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

Five patients with glioma were examined with positron emission tomography using ([11C]methyl)-L-methionine. The study was repeated while the patient was being infused with branched chain amino acids (BCAA), 250 mumol/min. The accumulation rates of methionine in tumor tissue and in normal brain tissue were compared without and with the infusion of amino acids. Both tumor tissue and normal brain tissue showed a reduction in the methionine accumulation by 35% while the patient received the infusion. In one patient with a severe blood-tissue barrier disruption the tumor accumulation rate was unaffected. It is concluded that in gliomas without severe blood-tissue barrier disruption, the accumulation of methionine is governed by processes exhibiting similar properties regarding competition with BCAA as in normal brain tissue.
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PMID:PET study of methionine accumulation in glioma and normal brain tissue: competition with branched chain amino acids. 349 74

Five opioid peptides (immunoreactivity) derived from their respective opioid precursors were measured in neuroblastoma-glioma hybrid cells (NG 108CC15; pmol/g protein): heptapeptide (Tyr-Gly-Gly-Phe-Met-Arg-Phe), 13.0 +/- 2.6; alpha-neoendorphin, 6.6 +/- 0.8; dynorphin A, 4.4 +/- 1.5; dynorphin A 1-8, 1.3 +/- 0.29; beta-endorphin, 0.3 +/- 0.13. These peptides originate from preproenkephalin A (heptapeptide), prodynorphin (alpha-neonedorphin, dynorphin A, dynorphin A 1-8) and proopiomelanocortin (beta-endorphin). The data suggest the expression of all three known opioid precursors in a single hybrid cell line, permitting a simultaneous investigation of the processing of different opioid peptides under identical experimental conditions.
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PMID:Evidence for the expression of peptides derived from three opioid precursors in NG 108CC15 hybrid cells. 356 21

The effects of the potent tumour-promoting phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) on phosphatidylcholine (PtdCho) metabolism were investigated in the neuroblastoma X glioma hybrid cell line NG108-15. TPA (100 nM) stimulated by 150-200% the release into the medium of 3H radioactivity from cells that had been pre-labelled with [3H]choline. H.p.l.c. analysis of the medium revealed that TPA stimulated the release of only free [3H]choline (212 +/- 11% of control), without affecting such other labelled metabolites as [3H]phosphocholine and [3H]glycerophosphocholine. This effect was concentration-dependent, with a half-maximal effect obtained at 27.5 +/- 6.8 nM, and was observable as early as 5-10 min after exposure to TPA. The TPA-induced release of [3H]choline into the medium was accompanied by a small and variable decrease in cellular [3H]PtdCho (to 93 +/- 4% of control). However, the radioactivity associated with water-soluble cellular choline metabolites (mainly [3H]phosphocholine and [3H]glycerophosphocholine) remained unchanged. TPA also stimulated the release of [3H]choline derived from [3H]PtdCho that had been produced via the methylation pathway from [3H]methionine. These data suggest that phosphatidylcholine may serve as the source of free choline released from the cells in response to TPA. The possible enzymic mechanisms underlying this response are discussed.
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PMID:Stimulation of choline release from NG108-15 cells by 12-O-tetradecanoylphorbol 13-acetate. 356 13

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.
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PMID:Purification and properties of rubrophilin: a novel brain specific membrane polypeptide. 380 7

Qualitative aspects of protein synthesis in organelles and intact cultured cells of brain origin were compared to clarify the distinction between synaptosomal and mitochondrial protein synthesis. Brain mitochondria and synaptosomes were isolated either on a traditional Ficoll-sucrose gradient or by a new Percoll gradient procedure, and were incubated in an amino acid incorporation system containing [35S]methionine, then electrophoresed on gradient slab gels. Autoradiography of the gels revealed that in the presence of cycloheximide both mitochondria and synaptosomes synthesized at least 17 proteins in the 6,000-50,000 MW range, and that incubation with chloramphenicol reduced or eliminated these bands. With minor variation these patterns in the low-molecular-weight region also resembled patterns obtained from cycloheximide-inhibited rat liver mitochondria and intact brain cells (cultured glia, glioma, and neuroblastoma). In the higher molecular weight region of the gels (greater than 50,000) banding patterns were more complex and tended to differ between organelles and intact cells. These polypeptides probably reflect nonmitochondrial protein synthesis, and their variable response to inhibitors may account for confusion in the literature with regard to the effects of inhibitors of protein synthesis in brain mitochondria and synaptosomes.
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PMID:Comparison of protein synthesis in mitochondria, synaptosomes, and intact brain cells. 396 18

