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)

An immuno-electron microscopic study performed by a pre-embedding peroxidase-antiperoxidase (PAP) technique revealed S-100 protein reactivity in the cytoplasm and connecting processes of marginal cells of olfactory neuroblastomas. The overlapping cytoplasmic processes of S-100 immunoreactive cells completely surrounded the main membrane-bound granule-bearing tumor cells forming a continuous interface between those tumor cells and fibrous connective tissue. The S-100 immunoreactivity was also observed in the cytoplasm and processes on non-membrane-bound granule-bearing tumor cells within the tumor nodule. The tumor cell nodules and isolated tumor cells were completely surrounded by basement membrane material stainable with anti-laminin antiserum. It appears that the membrane-bound granule-bearing tumor cells of olfactory neuroblastoma are partitioned by basement membrane of S-100 protein-reactive cells and their processes. No S-100 protein-reactive cells were observed within the olfactory epithelium of the two patients with olfactory neuroblastoma. To determine a possible origin of S-100 protein-positive cells, normal olfactory epithelium from six adult patients at autopsy was studied for S-100 reactivity. There were no S-100 protein-positive cells within the normal olfactory epithelium. We discuss the evidence for considering olfactory neuroblastoma a variant of paraganglioma.
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PMID:Olfactory neuroblastoma: an immuno-electron microscopic study of S-100 protein-positive cells. 352 97

Translation in vitro of membrane-bound polyribosomal mRNAs from rat brain has shown several to be developmentally regulated [Hall & Lim (1981) Biochem. J. 196, 327-336]. Here we describe the isolation and characterization of cDNAs corresponding to two such brain mRNAs. One cDNA (M444) hybrid-selected a 0.95 kb mRNA directing the synthesis in vitro of a 21 kDa pI-6.3 polypeptide, which was processed in vitro by microsomal membranes. A second cDNA (M1622) hybridized to a 2.2 kb mRNA directing the synthesis of a 55 kDa pI-5.8 polypeptide. Both mRNAs were specific to membrane-bound polyribosomes. Restriction maps of the corresponding genomic DNA sequences are consistent with both being single copy. The two mRNAs were present in astrocytic and neuronal cultures, but not in liver or spleen or in neuroblastoma or glioma cells. The two mRNAs were differently regulated during brain development. In the developing forebrain there was a gradual and sustained increase in M444 mRNA during the first 3 weeks post partum, whereas M1622 mRNA appeared earlier and showed no further increase after day 10. In the cerebellum the developmental increase in M444 mRNA was biphasic. After a small initial increase there was a decrease in this mRNA at day 10, coincident with high amounts of M1622 mRNA. This was followed by a second, larger, increase in M444 mRNA, when amounts of M1622 mRNA were constant. The contrasting changes in these two mRNAs in the developing cerebellum are of particular interest, since they occur during an intensive period of cell proliferation, migration and altering neural connectivity. As these mRNAs are specific to differentiated neural tissue, they represent useful molecular markers for studying brain differentiation.
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PMID:Expression and developmental regulation of two unique mRNAs specific to brain membrane-bound polyribosomes. 366 28

The effects of dopamine agonists and antagonists were investigated in human neuroblastoma (HNB) tissue culture cell lines and correlated with the presence of specific membrane-bound dopamine-binding activity ("receptor"). In four HNB cell lines the dopamine antagonists domperidone, pimozide, and spiroperidol inhibited macromolecular synthesis in vitro as indicated by decreased 3H-TdR and 14C-leu incorporation in a dose-response fashion with at least 50% inhibition noted at 10(-6)M concentration of each drug. Dopamine agonists showed no significant inhibition. Scatchard analysis of competitive dopamine-binding assays in all four HNB cell lines and in five of eight solid tumors obtained at surgery demonstrated high affinity, limited-capacity binding consistent with a single class of receptor sites with receptor concentrations (Rc) ranging from 8.8 to 26.7 pmol/gm wet weight of tissue with dissociation constants (KD) from 0.40 to 6.6 nmol/L, compared with a mean Rc of 28.1 +/- 5.2 pmol/gm wet weight of tissue and KD = 0.38 +/- 0.09 nmol/L in receptor-rich dog caudate nucleus, the normal dopamine-sensitive control. Survival was prolonged after inoculation of the SK-N-AS cell line into nude mice and subsequent domperidone administration by 50% (24 days after drug initiation versus 16 days in control mice). These data demonstrate inhibition of macromolecular synthesis in HNB by dopamine antagonists and suggest that dopamine receptor is associated with this inhibition. The determination of dopamine receptors may prove useful in the selection of dopamine antagonists as specific chemotherapy for patients with neuroblastoma.
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PMID:Inhibition of human neuroblastoma by dopamine antagonists. 402 14

