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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The establishment of a new glioma cell line, DBTRG-05MG, in a modified RPMI 1640 medium is described. The cells were derived from an adult female with glioblastoma multiforme who had been treated with local brain irradiation and multidrug chemotherapy; the tumor showed substantial change in histologic appearance compared to the original biopsy 13 mo. previously. The line has been successfully cryopreserved and passaged up to 20 times. The karyotype of the cells demonstrated it as a hypotetraploid line; the DNA index of 1.9 confirmed the karyotype analyses. By immunocytochemical analysis, the cell line reacted with polyclonal antibodies to vimentin, S100, and neuron specific enolase, reflecting its primitive neuroectodermal character. Positive immunostaining for epidermal growth factor receptor correlated with the excess of chromosome 7 seen in the karyotype. The cell line reacted negatively to antibodies against platelet-derived growth factor and its receptor, neuronal cell adhesion molecule, and glial fibrillary acidic protein. By flow cytometry, the cells were major histocompatibility class I antigen positive and class I antigen negative. Growth kinetic studies demonstrated an approximate population doubling time of 34 to 41 h and a colony forming efficiency of 71.4%. Western blot analysis showed the presence of low levels of normal-sized retinoblastoma protein. When compared to the patient's lymphocyte DNA, no loss of heterozygosity of the p53 tumor suppressor gene was observed in the DBTRG-05MG cell line DNA.
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PMID:Characterization of a continuous human glioma cell line DBTRG-05MG: growth kinetics, karyotype, receptor expression, and tumor suppressor gene analyses. 133 Oct 21

The influence of the neurotoxic agents lead and cadmium on human glioma cells (86HG-39, 87HG-31, 88HG-14, and A172) and rat glioma cells (F98 and RG2) was investigated in vitro by means of immunocytochemistry and growth data. Both heavy metals increased the growth rate, decreased the expression of differentiation markers (glial fibrillary acidic protein, S100 protein), and increased the expression of the malignancy marker transferrin receptor. The results indicate a decrease in the level of differentiation and impairment of glial cell function. Consequently, the neurotoxicity of Pb and Cd may be attributed to direct action not only on neurons but also on glial cells necessary for neuronal function. Possible molecular mechanisms are discussed.
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PMID:Modulation of glial cell differentiation by exposure to lead and cadmium. 152 29

'Gliosarcomas' have long been considered to be mixed gliomas and sarcomas. The present study failed to define criteria which clearly delineate 'gliosarcomas' from glioblastoma multiforme and suggests that 'gliosarcomas' should be considered as spindle cell glioblastomas. A total of six cases originally diagnosed as 'gliosarcomas' were compared with four cases of glioblastoma multiforme. No clinical or prognostic features were defined which would clearly separate 'gliosarcomas' from glioblastoma multiforme. Macroscopically, biopsies from 'gliosarcomas' ranged from firm, apparently well-circumscribed tumours to poorly circumscribed lesions with a soft consistency resembling glioblastoma multiforme. Histology revealed a continuous spectrum in which 'gliosarcomas' with large reticulin-rich areas of spindle cells merged with typical glioblastomas containing only small islands of spindle cells and reticulin staining. Immunocytochemistry for glial fibrillary acidic protein (GFAP); S100 protein and alpha-smooth muscle actin (ASMA) showed that the majority of cells in reticulin-poor areas of 'gliosarcoma' and glioblastomas expressed S100 protein and GFAP; many expressed ASMA and some expressed both GFAP and ASMA. Spindle cells in reticulin-rich areas of 'gliosarcomas' and glioblastomas most frequently expressed ASMA but many cells also expressed S100 protein and GFAP; some cells expressed both GFAP and ASMA. The results of this study and a review of the literature suggests that there is a clinical, radiological and pathological continuum with glioblastoma and 'gliosarcoma' at different ends of the spectrum. It is suggested, therefore, that most, if not all, 'gliosarcomas' be redesignated as spindle cell glioblastomas and not be considered as a mixture of glioma and sarcoma.
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PMID:Spindle-cell glioblastoma or gliosarcoma? 162 Feb 80