One hundred and seventeen patients with cerebral glioma (Kernohan grades III and IV) were treated with adjuvant chemotherapy using procarbazine (PCB), CCNU and vincristine (VCR) following whole head irradiation. Cell cultures were prepared from 40 patients in this series and their sensitivity to each cytotoxic drug was assessed in a mictotitration assay with 35 S-methionine incorporation as the end point. Twenty-two of forty (55%) patients responded to PCB and/or CCNU in vitro, and sensitivity to these drugs was linked with increased RFI, whilst sensitivity to VCR was not. The RFI of patients who had responded to PCB or CCNU in vitro was significantly longer than the RFI of patients whose tumours failed to respond in vitro or patients who had not been tested. There was no difference in sex ratio, extent of operation, radiation dose and degree of steroid cover between responders, non-responders and untested groups. Grade III tumours tended to be more sensitive in vitro than grade IV tumours. The age of patients also influenced in vitro chemosensitivity. Patients with chemosensitive tumours in vitro tended to be younger than patients with insensitive tumours in vitro. Further statistical analysis, taking into account these prognostic factors, indicated an association between chemosensitivity in vitro and RFI.
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PMID:Assay of anti-cancer drugs in tissue culture: relationship of relapse free interval (RFI) and in vitro chemosensitivity in patients with malignant cerebral glioma. 397 31

The human glioma-derived cell line D-54 MG and the human medulloblastoma-derived cell line TE-671 have been shown to be sensitive in culture to the pharmacological interference with glutamine metabolism by acivicin, 6-diazo-5-oxo-L-norleucine, and methionine sulfoximine. Using as a guide the multiple contributions of glutamine to the biosynthesis of proteins, purines, and pyrimidines, we now have identified six additional antimetabolites active against these lines in vitro at clinically relevant concentrations. The 50% growth-inhibitory levels of the drugs against D-54 MG in 6-day continuous exposure experiments were: L-asparaginase, 0.057 IU/ml; 5-fluorouracil, 0.5 micrograms/ml; 6-mercaptopurine, 0.8 micrograms/ml; actinomycin D, 0.0007 micrograms/ml; N-phosphonacetyl-L-aspartic acid, 2.3 micrograms/ml; and 5-azacytidine, 0.2 micrograms/ml (3-day exposure. The corresponding 50% growth-inhibitory values in TE-671 were: L-asparaginase, 0.54 IU/ml; 5-fluorouracil, 1.5 micrograms/ml; 6-mercaptopurine, 4.7 micrograms/ml; actinomycin D, 0.00044 micrograms/ml; N-phosphonacetyl-L-aspartic acid, 4.5 micrograms/ml; and 5-azacytidine, 0.49 micrograms/ml. Dipyridamole up to 10 micrograms/ml was inactive against both lines. The isobologram method was used to evaluate the effectiveness of several two-drug combinations which were biochemically designed. The sums of the optimal fractional inhibitory concentrations for the pairs were: acivicin plus L-asparaginase, 0.14; acivicin plus methionine sulfoximine, 0.40; 6-diazo-5-oxo-L-norleucine plus methionine sulfoximine, 0.60; acivicin plus 6-mercaptopurine, 1.0, all in TE-671; and acivicin plus 5-fluorouracil, 0.79, in D-54 MG. Our findings suggest that an antimetabolite regimen exploiting glutamine sensitivity might improve the chemotherapy of some human gliomas and medulloblastomas.
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PMID:Combination chemotherapy in vitro exploiting glutamine metabolism of human glioma and medulloblastoma. 402

