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)

Ethylcholine mustard aziridinium ion (AF64A, MEChMAz) has been proposed as a cholinergic neuron-specific neurotoxin. We report that in further studies on its mechanism of action incubation of the cholinergic neuroblastoma X glioma cell line, NG-108-15, with 100 microM AF64A resulted in a rapid decrease in cellular choline acetyltransferase (ChAT) activity which preceded cytotoxicity. Thus, a 60-85% decrease in ChAT activity was measured within 5 h of AF64A exposure, whereas cell lysis (measured as the release of the cytosolic enzyme lactate dehydrogenase into the medium) did not become apparent until 18 h of AF64A exposure. This led us to examine the effects of AF64A on partially purified ChAT. We report a concentration- and time-dependent inhibition of partially purified ChAT by AF64A that could not be reversed by dialysis but could be prevented by coincubation of the enzyme and AF64A with choline but not with acetyl-coenzyme A. We present kinetic evidence that choline and AF64A compete for the same site on the enzyme. In addition, thiosulfate, which inactivates the aziridinium ion, eliminated AF64A's capacity to inhibit the enzyme. AF64A also irreversibly inhibited partially purified choline kinase and acetylcholinesterase but not lactate dehydrogenase, alcohol dehydrogenase, carboxypeptidase A, or chymotrypsinogen, enzymes that do not use choline as a substrate or product. Thus, the data suggest that AF64A acts as an irreversible active site directed inhibitor of ChAT and possibly other enzymes recognizing choline.
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PMID:AF64A: an active site directed irreversible inhibitor of choline acetyltransferase. 383 98

The authors reviewed the case records of 1419 children with acute leukemia and other types of malignant disease involving the bone marrow to define the clinical and laboratory features associated with marrow necrosis as well as the prognostic significance of this complication. Only seven patients were found to have this abnormality: four with newly diagnosed acute lymphoblastic leukemia (ALL), one with relapsed ALL, and two with disseminated neuroblastoma. All patients presented with severe bone pain, bone tenderness, and fever. Levels of serum lactic dehydrogenase were uniformly increased, being especially high in patients with ALL. There was no evidence of severe infection or disseminated intravascular coagulation, complications that have been causally related to marrow necrosis. Four of the five children with ALL remain in complete remission for 10+ to 48+ months. Both patients with neuroblastoma are off therapy, in remission, for 9+ to 15+ months. In contrast to earlier reports, bone marrow necrosis does not appear to confer a poor prognosis in children with malignancy.
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PMID:Bone marrow necrosis in children with malignant disease. 386 Dec 29

Serum and tumor tissue of a patient with neuroblastoma contained an abnormal isoenzyme of lactate dehydrogenase (LDH; EC 1.1.1.27), which, on agarose gel electrophoresis, migrated between LDH-2 and LDH-3 with a mobility the same as that of the extra LDH isoenzyme found in normal human erythrocytes. On surgical removal of the tumor, the high total LDH activity (775 U/L) in the serum of the patient rapidly decreased to normal (70-220 U/L), and the abnormal LDH isoenzyme was no longer detected. The total LDH activity of the abnormal LDH isoenzyme per gram of hemoglobin in the tumor tissue was 26 times that of erythrocytes, suggesting that the abnormal isoenzyme originated mainly from the tumor cells themselves rather than the erythrocytes contained in the tumor tissue. This first report on the appearance of the abnormal LDH isoenzyme in a patient with neuroblastoma suggests that this abnormal LDH isoenzyme may have some significance as a marker enzyme for neurogenic tumors.
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PMID:Abnormal lactate dehydrogenase isoenzyme in serum and tumor tissue of a patient with neuroblastoma. 396 74

Mouse neuroblastoma tumors have only the fifth isozyme band (A(4)) of lactate dehydrogenase, whereas this band is missing in the brain which contained four other bands of lactate dehydrogenase. The alpha-esterase isozyme patterns of tumors, kidney, and brain are similar except that there is an additional slowest-moving form of esterase in all tumor tissues. The malate dehydrogenase pattern is not altered in any of the tissues.
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PMID:Esterase, malate, and lactate dehydrogenases activity in murine neuroblastoma. 471 10

The activity of the neutral, Mg2+-stimulated sphingomyelinase of cultured neuroblastoma cells (N1E-115) is enriched in the plasma membrane fraction and is reduced following treatment of intact or broken cells with trypsin, alpha-chymotrypsin, papain, and protease. Two protease-sensitive enzymes of the cell interior (lactate dehydrogenase and NADPH-cytochrome c reductase) are not affected by protease treatment of intact cells. These results indicate that the neutral, Mg2+-stimulated sphingomyelinase is oriented externally on the plasma membrane of the cultured neuroblastoma cell.
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PMID:Evidence that neutral sphingomyelinase of cultured murine neuroblastoma cells is oriented externally on the plasma membrane. 609 59

The specific activity of lactate dehydrogenase (LDH; EC 1.1.1.27) is induced two-fold by l-norepinephrine (NE) in C6TK- rat glioma cells, but not in NA mouse neuroblastoma cells or various other nonglial cells. Previous reports have shown that the induction is mediated by cyclic AMP (cAMP) and possibly protein phosphorylation, and that it requires RNA and protein synthesis. To study the block to LDH induction in nonglial cells, we hybridized C6TK- cells with NA cells and isolated a hybrid clone in which LDH is inducible by NE. Mouse and rat LDH from hybrid cells were separated by electrophoresis and quantitated by two independent methods, and it was found that mouse and rat LDH were induced equally when cells were exposed to NE. The results suggest that inducibility of LDH is not determined by a cis-acting control at the gene level, but rather by the presence or absence of an earlier component in the cAMP-mediated induction system, and that the induction system acts indiscriminately on all active LDH gene copies in the cell.
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PMID:Induction of both rat and mouse lactate dehydrogenase in hybrids between inducible rat glioma and uninducible mouse neuroblastoma cells. 625 3

