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)

Clonal mouse neuroblastoma cells without tyrosine 3-monooxygenase [EC 1.14.16.2; tyrosine hydroxylase; L-tyrosine, tetrahydropteridine:oxygen oxidoreductase (3-hydroxylating)] activity were fused with normal cells from embryonic mouse sympathetic ganglia. One of the 37 hybrid cell lines obtained possesses high tyrosine 3-monooxygenase activity and synthesizes dopamine. These cells also have excitable membranes and generate action potentials in response to electrical stimuli. Thus hybrid cells, generated by fusion of neuroblastoma cells with normal cells from the nervous system, can acquire neural properties not found with the parental neuroblastoma cells.
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PMID:Neuronal properties of hybrid neuroblastoma X sympathetic ganglion cells. 0 45

Addition of dimethylsulfoxide at concentrations of 1% and 2% (vol/vol) to cells of mouse neuroblastoma clone NIE-115 in the confluent phase of growth resulted in the production of morphologically differentiated cultures with extensive process formation. Cell maintained in 2% dimethylsulfoxide remained in a stable nondividing condition for periods of up to 4 weeks. A high degree of electrical excitability was found in these cells, but there was no clear correlation of this property with the level of induction of either acetylcholinesterase (acetylcholine hydrolase; EC 3.1.1.7) or tyrosine hydroxylase [L-tyrosine, tetrahydropteridine:oxygen oxidoreductase (3-hydroxylating); EC 1.14.16.2]. In addition, intracellular levels of cyclic 3':5'-AMP were not elevated in fully morphologically and electrically differentiated cells. While cell division was markedly inhibited by 2% or higher concentrations of dimethylsulfoxide, at 1% growth continued at a somewhat slowed rate and such cultures exhibited enhanced process formation and electrical activity for a relatively short period. High concentrations (3% or 4%) of dimethylsulfoxide totally suppressed process formation and did not result in increased excitability, but cells maintained high resting potentials. The results suggest that the development of the excitable membrane in neuroblastoma cells may be expressed independently of neurospecific enzyme induction, and does not require a sustained elevation of cyclic 3':5'-AMP levels.
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PMID:Maturation of neuroblastoma cells in the presence of dimethylsulfoxide. 0 56

Previous studies indicating the importance of catecholamine metabolism in neuroblastoma were briefly reviewed. Metabolic pathways were presented showing how the major urinary metabolites 3-methoxy-4-hydroxymandelic acid (VMA) and 3-methoxy-4-hydroxy-phenylacetic acid (HVA) are formed from norepinephrine and from dopamine plus 3,4-dihydroxyphenylalanine (DOPA), respectively. For 289 neuroblastoma patients at the time of diagnosis, the urinary excretion of VMA was significantly elevated in 75%, and HVA was elevated in 80%. Periodic assay of these metabolites during the course of the disease revealed that the excretion trends were of prognostic value with 80-90% reliability. By contrast, when the excretion in only the initial urine specimens was considered, the survival rate was the same for patients with normal, and with significantly elevated, excretion. Review of the results of tracer studies aimed at elucidating the in vivo metabolic origins of the urinary metabolites suggested that a) in neuroblastoma, the catecholamines were largely inactivated by intracellular metabolism in the tumor cells; b) there was excess production and excretion of the norepinephrine precursors, DOPA and dopamine; and c) in the tumors of most neuroblastoma patients, the initial enzyme in catecholamine synthesis, tyrosine hydroxylase, had an activity comparable with that in normal adrenal glands. The importance of the metabolism of catecholamines in patients with neuroblastoma was stressed: a) The excretion of elevated levels of urinary catecholamine metabolites were useful in diagnosis and in following the course of the disease, and b) study of the catecholamine metabolism in these patients permitted examination of possible relationships between the activity of the enzymes involved in catecholamine synthesis and the malignancy of this tumor.
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PMID:Catecholamine metabolism in neuroblastoma. 1 Apr 50

The synthesis of acetylcholine, as well as catecholamines, was studied by assaying the activities of choline acetyltransferase (ChA) and tyrosine hydroxylase (TH) in the tumor tissues and the culture cells of human neuroblastoma. In the majority of 20 neuroblastomas of sympathetic origin, both ChA and TH activities were detected at a significantly high level. In the culture cells of five cell lines of human neuroblastoma, ChA activity was high, but TH was negative in four of the lines. However, it was observed that these enzyme activities changed significantly while in the long-term culture. ChA assay is a useful diagnostic test for neuroblastomas that synthesize acetylcholine. Future studies of neuroblastoma should consider cholinergic activity.
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PMID:Acetylcholine synthesis in sympathetic human neuroblastoma. 1 56

