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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Six new cell lines have been established from human neuroblastomas. Cell line SMS-KAN, from primary tumor before therapy, and line SMS-KANR, from bone marrow after chemotherapy and radiotherapy, were established from the same patient. Cell lines SMS-KCN (from primary tumor before any therapy) and SMS-KCNR (from bone marrow after chemotherapy) were established from another patient. Two other lines (SMS-MSN and SMS-SAN) were established from different patients before any therapy was given. Cell lines established from recurrent disease after chemotherapy (SMS-KANR and SMS-KCNR) had significantly shorter doubling times and increased plating efficiencies compared to those of cell lines derived from the same patient before chemotherapy (SMS-KAN and SMS-KCN). All cell lines contained tyrosine hydroxylase, aromatic L-amino acid decarboxylase, and dopamine-beta-hydroxylase. Measurable amounts of choline acetyltransferase were also detected in SMS-KAN and SMS-KANR. Karyotype analysis showed all cell lines except SMS-MSN to be pseudodiploid with modal numbers of 46 and deletions of the short arm of chromosome 1; SMS-MSN had a modal number of 57-58 chromosomes. All cell lines had double-minute chromosomes, except SMS-KANR, which had abnormally banding regions. These new cell lines provide in vitro models of neuroblastoma suitable for the study of differences in neuroblastoma cell populations before chemotherapy as compared to the cell populations that proliferate after therapy.
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PMID:Characterization of human neuroblastoma cell lines established before and after therapy. 345 56

A selection procedure was devised for neurons and related cells that depends upon the ability of the cells to synthesize certain amine neurotransmitters. The rationale for selection is that tyrosine is an essential amino acid for most mammalian cells and that three enzymes from mammalian sources can catalyze the synthesis of tyrosine: phenylalanine hydroxylase (EC 1.14.16.1), tyrosine hydroxylase (EC 1.14.16.2), and tryptophan hydroxylase (EC 1.14.16.4). Tyrosine hydroxylase is found predominantly in adrenergic neurons and related cells that synthesize dopamine, norepinephrine, and epinephrine, and tryptophan hydroxylase in cells synthesizing serotonin or melatonin. Only 1 out of 70,000 uncloned mouse neuroblastoma cells grew well in the absence of tyrosine. Approximately 50% of the cell lines obtained by selection had tyrosine hydroxylase activity. This selection procedure thus provides a simple means of obtaining cell lines of neural origin on the basis of their ability to synthesize putative transmitters.
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PMID:Selection for neuroblastoma cells that synthesize certain transmitters. 415 49

Mouse neuroblastoma cells (clone neuro-2A) in the undifferentiated and "differentiated" form were compared by light and electron microscopy. "Cytodifferentiation" was induced in monolayer cultures by the addition of dibutyryl-cyclic AMP. The pattern of concanavalin A binding sites was studied after coupling with horseradish peroxidase. The following major differences were observed. The differentiated cells are characterized by numerous and long neurites, aggregation of ribosomes into polysomes, an extensive network of neurofilaments and microtubules, many dense-core neurosecretory-like vesicles, a discontinuous pattern of concanavalin A binding sites on the plasma membrane, and an increase of the specific activities of acetylcholinesterase, choline acetylase and tyrosine hydroxylase. In contrast, the undifferentiated cells grown in suspension culture lack neurites, contain dispersed ribosomes, infrequent neurofilaments and microtubules and dense-core neurosecretory-like vesicles, and exhibit a continuous pattern of concanavalin A binding sites. In addition, the specific activities of the above mentioned enzymes are significantly lower.
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PMID:The undifferentiated and extended forms of C1300 murine neuroblastoma. An ultrastructural study and detection of concanavalin A binding sites on the plasma membrane. 415 21

Neuroblastoma clones were examined for choline acetyltransferase (EC 2.3.1.6), tyrosine hydroxylase (EC 1.14.3.a), acetylcholinesterase (EC 3.1.1.7), and also for neurite formation. One clone does not form axons or dendrites. Three types of clones were found with respect to neurotransmitter synthesis: cholinergic, adrenergic, and clones that do not synthesize acetylcholine or catechols. All clones contain acetylcholinesterase. These results show that genes determining neurotransmitter species can be expressed in dividing cells, that the parental programs of gene expression are inherited, and that dividing cells can be programmed with respect to their ability to communicate with other cells.
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PMID:Neurotransmitter synthesis by neuroblastoma clones (neuroblast differentiation-cell culture-choline acetyltransferase-acetylcholinesterase-tyrosine hydroxylase-axons-dendrites). 440 Feb 94

Mouse neuroblastoma cells in culture have been used as a model for the study of the mechanism by which activities of tyrosine hydroxylase (EC 1.14.3.a) are regulated in sympathetic tissue. The activity of tyrosine hydroxylase in cultured cells drops to barely detectable activities after 1 week and remains low for months in culture in the uncloned cell line of neuroblastoma. Activity in an adrenergic clone isolated from the uncloned line has about 20% of the activity of the fresh grated tumor cell. N(6), O(2')-dibutyryl adenosine 3':5'-cyclic monophosphate causes a concentration and time-dependent increase in enzyme activity in both the cloned and uncloned cell lines. Enzyme activity is elevated by other stable analogs of adenosine 3':5'-cyclic monophosphate, notably the N(6)-monobutyryl, 8-aminomethyl, and 8-methylthio derivatives of the cyclic nucleotide; by the inhibitor of cyclic nucleotide phosphodiesterase, papaverine; and by sodium butyrate. Changes in cell morphology and tyrosine hydroxylase activity are shown not to be necessarily related.
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PMID:Regulation of tyrosine hydroxylase activity in cultured mouse neuroblastoma cells: elevation induced by analogs of adenosine 3':5'-cyclic monophosphate. 440 8

