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 prognosis of patients with advanced neuroblastoma remains poor despite recent progress in chemo/radiotherapy. Therapeutic trials on the induction of differentiation of neuroblastoma by chemical and biological agents have been attempted to improve patients' prognosis. Recently a new synthetic polyprenoic acid, E5166, having retinoic acid properties, has been described. In this study two human neuroblastoma cell lines, KP-N-RT(LN) and SK-N-DZ, were treated in vitro by E5166. Morphological differentiation of KP-N-RT(LN) and SK-N-DZ cells could be induced by E5166 in the presence of 1.7 X 10(-5) M E5166 for 10 days in culture. Levels of catecholamines (dopamine, adrenaline, and noradrenaline) were not elevated in the E5166-differentiated cells. E5166-induced differentiation may not be cyclic AMP dependent, since levels of cyclic AMP did not increase after exposure of cells to this agent. No significant increase in neuron-specific enolase levels could be demonstrated in E5166-treated neuroblastoma as compared to control untreated cells. E5166 treatment of KP-N-RT(LN) and SK-N-DZ cells was found to inhibit colony formation in soft agar in a dose-dependent manner. Colonies of KP-N-RT(LN) cells in the presence of E5166 showed morphological differentiation as defined by the expression of long neurite processes. E5166 is a less toxic reagent than the retinoic acids used for the induction of differentiation, it can be administered to patients p.o., and the concentration of E5166 which induces the morphological differentiation in vitro can be achievable in vivo. Therefore our study suggests that E5166 could be a useful therapeutic agent in advanced neuroblastoma to differentiate residual anaplastic tumor cells to a benign form (ganglioneuroma) after surgery and chemotherapy.
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PMID:Morphological differentiation of human neuroblastoma cell lines by a new synthetic polyprenoic acid (E5166). 282 May 69

The regulation of cytoplasmic pH (pHi) was examined in neuroblastoma X glioma hybrid cell-line cells (NG108-15 cells) using 2,7-biscarboxyethyl-5(6)-carboxyfluorescein. The pHi of NG108-15 cells suspended in nominally HCO-3-free, Na+-containing buffer could be reduced by the external application of acetate. The recovery of pHi to its resting value was blocked by the removal of extracellular Na+, by the addition of extra-cellular H+, and by the addition of analogs of amiloride selective for inhibition of Na+/H+ exchange. The rate of recovery of pHi from acid load exhibited an ionic selectivity of Na+ greater than Li+ much greater than K+, and no recovery was observed in N-methyl-D-glucamine+. Tetrodotoxin and 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid had no effect on early pHi recovery. These data suggest that Na+/H+ exchange accounts primarily for the recovery of pHi in NG108-15 cells under our experimental conditions. Na+/H+ exchange in NG108-15 cells was accelerated by alpha 2-adrenergic receptors. Thus, (-)epinephrine, but not (+)epinephrine, elicited an intracellular alkalinization which was blocked by the alpha 2-adrenergic receptor selective antagonist yohimbine but not by the alpha 1-adrenergic receptor antagonist, prazosin, nor the beta-adrenergic antagonist, propranolol. Norepinephrine, clonidine, and the clonidine analog, UK-14304, also caused alkalinization of NG108-15 cells, whereas isoproterenol, a beta-adrenergic receptor agonist, and phenylephrine, a selective alpha 1-adrenergic receptor agonist, did not. Manipulations that blocked Na+/H+ exchange blocked the ability of alpha 2-adrenergic agonists to alkalinize the interior of NG108-15 cells without blocking the ability of these agonists to attenuate cAMP accumulation. These findings provide the first direct evidence of modulation of Na+/H+ exchange activity by a receptor linked to inhibition of adenylate cyclase and offer a possible mechanism whereby alpha 2-adrenergic receptors might influence cellular activity apart from changes in cyclic nucleotide metabolism.
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PMID:Alpha 2-adrenergic receptors accelerate Na+/H+ exchange in neuroblastoma X glioma cells. 288 87

Apamin is a toxic polypeptide extracted from bee venom. It has been considered as a neurotoxin with central action, but its low concentrations (10(-8)-10(-7) M) were shown to reversibly block the nonadrenergic inhibition and effects of externally applied ATP, noradrenaline and caffeine in smooth muscles of the gastrointestinal tract. All these processes are related to the activation of Ca-dependent potassium permeability. Current-clamp, voltage-clamp and patch-clamp experiments have also shown that apamin blocks specifically some types of these conductances in other tissues: skeletal muscles, mammalian neurons and neuroblastoma, hepatocytes. Nowadays apamin is the most specific but not a universal blocker of the Ca-activated potassium conductance.
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PMID:[Apamin--a highly specific and effective blockader of calcium-dependent potassium conductance]. 307 68

