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

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.
Cancer Chemother Pharmacol 1994
PMID:Expression of glutathione-S-transferases alpha and pi in gastric cancer: a correlation with cisplatin resistance. 800 52

It was established that patients with hepatobiliary pathology showed a reduction of SH groups and activity of lymphocyte succinate dehydrogenase of the peripheral blood. The level of this reduction depended on the severity of the pathological process and was lowest in viral hepatitis and cancer of the head of the pancreas. A dynamic study of SH groups and SDG in these groups of patients makes it possible to evaluate disorders of oxidation, oxidation, severity of the disease; it is also of prognostic significance.
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PMID:[The clinical significance of determining sulfhydryl groups and succinate dehydrogenase in the peripheral blood lymphocytes of patients with liver and biliary tract pathology]. 820 51

Metastases in rat liver were generated experimentally by intraportal injection of colon cancer cells to investigate the effects of cancerous growth on the metabolism of surrounding liver tissue. Maximum activities (capacity) of glucose-6-phosphate dehydrogenase, phosphogluconate dehydrogenase, lactate dehydrogenase, succinate dehydrogenase, alkaline phosphatase, 5'-nucleotidase, xanthine oxidoreductase, purine nucleoside phosphorylase and adenosine triphosphatase have been determined. Two types of metastases were found, a small type surrounded by stroma and a larger type in direct contact with hepatocytes. Both types affected the adjacent tissue in a similar way suggesting that the interactions were not mediated by stroma. High capacity of the degradation pathway of extracellular purines released from dead cells of either tumours or host tissue was found in stroma and sinusoidal cells. Metastases induced both an increase in the number of Kupffer cells and proliferation of hepatocytes. The distribution pattern in the liver lobulus of most enzymes investigated did not change distinctly. However, activity of alkaline phosphatase, succinate dehydrogenase and phosphogluconate dehydrogenase was increased in hepatocytes directly surrounding metastases. These data imply that the overall metabolic zonation in liver lobuli is not dramatically disturbed by the presence of cancer cells despite the fact that various metabolic processes in liver cells are affected.
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PMID:Experimentally induced colon cancer metastases in rat liver increase the proliferation rate and capacity for purine catabolism in liver cells. 822 8

The characterization of radiation-induced fibrosarcoma cells (RIF-8A) which have been selected for resistance to Photofrin-mediated photodynamic therapy (PDT) is detailed in this report. Morphological and functional assessment of mitochondria in both the resistant RIF-8A and parental RIF-1 cells show distinct differences. Electron micrographs show that the mitochondria in the RIF-8A cells are relatively smaller; stain more densely, and display a higher cristae density than RIF-1 cells. P. A. Andrews et al. (Cancer Res., 52: 1895-1901, 1992) reported similar mitochondrial differences between a human ovarian carcinoma cell line, 2008, and its cisplatin-resistant counterpart (C13*). Dose-response curves demonstrate that these cisplatin-resistant C13* cells show cross-resistance to Photofrin-mediated PDT. Functionally, the RIF-8A cells produce more ATP and demonstrate higher succinate dehydrogenase activity than do the RIF-1 cells, but the rates of oxygen consumption do not differ between the two cell types. The PDT-sensitive RIF-1 cells demonstrate a significantly higher susceptibility to inhibition of glycolytic activity as determined by 2-deoxy-d-glucose survival curves. These findings suggest differences in the efficacy and/or mode(s) of energy production in the RIF-1 and RIF-8A cells. Since mitochondria are sensitive targets for porphyrin-mediated PDT, the observed changes in mitochondrial structure and/or function may be involved in the PDT resistance seen in RIF-8A cells.
Cancer Res 1993 Oct 15
PMID:Mitochondrial alterations in photodynamic therapy-resistant cells. 840 90

