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)

Ganglioside GM1 promoted neuritogenesis of neuroblastoma cells, neuro-2a clone, in monolayer culture. GM1 bound to neuro-2a cells in three distinct forms, one removable by treatment with serum-containing solutions, one serum-resistant and labile to trypsin treatment, and one resistant to serum and trypsin treatments. The proportions among the three forms of cell-associated GM1 varied in relation to duration of exposure to ganglioside, ganglioside concentration in the medium, and number of cells in culture. The form removable by serum was predominant at the initial stages of association and at the highest ganglioside concentrations (over 10(-6)M); the trypsin-labile and -stable forms tended to increase with increasing cell number and decreasing ganglioside concentration. The neuritogenic effect of GM1 was higher when neuro-2a cells were incubated for 24 h in the presence of GM1 and fetal calf serum. Under this condition the percentage of neurite-bearing cells increased from 11% of control to 62% at the optimal ganglioside concentration of 10-4M. The effect was still present, although to a lower extent (from 11% to 28% of neurite-bearing cells), when cells were first exposed for only 2 h to GM1, then washed and incubated for 24 h in the presence of fetal calf serum. The trypsin-labile and -stable forms of cell-associated GM1 had a fundamental role in the effect, whereas the form removable by serum was not involved. The preparation of GM1 used was extremely pure (99%) and, in particular, had a peptide contamination, if any, less than 1:20,000-1:50,000.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Promotion of neuritogenesis in mouse neuroblastoma cells by exogenous gangliosides. Relationship between the effect and the cell association of ganglioside GM1. 669 71

The N-CAMs are a group of surface glycoproteins involved in adhesive interactions of neurones. Related molecules of the mouse nervous system, identified in our laboratory, have been called BSP-2 and shown to act as ligands in adhesion of neuroblastoma cells. Results presented in this report show that they are immunochemically identical with N-CAM. A monoclonal anti-(N-CAM) antibody, that recognized a determinant accessible only after permeabilization of intact cells, was used to define the mode of association of the N-CAMs with the plasma membrane. This antibody bound a 35 000-Mr fragment in lysates of trypsin-treated neuroblastoma cells. It is concluded that the antibody reacts with a transmembrane or cytoplasmic domain of the molecules. The same antibody recognized the Mr-180 000 and Mr-140 000 proteins but not the Mr-120 000 chain, which co-purify from adult mouse brain. The latter polypeptide was detected in the cytosol and could be partially released from brain membranes by osmotic shock. Part or all of the Mr-120 000 protein may thus lack a transmembrane segment. Our conclusion that the N-CAM forms of higher Mr are transmembrane proteins was further corroborated by our finding that they contain phosphoserine residues, which can be labeled with (32P)phosphate in intact neuroblastoma cells.
 ...
PMID:Studies on the transmembrane disposition of the neural cell adhesion molecule N-CAM. A monoclonal antibody recognizing a cytoplasmic domain and evidence for the presence of phosphoserine residues. 674 67

Sera from patients with progressive systemic sclerosis were compared with sera from normal individuals and from patients with other connective tissue diseases for cytotoxic effects on cultured human cells. More than 40% of the sera from patients with active progressive systemic sclerosis were cytotoxic by several criteria for pulmonary arterial or umbilical venous endothelial cells, foreskin fibroblasts, and neuroblastoma cells. Cytotoxic sera caused morphologic changes, uptake of trypan blue dye, and a decrease in the incorporation of 3H-thymidine into DNA. In contrast, only 4 sera from normal individuals or patients with other rheumatic diseases affected cell morphology, staining, or uptake of 3H-thymidine. Partial characterization of the cytotoxic factor indicated that it is sensitive to proteolysis by trypsin. The molecular weight of the factor was estimated to be similar to that of albumin.
 ...
PMID:Cytotoxicity of sera from patients with scleroderma. Effects on human endothelial cells and fibroblasts in culture. 682 14

