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)

Endogenous expression of human membrane type ganglioside sialidase (Neu3) was examined in various cell lines including NB-1, U87MG, SK-MEL-2, SK-N-MC, HepG2, Hep3B, Jurkat, HL-60, K562, ECV304, Hela and MCF-7. Expression was detected in the neuroblastoma cell lines NB-1 and SK-N-MC, and also in erythroleukemia K562 cells, but not in any other cells. We isolated a Neu3 cDNA from K562 cells and expressed a His-tagged derivative in a bacterial expression system. The purified recombinant product of approximately 48 kDa had sialidase activity toward 4-methyl-umbelliferyl-alpha-D-N-acetylneuraminic acid (4MU-NeuAc). The optimal pH of the purified Neu3 protein for GD3 ganglioside was 4.5. The enzyme also efficiently hydrolyzed GD3, GD1a, GD1b and GM3 whereas sialyllactose, 4MU-NeuAc, GM1 and GM2 were poor substrates, and it had no activity against sialylated glycoproteins such as fetuin, transferrin and orosomucoid. We conclude that the sialidase activity of Neu3 is specific for gangliosides.
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PMID:Molecular characterization of membrane type and ganglioside-specific sialidase (Neu3) expressed in E. coli. 1517 41

Here we present a basic concept and several examples of methods of analysis for chemicals that disrupt cellular signaling pathways, in view of risk assessment for potential endocrine disrupting chemicals (EDCs). The key cellular signaling pathways include 1) ER/coactivator interaction, 2) AR translocation into the nucleus, 3) ER/NO/sGC/cGMP, 4) ER/Akt, 5) ER/Src, 6)ER/Src/Grb2, and 7) ER/Ca2+/CaM/CaMK pathways. These were visualized in relevant live cells using newly developed fluorescent and bioluminescent probes. Changes in cellular signals were thereby observed in nongenomic pathways of steroid hormones upon treatment of the target cells with steroid hormones and related chemicals. This method of analysis appears to be a rational approach to high-throughput prescreening (HTPS) of biohazardous chemicals, EDCs, in particular. Also described was the screening of gene expression by serial analysis of gene expression and gene chips upon applying EDCs to breast cancer cells, mouse livers, and human neuroblastoma NB-1 cells.
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PMID:Methods of analysis for chemicals that disrupt cellular signaling pathways: risk assessment for potential endocrine disruptors. 1579 60

Both tetrodotoxin-sensitive (TTX-S) and TTX-resistant (TTX-R) voltage-dependent Na+ channels are expressed in the human neuroblastoma cell line NB-1, but a gene encoding the TTX-R Na+ channel has not been identified. In this study, we have cloned cDNA encoding the alpha subunit of the TTX-R Na+ channel in NB-1 cells and designated it hNbR1. The longest open reading frame of hNbR1 (accession no. AB158469) encodes 2016 amino acid residues. Sequence analysis has indicated that hNbR1 is highly homologous with human cardiac Nav1.5/SCN5A with > 99% amino acid identity. The presence of a cysteine residue (Cys373) in the pore-loop region of domain I is consistent with the supposition that hNbR1 is resistant to TTX. Analysis of the genomic sequence of SCN5A revealed a new exon encoding S3 and S4 of domain I (exon 6A). In addition, an alternative splicing variant, lacking exon 18, that encodes 54 amino acids in the intracellular loop between domains II and III was found (hNbR1-2; accession no. AB158470). Na+ currents in human embryonic kidney cells (HEK293) transfected with hNbR1 or hNbR1-2 showed electrophysiological properties similar to those for TTX-R I(Na) in NB-1 cells. The IC50 for the TTX block was approximately 8 microM in both variants. These results suggest that SCN5A has a newly identified exon for alternative splicing and is more widely expressed than previously thought.
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PMID:Tetrodotoxin-resistant Na+ channels in human neuroblastoma cells are encoded by new variants of Nav1.5/SCN5A. 1611 3

Thrombin, a serine protease that plays a pivotal role in blood coagulation, wound healing, and angiogenesis, has also been implicated in the mitogenesis of various cell types. Previously, we showed that thrombin and the thrombin receptor agonist peptide (TRAP-14; SFLLRNPNDKYEPF) for protease-activated receptor 1 (PAR1) induce vascular endothelial growth factor (VEGF) secretion in PC-12 cells. In this study, we show that thrombin and TRAP-14 also stimulate VEGF secretion in the human NB-1 neuroblastoma cells. In these cells, we further show that thrombin-induced VEGF secretion was blocked by cycloheximide and actinomycin D, indicating that de novo protein synthesis is essential for this process. Reduced thrombin-induced VEGF secretion upon treatment with LY294002, calphostin C, or BAPTA, further suggests that the process is dependent on phosphatidyl-inositol-3-kinase, protein kinase C, and calcium. However, the complete loss of thrombin-induced VEGF production upon treatment with argatroban, a derivative of arginine and a potent anticoagulant/antithrombin agent, supports the notion that argatroban serves as a useful therapeutic tool for thrombin-associated pathologic conditions. Here, it appears that argatroban may be effective in controlling disorders linked to thrombin-induced VEGF production in neuronal cells.
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PMID:Inhibition of thrombin-induced vascular endothelial growth factor production in human neuroblastoma (NB-1) cells by argatroban. 1629 85

