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)

Machado-Joseph disease (MJD)/spinocerebellar ataxia type 3 (SCA3) is an autosomal dominant spinocerebellar degeneration characterized by a wide range of clinical manifestations. The molecular mechanisms underlying the selective neuronal death typical of MJD/SCA3 are unknown. In this study, human SK-N-SH neuroblastoma cells stably transfected with full-length MJD with 78 CAG repeats were assayed for the dynamic expression of Hsp27, known as a suppressor of poly-Q mediated cell death, in the presence of mutant ataxin-3 in different passages of cultured cells. A dramatic decrease of Hsp27 expression was observed in the earlier passage of cultured SK-N-SH-MJD78 cells, however, the later passage of cells showed a significant increase of Hsp27 to almost the same level of the parental cells. Furthermore, immunohistochemical analysis of MJD transgenic mice and post-mortem human brain tissues showed increased expression of Hsp27 compared to normal control brain, suggesting an up-regulation of Hsp27 in the end stage of MJD. However, mutant cells of earlier passages were more susceptible to serum deprivation than mutant cells of later passages, indicating weak tolerance toward stress in cells with reduced Hsp27. While heat shock was used to assess the stress response, cells expressing mutant ataxin-3 displayed normal response upon heat shock stimuli when compared to the parental cells. Taken together, we proposed that during the early disease stage, the reduction of Hsp27 synthesis mitigated the ability of neuron cells to cope with cytotoxicity induced by mutant ataxin-3, triggering the cell death process during the disease progress. In the late stage of disease, after prolonged stressful conditions of polyglutamine cytotoxicity, the increased level of Hsp27 may reflect a dynamic process of the survived cells to unfold and remove mutant ataxin-3. However, this increased Hsp27 still cannot reverse the global dysfunction of cellular proteins due to accumulation of cytotoxic effects.
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PMID:Dynamic expression of Hsp27 in the presence of mutant ataxin-3. 1612 76

Genetic ablation of the fibroblast growth factor (Fgf) 14 gene in mice or a missense mutation in Fgf14 in humans causes ataxia and cognitive deficits. These phenotypes suggest that the neuronally expressed Fgf14 gene is essential for regulating normal neuronal activity. Here, we demonstrate that FGF14 interacts directly with multiple voltage-gated Na(+) (Nav) channel alpha subunits heterologously expressed in non-neuronal cells or natively expressed in a murine neuroblastoma cell line. Functional studies reveal that these interactions result in the potent inhibition of Nav channel currents (I(Na)) and in changes in the voltage dependence of channel activation and inactivation. Deletion of the unique amino terminus of the splice variant of Fgf14, Fgf14-1b, or expression of the splice variant Fgf14-1a modifies the modulatory effects on I(Na), suggesting an important role for the amino terminus domain of FGF14 in the regulation of Na(v) channels. To investigate the function of FGF14 in neurones, we directly expressed Fgf14 in freshly isolated primary rat hippocampal neurones. In these cells, the addition of FGF14-1a-GFP or FGF14-1b-GFP increased I(Na) density and shifted the voltage dependence of channel activation and inactivation. In fully differentiated neurones, FGF14-1a-GFP or FGF14-1b-GFP preferentially colocalized with endogenous Nav channels at the axonal initial segment, a critical region for action potential generation. Together, these findings implicate FGF14 as a unique modulator of Nav channel activity in the CNS and provide a possible mechanism to explain the neurological phenotypes observed in mice and humans with mutations in Fgf14.
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PMID:Fibroblast growth factor 14 is an intracellular modulator of voltage-gated sodium channels. 1616 53

Opsoclonus-myoclonus syndrome is a distinct neurologic disorder characterized by opsoclonic eye movements, multifocal myoclonus, and ataxia, traditionally described as "dancing eyes, dancing feet." A presenting sign in 2% of children with neuroblastoma, it usually heralds a favorable prognosis for the tumor. Although opsoclonus-myoclonus syndrome usually presents at initial diagnosis or relapse, there are reports of delayed presentation, usually a few months after diagnosis. This report describes a patient with ganglioneuroblastoma who developed recurrent symptoms of opsoclonus-myoclonus syndrome 9 years after completing treatment, without evidence of recurrent tumor. Believed to be autoimmune in origin, opsoclonus-myoclonus syndrome frequently responds to immunomodulatory therapies, such as steroids or intravenous immunoglobulin. This patient did not respond adequately to either agent, so plasmapheresis, a less commonly used modality in opsoclonus-myoclonus syndrome, was attempted. His symptoms resolved after he received therapy with a combination of plasmapheresis and steroids over a 1-year period. After being slowly weaned off all therapy, he has been symptom-free now for over 3 years. Armstrong MB, Robertson PL, Castle VP. Delayed, recurrent opsoclonus-myoclonus syndrome responding to plasmapheresis.
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PMID:Delayed, recurrent opsoclonus-myoclonus syndrome responding to plasmapheresis. 1624 25

