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)

Fucosyl residues in the alpha 1----3 linkage to N-acetylglucosamine (Fuc alpha 1----3GlcNAc) on oligosaccharides of glycoproteins and glycolipids have been detected in certain human tumors and are developmentally expressed (reviewed in Foster, C. S., and Glick, M. C. (1988) Adv. Neuroblastoma Res. 2, 421-432). In order to understand control mechanisms for the biosynthesis of these fucosylated glycoconjugates, GDP-L-Fuc-N-acetyl-beta-D-glucosaminide alpha 1----3fucosyltransferase was purified from human neuroblastoma cells, CHP 134, utilizing either the immobilized oligosaccharide or disaccharide substrates. The enzyme, extracted from CHP 134 cells, was purified by DEAE- and SP-Sephadex chromatography and then by either immobilized substrate. alpha 1----3Fucosyltransferase was obtained in approximately 10% yield and was purified 45,000-fold from the cell extract. The kinetic properties of the enzyme showed an apparent KGDP-Fuc 43 microM, KGal beta 1----4GlcNAc 0.4 mM, KGal beta 1----4Glc 8.1 mM, and KFuc alpha 1----2Gal beta 1----4Glc 1.0 mM. Polyacrylamide gel electrophoresis of the affinity-purified enzyme showed two proteins which migrated, Mr = 45,000-40,000. The enzyme differed in substrate specificity, pH optimum, response to N-ethylmaleimide and ion requirements from the enzymes purified from human milk or serum. The inability of alpha 1----3fucosyltransferase to transfer to substrates containing NeuAc alpha 2----3 or alpha 2----6Gal is in contrast to the reports for the enzyme in other human tumors. This substrate specificity correlates with the oligosaccharide residues thus far defined on glycoproteins of CHP 134 cells since NeuAc and Fuc alpha 1----3GlcNAc have yet to be detected on the same oligosaccharide antenna. However, the enzyme transfers to Fuc alpha 1----2Gal beta 1----4GlcNAc/Glc with higher activity than the unfucosylated disaccharides, although neither alpha 1----2fucosyltransferase nor Fuc alpha 1----2 residues have been detected in CHP 134 cells. The different substrate specificities of alpha 1----3fucosyltransferase isolated from human tumors and normal sources leads to the suggestion that a family of alpha 1----3fucosyltransferases may exist and that they may be differentially expressed in human tumors.
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PMID:Purification and characterization of GDP-L-Fuc-N-acetyl-beta-D-glucosaminide alpha 1----3fucosyltransferase from human neuroblastoma cells. Unusual substrate specificities of the tumor enzyme. 199 16

Neuroblastoma may arise from the blockage of differentiation of neuroblast along the neuronal pathway. In previous studies, we were able to induce differentiation of certain neuroblastoma cell lines with NGF. In order to study the gene regulation during differentiation, we hybridized several cDNA probes with RNA extracted from different cell lines before and after NGF treatment, and found that c-myc oncogene was down-regulated in NGF-induced differentiated cells in comparison with the control samples. The time course of c-myc down-regulation was concordant with the appearance of morphological changes of differentiation. No significant change was found in the expression of other oncogenes like K-ras and N-ras in the neuroblastoma cell lines before and after NGF treatment. The results indicate that down-regulation of c-myc oncogene may be one of the important events during NGF-induced differentiation and over expression of c-myc oncogene may, at least partly, be responsible for the development of neuroblastoma.
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PMID:[Gene regulation during NGF--induced differentiation of neuroblastoma cells]. 206 83

In 1971, the Japanese Society of Pediatric Surgeons' Committee on Malignancies proposed new criteria for neuroblastoma staging. It was fundamentally, based on the system of Evans et al. described in 1971. The main difference was the separation of stage IV disease into stages IV-A, with metastases to bone, orbita, distant lymph nodes and viscera other than liver, IV-B, the primary tumor extending over the midline and with metastases to bone marrow, liver and skin, and IV-S, which was the same as that of Evans et al. The new criteria did not include the resectability of the primary tumor, assessment of regional lymph node involvement or any other disease assessment resulting from therapeutic intervention. For the purpose of international usage, the Japanese system has been newly formulated and proposed as the Japanese Tumor Node Metastasis (TNM) Postsurgical Histopathological Classification for Neuroblastoma. In the present report, 495 neuroblastomas, registered between 1970 and 1985, were analyzed retrospectively according to the International Union Against Cancer (UICC) TNM classification and the proposed Japanese TNM system. The analyses suggested that the Japanese system reflected both the extent of tumor invasion and its biological neuroblastoma characteristics better than the UICC TNM classification based on statistical analysis.
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PMID:Proposal and assessment of Japanese tumor node metastasis postsurgical histopathological staging system for neuroblastoma based on an analysis of 495 cases. 206 17

