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)

The transport of the amino acid amide N-[3H]sarcosinamide (methyl glycinamide) was investigated in human glioma SK-MG-1 cells. Sarcosinamide uptake was found to be temperature dependent, sodium independent, and linear up to 1 min at 22 degrees C. Equilibrium was reached after 10 min at 22 degrees C with accumulation slightly above unity. Sarcosinamide was not metabolized in the cells as shown by thin layer chromatography. The uptake of sarcosinamide was significantly decreased when the extracellular pH was lowered from 7.5 to 6.0 and significantly enhanced at pH values above 7.5. The latter effect may be due mainly to increased cell permeability at high pH. The uptake of the labeled sarcosinamide was trans-stimulated by excess cold sarcosinamide. Sarcosinamide uptake over a 200-fold range of concentrations followed Michaelis-Menten kinetics with a Km of 0.284 +/- 0.041 mM and a Vmax of 0.154 +/- 0.024 nmol/10(6) cells/min. The uptake of sarcosinamide was significantly reduced by iodoacetate but not by the metabolic poisons NaF, ouabain, or dinitrophenyl, suggesting that the uptake is not dependent on energy, rather it proceeds by facilitated diffusion. Several naturally occurring substrates were unable to inhibit the uptake of sarcosinamide. Leucine significantly reduced the uptake of sarcosinamide, while sarcosinamide was a weak inhibitor of leucine transport. 2-Aminobicyclo[2,2,1]heptane-2-carboxylic acid a specific substrate for the sodium-independent, 2-aminobicyclo[2,2,1]heptane-2-carboxylic acid-sensitive amino acid system L failed to inhibit the uptake of sarcosinamide. Epinephrine reduced the uptake of sarcosinamide and sarcosinamide was equally potent as an inhibitor of epinephrine transport. Dixon plot analysis demonstrated that epinephrine (Km = 0.270 mM) inhibits the uptake of sarcosinamide competitively (Ki = 0.260 mM). These results indicate that sarcosinamide is a substrate for the catecholamine transporter. The alkylating agent, sarcosinamide chloroethylnitrosourea, was tested for its ability to inhibit the uptake of sarcosinamide. The results of Dixon plot analysis were consistent with competitive inhibition of sarcosinamide uptake and the inhibition constant Ki for SarCNU was found to be 3.26 +/- 0.57 mM. The steady-state intracellular concentration of SarCNU was found to be significantly higher (cell:medium ratio of 1.03 +/- 0.01) than that of BCNU cell:medium ratio of 0.52 +/- 0.12). These findings indicate that SarCNU and sarcosinamide share the same carrier for uptake in SK-MG-1 cells. This transport mechanism may be responsible for the increased accumulation of SarCNU as compared to BCNU, a nitrosourea which enters cells by passive diffusion.
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PMID:Transport of amino acid amide sarcosinamide and sarcosinamide chloroethylnitrosourea in human glioma SK-MG-1 cells. 169 54

Tumor-infiltrating lymphocytes (TIL) were generated from 10 glioma specimens by using recombinant interleukin-2 and an anti-CD3 antibody (CD3 + TILs). We obtained more than 1 x 10(9) cells in 5 cases, more than 5 x 10(8) cells in 2 cases, and about 1 x 10(8) cells in 3 cases during three weeks of incubation from small specimens ranging in weight from 0.5 to 2.0 g. In 4 cases, TILs were expanded following stimulation with only rIL-2 (CD3-TILs). The growth rate of CD3-TILs was less than that of CD3 + TILs. Cytotoxicity of CD3 + TILs was lower than that of lymphokine-activated killer (LAK) cells in a standard 4h 51Cr release assay. Cold target inhibition was undertaken in three cases and specific cytotoxicity could be shown in only one case. CD3 + TILs mainly consisted of CD3-positive cells, ranging from 63.2 to 99.9%. The ratio of CD4-positive cells to CD8-positive cells was not constant. The expression of Leu 7 and CD16 was low. The present study did not confirm previous findings that TILs were more tumor-selective and potent than LAK cells. Furthermore, the results on in vitro antitumor activity of those cells were not necessarily consistent with the results on their clinical activity. Further careful work is necessary on the preparation of immunocytes and the subsequent adoptive immunotherapy.
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PMID:Cytological characteristics of human glioma-infiltrating lymphocytes stimulated with recombinant interleukin 2 and an anti-CD3 antibody. 182 92

