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)

Mouse neuroblastoma N18 cells contain a homologous series of gangliosides (GM3, GM2, GM1, and GD1a) which constitute a biosynthetic pathway. When added to the culture medium, tritium-labeled palmitate, galactose, and N-acetylmannosamine were incorporated into these gangliosides. Incorporation of [3H]galactose into all four gangliosides was detected by 5 min and continued at essentially linear rates for several hours. When the cells were treated with Vibrio cholerae neuraminidase, the amounts of GM3 and GD1a were reduced from 72% to 85%; there was a severalfold increase in GM1 and no change in GM2. In spite of these large alterations in cellular ganglioside composition, there was no change in the rate of [3H]galactose incorporation into the gangliosides. A large proportion of GM3 and GD1a also was accessible to neuraminidase in neuroblastoma NB41A, Friend erythroleukemic, and rat glioma C6 cells. N18, NB41A, and Friend cells bound large amounts of 125I-labeled cholera toxin with high affinity. At saturation, the ratio of GM1 content to toxin bound for the three cell lines was between 5.5 and 7. When treated with neuraminidase, the cells bound more toxin in correspondence to the increase in GM1 content. As each toxin molecule has five binding sites, these results suggest that most of the GM1 in these cells is on the surface. Our results indicate that the sequential glycosylation of one ganglioside to form the next higher homologue involves a very small pool of intermediates and that the bulk of the gangliosides are on the cell surface.
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PMID:Biosynthesis and localization of gangliosides in cultured cells. 711 66

SH-SY5Y is a thrice cloned cell line originally derived from the human neuroblastoma cell line SK-N-SH. It grows well in serum-containing medium and undergoes neuritogenesis in response to several trophic factors. Because it has been reported that this clonal line does not have receptors for platelet-derived growth factor (PDGF), it has been unclear what the major mitogenic factor in serum is for these cells. In competitive binding studies using radiolabeled PDGF-BB, we found that SH-SY5Y cells specifically bind PDGF with a KD = 0.14 +/- 0.06 nM and Bmax = 7.3 +/- 2.3 pM. Functionality of these receptors was demonstrated by an increased [3H]-thymidine incorporation in response to PDGF (stimulation index = 2.5). At concentrations of PDGF-BB between 5 and 100 ng/ml, maximum stimulation occurred with 20 ng/ml. Maximum DNA synthesis occurred after 12-24-h exposure to PDGF. Gangliosides GM3 and GT1b greatly inhibited [3H]thymidine incorporation, which was also inhibited to a lesser extent by GM1. Phosphorylation on tyrosine of a 170-kDa protein in response to PDGF stimulation of intact cells was demonstrated by western blot analysis probing with anti-phosphotyrosine antibody. Immunoprecipitation with anti-PDGF beta-receptor antibody and visualization on a western blot with an anti-phosphotyrosine antibody also revealed a 170-kDa protein. Maximum phosphorylation of the 170-kDa protein occurred after 5-min exposure to 20 ng/ml PDGF. This phosphorylation was inhibited by gangliosides GM1, GM2, GD1a, and GT1b but not by GM3. Receptor dimerization was also inhibited by GM1. These results show that SH-SY5Y cells have specific receptors for PDGF-BB that are functional, and can be modulated by gangliosides.
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PMID:Gangliosides inhibit platelet-derived growth factor-stimulated growth, receptor phosphorylation, and dimerization in neuroblastoma SH-SY5Y cells. 759 14

