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 possible role of surface glycosaminoglycans (GAGs) in neuronal maturation occuring in neuroblastoma cultures has been investigated. GAGs of neuroblastoma cells, grown in suspension and monolayer, were labelled with 3H-glucosamine and 35S-sulfate. Neuron maturation, following cell adhesion to culture dishes, is accompanied by an increased ability of the cells to retain heparan sulfate (HS) on their surface, which is otherwise lost into the culture medium. The role of surface HS as a cofactor of cellular differentiation is discussed.
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PMID:Surface glycosaminoglycans as a differentiation cofactor in neuroblastoma cell cultures. 13

C-1300 murine neuroblastoma cells release glycoproteins into the culture medium. The process was studied by prelabeling spinner cultures for 12 to 60 hours with [3H]glucosamine. Then, the medium was removed and replaced with fresh medium lacking radioactive isotope. Soluble material released into the medium during the subsequent 2-hour incubation was collected by trichloroacetic acid precipitation. The released proteins were then separated by discontinuous polyacrylamide gel electrophoresis in buffers containing sodium dodecyl sulfate. The electrophoretograms of glycoproteins obtained from cultures labeled for different lengths of time were very similar; three major radioactive regions centered about molecular weights 87,000, 66,000, and 55,000 were present. When spinner cells were transferred to monolayer culture in the presence of N6,O2' dibutyryl adenosine 3':5'-monophosphate (Bt2cAMP), differentiation (extension of neurites twice the diameter of the perikaryon) was observed. Monolayer cultures grown in the presence of Bt2cAMP and [3H]glucosamine for 12 hours released glycoproteins which gave a gel electrophoresis pattern similar to that obtained using spinner cultures. However, after 60 hours in the presence of Bt2cAMP and [3H]glucosamine, the released radioactive material consisted almost exclusively of glycoproteins of the 66,000 molecular weight class. Similar results were obtained if [3H]fucose was substituted for [3H]glucosamine, or if bromodeoxyuridine (which also induced differentiation) was substituted for Bt2cAMP. Similar experiments using radioactive amino acids were conducted with both spinner and monolayer cultures. Much of the released radioactive material was contained in the same three molecular weight classes as the glycoproteins released by spinner cells prelabeled with [3H]glucosamine, and this pattern did not vary with length of labeling period or type of culture. These results may imply that the glycosylation of released proteins is influenced by agents which can induce differentiation. The origin of this released material is discussed. [3H]Glucosamine-labeled glycoproteins of the molecular weight class centered about 55,000 (discussed above) were isolated by preparative gel electrophoresis. They co-migrated with authentic mouse brain microtubular protein as two closely spaced bands on a number of different electrophoretic systems. This protein fraction was also characterized as complexing with a monospecific antitubulin antibody.
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PMID:Glycoproteins released into the culture medium of differentiating murine neuroblastoma cells. 17 7

When mouse neuroblastoma clonal cell line N4TG1 cells were cultured in the presence of opiates or enkephalins, in the range 10(-6)-10(-10) M for 24 hr, a dose-dependent inhibition of the incorporation of [3H]glucosamine and [14C]-galactose into sialoglycosphingolipids and glycoproteins was observed. The gangliosides most affected comigrated in thinlayer chromatographic systems with GM2 (GalNAc[AcNeu]-Gal-Glc-ceramide), GM1 (Gal-GalNAc[AcNeu]Gal-Glc-ceramide), and GDla (AcNeu-Gal-GalNAc[AcNeu]Gal-Glc-ceramide). The effects were stereospecific and naloxone-reversible. Polyacrylamide gel electrophoresis revealed that the synthesis of a large number of membrane glycoproteins was also stereospecifically inhibited. Synthesis of other proteins and glycoproteins, proteoglycans, DNA, and membrane phospholipids and the rate of cell division were not altered in any specific or stereospecific manner. Moreover, clonal cell lines (neuroblastomas and oligodendroglioma) and human skin fibroblasts, which do not possess opiate receptors, did not respond to opiates or enkephalins in a stereospecific manner.
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PMID:Opiates and enkephalins inhibit synthesis of gangliosides and membrane glycoproteins in mouse neuroblastoma cell line N4TG1. 21 11

