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 current status of the published work on the lipid composition of isolated brain cells is reviewed and some new work on the sphingolipids of these cells is presented. In spite of considerable differences in isolation techniques between different groups, the lipid analyses of different cell preparations are similar enough to permit several generalizations. This fact is an encouraging sign that cell separation methods have considerable usefulness in defining the composition of normal brain cells. It is a general finding that astrocytes have more lipid than neuronal perikarya but that the gross lipid composition of these two cell types is surprisingly similar. Oligodendroglial lipids are quite different from those of the other two cell types and are characterized by a high galactolipid content. Although such a lipid pattern might be expected in oligodendroglia, which are myelin-forming cells, axonal lipids have an even higher galactolipid content. In an effort to find more cell-specific patterns, the glycosphingolipids were examined in more detail. Differences were seen in the distribution and fatty-acid patterns of these minor lipids in neurons and astrocytes, although it may be premature to conclude that these differences will prove to be cell-specific. All of the isolated cells were found to contain galactosylceramide, sulfatide, glucosylceramide, dihexosylceramide, and gangliosides. The distribution of these lipids in the normal cells was found to differ considerably from that reported in cultured neuroblastoma cells or astrocytoma cells. Not only were gangliosides present in all cells but the ganglioside patterns of neurons and astrocytes were nearly identical. The fatty-acid patterns of the neuronal and astroglial sphingolipids generally do not resemble each other, and both are quite different from those found in oligodendroglia and axons. However, the fatty-acid composition of the sphingolipids from bovine oligodendroglia and from axons are similar and resemble those of myelin lipids. The fatty acids of glucosylceramide and dihexosylceramide are similar in all three cell types. They have rather large amounts of 16:0 and acids longer than C18; thus they are considerably different from the ganglioside fatty acids (which have mostly 15:0) isolated from the same fractions.
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PMID:The lipid composition of isolated brain cells and axons. 122 19

1. A new 17-kDa mammalian ribosomal protein (PR17) was purified to homogeneity from the rat exocrine pancreas. The purification procedure was based on acidic extraction of a heat-denatured homogenate, ammonium-sulfate precipitation, hydrophobic chromatography on phenyl-Sepharose and analytical reverse-phase HPLC on mu Bondapak C18. Fractions of interest were collected using an antiserum directed against the first (1-14) moiety of somatostatin (1-28). 30 micrograms pure RP17 were obtained from 1 g fresh pancreas. 2. A short 111-b cDNA encoding RP17 was amplified from rat pancreatic first-strand cDNA template by using two 64-fold degenerate heptadecamer primers in the DNA-polymerase-chain reaction. From the sequence of amplified cDNA, an unambiguous oligonucleotide probe was designed to screen a rat pancreatic cDNA library. A cDNA clone coding for RP17 was isolated, whose nucleotide sequence, with an open reading frame coding for 155 amino acids (molecular mass of 17,199 Da), confirmed the partial amino acid sequences directly obtained from the purified protein. 3. Northern-blot analysis showed that a similar 0.75-kb transcript was present in rat pancreas, in the rat pancreatic acinar cell line AR 4-2J and in the human neuroblastoma cell-line NB-OK-1, the highest level being in the latter two preparations, despite similar levels of RP17 in all three preparations, as tested with a rabbit antiserum directed against purified RP17. 4. The N-terminal sequence of both RP17 and the ribosomal protein YL43 from Saccharomyces cerevisiae (39 amino acid residues) showed a high degree of identity (77%), indicating that RP17 is a mammalian homolog of yeast ribosomal protein YL43.
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PMID:Purification, primary structure and molecular cloning of a rat ribosomal protein showing homology with yeast ribosomal protein YL34. 173 22

Sodium nitroprusside (SNP) stimulates cGMP formation to a greater extent in 20,000 g supernatant fractions of the human neuroblastoma clones NB1-G and SH-SY5Y than in the human astrocytoma clone D384. This suggests that these cell lines contain the soluble form of guanylate cyclase. Arachidonic, 8,11,14- and 11,14,17-eicosatrienoic acids inhibit SNP (10(-4) M)-stimulated cGMP formation more potently than the C18 unsaturated fatty acids linolenic and linoleic acids in D384 and NB1-G. In contrast the C20 saturated fatty acid, arachidic acid had little effect even at 10(-4) M concentration. In addition arachidonic and 8,11,14-eicosatrienoic acids inhibited basal guanylate cyclase activity, in NB1-G, over the same concentration range as they inhibited SNP-stimulated cGMP formation. No evidence could be obtained for the stimulation of guanylate cyclase by arachidonic acid in either NB1-G or D384. These results provide further support for suggestions that arachidonic acid or its metabolites may be important regulators of cGMP formation in the nervous system.
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PMID:The effect of unsaturated fatty acids on sodium nitroprusside stimulation of guanylate cyclase in the human astrocytoma clone, D384, and the human neuroblastoma clone, NB1-G. 196 40