The aim of this study was to evaluate the cytotoxicity of cubic boron nitride (cBN), a component of surgical cutting tools. The small quantities of cBN that typically remain on implants as a result of the manufacturing process may act as abrasives, injuring tissues surrounding the implant. To determine how cBN affects cells, we treated human neuroblastoma cells (NB-1) and human articular chondrocytes (nHAC-kn) with different concentrations of cBN powder and assessed cell growth and cell survival using the methyl-thiazol-tetrazolium (MTT) assay and a fluorescence probe assay. We also assessed the effects of tungsten carbide (WC) and cobalt (Co), two common components of joint implants, on cell growth and cell survival. Both cBN and WC moderately inhibited NB-1 and nHAC-kn cell growth. However, cBN and WC did not affect cell survival, even at high concentrations (40 microg/ml). By contrast, Co affected cell survival, inducing cell death in both cell types at increasing concentrations. These results suggest that cBN may be less toxic than WC alloys containing Co.
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PMID:Cytotoxic evaluation of cubic boron nitride in human origin cultured cells. 1689 Mar 96

Recent evidence suggests an association between up-regulation of beta-catenin/Wnt signaling pathway and neuronal differentiation of neuroblastoma. We overexpressed beta-catenin into a human neuroblastoma cell line NB-1 and observed its effect on cellular morphology, growth potential and alteration in a known differentiation related gene, trkA. Expression plasmids containing wild-type and mutated forms of beta-catenin gene were transfected into NB-1 cells, using liposome-based transfection method. The mutated forms were a deletion of three nucleotides of codon 45 and a large deletion involving the whole exon 3. In the transient transfection model, cell viability assay demonstrated significant negative effect of mutated beta-catenin transfection, but not wild-type, on the cell proliferation. To investigate impacts of beta-catenin overexpression in detail, a stable transfection model was established. Clones with comparable expression of beta-catenin at the mRNA level were selected. Only the selected clones with mutated form of beta-catenin exhibited neurite extension pattern and stunned cell proliferation, in association with higher accumulation of total cellular beta-catenin protein as evidenced by Western blot and immunocytochemistry. Cell cycle progression demonstrated significantly higher G0-G1 fraction in each stable cell clone with beta-catenin expression plasmid. In addition, retarded G1/S transition was observed exclusively in the cell clones with mutated form. Concomitantly with overexpressed beta-catenin, up-regulations of trkA and Ha-ras were also identified. Our study suggests a potential availability of beta-catenin/Wnt signaling pathway as a target of molecular manipulation for treatment of high-risk neuroblastoma and a potential association between the pathway and the trkA/neurotrophin cascades.
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PMID:Artificially accumulated beta-catenin inhibits proliferation and induces neurite extension of neuroblastoma cell line NB-1 via up-regulation of trkA. 1708 37

The aim of the present study was to determine whether phenoxazines such as 2-amino-4,4-alpha-dihydro-4alpha-phenoxazine-3-one (Phx-1) and 2-aminophenoxazine-3-one (Phx-3) may suppress the proliferation of human neuroblastoma cell line, NB-1 that is refractory to chemotherapeutic agents, inducing apoptosis through the activation of caspase pathway or not. Phx-1 and Phx-3 suppressed the proliferation of NB-1 cells extensively dependent on dose and time. The IC50 of Phx-1 and Phx-3 was about 20 microM and 0.5 microM, respectively, when the cells were treated with Phx-1 or Phx-3 for 72 h. Phx-1 and Phx-3 caused the mixed types of cell death-apoptosis and necrosis-in NB-1 cells, which was detected by flow cytometry. The induction of apoptosis/necrosis caused by these phenoxazines seemed to be correlated dominantly with the caspase independent pathway, because the increased activity of effector caspase 3/7 in NB-1 cells caused by 50 microM Phx-1 or 20 microM Phx-3 was completely cancelled by the addition of z-VAD-fmk, a pan-caspase inhibitor, but such phenoxazines-suppressed viability of NB-1 cells was not recovered to normal levels by this inhibitor. The results of this study demonstrate that Phx-1 and Phx-3 have antitumor activity against the neuroblastoma cell line, NB-1, though the IC50 was extremely low for Phx-3, inducing the mixed types of cell death, apoptosis and necrosis, caspase-independently.
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PMID:Phenoxazine derivatives 2-amino-4,4alpha-dihydro-4alpha-phenoxazine-3-one and 2-aminophenoxazine-3-one-induced apoptosis through a caspase-independent mechanism in human neuroblastoma cell line NB-1 cells. 1726 75