The guanine nucleotides GDP, GTP, and guanosine-5'-(beta, gamma-imido)triphosphate inhibit binding of opiates and opioid peptides to receptors solubilized from membranes of neuroblastoma X glioma NG108-15 hybrid cells. The inhibition reflects decreased affinity of receptors for opioid ligands. Whereas in membranes, only opioid agonist binding is sensitive to guanine nucleotide inhibition, both agonist and antagonist binding is reduced in the case of soluble receptors. Furthermore, soluble receptors are more sensitive to the effects of guanine nucleotides than are membrane-bound receptors. These observations are consistent with the suggestion that solubilized receptors may be complexes of an opiate binding protein and a guanine nucleotide-sensitive regulatory component.
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PMID:Guanine nucleotides inhibit binding of agonists and antagonists to soluble opiate receptors. 625 76

The calcium binding protein calmodulin and the opiate receptor binding sites are unevenly distributed in various subcellular fractions of neuroblastoma-glioma NG108-15 cells. The crude mitochondrial-membrane fraction of these cells contains two membrane fractions that are separable by sucrose gradient centrifugation. These two differ in the content of both calmodulin and opiate receptors. Leucine enkephalin and D-Ala2-methionine enkephalinamide decrease the amount of membrane-bound calmodulin in the NC108-15 cells in a time- and dose-dependent manner, whereas the opiate antagonists naloxone and levallorphan have an opposite effect. Naloxone blocks the effect of leucine enkephalin and dextrallorphan has no significant effect. The opiate alkaloids entorphine and phenazocine induce changes similar to that of the enkephalins whereas morphine is inactive even at high concentrations. The alteration in the amount of membrane-bound calmodulin after a short incubation (15 min) with the enkephalins or with naloxone is reflected as an opposite change in the amount of calmodulin in the cell cytosol. Naloxone and levallorphan also increase the number of opiate receptors in NG108-15 cells but dextrallorphan has no such effect. Modulation of the intracellular distribution of calmodulin by opioid peptides and alkaloids may control the activity of various membrane-bound and cytosolic systems that are calmodulin- and/or calcium-dependent.
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PMID:Enkephalins and opiate antagonists control calmodulin distribution in neuroblastoma-glioma cells. 629 49

The pumping activity of the plasma membrane-bound Na+,K+-ATPase shows considerable variation during the cell cycle of mouse neuroblastoma Neuro-2A cells. Addition of external ATP at millimolar concentrations, which selectively enhances the plasma membrane permeability of Neuro-2A cells for sodium ions, stimulates the Na+,K+-ATPase pumping activity at all phases of the cell cycle from a factor of 1.05 in mitosis up to 2.2 in G1 phase. Determination of the number of Na+,K+-ATPase copies per cell by direct 3H-ouabain binding studies in the presence of external ATP shows a gradual increase in the number of pump sites on passing from mitosis to the late S/G2-phase by approximately a factor of 2. From these data the pumping activity per copy of Na+,K+-ATPase, optimally stimulated with respect to its various substrate ions, has been determined during the various phases of the cell cycle. This optimally stimulated pumping activity per enzyme copy, which is a reflection of the physicochemical state of the plasma membrane, is high in mitosis, almost twofold lower in early G1 phase, and increases gradually again during the other phases of the cell cycle. This shows that the observed regulation of Na+,K+-ATPase activity during the cell cycle is caused by a combination of three independent factors--namely variation in intracellular substrate availability (Na+), changes in number of enzyme copies per cell, and modulation of the plasma membrane environment of the protein molecules. The modulation of the optimal pumping activity per enzyme copy shows a good correlation (rho = 0.96) with the known modulation of protein lateral mobility during the cell cycle, such that a high protein lateral mobility correlates with a low enzyme activity. It is concluded that changes in plasma membrane properties take place during the Neuro-2A cell cycle that result in changes in the rate of protein lateral diffusion and Na+,K+-ATPase activity in directly correlated way.
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PMID:Membrane regulation of the Na+,K+-ATPase during the neuroblastoma cell cycle: correlation with protein lateral mobility. 630 15