Telomeres are specialized structures at the ends of chromosomes that consist of tandem repeats of the DNA sequence TTAGGG and several proteins that protect the DNA and regulate the plasticity of the telomeres. The telomere-associated protein TRF2 (telomeric repeat binding factor 2) is critical for the control of telomere structure and function; TRF2 dysfunction results in the exposure of the telomere ends and activation of ATM (ataxia telangiectasin mutated)-mediated DNA damage response. Recent findings suggest that telomere attrition can cause senescence or apoptosis of mitotic cells, but the function of telomeres in differentiated neurons is unknown. Here, we examined the impact of telomere dysfunction via TRF2 inhibition in neurons (primary embryonic hippocampal neurons) and mitotic neural cells (astrocytes and neuroblastoma cells). We demonstrate that telomere dysfunction induced by adenovirus-mediated expression of dominant-negative TRF2 (DN-TRF2) triggers a DNA damage response involving the formation of nuclear foci containing phosphorylated histone H2AX and activated ATM in each cell type. In mitotic neural cells DN-TRF2 induced activation of both p53 and p21 and senescence (as indicated by an up-regulation of beta-galactosidase). In contrast, in neurons DN-TRF2 increased p21, but neither p53 nor beta-galactosidase was induced. In addition, TRF2 inhibition enhanced the morphological, molecular and biophysical differentiation of hippocampal neurons. These findings demonstrate divergent molecular and physiological responses to telomere dysfunction in mitotic neural cells and neurons, indicate a role for TRF2 in regulating neuronal differentiation, and suggest a potential therapeutic application of inhibition of TRF2 function in the treatment of neural tumors.
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PMID:TRF2 dysfunction elicits DNA damage responses associated with senescence in proliferating neural cells and differentiation of neurons. 1653 55

A 2-year-old boy presented with acute cerebellar ataxia without opsoclonus. The ataxia was assumed to be post-viral. After a period of years a neuroblastoma was detected. Treatment with a curative intent was successful and consisted of metaiodobenzylguanidine I 131, chemotherapy, tumour resection, chemotherapy again and follow-up treatment with isotretinoin after irradiation. In the literature, 5 other children have been described with acute cerebellar ataxia without opsoclonus in whom neuroblastoma was detected eventually. The mean age of these children at initial presentation was 26 months. The mean time between initial presentation and diagnosis ofneuroblastoma or ganglioneuroblastoma was 12 months. Urine concentrations of catecholamine metabolites were normal in 5 of the 6 total children; concentrations were elevated in 1 child. The tumour was located paravertebrally in 5 of the 6 children. Ataxia resolved following resection of the neuroblastoma in all patients. Each child with prolonged or recurrent acute cerebellar ataxia should be extensively investigated for the presence of neuroblastoma, even in the absence of opsoclonus.
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PMID:[A boy with acute cerebellar ataxia without opsoclonus caused by neuroblastoma]. 1664

Recent studies have revealed that accumulation of prion protein (PrP) in the cytoplasm results in the production of aggregates that are insoluble in non-ionic detergents and partially resistant to proteinase K. Transgenic mice expressing PrP in the cytoplasm develop severe ataxia with cerebellar degeneration and gliosis, suggesting that cytoplasmic PrP may play a role in the pathogenesis of prion diseases. The mechanism of cytoplasmic PrP neurotoxicity is not known. In this report, we determined the molecular morphology of cytoplasmic PrP aggregates by immunofluorescence and electron microscopy, in neuronal and non-neuronal cells. Transient expression of cytoplasmic PrP produced juxtanuclear aggregates reminiscent of aggresomes in human embryonic kidney 293 cells, human neuroblastoma BE2-M17 cells and mouse neuroblastoma N2a cells. Time course studies revealed that discrete aggregates form first throughout the cytoplasm, and then coalesce to form an aggresome. Aggresomes containing cytoplasmic PrP were 1-5-microm inclusion bodies and were filled with electron-dense particles. Cytoplasmic PrP aggregates induced mitochondrial clustering, reorganization of intermediate filaments, prevented the secretion of wild-type PrP molecules and diverted these molecules to the cytoplasm. Cytoplasmic PrP decreased the viability of neuronal and non-neuronal cells. We conclude that any event leading to accumulation of PrP in the cytoplasm is likely to result in cell death.
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PMID:Molecular morphology and toxicity of cytoplasmic prion protein aggregates in neuronal and non-neuronal cells. 1669 54