Aldose reductase activity is increased in neuroblastoma cells grown in media containing 30 mM fructose and/or 30 mM glucose. Neuroblastoma cells cultured in media supplemented with increased concentrations of glucose and fructose amass greater amounts of sorbitol than do cells exposed to media containing only high glucose concentrations. The increase in sorbitol content is dependent on the fructose and glucose concentration in the media. The increase in sorbitol content caused by exposing neuroblastoma cells to media containing 30 mM glucose/30 mM fructose is due to a protein synthesis sensitive mechanism and not to an alteration in the redox state. The addition of sorbinil to media containing 30 mM glucose blocks the increase in sorbitol content. In contrast, sorbinil treatment of media containing 30 mM glucose/30 mM fructose does not totally block the increase in sorbitol levels. myo-Inositol accumulation and incorporation into inositol phospholipids and intracellular myo-inositol content are decreased in cells chronically exposed to media containing 30 mM glucose or 30 mM glucose/30 mM fructose compared to cells cultured in unsupplemented media or media containing 30 mM fructose. However, maximal depletion of myo-inositol accumulation and intracellular content occurs earlier in cells exposed to media containing 30 mM glucose/30 mM fructose than in cells exposed to media supplemented with 30 mM glucose. Sorbinil treatment of media containing 30 mM glucose/30 mM fructose maintains cellular myo-inositol accumulation and incorporation into phospholipids at near normal levels. myo-Inositol content in neuroblastoma cells chronically exposed to media containing 30 mM glucose or 30 mM glucose/30 mM fructose recovers within 72 h when the cells are transferred to unsupplemented media or media containing 30 mM fructose. In contrast, the sorbitol content of cells previously exposed to media containing 30 mM glucose or 30 mM glucose/30 mM fructose then transferred into media containing 30 mM fructose remains elevated compared to the sorbitol content of cells transferred into unsupplemented media. These data suggest that fructose may be activating or increasing sorbinil-resistant aldose reductase activity as well as partially blocking sorbitol dehydrogenase activity. The presence of increased concentrations of fructose in combination with increased glucose levels may enhance alterations in cell metabolism and properties due to increased sorbitol levels.
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PMID:Effect of fructose supplementation on sorbitol accumulation and myo-inositol metabolism in cultured neuroblastoma cells exposed to increased glucose concentrations. 211 46

1. Neuroblastoma (NB) is an unusual neuroectodermal tumor showing a high degree of spontaneous regression. NB cells can be induced to differentiate in vitro by various agents. Cell differentiation results in morphological changes characteristic of the mature neuronal phenotype, including outgrowth of neurite-like structures with several interconnections. 2. Recent experiments indicate that morphological differentiation of NB cells is associated with changes in expression of N-myc, c-myc, and c-myb oncogenes and synthesis of neurofilament proteins. However, little is known about the transcription of neurofilament genes during differentiation. 3. We have analyzed the expression of both the N-myc oncogene and mid-size neurofilament (NF) genes in the LAN-1 human NB cell line, cultured in the presence of retinoic acid (RA). Continuous treatment with RA induced morphological differentiation within 5-6 days. The transcription of N-myc was down-modulated within 24 hr of the initial exposure to RA. The mid-size NF mRNA was increased at this time. The expression of N-myc was not modified in serum-deprived LAN-1 cells, indicating that N-myc transcription is unaffected by the arrest of the cells in the G1 phase. 4. We conclude that new synthesis of mid-size NF mRNA and a decrease in N-myc transcription precede de novo formation of neurite-like processes and morphological cell differentiation of neuroblastoma cells.
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PMID:Different regulation of mid-size neurofilament and N-myc mRNA expression during neuroblastoma cell differentiation induced by retinoic acid. 212 47

