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Query: UMLS:C0027819 (
neuroblastoma
)
27,800
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Immunocytochemical, immunoblotting and in situ hybridization studies were used to map the distribution of SNAP-25 protein and mRNA in the rodent nervous system. These experiments demonstrated that subsets of neurons expressed SNAP-25, and that several patterns of expression emerged: SNAP-25 expression in caudate nucleus was initially concentrated in axons, which subsequently was localized in presynaptic regions of these axons. Other regions, typified by neocortex, showed developmental increases and persistent adult neuronal immunoreactivity for SNAP-25. Finally, olfactory bulb contained neurons which initially expressed SNAP-25, but lost expression during maturation. Additional studies in cultured human and rat cell lines derived from neural crest suggested that SNAP-25 is expressed in such lines, but not in glial or fibroblast lines. Differentiation of rat PC-12 cells with nerve growth factor failed to alter steady-state levels of SNAP-25 protein; similar responses were seen in human SMS-KCNR
neuroblastoma
cells differentiated using
retinoic acid
. The presence of SNAP-25 in presynaptic regions of numerous neuronal subsets and in neural crest cell lines suggests that this protein subserves an important function in neuronal tissues.
...
PMID:Distribution and expression of SNAP-25 immunoreactivity in rat brain, rat PC-12 cells and human SMS-KCNR neuroblastoma cells. 157 61
A comparable pattern of morphological neuronal differentiation was induced in the human
neuroblastoma
cell line SMS-KCNR by treatment with either
retinoic acid
(RA) or exogenous laminin (LM). LM expression and synthesis by SMS-KCNR was increased upon RA treatment which involved the cell bound, rather than the secreted protein. These data suggest an involvement of LM in the
neuroblastoma
differentiation process manifested both as an ability of LM to induce a morphological neuronal differentiation and as a selective control on LM metabolism during RA induced neuronal differentiation.
...
PMID:Modulation of laminin synthesis in human neuroblastoma cells during retinoic acid induced differentiation. 159 74
We report the expression of different interleukins (IL) in four human glioblastoma and
neuroblastoma
cell lines. The glioblastoma cell line LI, expresses IL-1 beta and IL-6 mRNA, though not IL-2 and IL-4. The expression of the former gene is modulated by
retinoic acid
. Two cell clones [BE(2)-C and BE(2)-M17] as well as the
neuroblastoma
cell line SK-N-BE(2), from which both clones were derived, express IL-6 mRNA, but not IL-1 beta, IL-2 or IL-4. Both IL-1 beta and IL-6 cytokines are known to increase hypothalamic CRH mRNA, a gene reported to be expressed in all these cell lines. The production of both cytokines and neuropeptides indicates a complex dialogue between tumour cells and anti-tumour immunity.
...
PMID:Interleukin-1 beta and interleukin-6 mRNA are expressed in human glioblastoma and neuroblastoma cells respectively. 160 28
The Childrens Cancer Study Group evaluated daily oral 13-cis-
retinoic acid
to determine its therapeutic efficacy in 28 children with advanced
neuroblastoma
refractory to conventional therapy. Cheilitis and fissured lips were the most common side effects; however, fewer than 50% of the patients experienced any toxicity. Two of twenty-two evaluable children demonstrated positive response to therapy. In one case, a child received the drug for 11 months. Seventeen patients demonstrated progressive disease within 28 days of the start of treatment. Three other patients with stable disease, or removed from study at day 28, were considered nonresponsive. Our data demonstrate that, when given as a single daily oral dose of 100 mg/m2, 13-cis-
retinoic acid
does not have significant activity in children with advanced
neuroblastoma
.
...
