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)

This study was undertaken to evaluate the colorimetric MTT [3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide] assay as a means of testing the sensitivity of gliomas to chemotherapeutic agents in vitro. Eight human glioma established cell lines were plated in 96-well tissue culture plates and incubated for 4 days with 10 different anti-cancer agents; 5 different concentrations of each drug were tested. The MTT dye was then added to the wells, and the resulting formazan precipitate was solubilized with dimethylsulfoxide (DMSO). The spectrophotometric absorbance (measured at 570 nm) of control and experimental wells was used to calculate the cytotoxicity index (CI). Values with a CI greater than 50% growth inhibition indicated cytotoxic efficacy (sensitivity to the chemotherapeutic drug). Six of the seven (85.7%) glioma cell lines were highly sensitive at varying concentrations to mitomycin C, cisplatin, and doxorubicin. Four of the seven (57.1%) cell lines demonstrated intermediate sensitivity to mitoxantrone and vinblastine. Five of the seven (71.4%) cell lines exhibited resistance to etoposide, bleomycin, cosmegen, and BCNU. One of the cell lines tested, U-138MG, failed to produce the MTT formazan precipitate, so that the sensitivity of this cell line to the panel chemotherapeutic drugs could not be determined. The variability of the results indicates the need for an in vitro screening method to evaluate the effectiveness of clinical and experimental chemotherapeutic agents. The MTT assay provides a rapid method of screening antineoplastic agents against gliomas for cytotoxicity.
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PMID:Test for chemotherapeutic sensitivity of cerebral gliomas: use of colorimetric MTT assay. 812 70

Biological effects of human natural tumor necrosis factor-alpha (TNF) on glioblastoma cells in vitro and on glioma patients were investigated. TNF treatment on glioblastoma cells, even at a high dose (256 U/ml), exhibited no remarkable cytocidal activity in MTT assay, but at lower doses significantly inhibited colony forming and DNA synthesis. TNF at a low dose (10 U/ml) stimulated production of prostaglandin E2, Mn-superoxide dismutase, interleukin (IL)-6 and IL-8 by glioblastoma cells. These results indicated that the direct effect of TNF on human glioblastoma cells is rather antiproliferative than cytotoxic and is to modulate their metabolic pathways. In an early Phase I clinical trial, TNF was administered intracranially to six patients bearing glioblastoma. In this trial, the author studied in vivo immunological responses in the cerebrospinal fluid and regional fluid after the regional TNF injections. TNF in these body fluids were detected with a half life of several hours. There occurred a substantial number of leukocyte migration after the TNF administration. Neutrophils appeared first peaking at 8 to 12 hours, and then CD4+CD8-T cells and CD11b+CD13+CD14+ monocytes followed. IL-8 activity in the cerebrospinal fluid simultaneously corresponded to peak of the neutrophil migration. Increases in IL-6, IL-1 beta and prostaglandin E2 levels in the cerebrospinal fluid, regional fluid or both occurred peaking at 8 to 12 hours after TNA infection. Neither IL-2 nor interferons was detected. In conclusion, TNF may act as an antineoplastic agent by its direct cytostatic effects and indirectly through immune modulatory effects.
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PMID:[In vitro and in vivo immunobiological responses of glioblastoma to human natural tumor necrosis factor-alpha]. 142 94

Physalin F and physalin D were isolated and characterized from the ethanolic extract of the whole plant of Physalis angulata L. (Solanaceae). Systematic fractionation of the ethanolic extract of the plant led to characterization of physalin F from the fraction PAIV-2 as an active ingredient which showed cytotoxicity in vitro by DEA and MTT assays on 8 cancer cell lines, five human cancer cell lines: HA22T(hepatoma), HeLa(cervix uteri), KB(nasopharynx), Colo-205(colon) and Calu-1(lung); and three animal cancer cell lines: H1477(melanoma), Hep-2(laryngeal) and 8401(glioma). It was found that the anti-hepatoma action is the strongest, and the anti-HeLa is the next. Physalin F also had an antitumor effect in vivo against P388 lymphocytic leukemia in mice whereas physalin D was inactive both in vitro and in vivo.
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PMID:Antitumor agent, physalin F from Physalis angulata L. 162 43

