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 this study, levels of lipid peroxidation and antioxidant enzyme activities were investigated in the erythrocytes of patients with oesophageal and gastric cancers. Erythrocytes were obtained from 17 patients with oesophageal cancer, 37 patients with gastric cancer and 20 healthy controls. Levels of malondialdehyde (MDA), a lipid peroxidation marker, and activities of copper- and zinc-containing superoxide dismutase (CuZn-SOD), catalase (CAT) and glutathione peroxidase (GPx) were determined using spectrophotometric methods. MDA levels and CuZn-SOD activity were significantly higher and GPx and CAT activities significantly lower in patients with oesophageal and gastric cancer than in controls. There were no statistically significant differences in the parameters measured in relation to disease stage in either patient group. These results indicate significant changes in the antioxidant defence system in patients with oesophageal and gastric cancer. It is postulated that this may lead to enhanced action of oxygen radicals, resulting in lipid peroxidation.
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PMID:Antioxidant enzyme activities and lipid peroxidation levels in erythrocytes of patients with oesophageal and gastric cancer. 1674 15

In the present study, total nitrate and nitrite level (as end product of nitric oxide), superoxide dismutase activity, and glutathione peroxidase activity in leukocytes were determined in patients with gastric cancer, and the relationship between measured parameters and tumor grade were evaluated. Leukocyte nitrate and nitrite level was found to be increased and superoxide dismutase activity was found to be decreased in patients compared to controls. When the patient group was categorized, nitrate and nitrite level was found to be higher in patients with a high-grade tumor than in patients with a grade I tumor. We concluded that an increased level of leukocyte nitrate and nitrite is related to tumor grade in patients with gastric cancer; antioxidant activity is also impaired in these patients but it does not seem to be related to grade of tumor.
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PMID:Nitric oxide and antioxidant defense in patients with gastric cancer. 1686 32

Gastric cancer is the second most common cancer worldwide. The involvement of reactive oxygen species (ROS) in the pathogenesis of gastric malignancies is well known. Many human tumours have shown significant changes in the activity and expression of superoxide dismutase (SOD), which might be correlated with clinical-pathological parameters for the prognosis of human carcinoma. The aim of this study is the detection of MnSOD and CuZnSOD activity and their expression in gastric adenocarcinoma and healthy tissues. Gastric samples (adenocarcinoma and healthy tissues) harvested during endoscopy or resected during surgery were used to determine MnSOD and CuZnSOD activity and expression by spectrophotometric and Western blotting assays. The total SOD activity was significantly higher (p<0.05) in healthy mucosa with respect to gastric adenocarcinomas. No differences were found in MnSOD activity and, on the contrary, CuZnSOD activity was significantly lower (p<0.001) in cancer samples with respect to normal mucosa. The rate of MnSOD/CuZnSOD activity in adenocarcinoma was over ninefold higher than that registered in healthy tissues (p<0.05). Moreover, in adenocarcinoma MnSOD activity represented the 83% of total SOD with respect to healthy tissues where the ratio was 52% (p<0.001). On the contrary, in cancer tissues, CuZnSOD activity accounted for only 17% of the total SOD (p<0.001 if compared with the values recorded in normal mucosa). After immunoblotting, MnSOD was more expressed in adenocarcinoma with respect to normal mucosa (p<0.001), while CuZnSOD was similarly expressed in adenocarcinoma and healthy tissues. The SOD activity assay might provide a specific and sensitive method of analysis that allows the differentiation of healthy tissue from tumour tissue. The MnSOD to CuZnSOD activity ratio, and the ratio between these two isoforms and total SOD, presented in this preliminary study might be considered in the identification of cancerous from healthy control tissue.
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PMID:Superoxide dismutase in gastric adenocarcinoma: is it a clinical biomarker in the development of cancer? 1705 76

Helicobacter pylori (H. pylori) infection, the main cause of chronic gastritis, increases gastric cancer risk. The infection causes inflammatory cells to produce reactive oxygen metabolites that may damage DNA and promote carcinogenesis. However, its precise role in gastric carcinogenesis is as yet unknown. Recently we reported that H. pylori water extract (HPE) has an initiating activity on two-stage mouse skin carcinogenesis. In this study, we investigated the effects of anti-oxidants, ascorbic acid and a combination of superoxide dismutase (CuZnSOD)and catalase, on two-stage mouse skin carcinogenesis. Ascorbic acid and CuZnSOD/catalase were given to mice during the period of HPE-initiation. Both the ascorbic acid and CuZnSOD/catalase treatment attenuated the incidence of tumor formation. The present results suggest that HPE induces tumor formation via reactive oxygen species (ROS) production.
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PMID:Role of oxygen-derived free radicals in Helicobacter pylori water extract-induced mouse skin carcinogenesis. 1726 88

