Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The BE(2)-M17 and BE(2)-C human neuroblastoma cell lines have been shown to synthesize and secrete corticotropin-releasing factor (CRF) following retinoic acid treatment. It has been demonstrated that CRF secretion and intracellular synthesis increases in response to forskolin treatment. In this report, we have further characterized these cells in response to protein kinase C activators, dexamethasone, interleukin-1 alpha, as well as various neurotransmitters and peptides. Nanomolar concentrations of the phorbol ester--phorbol 12 myristate 13--acetate (TPA), increased intracellular CRF content in both cell lines while increasing secretion only in the BE(2)-M17 cell. Nanomolar concentrations of dexamethasone were not able to alter basal levels of secretion and content in either cell type. However, in the BE(2)-M17 cell but not the BE(2)-C cell, the same concentrations of dexamethasone added to 30 microM forskolin augmented levels of CRF secretion and content. Likewise, the same augmented response in CRF secretion and content was seen only in the BE(2)-M17 cell line when nanomolar concentrations of dexamethasone were added to 20 nM TPA. Furthermore, only in the BE(2)-M17 cell line were micromolar levels of the biogenic amine serotonin able to increase levels of CRF secretion and content. No effects on CRF in both cell lines were demonstrable with picomolar levels of interleukin-1 alpha as well as micromolar levels of acetylcholine, norepinephrine, arginine-vasopressin, oxytocin, and angiotensin-II. The potential usefulness of these cells as models of central nervous system or placental CRF-containing neurons is discussed.
 ...
PMID:Regulation of corticotropin-releasing factor secretion and synthesis in the human neuroblastoma clones- BE(2)-M17 and BE(2)-C. 755 Feb 93

Esthesioneuroblastoma or olfactory neuroblastoma, is a rare tumour. It was first described by Berger et al. in 1924. Since then, approximately 250 cases have been reported. These neuroendocrine neoplasms are rarely associated with hormone excess syndromes. We report a case of olfactory neuroblastoma initially manifested with a syndrome of inappropriate secretion of antidiuretic hormone (SIADH) in a 27-year-old man. A literature review is briefly presented.
 ...
PMID:Olfactory neuroblastoma: report of a case associated with inappropriate antidiuretic hormone secretion. 789 75

Olfactory neuroblastoma is an uncommon intranasal neoplasm that has not been previously documented to invade the oral cavity. The tumor's variable clinical manifestations and microscopic features may create a diagnostic dilemma for the clinician. The neoplasm has been identified as a direct cause of ectopic arginine vasopressin production leading to inappropriate antidiuretic hormone secretion. An unusual case of olfactory neuroblastoma invading the oral cavity through the maxillary sinus in a patient with pathologic antidiuretic hormone secretion is reported.
 ...
PMID:Olfactory neuroblastoma invading the oral cavity in a patient with inappropriate antidiuretic hormone secretion. 806 32

Mouse neuroblastoma Neuro-2a cells were examined for the expression of pro-enkephalin mRNA, protein, and Met-enkephalin ([Met]-Enk) peptide. Reverse transcriptase/polymerase chain reaction (RT/PCR) and in situ hybridization demonstrated the presence of pro-enkephalin mRNA in these cells. Immunocytochemistry using an antibody which recognizes pro-enkephalin and high pressure liquid chromatography (HPLC) followed by radioimmunoassay indicated that pro-enkephalin was synthesized in these cells and processed to yield the bioactive pentapeptide, [Met]-Enk. Furthermore, release studies showed that the [Met]-Enk was secreted from these cells with high K+ stimulation. Using double labeling, in situ hybridization combined with immunocytochemistry, we demonstrated that prohormone convertase 2 (PC2) mRNA is colocalized with pro-enkephalin in the same Neuro-2a cells, suggesting that this enzyme may be responsible for processing this precursor. we also showed the presence of vasopressin mRNA and arginine-vasopressin peptide in these cells using in situ hybridization and immunocytochemistry, respectively. Thus, the Neuro-2a cells are a multiple neuropeptide-producing cell line and an excellent model for studying the mechanisms involved in the synthesis, intracellular targeting and processing of endogenous pro-enkephalin and pro-vasopressin, as well as other transfected neuropeptide precursors.
 ...
PMID:The Neuro-2a neuroblastoma cell line expresses [Met]-enkephalin and vasopressin mRNA and peptide. 867 23