In order to examine a role of extracellular matrix (ECM) components in the process of glioma cell invasion, we investigated the immunohistochemical localization of fibronectin (FN), laminin(LN) and FN-receptor (FN-R) in human malignant gliomas. The surgical specimens were obtained from 15 patients with malignant gliomas. Tumor tissue and adjacent brain tissue including tumor infiltration were frozen at -80 degree C immediately after the resection. Ten microns thick frozen tissue was cut out on a cryostat and divided into three different parts on the histology stained with HE, ie, the tumor region(T), brain tissues with tumor infiltration(I), and the border region between these two parts(B). These sections were air-dried, and fixed with cold acetone (-4 degrees C) for 5min. Adjacent sections were immunohistochemically stained by ABC method, using monoclonal antibody for FN-R and polyclonal antibodies for FN and LN. FN, LN and FN-R were all stained at the vascular and pial-glial basement membranes intensely in all gliomas. In immunostain for FN, fine networks of FN were observed in the extracellular space in all three parts. Some tumor cells were clustered around such networks of FN in brain tissues with tumor infiltration. Immunostain for LN demonstrated that the vascularity in the border between the tumor and the brain with tumor infiltration was much higher than that in other parts. LN was not stained in the extracellular space in all these gliomas. FN-R was expressed in some tumor cells, especially in the clustered tumor cells in the brain with tumor infiltration.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Immunohistochemical localization of fibronectin, laminin and fibronectin-receptor in human malignant gliomas--in relation to tumor invasion]. 182 88

Preparing cellular structures for visualization by high-resolution scanning electron microscopy (SEM) is a multi-step process which includes fixation, dehydration, drying and metal coating. Drying and metal coating are limiting for high-resolution work. Commonly, the dried samples are exposed to the air before they are inserted into a metal coating apparatus, thereby exposing them to moisture and the accompanying risk of rehydration, which may cause changes in the supramolecular structure. We have modified a freeze-dryer to accommodate a magnetron sputtering head, in order to sputter-coat the frozen-dried samples while still in the drying chamber in the cold, a process we call cryosputtering. A layer of 1.5 nm of tungsten was cryosputtered onto whole mounts of cytoskeletons from detergent-extracted human glioma cells or fibroblasts and the specimens were examined by high-resolution SEM and transmission electron microscopy (TEM). To reduce the effects of backstreaming oil from the vacuum system, a turbomolecular pump backed by a two-stage rotary vane pump was connected to the drying-coating chamber. This pump system provides a high vacuum, making it possible to dry the specimens at -90 degrees C/183 K, thus reducing the risk for recrystallization of water. Furthermore, the high vacuum minimizes the negative effects of contaminants, which can be deposited onto the specimen surface and affect the quality of the metal coat formed during sputtering.
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PMID:Cryosputtering--a combined freeze-drying and sputtering method for high-resolution electron microscopy. 203 32