Degradation of tritiated [Leu5]enkephalin was studied in cultures of neuroblastoma cells (clone N1E-115). Incubation of cells in suspension revealed Tyr as the main tritiated metabolite; however, Tyr-Gly-Gly and Tyr-Gly were detectable as well. In a crude membrane preparation of the neuroblastoma cells the level of Tyr is reduced to 13% and that of Tyr-Gly to 10% of the initial value, whereas Tyr-Gly-Gly is increased to about 5 times the initial value. Of the degraded enkephalin, 66% was accounted for by the formation of Tyr, 30% by the formation of Tyr-Gly-Gly and 4% by the formation of Tyr-Gly. The production of Tyr was inhibited by bestatin, an inhibitor of aminopeptidases, and that of Tyr-Gly-Gly by captopril, an inhibitor of angiotensin-converting-enzyme. The results prove the ability of neuroblastoma cells (N1E-115) to degrade enkephalin by aminopeptidase and the membrane-bound angiotensin-converting-enzyme.
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PMID:Enkephalin degradation by enkephalinergic neuroblastoma cells. Involvement of angiotensin-converting-enzyme. 632 31

In neuroblastoma N1E 115 cells, carbachol, histamine and PGE1 elevated cyclic GMP content and, induced the efflux of preloaded 45Ca2+, the release of membrane-bound Ca2+ measured by fluorescent CTC, and the increase in [Ca2+]i as measured by Quin 2 fluorescence. The time course of the responses, the absolute requirement of extracellular Ca2+, the inhibition by receptor blockers, and the concentration dependency on histamine were all similar between these responses. The observation indicates that the mobilization of Ca2+, especially the increase of [Ca2+]i, may be intimately linked to the synthesis of cyclic GMP in the cells.
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PMID:Receptor-mediated regulation of calcium mobilization and cyclic GMP synthesis in neuroblastoma cells. 633 50

We present the first case report of an olfactory neuroblastoma (esthesioneuroblastoma) diagnosed by cytologic examination. The patient was a 40-year-old male who had a 13-year history of "adenocarcinoma" of the nasal cavity until the correct diagnosis of olfactory neuroblastoma was made cytologically from pleural fluid shortly before his death. The cells had the typical features of rosette formation, scanty elongated cytoplasm, clustering of cells and nuclear compression resulting in an "onion-skin" appearance. Surgical specimens, several biopsies and fine needle aspiration of a metastatic deposit in a lymph node all showed, retrospectively, features of esthesioneuroblastoma. Electron microscopy showed membrane-bound dense-core secretory granules. Autopsy findings revealed multiple metastases but no tumor at the original site; that tumor had been treated with high-dose radiation therapy as well as systemic chemotherapy. Olfactory neuroblastoma is a rare tumor, but it is important to recognize because it has a better prognosis than the more commonly encountered malignancies of the nose.
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PMID:Cytologic diagnosis of olfactory neuroblastoma. Report of a case with multiple diagnostic parameters. 657 48

C-1300 murine neuroblastoma ( MNB ) contains the catecholamine biosynthetic pathway. This study investigated manipulation of this pathway for effects on cell growth and survival in tumor-bearing mice, and to correlate these findings with specific membrane-bound dopamine-binding activity. The dopamine antagonists domperidone, pimozide, and spiroperidol inhibited macromolecular synthesis in vitro as demonstrated by decreased [3H]TdR and [14C]leu incorporation in a dose-response fashion; 56, 49, and 43% inhibition was noted at 10(-6) M concentration of each drug, respectively, with no loss of cell viability. Dopamine agonists showed no significant inhibition. Scatchard analysis of dopamine binding was consistent with a single class of receptor sites with a mean concentration of 13.2 +/- 2.0 pmole/g wet weight of tissue and mean dissociation constant (Kd) = 0.69 +/- 0.38 nM, compared to a mean receptor concentration of 28.1 +/- 5.2 pmole/g wet weight of tissue and Kd = 0.38 +/- 0.09 nM in receptor-rich dog caudate nucleus, the normal control. A/J mice injected with 1 X 10(6) tumor cells and treated with daily pimozide or domperidone had a significant increase in disease-free survival when compared to controls (15 versus 8.5 days, P less than 0.001) as well as a significant increase in overall survival (35 versus 25 days, P less than 0.001). These data suggest that dopamine antagonists inhibit macromolecular synthesis in the C-1300 MNB . The inhibition of MNB tumor growth in vivo by dopamine antagonists suggests a specific chemotherapeutic approach to neuroblastoma, possibly mediated by dopamine receptors.
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PMID:Inhibition of murine neuroblastoma growth by dopamine antagonists. 672 21


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