Dibutyryl cyclic AMP and butyrate inhibited growth of S-20 (cholinergic) and NIE-115 (adrenergic) neuroblastoma clones. Both these drugs resulted in a parallel increase of choline acetyltransferase and ATP-citrate lyase activities in S-20 neuroblastoma cells. On the other hand, the increase in tyrosine hydroxylase activity in NIE-115 caused by these drugs was not accompanied by a significant change in ATP-citrate lyase activity. Both dibutyryl cyclic AMP and butyrate caused a decrease in fatty acid synthetase activity in both cell lines. The activities of pyruvate dehydrogenase, citrate synthase, choline acetyltransferase, and lactate dehydrogenase in both S-20 and NIE-115 cells were not significantly influenced by the drugs. ATP-citrate lyases from S-20 and NIE-115 had similar kinetic and immunological properties, and their subunits had the same molecular weight as the rat liver enzyme. These data indicate that the differential regulation of ATP-citrate lyase activity in cholinergic and adrenergic cells does not result from the existence of different molecular forms of the enzyme in these cell lines. They also provide further evidence to support the hypothesis that ATP-citrate lyase activity increases during maturation of normal cholinergic neurons and decreases in noncholinergic cells of the brain.
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PMID:The enzymes of acetyl-CoA metabolism in differentiating cholinergic (s-20) and noncholinergic (NIE-115) neuroblastoma cells. 630 53

Although infants (age less than 1 year) with neuroblastoma have a favorable overall prognosis, metastatic disease is associated with poorer treatment outcome. To assess the role of surgery in these patients, the authors reviewed survival data for 151 infants treated for neuroblastoma, focusing on patient and tumor characteristics, biological markers, and surgical management among the 99 patients with metastatic disease. Patients were divided into early (1961 to 1978) and contemporary (1979 to 1993) treatment eras. Potential prognostic factors were statistically tested to determine their significance in affecting survival. Five-year survival by Pediatric Oncology Group stage was: A, 100% (+/- 0%); B, 94% (+/- 6%); DS, 77% (+/- 9%); C, 73% (+/- 9%); and D, 61% (+/- 8%). Survival for infants with metastatic disease (stages C, D, and DS) was affected significantly by treatment era (P = .0001). Analyses restricted to patients treated during the contemporary era showed prognostic significance for DNA index (P = .02), N-myc copy number (P = .007), serum lactate dehydrogenase level (P = .001), and extent of resection (P = .01). A > or = 95% resection of the primary tumor was found to be associated with improved survival. Significantly more surgical complications were associated with resections performed at the time of diagnosis (P = .007), and delaying surgery until after several courses of chemotherapy did not decrease survival. In conclusion, multiple factors affect the outcome of treatment for infants with metastatic neuroblastoma, and whenever feasible, a > or = 95% resection of the primary tumor should be performed in this patient subgroup.
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PMID:Infants with metastatic neuroblastoma have improved survival with resection of the primary tumor. 747 48

It has been shown that nitric oxide (NO) regulates NO synthase (NOS) activity through negative feedback in cytosolic enzyme preparations in various cell types. We compared the effects of the NO-generating compounds S-nitroso-N-acetylpenicillamine (SNAP), 3-morpholinosydnonimine (SIN-1), and sodium nitroprusside (SNP) on NOS activity in intact neuroblastoma N1E-115 cells and in the cytosol obtained from the same cells. Enzyme activity was measured by the conversion of L-[3H]arginine into L-[3H]citrulline. At concentrations that elicit almost complete inhibition of NOS activity in cytosolic enzyme preparations of these cells, SIN-1 and SNP did not cause significant attenuation of enzyme activity measured at 45 min in intact cells. It is surprising that SIN-1 and SNP markedly stimulated L-[3H]citrulline formation in a time- and concentration-dependent manner when cells were incubated with the compounds for > 1.5 h. Neither inhibitory nor stimulatory effects of SNAP on NOS were observed in intact N1E-115 cells. This is in contrast to the inhibitory effects of SNAP in cytosolic preparations of the enzyme. The increased NOS activity by SIN-1 or SNP in intact cells was dependent on the presence of extracellular Ca2+, suggesting that it might be due to increased Ca2+ influx. On the other hand, measurements of the activity of lactate dehydrogenase showed that there was no generalized increase in cell permeability in response to SIN-1 or SNP. There was no agreement in the rank order of potencies of these compounds in activating guanylate cyclase and in affecting NOS activity, both in broken-cell preparations and in intact cells.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Anomalous increase in nitric oxide synthase activity by certain nitric oxide-generating compounds in intact neuronal cells. 754 Jun 59

A review of stage IV-S neuroblastoma is provided. The possible uses of prognostic features to guide treatment options in this group of infants with neuroblastoma are suggested. The biologic basis for the spontaneous regression of widespread tumor involvement in some infants with stage IV-S neuroblastoma is discussed. The reasons that some infants with IV-S disease progress to a fatal outcome, while most undergo maturation or involution and eventual long term cure are suggested. The influence of such factors as age at diagnosis, clinical staging, and tumor biology on eventual outcome are covered. Biological variables and markers discussed include: genetic (cytogenetics (1p deletions), nuclear genomic content), molecular biologic (N-myc oncogene amplification, mdr-1, ras, and trk, gene expression), immunological (major histocompatibility antigen density, cellular and humoral immunity), and biochemical (creatine kinase isoenzyme profile, neuron specific enolase, ferritin, chromatograffin, lactic acid dehydrogenase and catecholamine levels).
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PMID:Neuroblastoma stage IV-S. 763 37


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