beta-Sitosterol (SI-0), beta-sitosterol glucoside (SI-1), dioscin (SI-2), methyl protoprosapogenin A of dioscin (SI-3), methyl protodioscin (SI-4) and protodioscin (SI-5) were isolated and characterized from the whole plant of Solanum indicum L. (Solanaceae). Except for beta-sitosterol, these compounds have not been previously isolated from Solanum indicum L. Both CHCl3 soluble (SI-IV) and insoluble (SI-V) fractions of the ethanolic extract (SI-I) showed cytotoxicity on seven cancer cell lines: Colo-205 (colon), KB (nasopharynx), HeLa (uterine cervix), HA22T (hepatoma), Hep-2 (laryngeal epidermoid), GBM8401/TSGH (glioma) and H1477 (melanoma). The purified constituents, SI-2 and SI-4 showed more potent effects by DEA and MTT assay. SI-2,3,4 and 5 also demonstrated cytotoxicity on cultured C6 glioma cells by PRE assay, ans SI-3,4 and 5 showed a tumor inhibitory effect in vivo in C6 glioma cells. In addition, SI-2 had an inhibitory effect on the DNA synthesis of C6 glioma cells at 10 micrograms/ml.
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PMID:Experimental antitumor agents from Solanum indicum L. 176 63

Chemosensitivity assays including colony forming assay (CFA), MTT dye reduction assay (MTT assay) and thymidine incorporation assay (TIA) for cultured rat and human glioma cells were conducted to determine the correlation among them and the in vivo antitumor efficacy of anticancer drugs using rats implanted glioma cells. Cytotoxicity of various agents such as ACNU, ACR, CDDP, VCR or BLM, was estimated from the concentrations which caused 50% inhibition of the cell growth at the peak plasma concentration. The survival time of tumor bearing rats was assessed after ip treatment with these agents at their estimated clinical doses. This parameter was greater in the drugs that were shown to be highly sensitive in CFA and was consistent with the data for CFA. In the chemosensitivity assays, CFA closely correlated to MTT assay for all agents except VCR, but poorly so to TIA. The results in this study indicate that MTT assay seemed to be useful for determining the chemosensitivity of anticancer drugs and that chemosensitivity assay should be conducted depending on the nature of anticancer drug.
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PMID:[Chemosensitivity assays for malignant gliomas]. 224 Nov 89

Some reports have demonstrated that selenium can inhibit tumorigenesis in some tissues of animal. However, little is known about the inhibitory effect on malignant tumor cells of brain. The purpose of our study was to determine the biological effect of selenium on growth of rat glioma and human glioblastoma cell lines. Cell lines C6 and A172 were obtained from Japanese Cancer Research Resources Bank, Tokyo, Japan (JCRB). Cells were cultured in Dulbecco's Modified Eagle's Medium (DMEM) supplemented with 10% fetal calf serum at 37 degrees C in a humidified atmosphere of air and 5% CO2. Antiproliferative effects of selenium were evaluated using growth rate assay quantifying cell number by MTT assay. An antiproliferative effect of selenium was found in two cell lines, which was more effective on human A172 glioblastoma and less effective on rat C6 glioma.
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PMID:Effect of selenium on malignant tumor cells of brain. 757 18

Recently, it has been reported that CDDP modifies the immune responses of tumor bearing hosts, but problem of the most appropriate treatment with CDDP to augment the host immunity remains unresolved. The purpose of this study was to determine the most advantageous administration of CDDP to increase both its cytotoxic effect and antitumor immune reactivity. Cell growth inhibition in vitro was assessed by MTT assay after treatment of U-251MG cells with various concentrations of CDDP for 24 or 120 hours. The results of this experiment showed that the growth of U-251MG cells in vitro was suppressed by CDDP in a dose-dependent as well as a time-dependent manner. Ten days after subcutaneous inoculation of human glioma cells, GL-9, in the rear flank of nude mice, they were assessed for growth suppression by CDDP. Totally, 20 ml/kg of CDDP was administered to each mouse; in one group (high-dose CDDP group), 5 ml/kg of CDDP on every fifth day, and in the other group (low-dose CDDP group), 2 ml/kg on every day. Measurement of the tumor volume in each group revealed no significant difference between the two groups in terms of the efficacy of tumor growth suppression. Twenty-one days after inoculation, we measured the splenic natural killer(NK) cell activity in each mouse. The results showed that NK cell activity was significantly increased in the low-dose cisplatin (2 ml/kg) group, and significantly decreased in the high-dose cisplatin (10 mg/ml) group, as compared to the control group. The results of our study suggest that the separate administration of low-dose CDDP is a useful treatment strategy for malignant glioma, because it increases the antitumor immune reactivity of hosts without decreasing the direct tumor cytotoxicity of CDDP.
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PMID:[Effects of separate administration of low-dose CDDP on antitumor immune reactivity for treatment of malignant glioma]. 766 72