Acylation of exogenously added galactosylsphingosine was demonstrated in intact NCB-20 neuroblastoma cells, a cell line that normally does not synthesize galactosylceramide. Labeling of cells with [3H]palmitic acid for 6 h in the presence of 100 microM exogenous galactosylsphingosine (GalSph) resulted in a more than 3-fold increase in the incorporation of label into the ceramide monohexoside fraction relative to controls. This increase, which was almost entirely due to the incorporation of labeled nonhydroxy fatty acid into galactosylceramide, was linear over a concentration range of 1-100 microM galactosylsphingosine and for the first 5 h after the addition of galactosylsphingosine. Similarly, the addition of 100 microM glucosylsphingosine resulted in a 3-fold increase of label incorporated into glucosylceramide. Incubation of cells with 100 microM GalSph and labeled fatty acids of various chain lengths revealed that the acylation of GalSph was specific for medium chain (C16-C18) nonhydroxy fatty acids, suggesting that this was an enzyme-mediated reaction. The enzymatic nature of GalSph acylation was further demonstrated when cells were incubated for 72 h with 15 microM [3H]galactosylsphingosine labeled in the galactose moiety. [3H]Galactosylceramide containing only medium chain non-hydroxy fatty acids accumulated linearly with time reaching a maximum at 48 h and was observed to be further metabolized to ceramide dihexoside. This acylation reaction may be potentially important for the removal of glycosylsphingosines in the cell.
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PMID:Acylation of exogenous glycosylsphingosines by intact neuroblastoma (NCB-20) cells. 226 23

Two human neuroblastoma cell lines, NCG and GOTO, were used to study the cytotoxic effect of gamma linolenic acid (GLA). The cell growth inhibition of these culture cells by GLA was found to be associated with striking membrane fatty acid modification. When culture cells were exposed to 20 micrograms/ml and 60 micrograms/ml GLA for 48 hr, polyenoic acids in cell membrane phospholipids (PC, PE, PI, PS) and triglyceride significantly increased; 1.8-21.0 fold for NCG and 1.04-11.5 fold for GOTO, in association with decreased monoenoic acids. The most remarkable changes were; increase of C18:3, C20:3, C20:4 and decrease of C18:1. CoQ10 (50 micrograms/ml) and vitamin E (10 microM) shown to protect against the cytotoxic effect of GLA did not modify the incorporation of GLA into tumor cells. These results indicate that the antitumor effect of GLA is probably due to cellular dysfunction caused by fatty acid modification after GLA incorporation.
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PMID:Fatty acid modification of cultured neuroblastoma cells by gamma linolenic acid relevant to its antitumor effect. 282 39

Human neuroblastoma cells (Platt) were detached from tissue culture substrata with a Ca2+ chelating agent, and then the suspended cells were extracted with a sodium dodecyl sulfate (SDS)-containing buffer to maximally solubilize their sulfate-radiolabeled proteoglycans. The majority of the high-molecular-weight material in these dissociative extracts was heparan sulfate proteoglycan, which resolves into two heterodisperse size classes upon gel filtration on columns of Sepharose CL4B. After removal of SDS from these extracts by hydrophobic chromatography on Sep-Pak C18 cartridges, extracts were further fractionated on various affinity matrices. All of the sulfate-radiolabeled material eluted as one peak from DEAE-Sephadex ion-exchange columns. In contrast, affinity fractionation on Sepharose columns derivatized with the heparan sulfate-binding protein, platelet factor-4, resolved three major and one minor subsets of these components. The nonbinding fraction contained some heparan sulfate proteoglycan and some chondroitin sulfate. The weak-binding fraction contained principally heparan sulfate proteoglycan, as well as a small amount of chondroitin sulfate proteoglycan; the gel-filtration properties of these proteoglycans before or after alkaline borohydride treatment indicated that they were small in size, containing perhaps 2 to 4 glycosaminoglycan chains. The high-affinity fraction eluted from platelet factor 4-Sepharose was composed entirely of "single-chain" heparan sulfate. A portion of the heparan sulfate proteoglycan of the original extract bound to the hydrophobic affinity matrix, octyl-Sepharose, and this hydrophobic proteoglycan partitioned into the nonbinding and weak-binding fractions of the platelet factor 4-Sepharose affinity columns. These studies reveal that the majority of the proteoglycan made by these neuronal cells in culture is of the heparan sulfate class, is small in size when compared to other characterized proteoglycans, and can be resolved into several overlapping subsets when fractionated on affinity matrices.
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PMID:Heparan sulfate proteoglycans of human neuroblastoma cells: affinity fractionation on columns of platelet factor-4+. 623 9