We have examined ganglioside compositions and the presence of sulfated glucuronyl glycolipids of immortalized motor neuron-like cell lines, neuroblastoma-spinal cord (NSC) hybrid cell lines established by fusing mouse neuroblastoma N18TG2 with motor neuron-enriched embryonic spinal cord cells. Among NSC cell lines, only NSC-34 aggregates acetylcholine receptors on co-cultured myotube and expresses a receptor for S-laminin, a neuromuscular junction specific basal lamina protein. GM2, which is only a minor ganglioside component of CNS, was the major component in NSC-34 occupying almost 75% of total gangliosides, whereas GD1a and GM3 were major species in the parental N18TG2, which had only 8.5% GM2. These results indicated that NSC lines have unique ganglioside pattern that is distinctive from other nervous tissues, and this pattern, especially that of NSC-34 cells, might reflect the characteristics of mouse spinal motor neuron gangliosides. Sulfated glucuronyl paragloboside was demonstrated to be present in N18TG2, however, it could not be detected in either of NSC cell lines. Even though the pathogenesis of amyotrophic lateral sclerosis remains unknown, autoimmunological participation has been suggested. Because high-titered antibody against GM2 has been observed in a patient with amyotrophic lateral sclerosis-like disease, GM2 which is possibly expressed on the surface of motor neurons might serve as a potential target antigen in this disorder.
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PMID:Ganglioside characterization of a cell line displaying motor neuron-like phenotype: GM2 as a possible major ganglioside in motor neurons. 759 35

SH-SY5Y Neuroblastoma cells were used to study the effect of retinoic acid (RA)-induced differentiation on the expression of gangliosides and neuronal markers. In the presence of 10 microM RA, more than 70% of the cells differentiate to a neuronal phenotype within 8 days. They extend long neuritic processes and show an enhanced immuno-expression of neurone-specific enolase (NSE), neurofilament protein (NF-M), and polysialic acid (PSA). SH-SY5Y cells were found to express at least 12 different gangliosides. RA-induced neuronal differentiation led to a decrease in the content of GM2, GD3, and GD2 and to a 3-7 fold increased concentration of the ganglio-tetraosyl gangliosides GM1, GD1a, GT1a, GD1b, and GT1b. Thus, RA-induced neuronal differentiation of SH-SY5Y cells is accompanied by ganglioside changes similar to those observed during embryonic neuronal differentiation.
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PMID:Altered ganglioside expression by SH-SY5Y cells upon retinoic acid-induced neuronal differentiation. 806 1

The role of cell surface GM1 ganglioside in neurite outgrowth of Neuro-2a neuroblastoma cells was investigated by application of anti-GM1 antibody and the B subunit of cholera toxin (cholera B) to cultured cells stimulated to grow neurites in various ways. When the cells were simultaneously treated with stimulatory agent and cholera B, inhibition, as measured by percent of neurite-bearing cells, was observed with most stimuli: neuraminidase; GD1a ganglioside, retinoic acid, and low serum. However, with dibutyryl cyclic AMP the small reduction observed was not statistically significant. The inhibitory effect of cholera B on neurite outgrowth induced by low serum was dose-dependent, reaching a maximum at 200 ng/mL; 48 h after washout of cholera B the cells were released from inhibition and regrew neurites at nearly the previous rate in the presence of low serum. When the cells were exposed to stimulus for 6 h or more the inhibitory effect of subsequent addition of cholera B was reduced or eliminated; inhibition thus occurs during an early stage of neurite initiation. Anti-GM1 antibody at dilutions of 1:100-1:400 had the same inhibitory effect as cholera B with cells stimulated by GD1a or retinoic acid, whereas anti-GM2 antibody had no effect at 1:200 or 1:400; inhibition by the latter antibody at 1:100 dilution was similar to that attained with control ascites fluid. These results point to a pivotal role for cell surface GM1 in Neuro-2a differentiation induced by many (but not all) neuritogenic agents.
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PMID:Inhibition of neurite outgrowth of neuroblastoma Neuro-2a cells by cholera toxin B-subunit and anti-GM1 antibody. 808 37

Cell surface gangliosides are potent modulators of cellular proliferation. We hypothesize that gangliosides shed by tumor cells modulate hematopoiesis and contribute to human tumor-associated suppression of hematopoiesis. To test this hypothesis, we determined the effects on myeloid colony formation by human bone marrow mononuclear cells of total gangliosides isolated from human brain and of seven highly purified individual ganglioside species (GM1, GM2, GD1a, GD1b, GD2, GD3, and GT1b). Total human brain gangliosides and certain individual species, GD1a, GD1b, and GT1b, significantly inhibited myeloid colony formation (number as well as size). The most complex molecules, GD1a, GD1b, and GT1b, were the most inhibitory, suggesting that the degree of inhibition is related to ganglioside structural complexity. To extend these findings, we also investigated certain tumor-derived (neuroblastoma) gangliosides, which we found inhibited both myeloid colony formation and 3H-thymidine incorporation by human bone marrow mononuclear cells. These data suggest a role for gangliosides, which are shed by proliferating cells, in the regulation of human hematopoiesis and may explain the bone marrow hypoplasia observed in association with many human malignancies.
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PMID:Modulation of human myelopoiesis by human gangliosides. 828 59