Human neuroblastoma cells (clone SHSY-5Y) induced to differentiate by 12-O-tetradecanoylphorbol-13-acetate (TPA) are shown to possess properties characteristic of mature ganglion cells. Elevation of the external K+ concentration, exposure to Ca2+ ionophore A23187, and acetylcholine all stimulate the release of preloaded 3H-noradrenaline in the presence but not in the absence of added Ca2+. Acetylcholine causes a fall in the 86Rb+ or 14C-TPMP equilibrium potential across the plasma membrane and stimulates 86Rb+ efflux. These responses are prevented by atropine. Acetylcholine and muscarine but not nicotine stimulate an increase in 45Ca2+ influx, an effect blocked by atropine. None of these responses have been observed in nondifferentiating cells. Muscarinic receptors, however, as measured by the binding of tritiated quinuclidinyl benzilate (3H-QNB), were present to a similar extent in control and differentiated cells. Both cell types also exhibit an accelerated release of Ca2+ in response to acetylcholine, but the control cells were at least 1 order of magnitude more sensitive to the agonist.
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PMID:Development of a neural phenotype in differentiating ganglion cell-derived human neuroblastoma cells. 309 56

Clinical and biological significance of increased urinary excretion of dopamine in Japanese children with neuroblastoma was investigated. There was an increase in dopamine excretion in 19 of 29 patients (66%) and 15 of 19 in stages III and IV (79%). When the ratio of noradrenaline and dopamine was divided into two at the value of 3.5 x 10(-2), the disease-free survival rate was four of 16 (25%) in the low ratio group and nine of 19 (69%) in the high ratio group. In five patients, the urinary analysis revealed that only the level of dopamine was elevated before initiation of the therapy. The common features of these patients were as follows: (1) the age at diagnosis was 1 to 4 years; (2) all originated from the suprarenal region; (3) stages were advanced III or IV; and (4) the prognosis was poor. N-myc oncogene of the primary tumor was evident in three, and all were amplified to 32, 37, and 112 copies. These observations suggested that the immaturity of catecholamine metabolism may correlate to the poor prognosis and that "dopaminergic neuroblastoma" may be a clinical subentity of poor prognostic neuroblastoma.
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PMID:Dopaminergic neuroblastoma as a poor prognostic subgroup. 338 88

The clinical manifestations of 253 neuroblastoma cases in childhood, treated in Denmark from 1943 to 1980, were reviewed. Most striking was the vagueness of symptoms in the majority of patients, only a few of whom exhibited the symptoms strongly suggestive of a neuroblastoma (i.e. the Horner syndrome, the watery diarrhoea syndrome, the dancing eye syndrome). The vagueness of the symptoms might have led to fatal procrastination of the diagnosis. The diagnostic delay has, however, no independent prognostic significance for survival in our patients (p = 0.09). The maximal tumour spread was recorded for all 253 patients, and the distribution of metastases was in accordance with the "soil-seed" hypothesis. The tumour spreads with equal frequency by local growth, by lymphatic vessels to distant lymph nodes, and by blood to bone. Only in widely disseminated tumours are metastases to the lungs, the meninges, the brain, and the reproductive organs seen to occur. Eighty-five percent of the patients, for whom data were available, excreted VMA above the normal value for their age, and 43% excreted Norepinephrine + Epinephrine (N + E) above normal levels. The excretion of both VMA and N + E was significantly correlated to stage, and thus to prognosis. Neither the level of VMA excretion nor the level of N + E had any bearing on the survival when age and stage were adjusted for. Serial VMA and N + E determinations show that patients with normal values for these parameters had significantly better prognosis than patients with elevated values during the first, second, third and fourth trimesters after the initiation of treatment. Increasing values in the individual patient were associated with a poor prognosis. We found no correlation between the initial leucocyte count and survival when age and stage were adjusted for.
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PMID:Signs, symptoms, metastatic spread and metabolic behavior of neuroblastomas treated in Denmark during the period 1943-1980. 363 7