A homogeneous class of enkephalin receptors found in murine neuroblastoma clone N1E-115 (Chang, K.-J., and Cuatrecasas, P. (1979) J. Biol. Chem. 254, 2610-2618) has been confirmed using a centrifugation assay employing cellular membranes. In intact N1E-115 cells, synthetic methionine5-enkephalin inhibited prostaglandin E1-induced intracellular cyclic AMP formation in a naloxone-sensitive manner. Upon demonstrating intracellular methionine5-enkephalin immunocytochemically (Knodel, E., and Richelson, E. (1980) Brain Res. 197, 565-570), analyses of crude N1E-115 extract were made by radioimmunoassay or opiate receptor binding assay following fractionation by molecular sieve chromatography and high pressure liquid chromatography on a mu-Bondapak C18 column. Extracted methionine5-enkephalin immunoreactive material behaved similarly to synthetic methionie5-enkephalin in these analyses. Growth curve studies of the N1E-115 cells indicated that the quantity of methionine5-enkephalin immunoreactive material synthesized per milligram of cellular protein and the maximum number of enkephalin receptor sites per milligram of membrane protein increased as the cells progressed from logarithmic to stationary phase, with no change in the apparent affinity of the enkephalin receptors for [3H]methionine5-enkephalin. These data suggest that adrenergic clone N1E-115 has functional methionine5-enkephalin membrane receptors, that this clone synthesizes methionine5-enkephalin, and that both the enkephalin receptor number and the content of stored methionine5-enkephalin are regulated with respect to cell division.
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PMID:Function and regulation of methionine5-enkephalin and its receptors in murine neuroblastoma cells. 627 78

The efficiency of ion-pair reversed-phase HPLC on a Vydac C18 column with 50 mM ammonium acetate (pH 4.75)-methanol-acetonitrile (88:9:3, v/v/v) as the mobile phase with isocratic separation and fluorescence detection for the determination of cAMP in cellular extracts was evaluated. This method was compared with a radioimmunoassay technique in terms of linearity, reproducibility and sensitivity. No interactions with other nucleotides such as AMP, ADP, ATP and cGMP were observed. Application to the measurement of cAMP modifications was studied in a neuroblastoma cell line: LA-N-2 cells stimulated by a neuropeptide, vasoactive intestinal peptide.
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PMID:High-performance liquid chromatographic determination of cyclic 3',5'-AMP with fluorescence detection. Vasoactive intestinal peptide-induced modification of its concentration in neuroblastoma cells. 795 67

The BE (2)-M17 human neuroblastoma has previously been shown to express corticotropin-releasing factor (CRF) mRNA following retinoic acid treatment. It is demonstrated in this report that both cell extracts and cell incubation medium of retinoic acid-treated BE (2)-M17 cells were shown to contain CRF-like immunoreactivity (CRF-LI) by RIA. CRF-LI secretion and content were also dose-dependently increased by forskolin. In addition, cell extracts were applied to a C18 Vydac column and peak CRF-LI from the collected fractions was shown to coincide in time of elution with peak immunoreactivity seen with oxidized synthetic CRF standard. Thus, in containing the CRF peptide, the BE (2)-M17 cells are useful models for further study of CRF cellular and genetic regulation.
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PMID:The BE (2)-M17 neuroblastoma cell line synthesizes and secretes corticotropin-releasing factor. 798 90

Molecular determinants of biological activity of gangliosides are generally believed to be carbohydrate in nature. However, our studies of immunomodulation by highly purified naturally occurring tumor gangliosides provide another perspective: while the immunosuppressive activity of gangliosides requires the intact molecule (both carbohydrate and ceramide moieties), ceramide structure strikingly influences ganglioside immunosuppressive activity. Molecular species of human neuroblastoma GD2 ganglioside in which the ceramide contains a shorter fatty acyl chain (C16:0, C18:0) were 6- to 10-fold more active than those with a longer fatty acyl chain (C22:0/C24:1, C24:0). These findings were confirmed in studies of ceramide species of human leukemia sialosylparagloboside and murine lymphoma GalNAcGM1b. Gangliosides that contain shorter-chain fatty acids (and are most immunosuppressive) are known to be preferentially shed by tumor cells. Therefore, the results suggest that the tumor cell is optimized to protect itself from host immune destruction by selective shedding of highly active ceramide species of gangliosides.
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PMID:Ceramide structure predicts tumor ganglioside immunosuppressive activity. 812 17


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