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)

Medulloblastoma, a common pediatric brain tumor, is a primitive neuroectodermal tumor which often displays neuronal and/or glial characteristics. We have investigated the consequences of treating cell lines derived from a human medulloblastoma with glia maturation factor-beta (GMF-beta), a protein found in mammalian brain. GMF-beta promotes growth arrest and morphological alteration of cultured glioma and neuroblastoma cells. The proliferation of medulloblastoma cells was arrested 24-48 hr after exposure to human recombinant GMF-beta. During the same period, treated cells acquired a morphology similar to that of mature astrocytes. By 72 hr, all treated cells bound an antibody against glial fibrillary acidic protein (GFAP), a distinguishing biochemical feature of mature astrocytes. Immunoreactivity was accompanied by de novo expression of GFAP mRNA. Our observations are the first demonstration of the induction of morphological and biochemical characteristics of mature astrocytes in cultured medulloblastoma-derived cells by an exogenous factor.
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PMID:Expression of glial fibrillary acidic protein in human medulloblastoma cells treated with recombinant glia maturation factor-beta. 129 57

Mouse neuroblastoma x rat glioma hybrid NG108-15 cells form cholinergic synapses with rat or mouse muscle cells in culture. The rate of synapse formation is greatly dependent on intracellular cyclic AMP concentrations. The synapse formation is lower in the presence of glia maturation factor, a partially purified brain extract. Once the synapse between NG108-15 cells and myotubes has been formed, this synapse is stable for days. Extracellular application of serotonin, PGF2 alpha, PGD2, neurotensin and bradykinin on NG108-15 cells increases synaptic transmission. Since bradykinin increases the level of intracellular inositol 1,4,5-trisphosphate (InsP3), bradykinin-induced facilitation is due to InsP3-dependent elevation of intracellular Ca concentrations.
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PMID:Cholinergic synapse formation between NG108-15 and muscle cells and modulation of transmission. 217 13

Glia maturation factor beta (GMF-beta) is a 17-kDa growth regulating protein isolated from the brain. The effect of bovine GMF-beta on neurons was tested on the neuroblastoma line N18 and the pheochromocytoma line PC12. GMF-beta inhibited the proliferation of N18 cells and promoted their neurite outgrowth, with an increase in neurofilament protein, but had no effect on PC12 cells. This was in contrast to nerve growth factor (NGF) which regulated PC12 but not N18. Acidic fibroblast growth factor (FGF), on the other hand, had a weak effect on PC12 but none on N18. Antisera against GMF-beta and NGF neutralized the biological activity of the corresponding growth factors but showed no cross-neutralization. Fluorescence visualization revealed the binding of GMF-beta to N18 cells but not to PC12 cells; the opposite was true with NGF.
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PMID:Glia maturation factor beta regulates the growth of N18 neuroblastoma cells. 230 71

A protein has been isolated from bovine brains by using a modification of the procedure used to purify glia maturation factor. The method consists of ammonium sulfate precipitation, chromatography with DEAE-Sephacel, Sephadex G-75, and hydroxylapatite columns, passage through a heparin-Sepharose column, and finally fractionation by reverse-phase HPLC with a C4 column. The isolated protein reacts strongly with the mouse monoclonal antibody G2-09 and has a molecular weight of approximately 17,000 and an isoelectric point of pH 4.9. The N terminus is blocked, but tryptic digestion releases 28 peptides, 8 of which have been sequenced. The total known residues add up to more than two-thirds of the entire 140-residue protein, estimated from amino acid composition, and show no sequence homology with any known protein. Reversible thermal renaturation greatly enhances its biological activity. The purified protein stimulates differentiation of normal neurons as well as glial cells. It inhibits the proliferation of the N-18 neuroblastoma line and the C6 glioma line while promoting their phenotypic expression. We designate this protein glia maturation factor beta.
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PMID:Purification and characterization of glia maturation factor beta: a growth regulator for neurons and glia. 272 56

Glial growth inhibitory factor (GGIF), derived from the culture medium of mouse neuroblastoma cell (NAs-1), lowered the DNA synthesis and cell multiplication of normal rat glioblasts induced by glia maturation factor (GMF). The inhibitory action of GGIF depended on the concentration of GMF in the culture medium, and was of an uncompetitive type on kinetic analysis. GGIF showed the inhibitory activity at a late stage of the G1 phase or early stage of the S phase. The factor, however, failed to inhibit the differentiation-promoting activity of GMF. The data strongly suggest that the dual activities of GMF, the promotion of glial proliferation and differentiation, may be elicited by mutually independent intracellular processes.
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PMID:Functional dissociation of dual activities of glia maturation factor: inhibition of glial proliferation and preservation of differentiation by glial growth inhibitory factor. 359 69