To assess the interaction of carboplatin and hyperthermia in vitro, the thermochemosensitivities of three glioma cell lines, C6 rat glioma cell line, human glioma cell lines T98G and KMG4, were examined by 3-(4,5-dimethylthiazol-2-yl) -2,5 diphenyltetrazolium bromide (MTT) assay. The cell survival of each cell line decreased according to increasing CBDCA concentration and temperature. With a certain CBDCA concentration, the cell survival at following temperature was significantly decreased from that at 37 degrees: 43 degrees C and 44 degrees C for C6 cells (2.5 micrograms/ml); 41 degrees C, 42 degrees C, 43 degrees C and 44 degrees C for C6 cells (128 micrograms/ml); 42 degrees C, 43 degrees C and 44 degrees C for KMG4 cells (8 micrograms/ml) (CBDCA concentration within parentheses). It is generally considered that the highest tolerable temperature of normal brain is 42 degrees C for 60 minutes, while under 43 degrees C, there is a possibility that a sufficient tumoricidal effect might not be obtained. This study revealed enhanced cytotoxicity of CBDCA with hyperthermia at the temperature lower than 42 degrees C and suggests the possibility to gain increased tumoricidal effect without injuring normal brain by hyperthermia at the normal-tissue-tolerant temperature with systemic administration of relatively lower dose of CBDCA.
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PMID:[Synergistic effect of carboplatin and hyperthermia in rat and human glioma cell lines]. 781 71

Activity of the DNA repair protein O6-alkylguanine-DNA alkyltransferase (AGT) is an important determinant of responsiveness of tumor cells to chloroethylnitrosoureas (CENUs), representative chemotherapeutic agents for primary malignant gliomas. In order to assess the real states of this repair protein in human malignant gliomas, we assayed AGT activity in surgically extirpated 42 malignant glioma samples and studied the distribution of the activity under certain clinical conditions. There were wide variations in AGT activity between individuals. No significant difference in AGT activity on average was seen either between glioblastoma and anaplastic astrocytoma, nor between primary and recurrent tumors. Among 42 malignant gliomas, 7 samples (16.7%) had low AGT activity less than 0.1 pmoles/mg protein. In the case of glioblastoma, tumors possessing higher AGT activity tended to be less responsive to post-operation remission-induction therapy including CENUs. The result of the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) chemosensitivity assay by using the corresponding surgical specimens suggested a close relationship between cellular resistance to CENUs and AGT activity. It was found to be unlikely that a short term administration of CENUs had a significant effect on AGT activity of brain tumors in human body. We could detect a bit of definite evidences of the relevance of AGT to resistance to CENUs and need to conduct further investigations for other resistance factors.
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PMID:O6-alkylguanine-DNA alkyltransferase activity of human malignant glioma and its clinical implications. 786 Nov 89

The monoclonal antibody Ki-67 recognizes a nuclear antigen expressed in the G1, S, G2, and M phase of the cell cycle and has been used extensively as an indicator of cellular proliferation in malignant gliomas, both in the laboratory and clinically. Recently, protein kinase C (PKC) inhibitors have been demonstrated to inhibit malignant glioma growth both in in vitro and in vivo. This study was undertaken to determine whether Ki-67 could function as an indicator of cellular proliferation rate after PKC inhibition in gliomas and to explore cell cycle specificity of such inhibition. Both established and low-passage malignant glioma cell lines have previously been shown to be sensitive to growth inhibition by the PKC inhibitors staurosporine and tamoxifen in vitro (IC50 in the nanomolar and micromolar ranges, respectively), as measured by cell numbers, [3H]thymidine uptake, and flow-cytometric DNA analysis. However, in the same cells that are inhibited by staurosporine and tamoxifen on these assays, and on the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl tetrazolium bromide (MTT) assay in the present study, the Ki-67 labeling index paradoxically increased in a dose-related manner with the same treatments, as measured by immunohistochemistry and confirmed by flow cytometry. For example, in established line U-87, a 20.5% decrease in thymidine uptake and a 28.5% decrease in absorbance on the MTT assay produced by tamoxifen at 1 microM was associated with an increase in Ki-67 labeling from 42% to 62%; staurosporine, which produces a 78.8% decrease in thymidine uptake in cell line A-172 at 10 nM, produced an increase in Ki-67 labeling from 19% to 32%. In this regard, Ki-67 labeling of glioblastoma tissue from a patient treated with high-dose tamoxifen yielded results within the range of 10% to 15% (consistent with values seen in untreated glioblastoma), despite tumor regression with treatment. The authors' interpretation of these results is that these PKC inhibitors are halting the cell cycle in the G1 phase or the G1-S transition (beyond G0 but before S-phase), resulting in a paradoxical increase in labeling while arresting growth. Two important implications from these observations are that Ki-67 is not a reliable indicator of cellular proliferation after treatment with PKC inhibitors and that these inhibitors used at the doses given above halt cell growth in a phase-specific manner.
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PMID:Paradoxical elevation of Ki-67 labeling with protein kinase inhibition in malignant gliomas. 786 Dec 25


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