The fate of anti-tumor monoclonal antibodies (mAbs) after binding to the cell surface is one of the important factors for application of mAbs in therapy. For mAbs to remain on the cell surface for a long time is preferable character for complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC). On the other hand, quick internalization of mAbs into cytoplasm is advantageous for cytotoxic effects of toxins or cytotoxic drugs conjugated with mAbs. In this study we investigated the localization of anti-carbohydrate mAbs in vitro by immunocytochemical methods at the electron microscopic level. Anti-ganglioside GM3 mAb (mouse IgM) was localized both in cytoplasmic vesicles and on the cell surface membrane of mouse melanoma cells after incubation for 30 min at 37 degrees C. Anti-ganglioside GM2 mAb (mouse IgM), anti-ganglioside GD2 mAb (mouse IgG3) anti-ganglioside GD3 mAb (mouse IgG3) mainly existed on the cell surface of human small cell lung carcinoma cells, human neuroblastoma cells and human melanoma cells, respectively, after incubation for 30 min at 37 degrees C. On the other hand, anti-sialyl Lea mAb (mouse IgG1) was intensively incorporated into the cytoplasm of human colon tumor cells under the same conditions. Anti-ganglioside GD3 mAb and anti-sialyl Lea mAb were radiolabelled with 125Iodine and traced in in vitro culture. When the cells were incubated in the presence of the 125I-mAb for 90 min on ice, the ratio of intracellular counts to surface counts was 8/92 for anti-ganglioside GD3 mAb and 31/69 for anti-sialyl Lea mAb respectively. After the subsequent incubation for 60 min at 37 degrees C, the ratio altered to 13/87 for anti-ganglioside GD3 mAb and 54/46 for anti-sialyl Lea antigen mAb. This study suggested that internalization of anti-carbohydrate mAbs after the binding to the cell surface was different among the mAbs depending on the character of antigens. In conclusion, anti-ganglioside mAbs have beneficial characters for CDC or ADCC while anti-sialyl Lea mAb is suitable for immunoconjugates.
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PMID:Immunocytochemical study on internalization of anti-carbohydrate monoclonal antibodies. 829 35

The cytolytic Clostridium perfringens delta toxin lyses selectively cells which express ganglioside GM2. In this study, we investigated whether delta toxin can be used to characterize GM2 on tumor cell membranes and as an antitumor agent. The sensitivity to lysis by delta toxin of various murine and human malignant cell lines and also normal tissues was quantified using a 51Cr-release assay. The cytotoxicity titers were correlated with the 125I-labeled toxin binding capacity of sensitive and insensitive cells. Seven of eight human melanomas tested were lysed by the toxin and, of these, four were very sensitive (cytotoxicity titers below 12 ng of toxin). All neuroblastomas, gliomas and the retinoblastoma tested were lysed with 3-18 ng of toxin. Three of six carcinomas and one of two sarcomas were also very sensitive (cytotoxicity titers 0.6-15 ng) whereas leukemias and lymphoma cells were insensitive. Normal human tissues were insensitive (erythrocytes, skin fibroblasts) or poorly sensitive (brain, lung, spleen). The in vivo antitumor activity of delta toxin was tested in tumor-bearing mice. Daily intra-tumor injections of 0.5-1 mg of toxin for 4-5 days in carcinoma Me180- and melanoma A375-bearing nude mice, and neuroblastoma C1300-bearing A/J mice significantly inhibited tumor growth for 12-36 days. Intravenous administration of 100 ng of toxin per day for 5 days in Me180-bearing nude mice and C1300-bearing A/J mice gave significant inhibition of tumor growth only during the treatment period, and 10 injections of the same dose of toxin had no significant effect on SK-MEL28, a tumor lacking GM2.
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PMID:Targeting of GM2-bearing tumor cells with the cytolytic Clostridium perfringens delta toxin. 845 17