The human glioblastoma-derived cell lines 86HG-39, 87HG-28 and 87HG-31, used for the production of monoclonal antibodies (mAbs) against glioma-associated antigens (GAA), were characterized in terms of morphology, growth behaviour, chromosomes and antigen expression. In the primary tumours, differential expression of glial fibrillary acidic protein, S100 protein, Leu-7 and GAA as defined by mAbs MUC 2-39, MUC 2-63 and MUC 8-22 was demonstrated. Receptors for epidermal growth factor (EGFr) and nerve growth factor (NGFr) were found in many cells in short-term cultures, but the transferrin receptor (Tr) was found in only a few cells of 87HG-28. In permanent cell lines, differentiation antigens and EGFr decreased and Tr increased markedly. NGFr and GAA remained stable. Transplantation tumours of 86HG-39 were partly positive for Tr and GAA. Chromosomal analysis revealed that the 86HG-39 and 87HG-28 cell lines had a hypodiploid or diploid stem line with lines in the hypotetraploid to tetraploid region for 50 in vitro passages. The 87HG-31 cell line had chromosomal patterns in the hypotriploid to triploid region. A gain of chromosomes was seen in the groups C7, C8, C10, D14, F19, F20, G21, G22. The variability of antigens in these tumours and especially during long-term cultivation probably reveals an ability to influence the growth of malignant glioma cells via the respective effector molecules.
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PMID:Morphological, immunocytochemical and growth characteristics of three human glioblastomas established in vitro. 170 26

Nervous system development involves a coordinated series of events, including regulation of cell proliferation and differentiation by specific extracellular factors. S100 beta is a neurotrophic protein that has been implicated in regulation of cellular proliferation, but direct evidence was lacking. In this report, nanomolar concentrations of S100 beta are shown to stimulate proliferation of rat C6 glioma cells and primary astrocytes. An S100 mutant with a single amino acid change was inactive. S100 beta also stimulated increases in the steady-state levels of c-myc and c-fos protooncogene mRNAs and complemented the effects of platelet-derived growth factor. Two neuroblastoma cell lines did not proliferate in response to S100 beta, suggesting that the mitogenic activity of S100 beta is selective for astroglial cells. These results suggest that S100 beta may be involved in the coordinate development and maintenance of the central nervous system by synchronously stimulating the differentiation of neurons and the proliferation of astroglia.
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PMID:Neurotrophic protein S100 beta stimulates glial cell proliferation. 190 67

Antigen expression in a human glioblastoma was investigated by immunochemical methods in the primary tumor, the first and second recurrence, a permanent cell line derived from the first recurrence and in its xenotransplantation tumors. In the primary tumor, GFAP, vimentin, S100, Leu-7 and glioma-associated antigens (GAA) as defined by the monoclonal antibodies (mAbs) MUC 2-39, MUC 8-22 and MUC 2-63 were markedly expressed. In the recurrences, gradual loss of GFAP and Leu-7 could be observed, whereas S100, vimentin and GAA gave similar results to those in the primary tumor. In contrast, fibronectin and collagen IV, which were restricted to the vessel walls in the primary tumor, were represented in sarcomatous areas of the recurrences. In some of these areas, co-expression of glial cell markers was observed. In short-term cell cultures, expression of glia- and glioma-associated antigens as well as fibronectin and collagen IV was comparable to that of the recurrent tumor tissue. In long-term passages, immunoreactivity of GFAP, Leu-7 and S100 decreased, whereas GAA, vimentin and fibronectin increased. Collagen IV positive cells were not visible beyond passage 15. Transplantation tumors were only partly positive for glial cell markers, but revealed strong immunoreactivity for GAA, fibronectin and collagen IV. With these observations we confirm that the phenotypic variability of glioma cells makes it difficult to identify the origin of cells in human glioblastomas from their antigenicity.
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PMID:Antigen variation in a human glioblastoma: from the primary tumor to the second recurrence, permanent cell line and xenotransplantation tumors. 206 11

Retrovirus vectors only integrate into the genome of dividing cells and can thus be used to selectively infect tumor cells in the adult rat brain. Gene delivery was assessed by using the retrovirus BAG vector, which bears the Escherichia coli lacZ gene under the MoMLV LTR promoter-enhancer element, and by histochemical staining for bacterial beta-galactosidase activity. Direct injection of this vector (90-900 cfu) into the adult rat brain, with or without prior inoculation of C6 glioma cells (2 x 10(5) cells) resulted in labeling of only a few cells as assessed 1 week later. When the psi 2-BAG packaging line was grafted into the brain, labeled psi 2-BAG cells could be found after 1 day, but not after 5 days, following grafting, suggesting that the grafted cells had been rejected and that no endogenous cells had integrated released vector, or that expression of lacZ had been turned off. In contrast, when the psi 2-BAG packaging line was grafted into a brain region, which had been inoculated previously with rat C6 glioma cells (2 x 10(5) cells), beta-galactosidase labeling of these tumor cells, identified by immunocytochemistry for glial fibrillary acidic protein and S100, could be demonstrated 10 days later. Thus, grafting of retrovirus packaging lines into adult brain provides a mean to infect tumor cells in situ. The grafted packaging cells may continue to release retrovirus particles for an extended period, thus infecting more cells at the stage of division appropriate for viral integration, as compared to inoculation of the virus alone. Grafting of retrovirus packaging cell lines could be used to selectively deliver "killer" or "suppressor" genes to tumor cells in the brain to curtail their growth.
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PMID:Gene delivery to glioma cells in rat brain by grafting of a retrovirus packaging cell line. 212 47