Oxidant/antioxidant balance has been suggested as an important factor for initiation and progression of cancer. In order to determine whether the degree of oxidative DNA damage and antioxidant enzyme activities in plasma obtained from patients with gastric and colon cancer who undergo resection can be used as a useful prognostic predictor, plasma level of 8-hydroxydeoxyguanosine (8-OHdG), activities of glutathione peroxidase (G-Px) and superoxide dismutase (SOD) were examined. 19 patients with gastric cancer and 26 patients with colon cancer who were undergoing resection of tumor were included by the study. Venous blood samples were taken just before the surgery. Plasma level of 8-OHdG was determined with ELISA, SOD and G-Px activities in plasma were measured by spectrophotometric kits. 8-OHdG level and activity of G-Px were found to be decreased, SOD activity was found to be increased in both gastric and colon cancer groups as compared to control group. Alpha fetoprotein was found to be correlated with G-Px in the gastric cancer group and correlated with 8-OHdG in the colon cancer group. SOD activity was correlated with CA-15-3 in the gastric cancer group. Low plasma level of 8-OHdG and altered antioxidant activity may implicate the deficient repair of oxidative DNA damage in patients with gastric and colon cancer. Those measured parameters were not found to be related with histopathological data but correlated with some tumor markers.
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PMID:Prognostic significances of oxidative DNA damage evaluated by 8-hydroxy-deoxyguanosine and antioxidant enzymes in patients undergoing resection of gastric and colon carcinoma. 1731 86

The authors presented in the article results of assessment of metal contained enzymes with antioxidant activity, ceruloplasmin (CP) in plasma blood, Cu-Zn superoxide dismutase (SOD) and catalase in red blood cells of patients with I-IV stage stomach cancer during surgical treatment and application of anticancer autovaccine (AAV) to prevent relapses and methastases. It was revealed compared with the donors that at stages of the treatment, before operation and after resuscitation, the level of activity of CP was higher in 1,3 times and in 3 times was higher the level of SOD. The change of catalase activity was within the limits of physiological values. Discrepancy in levels of activity of enzymes- synergists in relation to the elimination of radical forms testifies about the disbalance in functioning of the antioxidant system protection and is one of the signs of the manifestation of oxidant stress. The presence of wide ranges of changes in activity of metal contained enzymes before surgical operation and after resuscitation may depict the presence of significant tension in the functioning of antioxidant system in patients and may demand to carry out an analysis of each parameter. Normalization or stabilization of the level of activity of metal contained enzymes at the stage of surgical treatment or during the use of AAV reflects an availability of adaptation and compensatory mechanisms and it may be considered as a favorable prognostic factor of the treatment. The use of AAV in a complex treatment of patients with not local stomach canser lead to 3 years survival by 22% in comparison with surgical treatment of the patients.
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PMID:[Functional activity of metal contained enzymes with antioxidant activity in blood of patients with stomach cancer and during the use of anticancer autovaccine]. 1866 38

We prepared an anticancer drug based on a pH-sensitive liposome retaining Fe-porphyrin as an SOD mimic. The liposomes contained cationic/anionic lipid combinations and were composed of Fe-porphyrin, 1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine, dimethylditetradecylammonium bromide, sodium oleate, and Tween-80. The Fe-porphyrin was released from the liposome at low pH, and the cytotoxicity for cancer cells by the liposome depended on the acidic environments of the endosomes in the cells. Furthermore, although the liposome exhibited an excellent anticancer effect on a gastric cancer cell line, the SOD activity of Fe-porphyrin was shown to have a significant influence on the cytotoxicity toward cancer cells. These findings suggest that the pH-sensitive liposome retaining the Fe-porphyrin as an SOD mimic promises to be a novel anticancer drug for endosomal escape.
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PMID:Preparation of pH-sensitive liposomes retaining SOD mimic and their anticancer effect. 1877 54