GM2 and GD2 have been intensely studied as tumor antigens of neuroectodermal-origin tumors. We have established several mouse or rat IgM anti-ganglioside GM2 and GD2 MoAbs and applied them in antigen-specific drug delivery. In the immunofluorescence assay, anti-GM2 MoAbs bound to neuroblastoma cells and leukemia cells, and anti-GD2 MoAb bound to neuroblastoma cells and melanoma cells. Sulfhydryl subunits of reduced IgM were directly coupled to maleimide groups on the surface of the liposomes followed by the incorporation of adriamycin by the use of Na+/K+ chemical gradient. The resultant immunoliposomes had a size of 86 nm-diameter containing approximately 400 molecules of adriamycin in its unilamellar structure and 17 molecules of the MoAb on its surface. Mouse anti-GM2 MoAb lost the binding specificity when covalently bound to the liposomes. The immunoliposome coupled with mouse anti-GD2 MoAb retained targeting activity to the antigen-positive neuroblastoma cells, IMR-32. However, it did not kill IMR-32 cells, probably because the amount of adriamycin taken up by the tumor cell was below the fatal amount. The immunoliposome coupled with rat anti-GM2 MoAbs delivered adriamycin to the neuroblastoma cells, IMR-32, and leukemia cells, TYH, in the antigen-specific manner. It also target-specifically suppressed the (3H)thymidine-uptake of the cells while the same concentration of adriamycin in the free form killed all the cell lines examined. IMR-32 cells had GM2 and GD2 in almost the same amounts, and interacted with either mouse anti-GD2 MoAb--immunoliposome or rat anti-GM2 MoAb-immunoliposome. The different cytotoxic activities of the two immunoliposomes against IMR-32 cells was probably due to the difference in the facility of internalization of the immunoliposomes after binding.
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PMID:Cytotoxicity of adriamycin-containing immunoliposomes targeted with anti-ganglioside monoclonal antibodies. 851 45

Neurotransmission is dependent on the presence of neuronal receptors at the synapses, and important cell surface molecules such as gangliosides are pivotal in the maintenance of synaptic contacts. To study the interrelationship between these two classes of molecules, we achieved stable expression of the hippocampus- and CNS-localized serotonin 1A receptor (5-HT1A-R) in three 5-HT1A-R-deficient neuronal cell lines and also the control, non-neural CHO cells. A strong passage dependence of 5-HT1A-R expression, as measured by mRNA levels as well as membrane binding to the selective agonist [3H]8-OH-DPAT, was observed only in the HN2 (hippocampal) and NCB-20 (CNS) cells which are derived from tissues of natural occurrence of the 5-HT1A-R. A paradigm of stress was obtained by carrying out continuous culture of cells without feeding. During this time a dramatic increase in 5-HT1A-R mRNA and [3H]8-OH-DPAT binding was observed only in the neuronal cells after confluence and during decreased cell viability (days 10/11). This was not due to differentiation, since deliberate serum deprivation and differentiation of cells did not result in any dramatic increase in 5-HT1A-R expression. Analysis of ganglioside synthesis by pulse labeling of the transfected cells produced striking results. In the dorsal root of the ganglion (DRG) derived F-11 cells which show low but significant levels of complex gangliosides before transfection, the mere presence of the serotonin 1A receptor resulted in a dramatic increase in synthesis of gangliosides comigrating with GM2, GD1a, GD1b, and GT1b (20-fold by densitometry). In contrast, there was only a 2-fold increase in the overall content of complex gangliosides in the presence of the 5-HT1A-R. In the NCB-20 cells which contain only GD1a but no GD1b or GT1b before transfection, a decrease in GD1a synthesis was observed following transfection. Also agonist (8-OH-DPAT) binding to the serotonin 1A receptor in NCB-20 cells produced a 3-fold increase in synthesis of a ganglioside comigrating with GM3. Thus, our neuroblastoma transfectants help demonstrate stress-induced regulation of the 5-HT1A-R, which in turn exerts a strong and cell type-specific control over such essential cell-surface determinants like gangliosides.
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PMID:Cell-specific regulation of the stably expressed serotonin 5-HT1A receptor and altered ganglioside synthesis. 861 34


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