PMID:13-cis-retinoic acid (NSC 122758) in the treatment of children with metastatic neuroblastoma unresponsive to conventional chemotherapy: report from the Childrens Cancer Study Group. 160 52
The effect of a complex in vitro synthesized extracellular matrix (ECM) and its components on growth and phenotypical differentiation of a human
neuroblastoma
(NB) cell line (HTLA230) was investigated. Rat smooth-muscle-cell (R22CIF)-derived ECM composed of collagen, glycoproteins, and glycosaminoglycans (GAGs) promoted spontaneous neurite outgrowth of HTLA230 cells but did not alter their growth kinetic or cloning efficiency as compared with cells seeded onto gelatin-coated dishes. The matrix significantly enhanced, quantitatively and qualitatively, the responsiveness of HTLA230 cells to
retinoic acid
(RA), and a substantially reduced growth rate was observed in the presence of RA with cells grown on the ECM. Biochemical modification of the composition of the R22CIF-matrix by trypsin digestion and/or high-salt extraction (4 M guanidinium) demonstrated that the ratio of chondroitin sulfate to hyaluronic acid (HA) present in the ECM determines the capacity of the matrix to promote NB differentiation. A human fibroblast (T-1)-derived ECM, which has a biochemical composition of the GAG component similar to that of the trypsinized R22CIF-matrix, but which has a high amount of glycoproteins, confirmed these results. Nerve-growth-factor (NGF)-induced differentiation in a variant HTLA 230 cell line was inhibited when cells were grown on an ECM with a low ratio of chondroitin sulfate/HA. The composition of the ECM thus modulates the responsiveness to various differentiation-inducing agents and alters the phenotype of NB cells.
...
PMID:Modulation of neuroblastoma cell differentiation by the extracellular matrix. 161 81
The electrophysiological properties of a human
neuroblastoma
cell line, LA-N-5, were studied with the whole-cell configuration of the patch clamp technique before and after the induction of differentiation by
retinoic acid
, a vitamin A metabolite. Action potentials could be elicited from current clamped cells before the induction of differentiation, suggesting that some neuroblasts of the developing sympathetic nervous system are excitable. The action potential upstroke was carried by a sodium conductance, which was composed of two types of sodium currents, described by their sensitivity to tetrodotoxin (TTX) as TTX sensitive and TTX resistant. TTX-sensitive and TTX-resistant sodium currents were blocked by nanomolar and micromolar concentrations of TTX, respectively. The voltage sensitivity of activation and inactivation of TTX-resistant sodium current is shifted -10 to -30 mV relative to TTX-sensitive sodium current, suggesting that TTX-resistant sodium current could play a role in the initiation of action potentials. TTX-sensitive current comprised greater than 80% of the total sodium current in undifferentiated LA-N-5 cells. The surface density of total sodium current increased from 24.9 to 57.8 microA/microF after cells were induced to differentiate. The increase in total sodium current density was significant (P less than 0.05). The surface density of TTX-resistant sodium current did not change significantly during differentiation, from which we conclude that an increase in TTX-sensitive sodium current underlies the increase in total current.
...
PMID:Sodium currents during differentiation in a human neuroblastoma cell line. 164 94
Retinoic acid
is a naturally occurring metabolite of vitamin A that influences the differentiation of a variety of neural cells in vitro. In the LA-N-1 human
neuroblastoma
line,
retinoic acid
treatment increases the binding of nerve growth factor (Bmax). The purpose of this study was to examine the effects of
retinoic acid
on PC12 rat pheochromocytoma, a neural crest-derived cell line that can be induced to express a sympathetic neuroblast-like phenotype by nerve growth factor treatment. In contrast to the differentiating effects of nerve growth factor,
retinoic acid
treatment of PC12 cells had a negligible effect on cellular morphology. However, treatment with
retinoic acid
enhanced the survival of PC12 cells following oxidative injury generated by H2O2 treatment in a manner that is qualitatively similar to that observed after nerve growth factor treatment. Also, there was an increase in 125I-nerve growth factor binding activity in solubilized PC12 membrane preparations derived from
retinoic acid
-treated PC12 cells. These data suggest that
retinoic acid
may play a role in neuronal development and in neuronal injury by stimulating the ability of neurons to cope with oxidative stress and/or by enhancing neuronal responsiveness to trophic factors such as the nerve growth factor.
...