13C n.m.r. and thin-layer chromatography were used to monitor the degradation of methionine-enkephalinamide in the presence of neuroblastoma x glioma hybrid cells (NG 108-15) and membranes. Puromycin and trypsin treatment failed to protect enkephalinamide from degradation over long periods of time (up to 24 hours). The major degradation products of [3[2-13C]glycine] methionine-enkephalinamide observed by 13 C n.m.r. showed glycine-3 in a non-terminal position, an N-terminal position and free glycine. A minor component showed glycine-3 in a C-terminal position.
 ...
PMID:Degradation of enkephalin and enkephalinamide by neuroblastoma x glioma hybrid cells as studied by 13C n.m.r. 721 24

In an effort to minimize subjective bias, a classification scheme was devised to assess Giemsa staining patterns obtained with experiments involving acetic acid-alcohol and exogenously applied histone 1 and polypeptides. A single rinse of metaphase preparations with acetic acid-alcohol quantitatively reduced Giemsa dye binding. Acid-alcohol irreversibly changed the conformation of H1 and its ability to interfere with trypsin G-banding. Our results suggest that, in addition to protein extraction, acid-alcohol may alter the conformation of acid-insoluble components of metaphase chromosomes. The carboxy-terminal polypeptide (residues 73--212) from NBS cleavage of H1 was an effective inhibitor of Giemsa staining and trypsin G-banding. However, this polypeptide which is preferential for supercoiled DNA was much less efficient in inhibiting Giemsa staining of trypsinized metaphase chromosomes. The molecular consequences of these experiments are discussed.
 ...
PMID:Effects of acetic acid-alcohol, trypsin, histone 1 and histone fragments on Giemsa staining patterns in chromosomes. 737 4

Activated platelets and stimulated endothelial cells express P-selectin, an integral membrane protein receptor that binds monocytes and neutrophils. P-selectin mediates adhesion to glycoproteins with carbohydrate structures containing sialyl-Lewis X. Since many carcinoma cells also express these carbohydrate structures and are known to interact with platelets, we asked whether P-selectin may mediate this interaction. Both small cell lung cancer and neuroblastoma cell lines bound to activated platelets, and this interaction was blocked with inhibitory anti-P-selectin antibodies and by pretreatment of these cancer cells with neuraminidase or trypsin. Platelet binding to the small cell lung cancer cells was not inhibited with anti-GP IIb-IIIa antibody or Arg-Gly-Asp-Ser peptide. Pretreatment of the neuroblastoma cells with inhibitors of N-linked carbohydrate biosynthesis had little effect on binding to P-selectin, indicating that relevant carbohydrate ligand(s) may be O-linked. In addition, lipospheres containing P-selectin specifically bound to cryostat sections derived from a small cell lung tumor and two neuroblastoma tumors, but not to sections of normal lung. These observations demonstrate that P-selectin mediates binding of platelets to small cell lung cancer and to neuroblastoma and suggest a possible role for this lectin in metastasis.
 ...
PMID:P-selectin mediates adhesion of platelets to neuroblastoma and small cell lung cancer. 768 63

Lactacystin is a Streptomyces metabolite that inhibits cell cycle progression and induces neurite outgrowth in a murine neuroblastoma cell line. Tritium-labeled lactacystin was used to identify the 20S proteasome as its specific cellular target. Three distinct peptidase activities of this enzyme complex (trypsin-like, chymotrypsin-like, and peptidylglutamyl-peptide hydrolyzing activities) were inhibited by lactacystin, the first two irreversibly and all at different rates. None of five other proteases were inhibited, and the ability of lactacystin analogs to inhibit cell cycle progression and induce neurite outgrowth correlated with their ability to inhibit the proteasome. Lactacystin appears to modify covalently the highly conserved amino-terminal threonine of the mammalian proteasome subunit X (also called MB1), a close homolog of the LMP7 proteasome subunit encoded by the major histocompatibility complex. This threonine residue may therefore have a catalytic role, and subunit X/MB1 may be a core component of an amino-terminal-threonine protease activity of the proteasome.
 ...
PMID:Inhibition of proteasome activities and subunit-specific amino-terminal threonine modification by lactacystin. 773 82