Clonal lines of neurons were obtained in culture from a mouse neuroblastoma. The neuroblastoma cells were adapted to culture growth by the animal-culture alternate passage technique and cloned after single-cell plating. The clonal lines retained the ability to form tumors when injected back into mice. A striking morphological change was observed in the cells adapted to culture growth; they appeared as mature neurons, while the cells of the tumor appeared as immature neuroblasts. Acetylcholinesterase and the enzymes for the synthesis of neurotransmitters, cholineacetylase and tyrosine hydroxylase were assayed in the tumor and compared with brain levels; tyrosine hydroxylase was found to be particularly high, as described previously in human neuroblastomas. The three enzymes were found in the clonal cultures at levels comparable to those found in the tumors. Similarly, there were no remarkable differences between the three clones examined.
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PMID:Establishment of functional clonal lines of neurons from mouse neuroblastoma. 526 16

Cyclic AMP and glucocorticoids appear to have a role in regulating the activity of tyrosine hydroxylase (TH), as well as the expression of "morphological differentiation" in murine neuroblastoma. Monolayer cultures of C-1300 murine neuroblastoma (clone NBP2) were treated with the following compounds in ethanol: dexamethasone, triamcinolone acetonide, hydrocortisone, cortexolone, androstenedione, testosterone, estradiol-17 beta; or with the phosphodiesterase inhibitor Ro20-1724 [4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone]. Treatment with either 200 micrograms/ml Ro20-1724 or 50 micrograms/ml dexamethasone produced significant increases in TH activity compared to alcohol controls (1.44 vs. 0.82 nmol 14CO2/mg protein/hr compared to 0.095). Triamcinolone acetonide or hydrocortisone also produced smaller, but significant, increases in TH activity compared to dexamethasone. When steroid activities were compared at 25 microM concentration and after 60 min of incubation (to maximize TH activity), triamcinolone acetonide was not as effective (62%) as dexamethasone. The relatively inactive glucocorticoid cortexolone produced a slight but significant increase, while the androgens androstenedione and testosterone and the estrogen estradiol-17 beta were without effect.
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PMID:Glucocorticoids increase tyrosine hydroxylase activity in cultured murine neuroblastoma. 611 72

Feedback inhibition of tyrosine hydroxylase by catechols was evaluated using in situ and in vitro enzyme assays. The three catechol compounds used were norepinephrine, 2-hydroxyestradiol, and 3'4'-dihydroxy-2-methylpropiophenone (U-0521, Upjohn); representing endogenous catecholamines, catechol estrogens, and a synthetic catechol, respectively. The in situ experiments were performed with dissociated retinal cells from rats and with stationary phase adrenergic-like neuroblastoma cells (N1E-115). The catechol estrogen, 2-hydroxyestradiol, resembled the endogenous catecholamine in its potency to inhibit in vitro and in situ tyrosine hydroxylations with IC50 values of 10 microM in vitro and 100 microM in situ. The drug U-0521, which has been used as an inhibitor of catechol-O-methyltransferase (COMT), was also found to be an inhibitor of tyrosine hydroxylase. Further, it was shown to be more potent than the natural catechols, both in vitro and in situ, with IC50 values of 30--600 nM.
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PMID:A comparison of 2-hydroxyestradiol and U-0521 (3'4'-dihydroxy-2-methylpropiophenone, Upjohn) as in situ and in vitro inhibitors of tyrosine hydroxylase. 612 Oct 5

The DOPA-content in neuroblastoma clone N1E-115 is higher than the dopamine or noradrenaline content. Blockade of tyrosine hydroxylase by alpha-methyl-p-tyrosine (1 X 10(-3) M) resulted in a decrease of cellular DOPA-content to 24.9% after 4 hr. The accumulation of DOPA in these cells which is probably due to limited activity of l-aromatic amino acid decarboxylase led us to use DOPA-content as a measure of tyrosine hydroxylase (TH) activity. Dopamine and especially apomorphine were effective at low concentrations (dopamine IC50 1 X 10(-5) M, apomorphine 2 X 10(-7) M); lisuride had no effect on TH-activity. The low effective dose of apomorphine and the failure of lisuride to influence TH-activity are comparable to the observations in striatal synaptosomal preparations and make the N1E-115 clone a suitable model for studying the mechanism of TH-regulation. However, since haloperidol (1 X 10(-5) M) did not reverse the apomorphine-induced blockade of TH, a receptor-mediated blockade of TH seems to be improbable.
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PMID:Mouse neuroblastoma clone N1E-115: a suitable model for studying the action of dopamine agonists of tyrosine hydroxylase activity. 612 55

The neuroblastoma line SK-N-SH-SY5Y (SY5Y) is a thrice subcloned nearly diploid clonal line of human origin. When grown in 15% fetal calf serum in Ham's F-12 medium as herein described, SY5Y has neuroblast-like properties in its undifferentiated state. Treatment with nerve growth factor results in morphological and physiological differentiation not unlike that elicited by nerve growth factor in sympathetic ganglia primary cultures. Careful examination of catecholamine synthesizing enzyme specific activities and catecholamine concentrations in nerve growth factor-treated SY5Y cells showed a small elevation of tyrosine hydroxylase, no change in dopamine-beta-hydroxylase or in dopamine or norepinephrine intracellular concentrations. This is consistent with the interpretation that nerve growth factor acts as a permissive or trophic factor, and not necessarily as an instructive or specifying factor in this system.
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PMID:Effect of nerve growth factor on catecholamine metabolism in a human neuroblastoma clone (SY5Y). 613 Sep 33


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