Indirect immunofluorescence was used to determine the distribution of Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) in rat embryo fibroblast 3Y1 cells, rat C6 glioma cells, and human epidermoid carcinoma KB cells. During interphase at growing phase, CaM kinase II was localized diffusely in the cytoplasm and in the nucleus. In the nucleus, the enzyme was localized within the whole nuclear matrix in which the enzyme was specially concentrated in nucleoli. During mitosis, CaM kinase II was found to be a dynamic component of the mitotic apparatus, particularly present at microtubule-organizing centers. In metaphase and anaphase, CaM kinase II was observed at centrosomes and between the spindle poles. During telophase, CaM kinase II was condensed as a bright fluorescent dot at the midzone of the intercellular bridge between two daughter cells, while tubulin was found at each side of the midbody. Colchicine, a microtubule inhibitor, disorganized the tubulin- and CaM kinase II specific fluorescent structure of mitotic 3Y1 cells. In cold-treated cells, CaM kinase II was localized predominantly at centrosomes. The localization of CaM kinase II in the cell nucleus and the mitotic apparatus suggests that the enzyme may play a role in the cell cycle progression of mammalian cells.
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PMID:Ca2+/calmodulin-dependent protein kinase II: localization in the interphase nucleus and the mitotic apparatus of mammalian cells. 216 78

The distribution of three high molecular weight proteins, MAP-1 (Mr 330 000), MAP-2 (Mr 300 000) and plectin (Mr 300 000) in various fractions obtained in cycles of temperature-dependent polymerization/depolymerization of microtubules from rat glioma C6 cells was studied. Using gel electrophoresis and immunoautoradiography/immunoblotting all three proteins were found to codistribute only partially with tubulin because considerable parts remained in the cold-insoluble fractions. Moreover, the proteins, particularly MAPs, were proteolytically degraded during cycling. By contrast, when microtubules were polymerized with taxol after isotonic cell lysis a considerable enrichment of MAP-1 and MAP-2 was achieved; again, plectin co-distributed only partially. In this procedure too, MAPs, especially MAP-2, were found to be highly subject to proteolysis, unless free Ca2+-ions were rigorously avoided. Proteolytic fragments generated from MAP-2 were of similar size independent of whether temperature- or taxol-dependent polymerization procedures were used, suggesting the occurrence of a MAP-2-specific protease. When the spatial arrangement of the high Mr proteins on taxol-polymerized C6 cell microtubules was directly visualized using gold-immunoelectron microscopy, a periodical, apparently helical, decoration of microtubules was found for MAP-1 and MAP-2; plectin was irregularly arrayed. A predominantly helical arrangement of both MAPs was demonstrated also for microtubules reconstituted from mammalian brain.
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PMID:Identification and spatial arrangement of high molecular weight proteins (Mr 300 000-330 000) co-assembling with microtubules from a cultured cell line (rat glioma C6). 286 45

We have cultured peripheral blood lymphocytes (PBL) from glioblastoma patients in recombinant interleukin-2 (IL-2) containing medium for a period of 5 days. The cytotoxicity of these cells was tested on 51Cr-labelled autologous dissociated glioblastoma cells which had not been cultured. Significant cytotoxicity against glioma cells was observed in seven out of nine cases. IL-2 activated PBL from normal donors were equally cytotoxic against these glioma cells. Autologous lymphocytes activated by phytohaemagglutinin were also lysed in most cases, and the erythroleukemia cell line K562 was highly susceptible to the cytotoxic capability of the IL-2 activated PBL. In cold target inhibition experiments, K562 inhibited the cytotoxicity against both autologous and allogenic glioma cells, and glioma cells inhibited the cytotoxicity against K562. Following immunomagnetic separation, the IL-2 activated cells demonstrated cytotoxicity against glioma cells, K562 cells, and PHA blasts in both the CD8+ and the CD8- subsets.
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PMID:Human interleukin-2 activated cytotoxic cells kill autologous glioma cells in vitro. 326 Sep 42

