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)

C1300 mouse neuroblastoma cells gradually accumulate lipofuscin-like pigment when they are maintained in culture. Pigment was demonstrated by positive straining for acid phosphatase and with periodic acid-Schiff stain. Pigment was formation in cells was reduced by exposure of the cells to lower doses of dihydroergotoxine mesylate which also induced neurite formation and increased protein synthesis. Since lipofuscin appears to originate as a result of wear and tear within the cells, the drug probably exerts its beneficial effects by reducing the rate of intracellular wear and tear associated with aging.
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PMID:Effects of dihydroergotoxine mesylate on aging neurons in vitro. 2 79

Exposure of mouse neuroblastoma cells in culture to low pH for 8 days caused a sixfold increase in cell lipofuscin pigment. Pigment content was measured as the percent of cells having clumps of acid phosphatase-staining material. Hydergine, between 0.1 and 3 microgram/ml, caused a concentration-related decrease in pigment content. Hydergine also stimulated neurite formation in cells in regular pH medium and was slightly toxic to cells in low pH medium. These results support the use of neuroblastoma cells as an in vitro model for age pigment studies.
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PMID:Effects of hydergine on aging neuroblastoma cells in culture. 64 6

Infectious scrapie prions are composed largely, if not entirely, of an abnormal isoform of the prion protein (PrP) designated PrPSc. In scrapie-infected mouse neuroblastoma (ScN2a) and hamster brain (ScHaB) cells, PrPSc accumulates primarily within the cell cytoplasm, whereas cellular PrP (PrPC) is anchored to the external surface of the plasma membrane by a glycoinositol phospholipid moiety. To determine the subcellular localization of PrPSc, scrapie-infected cells were grown to approximately 75% confluency, fixed briefly, and then incubated with guanidine thiocyanate before antibody staining and examination by electron microscopy. PrPSc immunoreactivity was enhanced by denaturation with guanidine isothiocyanate which also permeabilized cells (Taraboulos et al., J Cell Biol 110:2117, 1990). As judged both by deposition of immunoperoxidase reaction product (diaminobenzidine) and by presence of immunogold particles, PrPSc was identified in discrete vesicular foci and some large bodies in the cytoplasm of scrapie-infected cells. Some vesicles with PrPSc staining also contained myelin figures resembling those found in autophagic vacuoles forming secondary lysosomes. The presence of PrPSc in secondary lysosomes is inferred from colocalization of guanidine isothiocyanate enhanced PrP immunoreactivity and acid phosphatase. Neither the diaminobenzidine reaction product nor immunogold particles were observed in association with the nucleus, endoplasmic reticulum, or Golgi stacks. Exposure of scrapie-infected cells to the brefeldin A dispersed the Golgi apparatus but did not alter the morphologic distribution of PrPSc, indicating that no detectable PrPSc was associated with Golgi stacks. It remains to be established whether secondary lysosomes are involved in the post-translational formation of PrPSc.
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PMID:Ultrastructural localization of scrapie prion proteins in cytoplasmic vesicles of infected cultured cells. 168 1

We report a 16-year-old boy with esthesioneuroblastoma that presented with a unilateral tumor extending to the maxillary sinus and periorbital region. Despite initial therapy with gross resection, 5,682 cGy to the tumor bed and chemotherapy, the patient subsequently had a rapid local recurrence with distant metastases. Immunocytochemical, ultrastructural, cytogenetic, and molecular techniques were performed to determine if this tumor was biologically similar to childhood neuroblastoma. Urinary excretion of vanillylmandelic acid (VMA) and homovanillic acid (HVA) were markedly elevated. Chromogranin and neuron specific enolase immunostaining of tumor cells was positive, as seen in neuroblastoma. Electron microscopic studies showed cells that were closely packed and connected by occasional cell junctions. The cell cytoplasm contained moderate amounts of filaments and microtubules. Numerous electron dense granules were observed; however, these granules lacked distinct nucleoids and generally reacted strongly for acid phosphatase, indicating a lysosomal rather than a secretory function. Tumor cells contained near-pseudotetraploid chromosomes, with all chromosomes represented at least three times, and chromosome 5 was present in multiples of eight. Clonal structural abnormalities included 2q+ and 5q+ and multiple double minutes. Northern blot analysis revealed both c-myc and N-myc expression; however, N-myc amplification was not demonstrated, and c-myc expression appeared increased, unlike cases of rapidly progressive neuroblastoma. These results suggest that despite biologic similarities to neuroblastoma in catecholamine excretion and some ultrastructural features, molecular genetic abnormalities differ in this comparatively aggressive case of estesioneuroblastoma.
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PMID:Cytogenetic and molecular evaluation of clinically aggressive esthesioneuroblastoma. 202 81

We have studied the regulation of lysosomal glycosidases during morphological differentiation of NB2a neuroblastoma cells. Cells treated with dibutyryl cAMP induced axon-like neuritis and showed a 2-4 fold increase in the activity of 6 lysosomal glycosidases, reaching their highest level after 5 days of treatment. Cells treated with retinoic acid, which induced dendrite-like neurites, did not show significant changes in the glycosidases activity although cell proliferation was also inhibited. There was no change in the pattern of the enzyme secretion during the dibutyryl cAMP treatment and morphological analysis using electron microscopy and cytochemical staining with acid phosphatase indicated the presence of lysosomes in the induced neurites.
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PMID:Induction of lysosomal glycosidases by dibutyryl cAMP in neuroblastoma cells. 242 67