Fluorescent probes were used to detect BUdR-labelled B16F10 and M5076 cancer cells delivered to the livers of mice via intrasplenic injection. In liver sections stained for succinic dehydrogenase, which permits the periportal, acinar zone 1 to be distinguished from the pericentral zone 3, counts were made of the zonal distribution of fluorescent, intact cancer cells and, by default, the numbers of "lost" cells. Very few intact cancer cells leave the liver from the single bolus of the intrasplenic injection, and even fewer of these generate pulmonary lesions; therefore, within the time limits of these experiments, the liver is virtually a closed system. A dynamic view of intrahepatic cancer-cell traffic with respect to zones 1 (periportal) and 3 (pericentral) was obtained from static measurements of cell densities at different times after intrasplenic injection, by means of Markov chain probability analysis. This indicated that, during the first hour after arrival in zone 1 of the liver sinusoids, there is a 10% probability of a B16F10 cell remaining intact in zone 1, an 89% probability of cell death in zone 1 and only a 1% probability of the cell passing into zone 3. During the same period, there is a 77% probability of an M5076 cell remaining intact in zone 1, a 21% probability of death, and a 2% probability of relocation to zone 3. In both cell types, very few cells were lost from zone 3. Further proportional death in zone 1 diminished over the next 23 hr, concomitant with an increased proportion of cell death in zone 3. Our results indicate that, although there is considerable variation between the 2 cell types studied here, most (B16) or many (M5076) of these cancer cells entering the liver via the portal vein die within 1 hr in zone 1 of liver lobules. In addition, very few of the cells delivered to zone 1 travel along the sinusoids to zone 3, and few of these reach the lungs in a viable state.
Int J Cancer 1993 Jan 21
PMID:Cancer-cell traffic in the liver. II. Arrest, transit and death of B16F10 and M5076 cells in the sinusoids. 842 68

The results of two types of in vitro chemosensitivity tests, namely, the human tumor clonogenic assay (HTCA) and the succinic dehydrogenase inhibition assay (SDIA), for solid tumors, including stomach, colorectal and lung cancers, were analyzed and their correlation with clinical effects evaluated. The anticancer agents employed were mitomycin C (MMC), 5-fluorouracil (5-FU), adriamycin (ADM) and cisplatin (DDP). The evaluability rates of the assays were 54.5% for HTCA and 89.0% for SDIA. Among the 29 cases with evaluable lesions subjected to HTCA, there were 4 true positives, 9 false positives, and 16 true negatives, whereas among the 32 cases subjected to SDIA, the corresponding numbers were 2, 6, and 24, respectively. There were no false negatives for either assay, the accuracy of prediction for HTCA being 69.0% and for SDIA, 81.3%. The true positives of both assays included one complete response (CR) and five partial responses (PR), although the eventual outcome was cancer death in all cases. Interestingly, in five out of the six true positive cases, the agent involved was either ADM or DDP, both the which are usually regarded as "second line" anticancer agents for gastrointestinal carcinomas.
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PMID:The predictability of clinical antitumor effects using two distinctive in vitro chemosensitivity tests: an analysis of true positive cases. 846 69

Hypoxic tumor cells resist most therapies and cause tumor regrowth when their environment improves. Identifying the adaptation strategies to hypoxia would help develop better tailored cancer therapies. Ehrlich carcinomas implanted on mice were analyzed histochemically for the following enzyme activities: lactate, succinate and glucose-6-phosphate dehydrogenases, dihydrofolate reductase, purine nucleoside phosphorylase, xanthine oxidoreductase, and acid phosphatase. With the exception of xanthine oxidoreductase, which was not active in tumor cells, and of succinate dehydrogenase the activity of which was not significatively altered, all other activities were much higher in perinecrotic cells with respect to cells close to blood vessels. These data suggest the integration of metabolic paths allowing purine and lipid biosyntheses. Degradation products from the necrosis are presumed to be employed as surrogates of blood-borne nutritive substances by cells distant from the vascularization.
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PMID:Characterization of the metabolism of perinecrotic cells in solid tumors by enzyme histochemistry. 869 18