Utilizing a treatment concept geared to the cell cycle of the glioma, a CT determined tumor volume and boundaries, 125I dosimetry data and a reference probe template system, it is now feasible to produce a volume implant of an intracranial mass based on prospective planning with accurate postimplant correspondence. The cell cycle oriented treatment plan is felt perhaps to be more beneficial in the treatment of the highly malignant glioblastoma, considering its wide range of cell cycle times, large irregular volumes and large dormant segment, than would be a similar isotope source delivering a high-dose rate, but short-term course irradiation. Seeds are contained within Lexan tubes, thereby allowing accurate assessment of postoperative dosimetry planning, negating seed migration and possible 'cold spots' within a volume implant as would be noted with unrestrained seeds. The implant described in this communication is designed to remain in place for approximately 20 months, a period of time well beyond the life expectancy of any group of failed glioma patients. Although ultimately the system may prove most beneficial in newly diagnosed glioblastomas, the current trial in patients having previously undergone 5-6000 rads of external beam therapy is not considered hazardous to surrounding brain.
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PMID:On a method of dosimetry planning and implantation of 125I for interstitial irradiation of malignant gliomas. 378 8

Malignant tumors retain hematoporphyrin to a much greater extent than do normal tissues and can be destroyed by exposure to light. To utilize this mechanism in the treatment of malignant brain tumor, we investigated the antitumor effect of photoradiation on rat and mouse glioma, utilizing hematoporphyrin administration and cold light irradiation. In vitro study of rat glioma (EA285), the tumor cells which were exposed to hematoporphyrin and light irradiation showed marked degeneration in a short time, though no change was found in the control groups of hematoporphyrin administration alone and of light irradiation alone. The subcutaneously transplanted gliomas of rat and mouse also showed the growth inhibition after treatment of hematoporphyrin and light irradiation, though they grew up again. Histological degeneration by this treatment reached about 7 mm depth in the tumor. It was made clear that the effect on gliomas was induced by photosensitization and not by heat. From these results it is concluded that photoradiation therapy would be a great means for adjuvant therapy for malignant brain tumor.
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PMID:[Photoradiation therapy of experimental brain tumor]. 406 17

The subunit structure of islet-activating protein (IAP), pertussis toxin, has been analyzed to study a possibility that this protein is one of the A-B toxins [Gill, D. M. (1978) in Bacterial Toxins and Cell Membranes (Jeljaszewicz, J., & Wadstrom, T., Eds.) pp 291-332, Academic Press, New York]. Heating IAP with 1% sodium dodecyl sulfate caused its dissociation into five dissimilar subunits named S-1 (with a molecular weight of 28 000), S-2 (23 000), S-3 (22 000), S-4 (11 700), and S-5 (9300), as revealed by polyacrylamide gel electrophoresis; their molar ratio in the native IAP was 1:1:1:2:1. The molecular weight of IAP estimated by equilibrium ultracentrifugation was 117 000 which was not at variance with the value obtained by summing up molecular weights of the constituent subunits. The preparative separation of these IAP subunits was next undertaken; exposure of IAP to 5 M ice-cold urea for 4 days followed by column chromatography with carboxymethyl-Sepharose caused sharp separation of S-1 and S-5, leaving the other subunits as two dimers. These dimers were then dissociated into their constituent subunits, i.e., S-2 and S-4 for one dimer and S-3 and S-4 for the other, after 16-h exposure to 8 M urea; these subunits were obtained individually upon further chromatography on a diethylaminoethyl-Sepharose column. Subunits other than S-1 were adsorbed as a pentamer by a column using haptoglobin as an affinity adsorbent. The same pentamer was obtained by adding S-5 to the mixture of two dimers. Neither this pentamer nor other oligomers (or protomers) exhibited biological activity in vivo. Recombination of S-1 with the pentamer at the 1:1 molar ratio yielded a hexamer which was identical with the native IAP in electrophoretic mobility and biological activity to enhance glucose-induced insulin secretion when injected into rats. In the broken-cell preparation, S-1 was biologically as effective as the native IAP; both catalyzed ADP-ribosylation of a protein in membrane preparations from rat C6 glioma cells. In conclusion, IAP is an oligomeric protein consisting of an A (active) protomer (the biggest subunit) and a B (binding) oligomer which is produced by connecting two dimers by the smallest subunit in a noncovalent manner. Rationale for this terminology is discussed based on the A-B model.
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PMID:Subunit structure of islet-activating protein, pertussis toxin, in conformity with the A-B model. 629 44


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