Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024623 (gastric cancer)
 36,219 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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 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 sensitivity to 5-fluorouracil (5-FU) was examined in 40 well differentiated and 50 poorly differentiated gastric cancer tissues and 15 normal tissues, using the in vitro succinate dehydrogenase inhibition (SDI) test. The tissue phosphorylating and degrading activities of 5-FU were compared in each type of tumor and in the normal tissues. Decreases in succinate dehydrogenase (SD) activity were more apparent in the poorly differentiated cancer tissues than in the well differentiated cancer tissues (p less than 0.005), and than in the normal tissues (p less than 0.001), exposed to 5-FU. The rate of sensitivity to 5-FU was higher in the poorly differentiated than in the well differentiated tissues and than in the normal tissues. The phosphorylating activities of 5-FU, in pathways involving uridine (Urd) phosphorylase and Urd Kinase, and thymidine (dThd) phosphorylase and dThd Kinase, were 1.7 fold higher in the poorly differentiated than in the well differentiated tissues and several fold higher than in the normal tissues (p less than 0.05-p less than 0.001). The degrading activity of 5-FU was similar in both types of tumor and in the normal tissues. Our findings show that 5-FU is actively metabolized to 5-FU-nucleotides in poorly differentiated tissues after incorporation into the tumor cells. 5-FU seems to have an increased susceptibility in cases of poorly differentiated gastric carcinoma.
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PMID:5-Fluorouracil is converted to F-nucleotides more extensively and is more cytotoxic in poorly differentiated than in well differentiated human gastric carcinoma. 238 81

Twenty lines of human gastro intestinal and breast cancer xenografts, in which chemosensitivity spectra by the in vivo nude mouse assay had been clarified. were subjected to the in vitro SDI (succinate dehydrogenase inhibition) assay using MTT dye to assess the accuracy of this drug sensitivity test against 4 drugs i.e., mitomycin C (MMC), adriamycin (ADM) 5 fluorouracil (5-FU), and cisplatin (CDDP). After 3 days incubation, the suspension of every tumor cells including small fragments showed a marked decrease of SD activity even when no anticancer drug was added to the assay medium. Among these 4 drugs evaluated MMC exhibited a statistically significant correlation between chemosensitivity values of the in vitro SDI assay and those of the nude mouse assay. However, the other 3 drugs demonstrated no correlation between the values of these two methods. Since the primary cultured fibroblasts revealed, in general, lower sensitivity to these drugs, contamination of fibroblast may decrease the SDI values when materials from solid tumors with rich stroma such as a type of stomach cancer were subjected. It is considered that the prediction of chemosensitivity to every drug will be impossible by a in vitro SDI assay.
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PMID:[Evaluation of predictability of in vitro SDI assay in comparison with in vivo nude mouse assay]. 280 37

The chemosensitivities of 41 poorly differentiated gastric cancer tissues were compared with that of 16 well differentiated tissues, using the in vitro succinate dehydrogenase inhibition test. These human tissues obtained at the time of surgery were exposed to six different antitumor drugs: carboquone (CQ), adriamycin (ADM), mitomycin C (MMC), aclacinomycin A (ACR), cisplatin (DDP) and 5-fluorouracil (5-FU). The chemosensitivity was determined as positive when the succinate dehydrogenase (SD) activity of the drug exposed cells was decreased to below 50% of that of control cells, on day 3 of exposure. Decrease in SD activity was remarkable in the poorly differentiated tissues, compared to the well differentiated tissues, exposed to ADM, MMC, DDP and 5-FU. The sensitive rates were higher in the poorly differentiated tissues than in the well differentiated tissues, against all six antitumor drugs. Sixty-three per cent of the poorly differentiated tissues were sensitive to more than three antitumor drugs, in an identical tissue, but the rate was only 19% in the well differentiated tissues. The resistant rates to all drugs tested were 20% in the poorly differentiated and 31% in the well differentiated tissues. This would indicate that patients with a poorly differentiated gastric cancer will probably show a better response to antitumor drugs, compared to those with a well differentiated type.
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PMID:Poorly differentiated human gastric carcinoma is more sensitive to antitumor drugs than is well differentiated carcinoma. 303 3

An in vitro chemosensitivity test, the succinate dehydrogenase inhibition (SDI) test, was used to examine 16 pairs of samples obtained simultaneously from primary and metastatic lesions of clinical gastric cancer. Concerning the metastases, 11 were in the lymph nodes and five in the liver. The chemosensitivities of metastatic lesions against six anti-tumour drugs, carboquone (CQ), adriamycin (ADM), mitomycin C (MMC), aclacinomycin A (ACR), and 5-fluorouracil (5-FU), differed from those in the primary lesions, and there were no correlations of chemosensitivities between the primary and the metastatic lesions against these drugs, except for DDP. The lymph nodes were more sensitive to CQ, ADM, MMC, DDP, ACR and 5-FU, while the liver was less sensitive than the primary lesions to CQ, ADM, MMC, DDP, and ACR. Our findings indicate that in patients with lymph node metastasis, there is a sensitivity to anti-tumour drugs, while in cases of liver metastasis, drug treatment may be less effective. We propose that chemosensitivity testing should be done when attempting to design anti-tumour drugs.
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PMID:Chemosensitivity differences between primary and metastatic lesions of clinical gastric cancer. 319 5