We have previously defined a homozygously deleted region at chromosome 1p36.2-p36.3 in human neuroblastoma cell lines, NB-1 and NB-C201, and identified six genes including DFF45/ICAD within this region. In this study, we found that NB-C201 cells are much more resistant to various genotoxic stresses such as cisplatin (CDDP) than CHP134 and SH-SY5Y cells that do not have the homozygous deletion. To examine a role(s) of DFF45 in the regulation of apoptosis in response to CDDP, we have established stably DFF45-expressing NB-C201 cell clones (DFF45-1 and DFF45-3) and a control cell clone (NB-C201-C) using a retrovirus-mediated gene transfer. In contrast to NB-C201-C cells, DFF45-3 cells displayed apoptotic nuclear fragmentation in response to CDDP. Although CDDP-induced proteolytic cleavage of procaspase-3 and DFF45 in DFF45-3 cells, we could not detect a typical apoptotic DNA fragmentation. Additionally, deletion analysis revealed that C-terminal region of DFF45 is required for inducing nuclear fragmentation. Unexpectedly, (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays demonstrated that DFF45 has undetectable effect on CDDP sensitivity of NB-C201 cells. Taken together, our present results suggest that DFF45/DFF40 system may be sufficient for CDDP-induced nuclear fragmentation but not DNA cleavage.
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PMID:DFF45/ICAD restores cisplatin-induced nuclear fragmentation but not DNA cleavage in DFF45-deficient neuroblastoma cells. 1735 5

Although it has been suggested that the MYCN oncoprotein functions may influence tumorigenesis and patient survival in neuroblastoma, the mechanism of these functions remains unclear. To elucidate such molecular and biological mechanisms, we performed knock-down of MYCN expression using RNA interference (RNAi) method. MYCN-siRNAs (MYCN-siRNA) were transfected into the MYCN-amplified cell line NB-1. To verify the sequence specificity of the siRNA, we prepared three control groups (siRNA control group: siRNAs with no significant homology to any known sequences in human genome, mock control group: reagent and PBS, and the untransfected control group). The cells were analyzed by real-time RT-PCR, Western blotting, immunocytochemistry for gene expression. Cell proliferation activity was measured by WST-1 assay. TUNEL staining was performed to evaluate apoptosis. After the MYCN-siRNA transfection, the expression level of the MYCN mRNA was significantly reduced to 30% of those of the three control groups (p<0.05). Western blotting revealed an obvious reduction in MYCN protein level in the MYCN-siRNA group. On immunocytochemistry, intensity of nuclear staining of MYCN was weaker in the MYCN-siRNA group than in the three control groups. On WST-1 viability assay, cell proliferation after the MYCN-siRNA transfection was significantly suppressed compared to the three control groups (p<0.05). The TUNEL positive cells were frequently observed in the MYCN-siRNA group. Additionally, after the MYCN-siRNA transfection, the morphologic change which was suggestive of neuronal cell differentiation was observed and TrkA and TrkC expressions were also significantly up-regulated. Using RNAi method, the knock-down of MYCN expression induced growth-inhibition, apoptotic activity and cell differentiation in MYCN-amplified NB-1 cell line.
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PMID:Silencing of MYCN by RNA interference induces growth inhibition, apoptotic activity and cell differentiation in a neuroblastoma cell line with MYCN amplification. 1739 21

Exon6A of Nav1.5/SCN5A was first found in the cloning of Nav1.5 from the human neuroblastoma cell line NB-1 (Ou et al., 2005), but its expression in brain and non-brain tissue had not been identified. In this study, we have further investigated this new exon and compared it with exon6 of Nav1.5/SCN5A. Reverse transcription-polymerase chain reaction (RT-PCR) and sequence analysis both confirmed that it is exon6A that encodes Nav1.5 in brain tissue, and it is exon6 that encodes Nav1.5 in non-brain tissue. The expression of exon6A in different parts of the brain is different, with expression levels in the order of hippocampus > cerebral cortex > brain stem > cerebellum. Different expression levels of exon6 in different tissues of Wistar rats were also found. These results suggest that exon6A is unique in encoding the Nav1.5 channels in the central nervous system. In addition, novel alternative splicing of Nav1.5/SCN5A, lacking exon24, was first found in our study. This alternative splicing was also found in other tissues, such as heart, lung and testis. However, the ratio of the two variants changed differently in different types of tissues in developing rats. These results suggest that Nav1.5/SCN5A has a newly identified alternative splicing, and the Nav1.5 channels in the brain are encoded by new variants of Nav1.5/SCN5A.
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PMID:New variants of Nav1.5/SCN5A encode Na+ channels in the brain. 2138 Dec 55


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