The concentration of intracellular free calcium ions was measured by spectrofluorometry in suspensions of quin2 loaded neural cell lines: neuroblastoma X glioma hybrid cells (clones 108CC15 and 108CC25) and polyploid rat glioma cells (clone C6-4-2). In these cells, bradykinin elicits a transient increase of the cytosolic Ca2+-activity in a dose-dependent manner (half-maximal effect at about 10 nM). The effect requires the presence of extracellular Ca2+. The time to peak is at most 10 s, the decay to the original level lasts 1 min and is followed by a period of 1-4 min during which Ca2+ activity is slightly below control value. Lys-bradykinin and Met-Lys-bradykinin evoke similar effects as bradykinin, but at concentrations 10 times lower. The cells desensitize upon repeated addition of bradykinin. Under the same conditions des-Arg1-bradykinin, des-Arg9-bradykinin, angiotensin II, substance P, apamin and histamine exerted no influence on the concentrations of free Ca2+. Similar to their effect in neural cell lines, bradykinin and Lys-bradykinin induce in primary astroglia-rich cultures from rat brain an increase in the concentration of cytosolic Ca2+ with the peak reached within 30 s and the decay to the original level lasting approximately 4 min. The significance of this effect of bradykinin on the cytosolic Ca2+-activity is discussed in relation to previous findings that bradykinin in the same cell lines induces a hyperpolarization, a rise of the cyclic GMP level and a breakdown of phosphoinositides.
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PMID:Bradykinin causes a transient rise of intracellular Ca2+-activity in cultured neural cells. 406 82

Previous work from this laboratory described an association, based on genetic evidence, between a 68 000 dalton protein (p68) and corticotropin (ACTH) sensitive adenylate cyclase activity among variants of the Y1 mouse adrenocortical tumor cell line. To study the nature of this association further, we have purified p68 and raised a polyclonal anti-p68 serum in rabbits. A variant subclone of the Y1 line, in which p68 comprised approximately 10% of total soluble protein, was used as starting material. Purification of p68 was achieved by passage of a 100 000 X g supernatant fraction over DEAE-cellulose, fractionation with ammonium sulfate, and chromatography on hydroxylapatite. The purified protein had an isoelectric point of 7.3, a polarity value of 46%, and a blocked amino terminal end group. A rabbit antiserum raised against the purified p68 had a titer of 1:16 000 and specifically precipitated p68 from extracts of Y1 cells labeled with L-[35S]methionine. Using this antiserum, p68 also was detected in other cell lines including mouse erythroleukemia and Sertoli cells; rat Leydig, ovary, and glioma cells; and Chinese hamster ovary cells. The presence of p68 in a variety of cell types suggests that the function of p68 is not restricted to adrenal cells or to specific actions of ACTH.
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PMID:A 68 000 dalton protein genetically associated with corticotropin-sensitive adenylate cyclase activity. Purification and preliminary characterization using a specific antiserum. 608 78

Partially purified extracts from neuroblastoma X glioma hybrid cells 108CC15 inhibit, like opioids, the prostaglandin E1-evoked formation of cyclic AMP in a dose-dependent manner in the same hybrid cells. The inhibition is prevented by the opioid antagonist naloxone. In addition, the same extract competes with [3H]naloxone and [3H]Leu-enkephalin for binding to opioid receptors of hybrid cell membranes and to a specific antiserum, respectively. The opioid activity in the extracts is destroyed by carboxypeptidase A and leucine aminopeptidase, but not by trypsin. Further purification of the extracts by HPLC, TLC, or high-voltage paper electrophoresis reveals in each case two active fractions which behave like Met- and Leu-enkephalin. The Met-enkephalin-like, but not the Leu-enkephalin-like, fraction is inactivated by treatment with BrCN. Dimethylaminonaphtylsulfonyl (dansyl) derivatives of Met- and Leu-enkephalin correspond to [3H]dansyl derivatives of Met-like substances from hybrid cells. Three to four times as much Met-enkephalin-like as Leu-enkephalin-like material is present in the extract. The overall concentration of opioid peptides in the hybrid cells varies between 0.03 and 1.0 pmol Leu-enkephalin equivalents per mg protein. The amount of opioids in the hybrid cells is strongly dependent on the cell density. The findings suggest that neuroblastoma X glioma hybrid cells contain opioid peptides that are very similar, if not identical, to Met- and Leu-enkephalin. Opioid activity can also be detected in other neuronal cell lines and even in glioma cells.
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PMID:Neuroblastoma X glioma hybrid cells synthesize enkephalin-like opioid peptides. 628 22


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