PMID:Antioxidant effect of retinoic acid on PC12 rat pheochromocytoma. 164 45
The morphological change of several
neuroblastoma
cell lines induced by griseolic acid, a novel and potent inhibitor of cyclic nucleotide phosphodiesterase (PDE), was examined. In the cell lines tested, Neuro-2a (a murine
neuroblastoma
cell line) showed dose-dependent (1 microM-1 mM) neurite extension. Griseolic acid markedly increased the intracellular cyclic AMP level of Neuro-2a cells, suppressed DNA synthesis (82% at 1 mM), and induced multipolar (multiple-neurite-bearing)-type neuritogenesis. A similar type of neurite outgrowth was induced by 8-bromo-cyclic AMP, which also elevated the intracellular cyclic AMP concentration. In contrast, when Neuro-2a cells were treated with
retinoic acid
, neurite formation was of the monopolar (single-neurite-bearing) type. Papaverine and theophylline, which have been frequently used as PDE inhibitors, failed to induce these morphological changes up to 1 mM, probably owing to the lesser potency of these compounds as compared with griseolic acid on the inhibition of PDE.
Retinoic acid
, theophylline, and papaverine were ineffective at elevating the intracellular cyclic AMP level. These results suggest that multipolar-type cell shape change in Neuro-2a cells is correlated with the accumulation of intracellular cyclic AMP and that griseolic acid is a useful compound to induce
neuroblastoma
cells into terminal differentiation.
...
PMID:Multiple neurite formation in neuroblastoma cell lines by griseolic acid, a potent inhibitor of cyclic nucleotide phosphodiesterases. 164 54
Cultured human
neuroblastoma
(GOTO) cells were induced to differentiate by dibutyryl cyclic AMP (Bt2cAMP) and/or
retinoic acid
(RA). A combination of Bt2cAMP (1 mM) and RA (1 microM) yielded the most significant networks of neurites after 3 to 4 days, this being associated with the reduction of N-myc mRNA levels. Next, we examined several cellular genes that were possibly linked with changes in N-myc gene expression under these conditions. Among the genes examined, both nucleolin and a major heat-shock protein (hsp70) mRNAs showed changes concomitant with those in N-myc mRNA levels when induced by Bt2cAMP and RA. Dibutyryl cAMP alone induced several short cellular processes and caused a marked decrease in N-myc mRNA within 2 days. RA alone induced a few long and straight neurites along the longitudinal axis of individual cells and a significant decrease in growth rate but showed neither network formation nor a decrease in N-myc gene expression. These results indicate differential effects of Bt2cAMP and RA on the regulatory mechanisms of both cell proliferation and differentiation and also indicate a possible association of expression of N-myc gene with those of hsp70 and nucleolin genes.
...
PMID:Down modulation of N-myc, heat-shock protein 70, and nucleolin during the differentiation of human neuroblastoma cells. 165 99
Retinoids are known to have profound effects on cellular differentiation and embryo pattern formation. In the adult organism, retinoid acid (RA) receptors are present in a large variety of tissues, including brain. However, little is known of the precise roles of RA at these different sites. In the present study we have identified a novel potential target of RA action by identifying an RA response element (RARE) in the human oxytocin (OT) gene promoter. We have used DNA-mediated gene transfer techniques to introduce various portions of the OT 5'-flanking sequences next to the chloramphenicol acetyltransferase (CAT) gene in
neuroblastoma
cells. RA elicited a marked stimulation of the transcriptional activity of the OT promoter in cells cotransfected with either the human RA receptor alpha, beta, or gamma. In cells cotransfected with the RA receptor alpha, the ED50 of this response was 5 x 10(-10) M. The RA response could also be conferred to a heterologous promoter independent of orientation. 5'-Deletions as well as site-directed mutations demonstrated that four TGACC motifs, located at -162, -156, -103, and -83 in the OT promoter, are necessary for optimal RA induction. Mutation or deletion of any of these elements reduces significantly the RA response. Interestingly, the first two TGACC motifs overlap with the estrogen response element that we have previously characterized in this gene. Furthermore, the TGACC motif located at -83 overlaps with the CCAAT box. We further demonstrate that in
neuroblastoma
cells transfected with an RAR alpha expression vector expression of the endogenous OT gene is stimulated greater than 4-fold in response to RA. Our studies constitute the first report of a RARE in a neuropeptide gene and define a mechanism by which OT gene expression can be modulated by
retinoic acid
.
...
PMID:Identification of a retinoic acid response element in the human oxytocin promoter. 165 67
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