Cultured human neuroblastoma cell lines were assayed for biochemical characteristics of neuonal function. Cell lines studied included LA-N-1, LA-N-2, IMR-32, SK-N-SH, and SK-N-MC. Veratridine-dependent uptake of 22Na+ implied the presence of the action potential Na+ ionophore in LA-N-1, LA-N-2, IMR-32, and SK-N-SH. The time course of 22Na+ uptake and inhibition of uptake by tetrodotoxin supported this. SK-N-MC had no veratridine-dependent 22Na+ uptake. Tyrosine hydroxylase (EC 1.14.10.), glutamic acid decarboxylase (EC 4.1.1.15), and acetylcholine contents in neuroblastoma cells were compared to those in brain. LA-N-1 and IMR-32 contained 15 and 5 times as much tyrosine hydroxylase, respectively, whereas LA-N-2, SK-N-SH, and SK-N-MC contained only 0.5 to 5% of that in brain. Acetylcholine was present in -LA-N-2 in 15- to 20-fold greater quantities than in brain; other lines had only 10 to 50% of that in brain. None of the cell lines contained glutamic acid decarboxylase. Thus, continuously propogated human neuroblastoma cell lines may have the action potential Na+ ionophore and may be adrenergic (LA-N-1 and IMR-32), cholinergic (LA-N-2), or inactive (SK-N-SH and SK-N-MC). This is the first demonstration of the action potential Na+ ionophore and of acetylcholine production in human neuroblastoma cell lines.
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PMID:Adrenergic, cholinergic, and inactive human neuroblastoma cell lines with the action-potential Na+ ionophore. 1 22

The effect of various types of serum on morphological and biochemical changes in mouse neuroblastoma cells (clone NBP2) in culture was studied. The extent of spontaneous morphological differentiation varied markedly depending upon the type of serum and was maximal in agammaglobulin calf serum (CS). The extent of morphological differentiation after treatment of cells with cyclic AMP-stimulating agents was also dependent upon serum type and was least pronounced in fetal calf serum. The doubling time and extent of clumping varied with the type of serum. The activity of tyrosine hydroxylase (TH) in NB cells was dependent upon serum type and it was highest in newborn CS and agammaglobulin CS. Although elevation of intracellular levels of cyclic AMP in NBP2 clone invariably stimulates neurite formation and TH activity, these functions were increased in certain sera without a significant increase in the cellular cyclic AMP levels. The present study shows that neurite formation, growth rate and TH activity are regulated by more than one mode, one of which is mediated by cyclic AMP. The above changes are independently regulated in the sense that the expression of one can be increased in the absence of others.
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PMID:Modification of response of mouse neuroblastoma cells in culture by serum type. 4 11

The melanotic neuroectodermal tumor of infancy is an uncommon neoplasm typically of early childhood which has a predilection for the head and neck region, particularly the maxilla. Except for one previous example in the literature, this tumor has consistently behaved in a benign fashion. This study documents the clinical course and pathologic findings of a tumor which began in the maxilla of a 4-month-old boy, followed by a local recurrence, metastasis to a cervical lymph node and finally, widespread dissemination and death at 18 months, 24 months and 38 months, respectively. The tumor was initially composed of nests consisting of melanin-containing cells and small dark cells. An elevated vanillylmandelic acid level was recorded during the course of the disease. At autopsy, the tumor in lymph nodes, liver, bone and soft tissues had a monotonous pattern of small dark cells similar to a conventional neuroblastoma. Previous ultrastructural studies indicate that the melanotic neuroectodermal tumor of infancy is composed of melanocytes and neuroblast-like cells. Our case provided the unique opportunity to examine in sequence the ultrastructural and in vitro characteristics of a recurring and eventually metastasizing melanotic neuroectodermal tumor. Although the neuroblast-like cells were initially difficult to identify by electron microscopy, a melanin-producing cell line and a separate nonpigmented cell line were successfully isolated from various tumor explants. Various stages of melanosome development were identified in the pigmented cells from the local recurrences and in vitro. Dibutyryl cAMP accentuated the formation of pigment and dendritic development in the melanocytes and dendrites only in the small nonpigmented cells. Electron dense granules were observed in the cultured smaller cells and also in the lymph node and soft tissue metastases. Tyrosine hydroxylase activity was demonstrated in the neuroblast-like cells. In the final biopsy and autopsy material, only the neuroblast-like cells remained and the tumor resembled a conventional neuroblastoma.
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PMID:Malignant melanotic neuroectodermal tumor of infancy: a clinical, pathologic, ultrastructural and tissue culture study. 22 Oct 89