The apoptosis-inducing ability of hybrid compounds composed of macrosphelide and thiazole-containing side chain of epothilones was investigated. Among the tested series of hybrid compounds the one containing thiazole side chain at C15 (MSt-2) showed the maximum potency to induce apoptosis, while another containing thiazole side chain at C3 (MSt-6) was less potent. MSt-2 was found to induce apoptosis in human lymphoma (U937) cells in a dose- and time-dependent manner as confirmed by DNA fragmentation analysis. MSt-2 treated cells showed rapid reactive oxygen species (ROS) formation and c-Jun N-terminal kinase (JNK) activation. Furthermore, significant activation of extrinsic pathway as evident by Fas expression and caspase-8 activation was also observed. MSt-2-mediated decreased expression of Bid is an important event for cross talk between intrinsic and extrinsic signaling. N-acetyl-l-cysteine pre-treatment rescued cells from MSt-2-induced ROS formation, mitochondrial membrane potential (Delta psi(m)) loss, Fas expression, caspase-8 and -3 activation and DNA fragmentation. Moreover, antioxidant enzymes catalase and/or superoxide dismutase conjugated with polyethylene glycol also inhibit MSt-2-induced ROS formation, apoptosis and Delta psi(m) loss suggesting thereby pro-oxidant effects of MSt-2. Furthermore, JNK and pan-caspase inhibitors also protect cells from MSt-2-induced apoptosis. In addition to this, MSt-2 was found to be more potent in human colon carcinoma (HCT116) and human gastric cancer (AGS) cells while it has no effect on human normal dermal fibroblast. The important structure-activity relationship observed in the current study which makes MSt-2 more potent than MSt-6 is the position of thiazole side chain and stereochemistry of position 3 in chemical structure. In short the results of our study demonstrate that MSt-2-induced rapid ROS generation and mitochondrial dysfunction in cells trigger events responsible for mitochondria-dependent apoptosis pathway.
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PMID:Mechanism of apoptosis induced by a newly synthesized derivative of macrosphelides with a thiazole side chain. 1901 19

Oxidative stress plays an important role in malignant transformation and is postulated to be associated with increased lipid peroxidation. We determined the effects of chronic cigarette smoking on lipid peroxidation and antioxidant status in 100 male patients with gastric cancer and an equal number of age-matched healthy control subjects. The mean (SD) level of thiobarbituric acid reactive substances (TBARS) was higher in plasma (healthy non-smokers 3.1 [0.2]; healthy smokers 4.6 [0.2]; gastric cancer non-smokers 6.5 [1.0]; gastric cancer smokers 8.9 [3.1]) and erythrocytes (3.3 [0.6]; 4.6 [0.1]; 8.3 [0.9]; 13.2 [5.1]) from gastric cancer patients when compared with control subjects. TBARS level was higher in smokers than non-smoking gastric cancer patients. The activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-treansferase, reduced glutathione, and vitamins A, E and C were decreased in gastric cancer patients who were smokers as compared to other groups (p<0.001). Thus, there occurs lipid peroxidation and possible breakdown of antioxidant status in cigarette smoking, which may increase the risk of gastric cancer.
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PMID:Effect of chronic smoking on lipid peroxidation and antioxidant status in gastric carcinoma patients. 1969 92

In this paper, we describe the methodology of the case and control selection for the first-wave nested case-control study within the JACC Study. Among the subjects participating in the cohort, serum samples of 42,249 subjects (including 39,242 subjects aged between 40 and 79 at the baseline) were suitable for biochemical analysis. We here selected those who had died by 1997 or who were diagnosed with cancer with sera until 1994 as cases. For each case, 3 to 4 controls with sera were randomly selected, with matching for gender, age (as near as possible) and residential area. As a result, 3,144 cases and 10,661 controls (2,867 cases and 10,351 controls were 40 to 79 years old at the baseline) were selected to measure serum IGF-I, IGF-II, IGFBP-3, TGF-b1 and sFas values and total SOD activity. Cases were older and more likely to be men than the JACC Study subjects. Moreover, they were much older than controls because of the age-dependence of susceptibility to death, especially among men. There were more smokers among cases compared with controls, though drinkers at the baseline were fewer. Among deceased cases, cancer was the leading cause of death, followed by cardiovascular diseases. Lung cancer was most frequent among deceased cancer cases and the next most common site was the stomach. The leading cause of cancer incidence was stomach cancer followed by lung cancer. Simple comparison of means and distribution of IGF-I, IGF-II, IGFBP-3, TGF-b1, sFas and total SOD activity between cases and controls revealed total SOD activity and sFas levels of cases to be higher than controls, while for the other components the opposite was found.
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PMID:Selection of cases and controls for the nested case-control study within the Japan Collaborative Cohort Study: the First-wave. 2055 75


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