With a view to locate porphyrins for use in photodynamic therapy (PDT), the new modality of cancer treatment we have evaluated the ability of a novel water soluble porphyrin meso-tetrakis[4-(carboxymethyleneoxy)phenyl]porphyrin (T4CPP) to induce damage to mitochondria during photosensitization. T4CPP, when exposed to visible light, induced lipid peroxidation in rat liver mitochondria as assessed by the formation of thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD) and lipid hydroperoxides (LOOH). The effect on mitochondrial function was assessed by estimating the activity of succinate dehydrogenase (SDH). The peroxidation induced was observed to be time- and concentration- dependent. Analysis of product formation and selective inhibition by scavengers of reactive oxygen species showed that the oxidative damage observed was mainly due to singlet oxygen ((1)O2) and partly due to other reactive species. T4CPP plus light also caused significant lipid peroxidation in Sarcoma 180 ascites tumour mitochondria. Our studies indicate that T4CPP has the potential to photoinduce damage in hepatic and ascites mitochondria, a crucial site of damage in PDT.
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PMID:Lipid peroxidation induced by a novel porphyrin plus light in isolated mitochondria: possible implications in photodynamic therapy. 904 18

A cis-diamminedichloroplatinum (CDDP)-resistant scirrhous gastric cancer cell line, OCUM-2M/DDP, was established by chronic exposure of cells of the parent scirrhous gastric cancer cell line, OCUM-2M, to CDDP at progressively increasing concentrations. The OCUM-2M/DDP cell line had an 11.3-fold higher level of resistance relative to its parent cell line as determined by a succinate dehydrogenase inhibition test. The biological and biochemical characteristics of the resistant and parent cell line were compared. There were differences in the modal chromosome number and DNA index, suggesting that some alterations of the DNA in the CDDP-resistant cells had occurred. Neither the parent nor resistant cell line expressed mdr-1 mRNA. After exposure to CDDP for 4 h, the intracellular platinum content of OCUM-2M cells was significantly higher than that of OCUM-2M/DDP cells (51.9 +/- 1.8 vs 16.4 plus 1.0 ng/mg protein, mean +/- SD, respectively). The GSH levels in OCUM-2M cells and OCUM-2M/DDP cells were 3.5 +/- 1.0 micrograms/mg protein and 16.8 +/- 1.2 micrograms/mg protein, respectively. These levels were also significantly different. These findings suggest that the possible mechanisms of acquired resistance to CDDP in OCUM-2M/DDP cells may be a decrease in intracellular CDDP accumulation and detoxication by GSH. This OCUM-2M/DDP cell line could be used in further investigations of the mechanism of CDDP resistance in gastric cancer.
Cancer Chemother Pharmacol 1997
PMID:Establishment of a cisplatin-resistant gastric carcinoma cell line OCUM-2M/DDP. 913 37

Tetra(m-hydroxyphenyl)chlorin (mTHPC) is used as a photosensitizer in photodynamic therapy (PDT), a novel modality for cancer treatment. Since little is known about mTHPC-mediated damage in vitro, we chose isolated rat liver mitochondria as a model system to study its photodynamic effects. Incubation of isolated mitochondria with mTHPC plus irradiation with light of a wavelength of 652 nm resulted in protein oxidation and lipid peroxidation, as measured by the mitochondrial content of carbonyl groups and thiobarbituric acid-reactive substances, respectively. Type I and type II photochemical reactions contribute to this oxidative damage as shown by the use of scavengers. Photodynamically treated mitochondria had a reduced membrane potential, and their Ca2+ uptake was impaired. Oxygen consumption of complex I of the respiratory chain was stimulated at a low concentration of mTHPC plus irradiation, but decreased at higher concentrations, whereas oxygen consumption at complex II and IV decreased with all mTHPC concentrations offered. No mitochondrial changes were seen with mTHPC in the absence of irradiation. Our results confirm the sensitivity of mitochondria to PDT and may help to understand the mechanisms by which PDT using mTHPC kills cells.
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PMID:Photosensitization of isolated rat liver mitochondria by tetra(m-hydroxyphenyl)chlorin. 943 43


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