Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recent studies using solid-phase-binding assays and electron microscopy suggested the presence of a heparin-binding domain between the inner globule of a lateral short arm and the cross region of laminin. Using the information from the amino acid sequence of the B1 chain of laminin, several peptides were synthesized from areas with a low hydropathy index and a high density of lysines and/or arginines. One of these, peptide F-9 (RYVVLPRPVCFEKGMNYTVR), which is derived from the inner globular domain of the lateral short arm, demonstrated specific binding to heparin. This was tested in direct solid-phase binding assays by coating the peptide either on nitrocellulose or on polystyrene and in indirect competition assays where the peptide was in solution and either laminin or heparin was immobilized on a solid support. The binding of [3H]heparin to peptide F-9 was dramatically reduced when heparin but not other glycosaminoglycans other than heparin (dextran sulfate, dermatan sulfate) were used in competition assays. Modification of the free amino groups of peptide F-9 by acetylation abolished its ability to inhibit the binding of [3H]heparin to laminin on polystyrene surfaces. Peptide F-9 promoted the adhesion of various cell lines (melanoma, fibrosarcoma, glioma, pheochromocytoma) and of aortic endothelial cells. Furthermore, when peptide F-9 was present in solution, it inhibited the adhesion of melanoma cells to laminin-coated substrates. These findings suggest that peptide F-9 defines a novel heparin-binding and cell adhesion-promoting site on laminin.
 ...
PMID:A novel synthetic peptide from the B1 chain of laminin with heparin-binding and cell adhesion-promoting activities. 341 82

During 1983 and 1984, 240 newly diagnosed cases of brain glioma and 742 controls (465 non-glioma nervous system tumors and 277 patients with other neurologic diseases) were recruited and interviewed in the neurologic and neurosurgical departments of two hospitals in Milan, Italy. The occupational histories of cases and controls were compared, and relative risk estimates, adjusted for sex, age, residence, and socioeconomic status, were computed using the Mantel-Haenszel method. A statistically significant risk increase was found for farmers (relative risk (RR) = 1.6, p = 0.0025). This risk increase was attributable to those farmers who reported the use of chemicals (insecticides or fungicides, herbicides, and fertilizers). Among the three groups of investigated agrochemicals, only the use of insecticides or fungicides was associated with a significant increase in relative risk (RR = 2.0, p = 0.006). Many farmers exposed to fungicides reported the use of commercial compounds of copper sulfate. Some of these compounds contain methyl urea, which has a specific carcinogenic effect on the nervous system in animals. These data suggest that the occupational exposure of farmers to agrochemicals might be responsible for the observed excess risk of brain glioma in farmers.
 ...
PMID:A case-control study of brain gliomas and occupational exposure to chemical carcinogens: the risk to farmers. 342 Dec 43

Plectin is a cytoskeletal, high molecular weight protein of widespread and abundant occurrence in cultured cells and tissues. To study its molecular structure, the protein was purified from rat glioma C6 cells and subjected to chemical and biophysical analyses. Plectin's polypeptide chains have an apparent molecular weight of 300,000, as shown by one-dimensional sodium dodecyl sulfate/polyacrylamide electrophoresis. Cross-linking of non-denatured plectin in solution with dimethyl suberimidate and electrophoretic analyses on sodium dodecyl sulfate/agarose gels revealed that the predominant soluble plectin species was a molecule of 1200 X 10(3) Mr consisting of four 300 X 10(3) Mr polypeptide chains. Hydrodynamic properties of plectin in solution were obtained by sedimentation velocity centrifugation and high-pressure liquid chromatography analysis yielding a sedimentation coefficient of 10 S and a Stokes radius of 27 nm. The high f/fmin ratio of 4.0 indicated a very elongated shape of plectin molecules and an axial ratio of about 50. Shadowing and negative staining electron microscopy of plectin molecules revealed multiple domains: a rigid rod of 184 nm in length and 2 nm in diameter, and two globular heads of 9 nm diameter at each end of the rod. Circular dichroism spectra suggested a composition of 30% alpha-helix, 9% beta-structure and 61% random coil or aperiodic structure. The rod-like shape, the alpha-helix content as well as the thermal transition within a midpoint of 45 degrees C and the transition enthalpy (168 kJ/mol) of secondary structure suggested a double-stranded, alpha-helical coiled coil rod domain. Based on the available data, we favor a model of native plectin as a dumb-bell-like association of four 300 X 10(3) Mr polypeptide chains. Electron microscopy and turbidity measurements showed that plectin molecules self-associate into various oligomeric states in solutions of nearly physiological ionic strength. These interactions apparently involved the globular end domains of the molecule. Given its rigidity and elongated shape, and its tendency towards self-association, plectin may well be an interlinking element of the cytoskeleton that may also form a network of its own.
 ...
PMID:Structure and hydrodynamic properties of plectin molecules. 343 Jun 17