Mutations in the arginine vasopressin (AVP) gene cause autosomal dominant familial neurohypophyseal diabetes insipidus (FNDI). The dominant inheritance pattern has been postulated to reflect neuronal toxicity of the mutant proteins, but the mechanism for such cytotoxicity is unknown. In this study, wild-type or several different mutant AVP genes were stably expressed in neuro2A neuroblastoma cells. When cells were treated with valproic acid to induce neuronal differentiation, each of the mutants caused reduced viability. Metabolic labeling revealed diminished intracellular trafficking of mutant AVP precursors and confirmed inefficient secretion of immunoreactive AVP. Immunofluorescence studies demonstrated marked accumulation of mutant AVP precursors within the endoplasmic reticulum. These studies suggest that the cellular toxicity in FNDI may be caused by the intracellular accumulation of mutant precursor proteins.
 ...
PMID:Molecular basis of autosomal dominant neurohypophyseal diabetes insipidus. Cellular toxicity caused by the accumulation of mutant vasopressin precursors within the endoplasmic reticulum. 910 34

We report three cases of neuroblastoma arising within the thymus of elderly patients. All tumors consisted of primitive neuroblasts showing focal gangliocytic differentiation within nests of neuropil. All stained for neuroendocrine markers but were negative for cytokeratins and for the MIC2 gene product. One tumor was associated with the syndrome of inappropriate secretion of antidiuretic hormone, an endocrinopathy we found in three of five case reports of thymic neuroblastoma in adults. Immunohistochemical stains confirmed production of antidiuretic hormone by this tumor. One patient died of progressive disease, one patient is disease free at 18 months, and the other patient died of unrelated causes, a spectrum that reflects the variable clinical behavior others have reported. The possible histogenesis of these purely neural tumors includes malignant transformation of a mediastinal teratoma, aberrantly located sympathetic ganglia, neuroectodermal cells native to the normal thymus, and precursors of thymic epithelial cells that have differentiated along neural lines.
 ...
PMID:Thymic neuroblastoma in adults: report of three cases with special emphasis on its association with the syndrome of inappropriate secretion of antidiuretic hormone. 935 92

Sinonasal teratocarcinosarcoma (SNTC) is a rare, aggressive, histologically heterogeneous neoplasm of the paranasal sinuses and nasopharnyx of adults that is composed of variably benign or malignant neuroepithelial, epithelial, and mesenchymal elements. Occasional cases show intracranial extension and may be operated on by neurosurgeons and encountered by neuropathologists who may not be familiar with the entity. STNCs have not previously been associated with functional hypersecretory status. We report a 59-year-old male who presented with headache and syndrome of inappropriate secretion of antidiuretic hormone (SIADH) and was subsequently found to have a bulky tumor of the frontal and ethmoid sinuses with focal dural invasion. The tumor was predominantly composed of olfactory neuroblastoma areas (90% of tumor) admixed with unusually well-developed craniopharyngioma-like mature squamous epithelium and ghost cells ( 10% of tumor). Scattered neuroblastoma tumor cells showed strong immunoreactivity with antibodies to arginine vasopressin, supporting ectopic hormone secretion by the tumor. While the coexistence of neuroectodermal and oral ectodermal-like differentiation in SNTCs is characteristic, in our case it was developed to an extreme functional and morphologic degree and was unassociated with other mesenchymal or epithelial elements often found in these complex tumors. SNTCs with limited differentiation have prompted controversy in classification.
 ...
PMID:Sinonasal teratocarcinosarcoma ("mixed olfactory neuroblastoma-craniopharyngioma") presenting with syndrome of inappropriate secretion of antidiuretic hormone. 1074 86

