Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.3.5.1 (succinate dehydrogenase)
 8,177 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Increasing use is being made of colorimetric assays to quantitate viable cells, e.g., the cellular reduction of the tetrazolium salt, MTT, to formazan by mitochondrial succinate dehydrogenase. We validated this assay for cell proliferation in mixed lymphocyte cultures as compared with 3H-thymidine uptake, and for inhibition of cell proliferation induced by interferon with results compared by direct cell counting. We also found that cells do not, as previously assumed, require functional mitochondria: there were no differences in formazan production by normal cells or respiratory defective cells in which mitochondria had been poisoned by the nucleic acid toxin, ethidium bromide. The high reproducibility of MTT metabolism by lymphoblasts and various cultured cell lines establishes the reliability and versatility of this method for quantitating cell numbers.
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PMID:Validation of the MTT dye assay for enumeration of cells in proliferative and antiproliferative assays. 141 86

We have in this study used the 3-(4,5-dimethyl-2- thiazoyl) -2,5-diphenyl 2-H-tetrazolium bromide (MTT) end point in our histoculture drug-response assay. We have previously demonstrated that the formazan crystals formed by MTT reduction by mitochondrial succinate dehydrogenase reflect polarized light and can be measured by pixel analysis in intact tissue. The results described here indicate a total specificity of 93.8% and a total accuracy of 74.6% of the MTT end point for drug response in histoculture correlating with nine different human xenograft tumors grown in nude mice with respect to the in vivo drug response data. This in vitro system allows prediction of positive and negative responses to drugs, with a rate of 70% and 71.8%, respectively. The system described here has potential for clinical use because of the possibility of simultaneous description of the MTT values and heterogeneous response to drugs within individual tumors.
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PMID:Correlation of drug response in human tumors histocultured in vitro with an image-analysis MTT end point and in vivo xenografted in nude mice. 144 93

The chemosensitivities of squamous cell carcinoma (SCC) tissues from the head and neck area were compared to findings of adenocarcinoma, mainly from digestive organs. The sensitivity of each tissue was determined using the in vitro succinate dehydrogenase (SD) inhibition test, which shares a common principle with the 3-(4,5-dimethyl-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Tumor tissues were obtained at surgery or biopsy. Anticancer drugs tested were carboquone, Adriamycin, mitomycin C, cisplatin (CDDP), aclacinomycin A, 5-fluorouracil and 1-hexylcarbamoyl-5-fluorouracil with 10 times the peak plasma concentration, respectively. The means +/- standard deviations of SD activities in SCC tissues were significantly lower than those in adenocarcinoma tissues (p less than 0.001), and the sensitivity rates of SD activity in SCC tissues had a higher value than those in adenocarcinoma tissues (p less than 0.05), against each drug. Our study showed that CDDP-based combination regimens might be effective for SCC tissues. The chemosensitivity of each excised tissue should be tested, in order to prescribe sensitive, effective drugs for each patient.
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PMID:Comparison of in vitro anticancer chemosensitivity between human squamous cell carcinoma and adenocarcinoma. 152 69

This study compares the toxic effects of the carotenoids, beta-carotene and canthaxanthin, and alpha-tocopherol (vitamin E) on human tumor cells and their normal counterparts in vitro. Seven different malignant cell lines were examined: oral carcinoma (two cell lines), breast (two cell lines), lung carcinoma (two cell lines), and malignant melanoma. The in vitro cell culture assays showed a consistent morphologic change in the affected tumor cells following treatment with carotenoid or vitamin E. A rounding of the tumor cells and eventual lifting off the tissue culture plate were observed. These changes were apparent after 1 to 5 hours of treatment depending on the tumor cell line. Associated with these observable cellular changes were quantitative reductions in proliferation (3H-thymidine proliferation) and succinic dehydrogenase activity (MTT assay). In addition, there was a noticeable change in protein expression, with an increased expression of a 70-kD protein following treatment with beta-carotene. This protein was associated with tumor cells showing a decrease in proliferation (oral carcinoma, malignant melanoma) but not with normal keratinocytes or melanocytes. These studies substantiate a selective cytotoxic effect on human tumor cell growth by carotenoids and alpha-tocopherol in vitro, and may provide an explanation of the therapeutic activity of these agents and their possible use in the treatment of premalignancy or early oral carcinoma.
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PMID:The selective cytotoxic effect of carotenoids and alpha-tocopherol on human cancer cell lines in vitro. 154 92

The purpose of this study is to assess effects of fibroblasts in the vitro chemosensitivity testing on human lung cancer cells and to remove them. Fourteen lung cancer cell lines and 14 fibroblasts derived from resected specimens of lung cancers were used, whose S.D (succinate dehydrogenase) activities were measured with MTT colorimetric assay. The chemosensitivity of a lung cancer cell alone was compared with that of mixed cancer cell and fibroblast. As results, S.D activities of fibroblasts were less 2-4 fold than those of lung cancer cells. Fibroblasts were as sensitive to CDDP, MMC and 5-FU as lung cancer cells, but more sensitive to ADM and VP-16 than them. When sensitivity testings were performed on mixed cancer cells and fibroblasts, or mixed cancer cells and conditioned media of fibroblasts to CDDP with 3 day's incubation times, the sensitivity was affected in 61%, or 10% of all the pairs, respectively. However, when these tests were done without any incubation times, the sensitivity was not affected. Therefore, it was suggested that anticancer drugs had to be simultaneously added when single cell suspensions were plated if resected specimens were used in a anticancer drug sensitivity test.
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PMID:[A study of fibroblasts in the chemosensitivity testing on human lung cancer cell lines]. 180 80