Ionic currents induced by 5-hydroxytryptamine (5-HT) in cultured neuroblastoma N18 cells were studied using whole-cell voltage clamp. The response was blocked by 1-10 nM 5-HT3 receptor-specific antagonists MDL 7222 or ICS 205-930, but not by 1 microM 5-HT1/5-HT2 receptor antagonist spiperone or 5-HT2 receptor-specific antagonist ketanserin. These 5-HT3 receptors seem to be ligand-gated channels because the response (a) did not require internal ATP or GTP, (b) persisted with long internal dialysis of CsF (90 mM), A1F4- (100 microM), or GTP gamma S (100 microM), and (c) with ionophoretic delivery of 5-HT developed with a delay of less than 10 ms and rose to a peak in 34-130 ms. Fluctuation analysis yielded an apparent single-channel conductance of 593 fS. The relative permeabilities of the channel for a variety of ions were determined from reversal potentials. The channel was only weakly selective among small cations, with permeability ratios PX/PNa of 1.22, 1.10, 1.01, 1.00, and 0.99 for Cs+, K+, Li+, Na+, and Rb+, and 1.12, 0.79, and 0.73 for Ca2+, Ba2+, and Mg2+ (when studied in mixtures of 20 mM divalent ions and 120 mM N-methyl-D-glucamine). Apparent permeability ratios for the divalent ions decreased as the concentration of divalent ions was increased. Small monovalent organic cations were highly permeant. Large organic cations such as Tris and glucosamine were measurably permeant with permeability ratios of 0.20 and 0.08, and N-methyl-D-glucamine was almost impermeant. Small anions, NO3-, Cl-, and F-, were slightly permeant with permeability ratios of 0.08, 0.04, and 0.03. The results indicate that the open 5-HT3 receptor channel has an effective minimum circular pore size of 7.6 A and that ionic interactions in the channel may involve negative charges near the pore mouth.
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PMID:Ion permeation through 5-hydroxytryptamine-gated channels in neuroblastoma N18 cells. 228 32

A panel of seven murine monoclonal antibodies reactive with human hepatocellular carcinoma (HCC) cell line, SK- HEP-1, resulted in the definition of four distinct antigen systems, designated HB4, HB5, HB1 and HJ2. HB4 antigen was found to be expressed specifically on HCC cell lines and fresh HCC specimens but not on normal liver. Immunoprecipitation tests suggest that the HB4 epitope may be a heat-stable carbohydrate determinant on a high molecular mass molecule. HB5 antigen was found to have less-restricted expression on a panel of normal adult tissues and on melanoma, astrocytoma, sarcoma, neuroblastoma and epithelial cancer cell lines. In fetal and adult liver, HB5 antigen localized to bile canaliculi and ducts. Under reducing conditions, three mAbs detected a Mr 140,000 glycoprotein using lysates of [125-I], [3-H]-glucosamine and [35-S]-methionine labeled SK-HEP-1 cells. Under non-reducing conditions an additional component of greater than Mr 200,000 was also detected. HB1 antigen was found on almost all monolayer cell lines and not on most cultured suspension cells. This antigen was also detected on cultured HCC cells inoculated into nu/nu mice. Immunoprecipitation experiments revealed that the HB1 antigen is a bimolecular complex with an Mr 170,000 alpha chain and Mr 130,000 beta chain under non-reducing conditions, and three subunits of Mr 140,000, Mr 30,000 and Mr 130,000 under reducing conditions. Two antibodies reacted with epitopes on the alpha chain. HJ2 antigenic determinant is a heat-stable component which could not be immunoprecipitated. This most widely expressed antigen was found in secreted form in many of the cells and tissues examined. These antibodies introduce new antigens which may serve as useful markers for the diagnosis, classification and investigation of HCC and other liver diseases.
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PMID:Serological analysis and biochemical characterization of monoclonal antibodies defining antigens of human hepatocellular carcinoma. 255 3