Biosynthesis of the vasopressin (VP) prohormone in magnocellular neurones of the hypothalamo-neurohypophysial system comprises endoplasmic reticulum (ER) transit, sorting into the regulated secretory pathway and subsequent processing in the individual proteins VP, neurophysin and a glycoprotein. These processes are severely disrupted in the homozygous diabetes insipidus (di/di) Brattleboro rat, which expresses a mutant VP precursor due to a single nucleotide deletion in the neurophysin region of the VP gene resulting in VP deficiency. Previous studies have shown the presence of additional frameshift mutations in VP transcripts, in solitary magnocellular neurones of the di/di rat due to a GA dinucleotide deletion resulting in two different mutant VP precursors with partly restored reading frame. Frameshifted VP precursors are also expressed in several magnocellular neurones in wild-type rats. In this study, we determined if the +1 frameshifted precursors from di/di and wild-type rats can lead to biosynthesis of the hormone VP. Therefore, eukaryotic expression plasmids containing the frameshifted VP cDNAs were transiently expressed in peptidergic tumour cell lines, and cells were analysed by reversed phase high-performance liquid chromatography and specific radioimmunoassays, and by immunofluoresence. Neuro2A neuroblastoma cells expressing the +1 frameshifted precursors of di/di rats retained products in the cell body. Only precursor or insignificant quantities of neurophysin-immunoreactive products were detected. In contrast, in AtT20 cells, frameshifted VP precursors were at least partly processed to yield the VP peptide, indicating that they have access to the regulated secretory pathway. Comparison between the two cell lines showed a very slow ER transit of the wild-type prohormone combined with inefficient processing in Neuro2A cells. The results show that mutant precursors can reach the regulated secretory pathway if ER transport is sufficiently rapid as in the case of AtT20 cells. This suggests that the di/di rat may regain the capacity to biosynthesize authentic VP through these +1 frameshifted precursors in magnocellular neurones.
 ...
PMID:Processing of frameshifted vasopressin precursors. 1084 14

Molecular misreading is a novel process that causes mutations in neuronal transcripts. It is defined as the inaccurate conversion of genomic information from DNA into nonsense transcripts and the subsequent translation into mutant proteins. As a result of dinucleotide deletions (delta GA, delta GU, delta CU) in and around GAGAG motifs in mRNA the reading frame shifts to the +1 frame, and subsequently the so-called +1 proteins are synthetized. +1 Proteins have a wild-type NH2 terminus and from the site of the dinucleotide deletion onwards an aberrant, nonfunctional COOH terminus. Molecular misreading was found in the rat vasopressin gene associated with diabetes insipidus and in the human genes linked to Alzheimer's disease (AD), that is, beta-amyloid precursor protein (beta APP) and ubiquitin-B (UBB). Moreover, beta APP+1 and UBB+1 proteins accumulate in the neuropathological hallmarks of AD. Inasmuch as these +1 proteins were also found in elderly, nondemented control patients, but not in younger ones (< 72 years), molecular misreading may act as a factor that becomes manifest in aged people. A hotspot for dinucleotide deletions is GAGAG motifs. Because statistically an average of 2.1 GAGAG motifs per gene can be expected, other genes expressed in other tissues may undergo molecular misreading as well. Indeed, we recently detected +1 proteins in proliferating cells present in tissues such as the liver, epididymis, parotid gland, and neuroblastoma cell lines. Therefore, molecular misreading can be regarded as a general biological source of transcript errors that may be involved in cellular derangements in numerous age-related pathologic conditions apart from Alzheimer's disease.
 ...
PMID:Molecular misreading. A new type of transcript mutation in gerontology. 1091 66

Dinucleotide deletions (e.g. DeltaGA, DeltaGU) are created by molecular misreading in or adjacent to GAGAG motifs of neuronal mRNAs. As a result, the reading frame shifts to the +1 frame, and so-called "+1 proteins" are subsequently synthesized. +1 Proteins have a wild-type N-terminus, but an aberrant C-terminus downstream from the site of the dinucleotide deletion. Molecular misreading was discovered in the rat vasopressin gene associated with diabetes insipidus and subsequently in human genes linked to Alzheimer's disease (AD), e.g. beta amyloid precursor protein (betaAPP) and ubiquitin-B (UBB). Furthermore, betaAPP(+1) and UBB(+1) proteins accumulate in the neuropathological hallmarks (i.e. in the tangles, neuritic plaques, and neuropil threads) of AD. As these +1 proteins were also found in elderly nondemented controls, but not in younger ones (<51 years), molecular misreading in nondividing cells might act as a factor that only becomes manifest at an advanced age. Frameshift mutations (UBB(+1)) and pretangle staining (Alz-50 and MC1) seem to occur independently of each other during early stages of AD. We recently detected +1 proteins, not only in proliferating cells present in non-neuronal tissues such as the liver and epididymis, but also in neuroblastoma cell lines. These observations suggest that molecular misreading is a general source of transcript errors that are involved in cellular derangements in various age-related pathologies.
 ...
PMID:Molecular misreading: a new type of transcript mutation expressed during aging. 1112 39


<< Previous 1 2 3 4 Next >>