We have studied the in vitro antitumor effectiveness of murine lymphokine-activated killer (LAK) cells induced by recombinant IL-2 (rIL-2). LAK cells were generated by placing 5 X 10(7) fresh C 57 BL/6 splenocytes (erythrocytes were lysed osmotically) in 10-cm (diameter) dishes (Falcon) containing 10 ml of complete medium (CM). The CM consisted of RPMI 1640 with 0.1 mM non-essential amino acids, 1 microM sodium pyruvate, 5 X 10(-5)M 2-mercaptoethanol, 50 micrograms/ml gentamicin sulfate, 0.03% glutamine, 10% heat-inactivated fetal calf serum (FCS) and 10 units/ml of rIL-2 (TGP-3, provided by TAKEDA Chemical Industries, Ltd). The dishes were incubated horizontally at 37 degrees C in a 5% CO2 atmosphere for 72-96 hr. The LAK cells were then harvested, washed three times, and resuspended in RPMI 1640 with 5% heat-inactivated FCS for the in vitro cytotoxicity assay. The antitumor cytotoxic activity of LAK cells was estimated in triplicate by 4 hr 51Cr release assays. The cytotoxic activity of LAK cells against syngeneic 203 glioma and normal syngeneic glioblasts was approximately 50% and a few %, respectively. The in vitro cytotoxicity of LAK cells against syngeneic EL-4 thymoma, allogeneic YAC-1 lymphoma and P-815 mastocytoma was 72%, 87% and 43%, respectively. Thus LAK cells have apparent tumor specificity in vitro and are easily generated. Fresh splenocytes of CBA/J mice were markedly lytic for natural killer (NK)-sensitive YAC-1 cells, but not for 203-glioma cells or NK-resistant P-815 cells.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:[The in vitro antitumor effectiveness of murine lymphokine-activated killer (LAK) cells induced by recombinant IL-2]. 348 67

The expression of epidermal growth factor (EGF-R) in normal glial and glioma cells grown in culture was examined by using several independent assays. Immunoprecipitation with the monoclonal antibody R1 of extracts from metabolically labeled glial and glioma cells revealed a protein of Mr approximately 170,000, with a migration in sodium dodecyl sulfate-polyacrylamide gels identical to the EGR-R of A431 epidermal carcinoma cells. Furthermore, in the majority of glioma extracts, a protein of Mr approximately 190,000 was specifically immunoprecipitated by this antibody. Similar results were obtained by immunoblotting with a second antibody directed against a synthetic peptide in the sequence of the v-erb-B oncogene. In cell lines expressing both proteins, each was specifically phosphorylated on tyrosine in immune complex kinase assays. The majority of glioma cells bound between 40,000 to 80,000 125I-labeled epidermal growth factor molecules per cell. These results suggest that the expression of EGF-R is common in cultured human glioma cells. In addition, a structurally related protein, is expressed in some of these cells.
 ...
PMID:Expression of epidermal growth factor receptor and associated glycoprotein on cultured human brain tumor cells. 353 68

A case of recurrent and metastasizing subcutaneous myxopapillary ependymoma of the sacrococcygeal region in a 44-year-old man is reported. The tumor was characterized light microscopically by numerous papillary projections, lined by epithelium-like cells, with a variable degree of polymorphism. Histochemical analysis relating to glucosaminoglycans indicated the presence of hyaluronic acid and chondroitin-4- and/or 6-sulfate. Using immunoperoxidase techniques, glial fibrillary acidic protein (GFAP) and S-100 protein were demonstrated within the tumor cells. Ultrastructurally, the tumor cells were characterized by an abundance of intermediate cytoplasmic filaments, prominent interdigitating cytoplasmic projections, the formation of desmosomes and external lamina-like material. The growth pattern in the tissue culture of this tumor is described, and the ultrastructural appearance of the cultured cells revealed features similar to the primary and recurrent tumor. Chromosome analyses by the G-banding technique of early generations of cultured tumor cells revealed a normal diploid stemline without gross chromosomal deviations. Among the different variant cells and clones recorded, those with X chromosome deviations were of special interest since gonosomal deviations have previously been observed in other types of glioma. The differential diagnosis against adenopapillary carcinoma, chordoma and malignant teratoma is briefly discussed.
 ...
PMID:Metastasizing myxopapillary ependymoma of the sacrococcygeal region. A clinico-pathologic, light- and electronmicroscopic, immunohistochemical, tissue culture, and cytogenetic analysis of a case. 371 5