The specific interaction of the cytolytic Clostridium perfringens delta toxin with membrane GM2 was indicated by: (i) characterization of this glycolipid in the membrane of sheep and goat erythrocytes, which are lysed by the toxin, whereas GM2 was undetectable in insensitive rabbit erythrocytes, (ii) demonstration of 125I-toxin binding to GM2, by autoradiography, following incubation with thin-layer chromatograms containing separated neuroblastoma gangliosides, and (iii) toxin fixation by phospholipid-cholesterol unilamellar vesicles containing either sheep gangliosides or GM2. In order to investigate the intramembrane events leading to membrane disruption following toxin binding, the photoreactive probe 12(4-azido-2-nitrophenoxy)stearoyl 1-14C glucosamine, which inserts into the outer layer and labels integral membrane proteins, was used to establish whether delta toxin penetrates into target cell membrane. No toxin labeling was found, suggesting that toxin action takes place at the membrane surface. This contention is supported by the observation that despite toxin binding, GM2 liposomes did not release entrapped 14C-glucose. Treatment of toxin with carboxypeptidases, but not aminopeptidases, abolished both toxin binding capacity onto erythrocytes and its combination with antitoxin neutralizing antibodies, suggesting that the carboxy terminal end of the toxin is critical for binding to cell membrane.
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PMID:Interaction of Clostridium perfringens delta toxin with erythrocyte and liposome membranes and relation with the specific binding to the ganglioside GM2. 255 36

P-glycoprotein is a plasma membrane protein believed to mediate resistance to natural product drugs such as vincristine, Adriamycin, and actinomycin D. To facilitate the study of human P-glycoprotein, monoclonal antibodies (designated HYB-612, HYB-241, and HYB-195) were raised against vincristine-resistant human neuroblastoma (SH-SY5Y/VCR) cells. The antibodies recognize a Mr 180,000 plasma membrane phosphoglycoprotein produced in increased amounts in SH-SY5Y/VCR as well as in vincristine-resistant human neuroepithelioma (MC-IXC/VCR), vinblastine-resistant human leukemia (CEM/VLB100), and actinomycin D- or vincristine-resistant Chinese hamster (DC-3F/AD X and DC-3F/VCRd-5L) cells, as compared to control cells. Radioimmunoprecipitation of proteins in cells metabolically labeled with [35S]methionine, 32Pi, or [3H]glucosamine and Western transfer procedures were used for these studies. Characterization of the HYB-612 or HYB-241 antigen by destructive degradation produced a pattern of results typical of a conformation-dependent protein epitope. HYB-612 recognizes complexes of the Mr 180,000 antigen with an iodinated photoaffinity analogue of vinblastine or with tritiated azidopine. Furthermore, pretreatment of MC-IXC and MC-IXC/VCR cells with HYB-612 or HYB-241 before measurement of tritium-labeled actinomycin D or vincristine uptake increases the amount of drug accumulation in resistant, but not in sensitive, cells. Of importance is the fact that the Mr 180,000 protein is expressed in cells which also contain a Mr 170,000 P-glycoprotein. The relative amounts of the Mr 180,000 and 170,000 species vary from one drug-resistant cell line to another. Evidence that the Mr 180,000 protein is a P-glycoprotein and that there is a conserved complex pattern of resistance-related surface proteins in multidrug-resistant cells is presented in this report.
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PMID:Characterization of monoclonal antibodies recognizing a Mr 180,000 P-glycoprotein: differential expression of the Mr 180,000 and Mr 170,000 P-glycoproteins in multidrug-resistant human tumor cells. 256 79