Opsoclonus-myoclonus ataxia syndrome is a paraneoplastic syndrome of cerebellar damage associated with neuroblastoma. The authors assessed psychiatric symptoms of opsoclonus-myoclonus ataxia syndrome in 17 children, who were 16 months to 12(1/2) years of age. Psychiatric symptoms examined included disruptive behavior, affective dysregulation, irritability, impulsivity, cognitive impairment, and poor attention.
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PMID:Mood and behavioral dysfunction with opsoclonus-myoclonus ataxia. 1672 Aug 3

Opsoclonus-myoclonus syndrome (OMS) in children is a rare neurological condition with opsoclonus, myoclonus, ataxia and irritability in the first 2 years of life. It can be idiopathic, parainfectious, or paraneoplastic with tumours of the neural crest. Few studies of long-term follow-up after OMS have been published. We investigated the motor, cognitive and behavioural outcome of ten patients (eight girls and two boys) seen between 1987 and 2002. We reviewed the records and reassessed the patients. A ganglioneuroma was found in one patient and a neuroblastoma in another. Tumour resection did not influence the OMS. The age at diagnosis was 10-24 months and the follow-up period 1-17 years (average 6.5 years). The interval between the first signs and symptoms and starting treatment was 2-12 weeks: treatment consisted of different immunosupressants. Remission was achieved within 5 months in seven, and relapses were present in seven of ten. At follow-up, only one child had mild ataxia. IQ testing was performed in nine with scores below 75 in four and above 85 in four. Attention deficit and visuomotor difficulties led to school problems with special needs, also in those three children with normal IQs. Only two children were attending regular schools. Behavioural problems were reported in seven, and speech difficulties were present in five. In conclusion, the long-term outcome in our patients with OMS was dominated by cognitive and behavioural problems and not by ataxia. Compared with previous reports, our patients were treated earlier. Larger studies and uniform treatment protocols are needed to demonstrate whether early and prolonged immunosupressant therapy has a favourable influence on outcome.
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PMID:Long-term outcome of ten children with opsoclonus-myoclonus syndrome. 1708 89

Opsoclonus-myoclonus-ataxia-syndrome (OMS) represents a rare neuroblastoma-associated paraneoplastic syndrome that commonly results in neurologic deficits despite tumor resection and immunosuppressive therapy. We describe the response of five such children to high-dose dexamethasone pulses including two patients in whom previous glucocorticoids, rituximab, and cytostatic drugs were not successful. All patients had MYCN non-amplified tumors that were detected 1 to 7 months after the onset of the OMS or ataxia. This treatment resulted in a good partial response in three and in complete remission in two patients. Our results show that dexamethasone pulses are likely to be useful for both, first-line- and salvage-therapy for OMS-patients.
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PMID:Treatment of neuroblastoma-related opsoclonus-myoclonus-ataxia syndrome with high-dose dexamethasone pulses. 1722 43

Opsoclonus-myoclonus syndrome (OMS) is a rare movement disorder characterized by chaotic eye movements, myoclonus, and ataxia associated with severe irritability. Different treatment modalities including steroids and cyclophosphamide have been tried in the past often with significant side effects and variable success. Here we present 11 children, diagnosed with OMS between 1999 and 2005 and treated with high dose dexamethasone pulses. Main symptoms at presentation were opsoclonus (11/11), ataxia and/or myoclonus (11/11), irritability (10/11) associated with a neuroblastoma in four children. Number of dexamethasone pulses ranged from 6 to 60 pulses. No major side effects were reported. In 6/11 children a complete and sustained remission of OMS symptoms was achieved after 6 to 29 pulses of dexamethasone. Two children from this group have a normal development and no neurological sequelae. Two further children have minor delays in fine- and gross-motor skills. Two children despite a complete recovery of OMS symptoms have persisting developmental problems. 5/11 children still require regular dexamethasone pulses in addition to daily prednisolone (n = 1) or have received cyclophosphamide pulses meanwhile (n = 2). All children continue to have developmental and neurological difficulties. In summary treatment with high dose pulsatile dexamethasone appears to be safe and beneficial in a subgroup of patients with OMS.
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PMID:High dose pulsatile dexamethasone therapy in children with opsoclonus-myoclonus syndrome. 1723 8


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