Glycosaminoglycans (GAGs) were isolated, separated by electrophoresis and quantified in 36 neurosurgical specimens of human gliomas and in 8 samples of normal white and gray matter. Gliomas of various degrees of malignancy exhibited different GAG patterns. Total GAG concentration was three times higher in low grade gliomas than in normal white matter. The mean percentage of single GAG classes was usually similar in both tissues, although in certain tumor samples a higher percentage of hyaluronate was found. GAG patterns in anaplastic astrocytomas, however, more closely resembled normal white and gray matter, both quantitatively and qualitatively. Glioblastomas, on the other hand, showed high GAG concentrations, in particular of heparan sulfate and dermatan sulfate. This finding could be secondary to the abundant vessels and mesodermal material associated with this oncotype. The hyaluronate/sulfated GAGs ratio was lower in oligodendrogliomas than in low grade astrocytomas. This biochemical feature may be correlated with the alcianophilia found in the honey-comb degeneration of oligodendrogliomas. The significance of these findings as they relate to tumor histology and biology have been discussed.
 ...
PMID:Glycosaminoglycan changes in human gliomas. A biochemical study. 374 84

Rubrophilin, a unique brain specific polypeptide, was purified to apparent homogeneity from microsomal fractions of bovine brains. The peptide stains pink with Coomassie Brilliant Blue R-250 (C.I. No. 42660) under specific conditions, has an apparent Mr of 53,000, and is acidic with an apparent pI of 4.9. The purification involves initial solubilization of delipidated microsomes in sodium dodecyl sulfate, followed by ammonium sulfate fractionation, reversed ammonium sulfate gradient elution from diatomaceous earth, gel filtration on polyacrylamide (Biogel P-200), gradient elution chromatography from hydroxylapatite, and reverse-phase chromatography from phenyl-Sepharose. A yield of about 5 mg of rubrophilin was obtained from 9 g of microsomal proteins. Amino acid analysis shows that rubrophilin contains only nine amino acids with residues/mol as follows: alanine (102), glutamic acid (97), lysine (65), proline (55), aspartic acid (48), glycine (44), serine (37), threonine (35), and valine (10). Cysteine, methionine, tryptophan, tyrosine, isoleucine, phenylalanine, histidine, and arginine could not be detected. Relative rubrophilin content of vertebrate brains was as follows: mammals greater than birds greater than reptiles greater than fishes. It is present in mouse retina and human neuroblastoma cell cultures but could not be detected in octopus optic lobe or in cultured C-6 rat glioma cells.
 ...
PMID:Purification and properties of rubrophilin: a novel brain specific membrane polypeptide. 380 7

The possibility of fibronectin production by C6 glioma cells was examined with assays which require protein synthesis. Proteins produced by C6 cells using radiolabeled amino acid precursors were tested for affinity to collagen by binding to immobilized gelatin. The predominant collagen binding protein made by C6 coelectrophoresed with fibronectin synthesized by control fibroblasts and with the larger of the two proteins in unlabeled fibronectin when applied to polyacrylamide gels with sodium dodecyl sulfate (SDS). In addition, C6 produced a larger collagen binding protein of approximately 270,000 molecular weight. Solubilities in urea solutions of the collagen-binding proteins made by C6 cells and fibroblasts were similar. Immunofluorescence showed fibronectin associated with the C6 cell monolayer, but less abundant than the fibronectin associated with fibroblasts. Results provide evidence for the production of fibronectin by the C6 glioma cell line.
 ...
PMID:Products of cultured neuroglial cells: II. The production of fibronectin by C6 glioma cells. 389 49

Insulin receptors were detected in a variety of rat neuroblastoma and glioma cell lines. The binding of 125I-insulin to B103 neuroblastoma cells had characteristics typical of insulin receptors in other tissues, including high affinity for insulin, low affinity for insulin-like growth factor I (IGF-I), and curvilinear Scatchard plots. Using photoaffinity labeling procedures and sodium dodecyl sulfate (SDS) gel electrophoresis to analyze the subunit structure of insulin receptors in B103 cells, the predominantly labeled protein had an apparent molecular weight of 125K and the mobility of this protein was shifted after removal of sialic acid residues. On the basis of size and susceptibility to neuraminidase, the insulin binding subunit in neuroblastoma cells was identical to the alpha-subunit of insulin receptors in adipocytes and different from the 115K subunit found in brain. The presence of an "adipocyte" form of the insulin receptor in clonal cells derived from brain is probably a consequence of transformation and results from more extensive oligosaccharide processing of the 115K receptor expressed in normal brain cells. The fully glycosylated receptors in neuroblastoma cells were capable of exerting functions typical of insulin receptors in adipocytes such as internalization of insulin and stimulation of glucose transport.
 ...
PMID:Structural and functional characteristics of insulin receptors in rat neuroblastoma cells. 390 Feb 95


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