Two neuroblastoma cell lines established from tumor tissue taken from one individual are described. The first of these was established from a bone marrow aspirate (RT-BM) and the other from a right axillary lymph node (RT-LN) of a 1-yr 2-mo-old patient with Stage IV disease. The original lines were cloned in soft agar to yield six clones of the bone marrow-derived line (RT-BM 1-6) and 12 of the lymph node line (RT-LN 1-12). Chromosomal analysis of the original lines and clones showed they all have either identical or very similar karyotypes, with a deletion of chromosome 1p. Transmission electron microscopy indicates all contain neurosecretory (dense core) granules and neurotubules. In addition catecholamine metabolites of dopamine and noradrenaline have been identified. Different growth characteristics of the lymph node and bone marrow lines have been identified. RT-LN lines grow in a single cell layer with neurite processes, whereas bone marrow-derived lines form focal aggregates with neurite processes. In addition the colony-plating efficiency of the lymph node-derived lines is higher than those derived from bone marrow. Comparison of the cell surface antigen profile of the original tumor tissue, parent lines, and clones demonstrates they all bind seven of a panel of nine monoclonal antibodies. The expression of these antigens has remained stable in vitro for 25 passages undertaken over a 2-yr period. The definition of antigens that are expressed on the membranes of neuroblastoma cells in a stable form can aid in the differential diagnosis of neuroblastoma from other "small round cell tumors of childhood" and hopefully contribute to a greater understanding of the biology of this highly malignant tumor.
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PMID:Identical expression of cell surface membrane antigens on two parent and eighteen cloned cell lines derived from two different neuroblastoma metastases of the same patient. 373 Nov 24

The amounts of vanillylmandelic acid (VMA), homovanillic acid (HVA), and catecholamines (adrenaline, noradrenaline, and dopamine) in 24-hr urine specimens of 10 infants with neuroblastoma detected through mass screening in Sapporo City (patient group) were compared with those of 24 healthy infants (control group). The ages of the infants of both groups ranged from 6 to 11 months, which agrees with the age when mass screening is performed. For VMA and HVA, the mean value plus two or three times the standard deviation of the control group clearly separated the two groups in the units of mg/day, microgram/mg of creatinine, mg/kg/day, and mg/m2/day. The cut off values of 24 micrograms/mg of creatinine for VMA and 25 micrograms/mg of creatinine for HVA are now being used by us for assaying 24-hr urine specimens. No significant difference was found between the groups in levels of catecholamines, but their data were thought to be useful as normal values, since few published data regarding their normal values are available.
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PMID:Vanillylmandelic acid, homovanillic acid, and catecholamines in urine of infants with neuroblastoma 6- to 11-month-old. 379 31

Fusaric acid, an inhibitor of dopamine beta-hydroxylase, which converts dopamine to noradrenaline, lowered the blood pressure and induced a subjective improvement in patients with phaeochromocytoma. These effects may be due either to an impairment of catecholamine biosynthesis or to a direct action on the blood vessels. The use of this drug in the treatment of patients with inoperable malignant phaeochromocytoma or neuroblastoma may improve symptoms and prolong survival.
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PMID:Effect of fusaric acid (a dopamine beta-hydroxylase inhibitor) on phaeochromocytoma. 398 67

Adenylate cyclase (EC 4.6.1.1) activity was stimulated by low concentrations of dopamine and apomorphine, but not by low concentrations of norepinephrine in homogenates of malignant mouse neuroblastoma cells. In cyclic AMP-induced "differentiated" cells, dopamine concentration required for a maximal increase in adenylate cyclase activity was about 10-fold less than that required for a similar increase in control cells, and norepinephrine-sensitive adenylate cyclase activity became apparent at low norepinephrine concentrations. The pharmacological properties of dopamine-sensitive adenylate cyclase were different from those of norepinephrine-sensitive enzyme. For example, dopamine-stimulated adenylate cyclase activity was markedly reduced by low concentrations of haloperidol and phentolamine, whereas norepinephrine-stimulated enzyme activity required higher concentrations of these blocking agents for a similar amount of inhibition. Norepinephrine-stimulated enzyme activity was markedly blocked by low concentrations of propranolol, whereas dopamine-stimulated enzyme activity required a much higher concentration of this blocking agent for a similar amount of inhibition. Low concentrations of isoproterenol increased adenylate cyclase activity in malignant cells, but in "differentiated" cells even a high concentration failed to do so. The fact that dopamine and norepinephrine produced an additive stimulatory effect on adenylate cyclase activity suggests that they interact at different receptor sites. This suggestion is further supported by the observation that the combination of prostaglandin E(1) and norepinephrine produced an additive stimulatory effect of enzyme activity. The observation that the effects of dopamine and prostaglandin E(1) are not additive, coupled with the observation that a low concentration of phentolamine blocked the effect of prostaglandin E(1), suggests that these two agents may interact at a common site.
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PMID:Demonstration of dopamine-sensitive adenylate cyclase in malignant neuroblastoma cells and change in sensitivity of adenylate cyclase to catecholamines in "differentiated" cells. 436 72


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