The synthesis of S100 protein in cultured human melanoma cells was examined using metabolic labeling with [35S]methionine, immunoprecipitation with anti-S100 protein antiserum, and polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Six of seven cell lines derived from melanomas synthesized relatively large amounts of S100 protein, whereas three cell lines derived from normal melanocytes synthesized lesser amounts. Synthesis of S100 protein was not detected in 10 human cell lines of nonneuroectodermal origin. Analysis of poly(A+) RNA from one melanoma cell line by Northern blot hybridization with a probe specific for the beta subunit of rat S100 protein revealed a single mRNA species of 1.0 kb coding for the human protein. Flow cytometric analysis of individual cells of two melanoma cell lines and the rat glioma cell line C6 indicated that G0/G1 cells were heterogeneous with respect to S100 protein expression, while almost all the cells in S + G2 + M expressed S100 protein. These results suggest that expression of S100 protein in G0/G1 could be a prerequisite for progression of the cells through the cell cycle.
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PMID:S100 protein expression in human melanoma cells: comparison of levels of expression among different cell lines and individual cells in different phases of the cell cycle. 229 61

S100 protein is a low molecular weight, EF-hand, Ca2(+)-binding protein widely distributed and conserved in the central nervous system of vertebrates. The gene coding for the beta subunit of human S100 protein (S100 beta) has been recently mapped to chromosome 21. In order to study the expression of this gene in normal and abnormal brain development, we have isolated and characterized overlapping genomic clones spanning the region coding for human S100 beta and its flanking sequences. The intron-exon organization of the human S100 beta gene is similar to that of the genes coding for several other members of the S100 protein subfamily of EF-hand proteins. The human S100 beta gene is composed of 3 exons, the first of which specifies the 5'-untranslated region, while the second and third each encode a single EF-hand, Ca2(+)-binding domain. The promoter region contains several potential regulatory transcription elements including the cAMP-responsive elements CRE and AP-2. A novel sequence motif, the S100 protein element, situated in close proximity to the TATA box of the genes of several members of the S100 protein subfamily, has been identified. In addition, multiple repeats with similar nucleotide sequence and location to the recently reported beta globin direct repeat elements have been also found in the human S100 beta promoter. A full length (17.3 kilobases) copy of the human S100 beta gene was constructed and transfected into rat glioma C6 cells. Stable transfectants were shown to express correctly initiated transcripts of the human S100 beta gene, indicating that the cloned sequences contain functional regulatory transcription elements.
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PMID:Cloning and expression of the human S100 beta gene. 239 38

We have analyzed the levels, subcellular distribution, and target proteins of two calcium-modulated proteins, S100 and calmodulin, in differentiated and undifferentiated rat C6 glioma cells. Undifferentiated and differentiated C6 cells express primarily the S100 beta polypeptide, and the S100 beta levels are four-fold higher in differentiated compared to undifferentiated cells. Double fluorescent labeling studies of undifferentiated cells demonstrated that S100 beta staining localized to a small region of the perinuclear cytoplasm and colocalized with the microtubule organizing center and Golgi apparatus. Analysis of differentiated C6 cells demonstrated that S100 beta distribution and S100 beta-binding protein profile changed significantly upon differentiation. In addition, the brain-specific isozyme of one S100-binding protein, fructose-1,6-bisphosphate aldolase C, can be detected in differentiated but not undifferentiated C6 cells. While changes in the subcellular distribution of calmodulin were not observed during differentiation, calmodulin levels and calmodulin-binding protein profiles did change. Altogether these data suggest that S100 beta and calmodulin regulate different processes in glial cells and that the regulation of the expression, subcellular distribution, and target proteins of S100 beta and calmodulin during differentiation is a complex process which involves multiple mechanisms.
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PMID:Analysis of the calcium-modulated proteins, S100 and calmodulin, and their target proteins during C6 glioma cell differentiation. 291 Aug 76


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