The electrical properties and the possible regulation of these properties were studied by means of intracellular microelectrode recordings in cells of mouse neuroblastoma clone N1E-115. This clone has high levels of tyrosine hydroxylase and regulates this enzyme. Cells treated for 24 h with 4 muM aminopterin followed by at least 5 days in culture developed rhythmic discharge of action potentials when superfused with phosphate-buffered saline containing less than 0.2 mM calcium or less than 0.2 mM calcium and zero potassium. This ionic excitation occurred in no cells at less than 5 days after treatment with aminopterin but at 5 days or more after treatment, 20% of cells responded to low calcium while 52% responded to low calcium and zero potassium. Concomitant with the development of a susceptibility to ionic excitation was an increase in the average resting membrane potential and morphologic maturation. This ionic excitation of cultured mouse neuroblastoma cells may be useful for studying biochemical events associated with repetitive discharge of action potentials.
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PMID:Ionic excitation of a clone of mouse neuroblastoma. 23 72

Tyrosine hydroxylase (TH) activity has been determined in 22 neuroblastoma tumors from 15 patients, in 1 pheochromocytoma, 20 adrenal glands, 10 other tumors and organs, and 4 specimens of sera. The enzyme activity was found only in the neural crest tumors and adrenal glands, but the levels were too low to be detected in the other tumors and in normal liver and kidney tissues. The average specific activity (mean +/- SE) of TH in 23 neural crest tumors was 0.559 +/- 0.101; in 20 adrenal glands was 0.418 +/- 0.124 nmol/mg protein/minute. In 13 patients with neuroblastoma and 1 patient with pheochromocytoma, both TH levels in the primary tumors and urinary excretion of vanillylmandelic acid (VMA) and homovanillic acid (HVA) were studied. The urinary excretion of VMA by 10 of 13 neuroblastoma patients and by the patient with pheochromocytoma was significantly to markedly elevated above normal levels; excretion of HVA by 12 of 13 neuroblastoma patients was similarly elevated. These results indicate that tyrosine hydroxylase, an enzyme specifically located in the adrenal medulla and monoaminergic neurons, is also present in neuroblastoma, a malignant tumor of similar embryologic origin, and in pheochromocytoma. Not only can TH activity in these tumors be demonstrated in vitro, but the elevated urinary excretion of VMA and/or HVA by the majority of patients with these tumors also indicates TH activity of the tumors in vivo.
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PMID:Studies on tyrosine hydroxylase in neuroblastoma in relation to urinary levels of catecholamine metabolites. 23 88

Catecholamine storage was examined in cultures of the murine neuroblastoma cell line, N-TD6, using histofluorescence, electron microscopic, isotopic and radioautographic criteria. This line was originally derived from uncloned, C1300 tumor cells by selection in tyrosine deficient medium. N-TD6 cells possess both tyrosine hydroxylase (tyrosine-3-monooxygenase, EC 1.14.16.2) and dopamine beta-hydroxylase (dopamine beta-monooxygenase, EC 1.14.17.1) activities. When examined for paraformaldehyde-induced histofluorescence, a small percentage of cells in the population show intense catecholamine fluorescence, often localized within discrete regions of the cellular processes. Electron microscopic examination of these cells reveals both electron lucent vesicles and more frequent, electron dense granules, 50-70 nm and 100-300 nm in diameter, respectively. The distribution of these granules and vesicles varies, but they appear most numerous near the cell surface, along processes and within process endings. By labeling cells with [3H]dopamine and then allowing the cells to release unbound label in the presence of unlabeled dopamine, the localization of catecholamine stores was visualized by radioautographic techniques. While a variety of intracellular distribution of radioactivity were observed, the most prominent concentrations were found in the processes and their terminals; no labeled material was retained when reserpine was present during uptake. The topographic coincidence of granules, catecholamine fluorescence and [3H]dopamine retention in these neuroblastoma cells suggests that catecholamines are stored within these granules in a manner analogous to that observed in normal adrenergic neurons.
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PMID:Localized catecholamine storage associated with granules in murine neuroblastoma cells. 24 Apr 85


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