The presence of glia maturation factor (GMF)-like activity was demonstrated in rat astrocytoma cells (C6 cells). The extracts of C6 cells enhanced the DNA synthesis of cultured glioblasts 3-fold at the maximum, inducing such morphological changes as extrusion of processes. C6 cells also showed a proliferative response to the extracts, though the responsiveness in terms of effective concentration of C6 extracts was about a half of the glioblast responsiveness. The extracts lowered growth rate of neuroblastoma cells and especially decreased their DNA synthesis without a morphological differentiation.
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PMID:Glial cell growth-promoting factor in astrocytoma (C6) cell extracts. 730 29

The effects of diphenylhydantoin (DPH) and other anticonvulsants on the growth of glial cells as well as neuroblastoma cell lines was studied. The DPH inhibition of the DNA synthesis was most marked in rat fetal glioblasts induced by glia maturation factor (GMF) among the cell lines studied, and that in C6 cells. The IC(50) of DPH for glioblasts and C6 cells were about 0.2 and 0.4 mM, respectively. The inhibitory effects of DPH and valproate on DNA synthesis was specific for glial cells, and the DNA synthesis of such neuronal cell lines as Neuro2a, NAs-1, and PC12 was unaffected at pharmacological concentrations. Diazepam inhibited the DNA synthesis of all cell types examined in the contrary to DPH, which preferentially inhibited glial cells. Phenobarbital showed no effect, and thiopental inhibition was <30% of the DNA synthesis in control condition with all cell lines used at the concentration of 0.4 mM. Both DPH and diazepam suppressed the extrusion induced by GMF of the glioblast processes, and the neuroblastoma cell neurites that had extended in the presence of dibutylyl cAMP disappeared by the exposure to DPH, suggesting that these drugs affected the cytoskeletal rearrangement of both glial and neuronal cells during morphological differentiation.
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PMID:Inhibition by diphenylhydantoin of growth and morphological differentiation of glial cells: Implication of calcium. 2050 37

When quiescent rat glioblasts were stimulated by glia maturation factor (GMF), their intrinsic Ca(2+)-dependent phosphorylation of proteins, especially that of M(r) 100 k protein, increased. The phosphorylation of M(r) 100 k protein in the homogenate started rising 13 h (S phase) after GMF stimulation and reached the maximal level (8-fold greater than the control) at 26 h. Phosphorylation was also detected in intact cells by the use of [(32)P]orthophosphate. Calmodulin augmented and W-7 (calmodulin inhibitor) slightly inhibited the phosphorylation, suggesting that Ca(2+)/calmodulin-dependent protein kinase may partly be involved in phosphorylation of the M(r) 100 k protein. Subcellular fractionation experiments revealed that both M(r) 100 k protein and its kinase were localized exclusively in the cytosol. We also found marked phosphorylation of M(r) 100 k protein in neural tumor cell lines, mouse neuroblastoma (Neuro2a and NAs-1) and glioma (C6 and 354A). Since the peptide maps of (32)P-labeled peptides obtained by chemical cleavage from M(r) 100 k protein of the cells were identical to those of glioblasts, the M(r) 100 k proteins, regardless of cell origin, may be closely related in structure. Growth inhibitors, W-7 (50 ?M), puromucin (2 ?M), spongoadenosine (50 ?M), diphenylhydantoin (0.3 mM), ?-sialosyl cholesterol (20 ?g/ml) and protein kinase inhibitor, K252a (50 nM), lowered the phosphorylation of the M(r) 100 k protein in the cell homogenate derived from glioblasts pretreated with the drugs for 24 h. M(r) 100 k protein of glioblasts and C6 cells was immunoprecipitated by anti-elongation factor-2 (EF-2) antiserum indicating an identity or similarity in structure between the protein and EF-2. These findings provide a possibility that cell growth may be brought about through a phosphorylation of M(r) 100 k protein as one of the signal transduction processes subsequent to a mitogen stimulation.
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PMID:Stimulation by glia maturation factor of Ca(2+)-dependent phosphorylation of M(r) 100 k protein in rat glioblasts. 2050 59