K-252a and the structurally similar compound staurosporine promote neurotrophic responses in several cell lines (PC12, SH-SY5Y human neuroblastoma) and in cultures of primary neurons. The molecular mechanisms involved in the induction of these neurotrophic activities are unknown. It is demonstrated in this report that [3H]K-252a binds to SH-SY5Y membranes and that the binding is specific and saturable with a Kd of 2.7 nM and a Bmax of 100,000 sites per cell. The association of [3H]K-252a with its binding site is rapid and reversible, and the binding was inhibited by unlabeled K-252a and by staurosporine. Binding of [3H]K-252a was not inhibited by the potent protein kinase C (PKC) inhibitor GF109203X. Down regulation of PKC by treating SH-SY5Y cells with a phorbol ester did not cause a reduction in the specific binding of [3H]K-252a to membranes, suggesting that the binding is not to PKC. Treatment of the SH-SY5Y membranes with trypsin and by boiling destroyed all specific binding of [3H]K-252a. These results suggest that the [3H]K-252a binds to a specific protein site that is associated with membranes of SH-SY5Y cells.
 ...
PMID:Membranes of human neuroblastoma SH-SY5Y cells contain specific binding sites for [3H]K-252A. 779 63

We developed an IgG1 mouse monoclonal antibody (ONS-M21) directed against a cell surface antigen of medulloblastomas and gliomas in immunisation of mice with the ONS-76 medulloblastoma cell line. The antibody specifically reacted with medulloblastomas, supratentorial primitive neuroectodermal tumours (SPNETs) and gliomas, but not with other neuroectodermally derived tumours (neuroblastoma and melanoma) or with other kinds of tumours (meningioma, neurinoma, leukaemia, and small cell lung cancer). No reactivity was identified with normal body tissues, including peripheral blood cells. Characterisation of the ONS-M21 antigen showed that it was a trypsin-sensitive glycoprotein with a molecular weight of 80 kDa on SDS-PAGE. The pattern of reactivity and the biochemical properties of this antigen were different from those of other markers of medulloblastoma. These results indicate that ONS-M21 detects a new tumour-associated cell surface antigen specifically expressed by medulloblastomas, SPNETs, and gliomas. This is the first report that medulloblastomas may share common cell surface antigens with gliomas, although most studies have concluded that medulloblastoma has a predominantly neuronal phenotype. The lack of reactivity with normal tissue implies that ONS-M21 has potential applications as both a diagnostic tool and a therapeutic agent.
 ...
PMID:Characterisation of a new mouse monoclonal antibody (ONS-M21) reactive with both medulloblastomas and gliomas. 821 97

Using immunofluorescence microscopy we found that gp120 binds to the surface of rat dorsal root ganglia neurons and human neuroblastoma cells but not to rat fibroblasts or glial cells. The binding of gp120 to neurons was eliminated by pretreatment with trypsin, which removes cell-surface proteins, but not with chloroform: methanol, which removes glycolipids. As control, neuronal staining by antisulfatide antibodies was eliminated by pretreatment with chloroform: methanol but not with trypsin. The gp120 binding to neurons was also inhibited by the mouse monoclonal antibody 01, which binds to galactocerebroside and cross-reactive glycoproteins. These studies suggest that the receptor for gp120 on the surface of the dorsal root ganglia neurons is a glycoprotein. This interaction may mediate the effects of human immunodeficiency virus type 1 in sensory neuropathy.
 ...
PMID:The gp120 glycoprotein of human immunodeficiency virus type 1 binds to sensory ganglion neurons. 825 May 36


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>