuroblastoma x glioma hybrid cells. The IV curve was measured with ramp pulses from -70 to 0 mV, and [Ca2+]i was determined with Fura 2. Bath application of 0.2 muM ONO-54918-07 reversibly increased the holding current at -70 mV by -81.1 +/- 14.8 pA (mean +/- SEM, n = 35) and the slope of the IV curve between -70 and -50 mV by the factor 2.24 +/- 0.24. The effect of 0.2 microM prostaglandin PGE1 was similar (DeltaI (hold) = -96.1 +/- 29.9 pA, g/g (control) = 2.72 +/- 0.44, n = 9). ONO-54918-07 concentrations of 0.04, 2 and 6 microM were also effective. From the dose-response curve, the concentration for the half maximal effect was obtained as 0.054 microM. When cells did not respond to ONO-54918-07, an effect could sometimes be elicited by a ramp pulse or by a second ONO-54918-07 application 30-50 min after the first. The effect of ONO-54918-07 was not affected by pre-treatment with the EP1 antagonists ONO-8713 or SC-51089. However, a 14-40 min pre-treatment with 1 microM RO3244794, a selective prostacyclin receptor (IP) antagonist, abolished the effect of 0.2 microM PGE1. The effect of 0.2 microM ONO-54918-07 vanished completely in the presence of 5 microM RO32446794. ONO-54918-07 and PGE1 produced a slow increase in [Ca2+]i that lasted at least 6 min. Delta[Ca2+]i induced by both substances reached approximately 12% of the peak Delta[Ca2+]i induced by application of bradykinin. In only a few cells, PGE1 produced a brief, transient rise of [Ca2+]i. Using reverse transcriptase polymerase chain reaction, a prominent expression of the IP was detected in NG108-15 cells. It is concluded that ONO-54918-07 mimics the effect of PGE1, supporting the notion that the PGE1 effect on NG108-15 cells is mediated by IP receptors.
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PMID:ONO-54918-07, a stable prostacyclin analogue, mimics the effect of prostaglandin PGE1 on NG108-15 cells. 1795 10


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