Neuroblastoma cells maintained in serum-free medium exhibit a significant induction of MAP-1a and Tau proteins, but not MAP-2; the time course of these inductions is highly correlated with an increase in microtubule mass which parallels neurite growth. Bovine brain gangliosides (BBG) enhance the neurite outgrowth response of these cells. We report here that one effect of gangliosides is the selective and dramatic induction of MAP-2 expression. Our results also indicate a strong parallelism between this induction and the increase in microtubule mass which accompanies the appearance of more numerous, longer, and highly branched neurites. These observations suggest that MAP-2 induction in neuroblastoma cells may lead to a further differentiation of neurites equivalent to that observed in mature brain neurons. Finally, our results indicate that gangliosides per se are not neuritogenic factors but rather substances capable of enhancing cell-derived influences which affect the neurite outgrowth response of neuroblastoma cells and the type of MAP that they express.
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PMID:Ganglioside-enhanced neurite growth: evidence for a selective induction of high-molecular-weight MAP-2. 215 74

Neuroblastoma cells (N1E-115) were used as models of transient (T) and long-lasting (L) Ca++ channels. The whole cell version of the patch clamp technique was used to measure inward Ca++ currents, and the fluorescent indicator, Fura-2, was used to measure changes in intracellular Ca++. Cells were cultured and selected during recording so that predominantly T or L channel currents were measured. T channel currents did not respond to dihydropyridine or parathyroid hormone, whereas L channel currents did. BAY-K-8644 increased and nifedipine decreased L channel currents. After a 15 mM KCl challenge, cells with predominantly T channels responded with a transient change in intracellular Ca++, while cells with predominantly L channels showed a sustained response. PTH inhibited the increase in intracellular Ca++ in cells with L channels, but not in those with T channels. PTH may be an example of an endogenous calcium channel blocker, at least in neuroblastoma cells.
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PMID:Control of calcium channels in neuroblastoma cells (N1E-115). 217 70

Neuroblastoma is one of the most frequent tumors in childhood. Suprarenal area is its main abdominal location, appearing in lesser proportion in paravertebral ganglionar chains. Its prediction depends principally on the age of the patient and the pathological stage. US are the best method for its diagnosis. Its most frequent appearance is as an hyperechogenic heterogeneous mass with calcifications inside. In evaluation tumoral extension, other complementary methods such as CT and MRI should be used.
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PMID:[Ultrasonic diagnosis of neuroblastoma]. 219 42

Increase of the dosage of cellular oncogens by DNA amplifications is a frequent genetic alteration of cancer cells. The presence of amplified cellular oncogenes is usually signalled by conspicuous chromosomal abnormalities, "double minutes" (DMs) or "homogeneously staining regions (HSRs). Some human cancers carry a specific amplified oncogene at high incidence. Particularly in neuroblastomas and in breast cancers the amplification of cellular oncogenes has been found associated with aggressively growing cancers and is an indicator for poor prognosis. Neuroblastoma, a malignant tumor of the sympathetic nervous system of children, frequently carries amplification of the oncogene MYCN. The amplification of MYCN is of predictive value for identifying high risk neuroblastoma patients that require specific therapeutic regimen and is generally viewed as the first oncogene alteration that turned out to be of practical clinical significance.
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PMID:[Amplification of N-myc in neuroblastoma: paradigm for clinical use of an oncogene alteration]. 220 36

Growth curves of two human tumour cell lines grown as multicellular tumour spheroid (MTS) were used to obtain survival estimates by back-extrapolation after split and single dose irradiation. Neuroblastoma (NB-100) and squamous cell carcinoma (HN-1) single cells from monolayer culture were assessed for repair of sublethal and potentially lethal damage. The extent of repair was calculated on an iso-effect basis. When grown as spheroids squamous cell carcinoma cells showed a higher capacity to repair sublethal damage than neuroblastoma cells. Repair of potentially lethal damage did not contribute to this higher capacity of HN-1 cells, since this cell line was found to be deficient for this type of repair. Using the recovery ratio to estimate the beta-component of the survival curves, it was found that differences in repair capacity were determined by the alpha-component of the equation. Our results show the feasibility of back-extrapolating multicellular tumour spheroid growth curves to obtain survival estimates that can be applied to establish sublethal damage repair capacity.
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PMID:Repair of radiation induced damage in two human tumour cell lines grown as spheroids and monolayers. 226 13


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