A major problem associated with the succinate dehydrogenase inhibition (SDI) test using tetrazolium dye (MTT) as a cancer chemosensitivity testing is the contamination of non-malignant cells in the tumour tissues. Highly purified fresh human tumour cells from 44 solid tumours and 24 malignant ascites were used for the MTT assay. The purity of tumour cells was greater than 90% after separation on Ficoll-Hypaque and Percoll discontinuous gradients. The OD570 obtained from tumour cells alone was higher than that from non-malignant cells. The chemosensitivity of tumour cells was distinct from that of non-malignant cells. Moreover, the chemosensitivity of highly purified tumour cells was also distinct from that of non-purified cells just separated from tumour tissues. 31 of the 68 patients had evaluable lesions, and received cancer chemotherapy according to the results of MTT assay using highly purified tumour cells. A clinical response was obtained in 10 of the 31 patients (response rate = 32.3%, 5 complete responses, 5 partial responses).
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PMID:Chemosensitivity testing with highly purified fresh human tumour cells with the MTT colorimetric assay. 183 95

In vitro thermosensitivity of various human tumors including 90 esophageal, 10 gastric and 40 colo-rectal cancers were evaluated using the succinate dehydrogenase inhibition (SDI) test. Tumor fragments minced with scissors were incubated at 43 degrees C as heat treated cells and at 37 degrees C as controls for 20 hrs, and assayed for the succinate dehydrogenase (SD) activity using 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) as a hydrogen acceptor. The thermosensitivity was estimated by the percentage of SD activity of heat treated cells compared to that of each control. A variation in the thermosensitivity was noted between patients. The SD activity was 60.1 +/- 20.3% (mean +/- standard deviation) for esophageal cancers, 34.9 +/- 21.7% for gastric cancers, 50.3 +/- 20.6% for colo-rectal cancers. Significant differences were noted between esophageal cancers and gastric cancers, colo-rectal cancers (p less than 0.01 and p less than 0.05, respectively). When the thermosensitivity was arbitrarily defined as reduction in the SD activity to 50% of control or less, the positive rates were 31.1% for esophageal cancer, 70% for gastric cancer and 62.5% for colo-rectal cancer. Our results show that the SDI test is a useful method for determination of the thermosensitivity of clinical samples.
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PMID:[In vitro thermosensitivity of various human tumors evaluated using the SDI (succinate dehydrogenase inhibition) test]. 223 61

The influence of 19 substances on the reduction of thiazolyl-blue (MTT) by cultivated calf aortic endothelial cells was studied. The substances tested could be classified into three groups. The first one includes drugs without significant effect on the reduction of MTT, the second one inhibits these reaction only weakly (less than 50%) and 10 substances of the third group showed an inhibition rate greater than 50%. There is no statistical reliability in the correlation between the IC50-values of the substances studied in the MTT-test and their LD50-values (mouse, per os). The MTT-test does not permit the estimation of the basal cytotoxicity but only the inhibition of the activity of succinate dehydrogenase and the cytochrome c/c1-complex of the respiration chain of cultivated endothelial cells.
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PMID:[Is the estimation of the activity of MTT-reduction suitable for the determination of basal cytotoxicity?]. 223 95

The chemosensitivity was evaluated by the in vitro succinate dehydrogenase inhibition (SDI) test in 1,000 human tumors including 237 gastric cancers, 116 colorectal cancers, 113 hepatoma and 534 others. These tumor cells were exposed to 5 kinds of antitumor drugs, carboquone (CQ), adriamycin (ADM), mitomycin C (MMC), aclacinomycin A (ACR), cis-platinum (DDP). After exposure to the antitumor drugs, cell viability was assessed with colorimetric assay, based on the ability of succinate dehydrogenase (SD) in living tumor cells to reduced a tetrazolium (MTT) to a formazan. The chemosensitivity was determined to be positive when the SD activity of drug exposed cells decreased to below 50% of that of control cells, on day 3 of exposure. The chemosensitivity varied in the tumor tissues. The chemosensitivity of metastatic lesions of lymph nodes were higher than that of the primary lesions, while metastatic liver tumors had lower sensitivity than the primary lesions. The intra-tumorous distribution of SD activity in 12 human gastric cancers were compared with normal adjacent tissues using histochemistry. Seventy-five % (9/12) of gastric cancer tissues had higher SD activity than normal adjacent tissues. The SDI test is rapid and simple method to predict the sensitivity test of various human tumors to antitumor drugs.
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PMID:[The sensitivity of 1,000 human tumors to antitumor drugs using the succinate dehydrogenase inhibition (SDI) test]. 227 70

The succinate dehydrogenase inhibition (SDI) test was used for determining chemosensitivity of various human tumors. This test was based on the correlation between the cellular succinate dehydrogenase activity as determined by 3-(4,5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT), and cell viability. The chemosensitivity varied in the tissue. Some factors are involved in the chemosensitivity, that is origin of a tumor, tissue differentiation and tissue DNA synthetic activity. This test is a convenient method for clinical use and provides important information about chemosensitivity.
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PMID:[In vitro chemosensitivity test: succinate dehydrogenase inhibition (SDI) test]. 230 18


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