The molecular mechanism of opiate receptor down-regulation and desensitization was investigated by studying the effects of cycloheximide and tunicamycin on opiate receptor activities in neuroblastoma X glioma NG108-15 hybrid cells. Cycloheximide inhibited [35S]methionine and [3H]-glucosamine incorporation by hybrid cells, while tunicamycin inhibited [3H]glucosamine incorporation only. Exposing hybrid cells to these two agents did not alter the viability of the cell. Treatment of NG108-15 cells with cycloheximide or tunicamycin produced a decrease in [3H]diprenorphine binding dependent on both time and concentrations of inhibitors, with no measurable modification in the ability of etorphine to regulate intracellular cyclic AMP production. Cycloheximide attenuated [3H]-diprenorphine binding by decreasing both the number of sites, Bmax, and the affinity of the receptor, Kd. Tunicamycin treatment produced a decrease in Bmax with no apparent alteration in Kd values. Cycloheximide and tunicamycin did not potentiate the rate or magnitude of etorphine-induced down-regulation or desensitization of opiate receptor in NG108-15 cells. Furthermore, there was an apparent antagonism in cycloheximide action on receptor down-regulation. The reappearance of opiate binding sites after agonist removal was affected by these two inhibitors. Cycloheximide and tunicamycin eliminated the increase in [3H]diprenorphine binding in the chronic etorphine-treated cells after agonist removal. These two inhibitors did not alter the resensitization of hybrid cells to etorphine. Thus, the site of opiate agonist action to induce receptor down-regulation and desensitization is not at the site of protein synthesis or protein glycosylation. These data substantiate previously reported observations that receptor down-regulation and receptor desensitization are two different cellular adaptation processes.
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PMID:Effects of cycloheximide and tunicamycin on opiate receptor activities in neuroblastoma X glioma NG108-15 hybrid cells. 298 31

To study the properties of protein-bound oligosaccharides in neuronally differentiating cells, two model systems were used: murine N1E-115 and N-18 neuroblastoma cells inducible by serum starvation and rat PC12 pheochromocytoma cells inducible by nerve growth factor. Glycopeptides were prepared from cells metabolically labeled with [3H]glucosamine and analyzed by gel filtration. The properties of the high-molecular-weight glycopeptides were studied using enzymatic digestion with neuraminidase and endo-beta-galactosidase. In contrast to other cell lines analyzed, the neuroblastoma and pheochromocytoma lines contained predominantly glycopeptides completely cleavable with endo-beta-galactosidase, which indicated that they were linear-type poly-N-acetyllactosamine glycans. The proportion of these linear chains in the high-molecular-weight fraction increased during neuronal differentiation in both cell systems. The linear nature of the glycans was also correlated with positive anti-i and negative anti-I reactivity of the cells in immunofluorescence microscopy. Specific cell surface labeling for poly-N-acetyllactosamine glycans and sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed several glycoprotein components, some of which showed changes during neuronal differentiation. The high proportion of linear poly-N-acetyllactosamine chains in these neuronal cell lines and its increase during neuronal differentiation suggests that these glycans may be a characteristic feature of neuronal or neuronally differentiating cells.
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PMID:Poly-N-acetyllactosamine glycans of cellular glycoproteins: predominance of linear chains in mouse neuroblastoma and rat pheochromocytoma cell lines. 330 6

Cell surface glycoproteins of mitotic neuroblastoma cells and cells differentiated by prostaglandin cyclic adenosine monophosphate treatment were quantified by flow cytometric analysis and specific fluorescent lectins. No differences in fluorescent lectin binding were seen between suspensions of mitotically active and differentiated N2AB-1 cells following exposure to either fluorescein (FL)-labeled soy bean agglutinin (FL-SBA) specific for N acetyl galactosamine or FL-concanavalin A (FL-CON A) which binds to mannose residues. These lectins, however, were shown to bind specifically to these cells as revealed by competitive blocking studies with hapten sugars. When FL Ulex europaeus (FL-UEA) specific for fucose was reacted with control or differentiated cells, no binding was seen even with an increased dose of lectin before or after enzyme treatment. However, differentiated N2AB-1 cells, reacted with FL-wheat germ agglutinin (FL-WGA) specific for N acetyl glucosamine, bound more FL-WGA than that seen for control cultures. Furthermore, specific sites for FL-WGA were shown to be saturable and were lost upon pretreatment of cells with neuraminidase. Neuraminidase pretreatment revealed masked sites for FL-CON A and FL-SBA since binding was increased at least twofold for these lectins on mitotic and differentiated cells. These data indicate that single cell measurements of surface glycoproteins can be made on living neural cells and that differentiation induces an increase in cell surface N-acetyl glucosamine residues.
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PMID:Surface glycoproteins of differentiating neuroblastoma cells analyzed by lectin binding and flow cytometry. 366 75


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