The effect of prolonged exposure to ammonia on fluid-phase, receptor-mediated, and adsorptive (non specific) endocytosis in cultured neuroblastoma (Neuro-2a) cells were studied using fluorescein-labeled dextran, concanavalin A conjugated with fluorescein isothiocyanate, and cationized ferritin as tracers. Ammonia treatment increased the rate of endocytosis of cationized ferritin as well as the number of cell elements involved in the process. Moreover, the number of cytoplasmic components containing acid phosphatase activity was also found to increase following ammonia treatment. In contrast, flow-cytometric analyses showed that, under experimental conditions, exposure to ammonia did not alter the intralysosomal pH and had little effect on the fluid-phase and receptor-mediated endocytosis of fluorescein-labeled dextran and concanavalin-A fluorocrome, respectively.
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PMID:Effects of prolonged exposure to ammonia on fluid-phase, receptor-mediated, and adsorptive (non specific) endocytosis in cultured neuroblastoma cells. A flow-cytometry and cytochemical study. 244 72

The method is suggested to isolate simultaneously microsomes and plasma membranes of neuroblastoma S 1300 N 18 cells by means of differential centrifugation in the step density gradient of Percoll/Ficoll with a high degree of purification determined from the activity of marker enzymes (acetyl cholinesterase Na+,K+-ATPase, alkali phosphatase, glucose-6-phosphatase, succinate-dehydrogenase, acid phosphatase) as well as from the content of DNA and RNA and with a sufficiently high protein yield. The purified fractions of microsomes and plasma membranes are established to contain no phosphatidyl glycerol and cardiolipin--safety markers of mitochondrial membrane purification. A degree of separation of microsomes, plasma membranes and proteins dissolved in cytosol may be estimated by the activity of the cholesterol-synthesizing system of enzymes with the use of sterol-transferring protein.
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PMID:[Rapid simultaneous isolation of microsomes and plasma membranes from neuroblastoma C 1300 N 18 cells]. 258 50

Opioid receptor activity in neuroblastoma x glioma NG108-15 hybrid cell membranes was attenuated by acid phosphatase purified by high performance liquid chromatography and devoid of protease activity. Treatment of membranes with this phosphatase decreased opioid inhibition of adenylate cyclase and this effect was potentiated by the presence of the opioid agonist during the phosphatase treatment. Phosphatase treatment did not affect the number of opioid receptors but it did alter the distribution of receptors among affinity states, by increasing the percentage of receptors in the low affinity state. The similarities between these effects and desensitization of the opioid receptor, during chronic opioid treatment, are discussed.
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PMID:Modification of opioid receptor activity by acid phosphatase in neuroblastoma x glioma NG108-15 hybrid cells. 283 85

The nature of red fluorescent particles in vitally acridine orange stained C 1300 neuroblastoma monolayer cells was evaluated by electron microscopy, cytofluorometry, cytopharmacological and cell fractionation studies. At the ultrastructural level the distribution of red fluorescent granules correlated with that of the Golgi complex and Golgi derived structures during various stages of differentiation, mitosis, and under colcemid treatment. Cytopharmacological studies revealed that red fluorescence was displaced in a concentration and time dependent manner with the basic drugs chloroquine and quinacrine. Subcellular fractionation studies showed that acridine orange was concentrated in fractions that also contained the highest amount of acid phosphatase and electron dense vesicles. Vital acridine orange staining of neuroblastoma cells in culture can give information on the relationship between Golgi-derived vesicles and cell functions like proliferation and differentiation. The influence of drugs on these processes can be studied.
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PMID:Further studies on the nature of red fluorescent structures in neuroblastoma monolayer cells vitally stained with acridine orange. 615 46

The present study examines the endocytosis of conjugates of horseradish peroxidase (HRP) with ricin and wheat germ agglutinin (WGA) in rat adrenal pheochromocytoma cells (PC 12 line) cultured in the absence of nerve growth factor (NGF). In these cells acid phosphatase (ACPase) activity is not confined to a single cisterna and vesicles at the transaspect (mature face) of the Golgi apparatus which correspond to GERL of cultured neurons, neuroblastoma and other cell types. But ACPase is found in several cisternae of the Golgi apparatus as well as in lysosomes. On the other hand, thiamine pyrophosphatase activity, is found in a typical location within two or three cisternae of the Golgi apparatus near its transaspect. Following adsorptive endocytosis of HRP-labelled lectins (ricin-HRP or WGA-HRP) into PC12 cells, a reaction product is seen in dense bodies as well as in small vesicles and tubules throughout the cytoplasm, at the periphery of large vacuoles, in smooth and coated vesicles and tubules near the Golgi apparatus and in anastomosing tubules. The cisternae of the Golgi apparatus are not involved in the endocytosis of lectin-HRP. We conclude that in PC12 cells grown without NGF, unlike the case of cultured neurons and neuroblastoma cells, GERL is not segregated from the Golgi apparatus by either ACPase cytochemistry, or by the functional criterion of endocytosis of lectin-HRP conjugates.
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PMID:In 'undifferentiated' PC12 cells, GERL is not segregated from the Golgi apparatus. 617 35


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