In vitro chemosensitivity was evaluated by SDI test in various human tumors including 1 lymph node metastasis of esophageal cancer, 10 gastric cancers, 4 colo-rectal cancers, 1 hepatoma, 2 lung cancers, 2 breast cancers and 1 gallbladder cancer. Tumor fragments cut with scissors were exposed to twelve kinds of antitumor drugs at five to ten times peak plasma concentration. After 3 days at 37 degrees C, each tumor fragment suspension was washed with phosphate-buffered saline and assayed for succinate dehydrogenase (SD) activity using 3-(4,5- dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) as a hydrogen acceptor. When the SD activity of the drug-treated cells was reduced to below 50% that of control cells, the chemosensitivity to the antitumor drug was considered positive. The chemosensitivity of each tumor varied individually. Mitomycin C or 5-fluorouracil are regularly used to treat gastric cancer patients, but, some specimens of gastric cancer in this study showed a resistance to these drugs and an unexpected sensitivity to other drugs. Our results show that the SDI test is a convenient method for clinical use and gives significant information about drug sensitivity.
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PMID:[In vitro chemosensitivity of various human tumors evaluated by the SDI (succinate dehydrogenase inhibition) test]. 405 18

Class pi-glutathione S-transferase (GSTP-1) is one of several factors proposed to affect drug sensitivity to cisdiamminedichloroplatinum (II) (CDDP). It has also been investigated as a potential marker for the serodiagnosis of various types of cancers. In this study, attempts were made to quantify mRNA levels of the enzyme in healthy and cancerous gastric mucosa specimens, and to evaluate their significance in inherent drug resistance to CDDP. Thirty gastric cancer specimens were analysed by northern blotting with radiolabelled GSTP1 cDNA. Of these, the chemosensitivities of 22 specimens were evaluated by the succinic dehydrogenase inhibition (SDI) test. GSTP-1 mRNA was detected in all the specimens, with slightly increased, but non-significant expression in the neoplasms. Comparison of these drug sensitivities with results of northern blotting analysis showed no inverse correlation, as was expected from the widely investigated role of the enzyme in drug resistance.
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PMID:Expression of pi-glutathione S-transferase gene (GSTP1) in gastric cancer: lack of correlation with resistance against cis-diamminedichloroplatinum (II). 785 16

Glutathione-S-transferase (GST) in one of several factors that are proposed to affect tumor sensitivity to anticancer drugs, including cisplatin (CDDP). Attempts are made herein to evaluate the significance of the enzymes in resistance to CDDP in clinical samples of gastric cancer. A total of 22 gastric cancer specimens, 16 of which were obtained with matching normal mucosae, underwent immunoblotting with polyclonal antibodies against GST-alpha and GST-pi. At the same time, the chemosensitivity of 15 gastric cancer specimens to CDDP was evaluated by the succinic dehydrogenase inhibition (SDI) test. The expression of GST-pi was detected in all the specimens, and its content in the neoplasms exhibited a significant positive correlation with that in the matched normal mucosae. The expression of GST-alpha was detected in 18 of 22 cancer specimens (82%), but its content in the neoplasms did not correlate with that in the matched mucosae. A comparison of the drug-sensitivity findings with the results of immunoblotting revealed a weak but interesting correlation between the protein levels of GST-alpha and CDDP resistance. The cellular content of GST-alpha correlated weakly with CDDP resistance in gastric cancer, and its quantification could contribute to prediction of the clinical effects of CDDP in patients with gastric cancer.
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PMID:Expression of glutathione-S-transferases alpha and pi in gastric cancer: a correlation with cisplatin resistance. 800 52

We retrospectively evaluated the clinical usefulness of the succinate dehydrogenase inhibition (SDI) test as a chemosensitivity test, using 168 resected specimens of gastric cancer, with special reference to the correlation between the results of the SDI test and clinical effects of the corresponding chemotherapy. The rate of sensitivity of these tissues to DDP, CQ, ACR, MMC, ADM, and 5-FU were 63.5%, 54.2%, 47.4%, 42.9%, 31.4%, and 10.8%, respectively. Survival rates for patients with a positive chemosensitivity to MMC and postoperatively prescribed more than 20 mg of MMC were significantly better than those without sensitivity to MMC, even when treated with MMC, although no statistical differences existed in clinicopathologic factors between the two groups. We conclude that the SDI test for human gastric cancer is a rapid, reliable, and useful assay to determine the compatibility between the results of assay and the clinical effects of corresponding chemotherapy. We propose that the regimen of postoperative adjuvant chemotherapy be tailored according to results of the SDI test, using tissues resected from individual patients.
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PMID:Clinical value of SDI test for predicting effect of postoperative chemotherapy for patients with gastric cancer. 805 84


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