Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0242379 (lung cancer)
 71,905 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Piperine is a major component of black (Piper nigrum Linn) and long pepper (Piper longum Linn) used widely in various systems of traditional medicine. We have evaluated the effect of piperine on mitochondrial tricarboxylic acid cycle and phase I and glutathione-metabolizing enzymes in Benzo(a)pyrene induced experimental lung carcinogenesis in swiss albino mice. Lung cancer bearing mice showed a significant decrease in the activities of mitochondrial enzymes-isocitrate dehydrogenase (ICDH), -ketoglutarate dehydrogenase (KDH), succinate dehydrogenase (SDH), malate dehydrogenase (MDH) and significantly increased NADPH-Cytochorome reductase (NADPH-C reductase), cytochrome P450 (cyt-p450) and cytochrome b5(cyt-b5). The activities of glutathione-metabolizing enzymes glutathione peroxidase(GPx), glutathione reductase (GR) and glucose-6-phospho dehydrogenase(G6PDH) were significantly lowered in lung-cancer bearing mice when compared with control mice. Piperine supplementation to tumour-induced animals significantly lowered the phase-I enzymes (NADPH-C reductase, cyt-p450 and cyt-b5)) and there was a rise in glutathione-metabolizing enzymes (GPx, GR and G6PDH), which indicated an antitumour and anti-cancer effect. Comparison of normal control mice and mice administered piperine only as drug control showed no significant variations in enzyme activities. Piprine administration to benzo(a)pyrene induced animals significantly increased the activities of mitochondrial enzymes, thereby suggesting its role in mitochondrial energy production.
 ...
PMID:Chemopreventive effect of piperine on mitochondrial TCA cycle and phase-I and glutathione-metabolizing enzymes in benzo(a)pyrene induced lung carcinogenesis in Swiss albino mice. 1588 60

Clinical chemoprevention trials of lung cancer have been somewhat disappointing and the development of highly effective chemopreventive agents is urgently needed. We previously showed that the organoselenium 1,4-phenylenebis(methylene)selenocyanate (p-XSC) is a potent chemopreventive agent in numerous preclinical animal models including a lung tumor model that employs carcinogens found in tobacco smoke. The goal of this study is to define molecular targets that will be highly promising in the design of future chemoprevention trials of non-small cell lung cancer (NSCLC), which is by far the most common type of lung cancer cases. In the present investigation, we showed that p-XSC at several doses (2.5, 5, 10 and 20 microM) including physiological levels (2.5-5.0 microM) of selenium is capable of inhibiting cell growth in a dose-dependent manner and inducing apoptosis in three NSCLC cells (NCI-H460, NCI-1299 and A549). To clarify the mechanism involved at the molecular level, we focused only on NCI-460 cells and examined the effects of p-XSC on markers that are known to be critical in the development of NSCLC. Using western blot analysis, we showed that p-XSC reduced the expression of cyclooxygenase-2 (COX-2) and phospholipase A2 (PLA2); although p-XSC inhibited both Akt and p-Akt but its effect was not significant. Using cDNA microarray approach (3800 genes per array) we found that p-XSC upregulates 22 genes by > or = 2-fold while downregulates 13 genes by < or = 0.5-fold; these altered genes include transcriptional factors, growth factors and those involved in xenobiotic metabolism as well as pro- and anti-apoptotic genes. Expression of selected genes was confirmed by RT-PCR; p-XSC reduced the levels of COX-2, PLA2, NF-kappaB and Cyclin D1 but enhanced the levels of glutathione peroxidase-5. Collectively, the results of this study showed that p-XSC alters several molecular markers in a manner that can account for its inhibitory effect of cell growth and induction of apoptosis; therefore, p-XSC may be considered a promising candidate for clinical chemoprevention of NSCLC.
 ...
PMID:Molecular targets of the chemopreventive agent 1,4-phenylenebis (methylene)-selenocyanate in human non-small cell lung cancer. 1639 72

The present study aimed to determine the alterations of antioxidant activities in erythrocytes from patients with nonsmall cell lung carcinoma (NSCLC). A comparative study of the systemic antioxidant activities in red blood cell lysate from subjects with NSCLC and healthy control subjects was conducted. The antioxidants catalase, superoxide dismutase (SOD) and glutathione peroxidase (GPx) were measured using chemical kinetic reactions under spectrophotometry. In total, 189 cases of mostly advanced-stage IIIB or stage IV NSCLC and 202 healthy controls were studied. In subjects with lung cancer, there was similar catalase activity, lower SOD activity (median (interquartile range) 13.4 (9.0-27.2) versus 48.7 (27.0-64.3) U x (ghaemoglobulin(Hb)(-1)), and higher GPx activity (175.2 (126.6-288.3) versus 49.2 (39.5-59.2) mU x (gHb)(-1)) compared with controls. The antioxidant activities in lung cancer subjects were not associated with age, sex, smoking status, or tumour cell types. However, more advanced disease (stage IV compared with stage IIIB) was associated with lower SOD activity. Using multivariable analysis, the presence of lung cancer independently predicted SOD and GPx activities. In conclusion, nonsmall cell lung carcinoma in Chinese subjects is associated with alterations in systemic antioxidant activities, which may play an important role in carcinogenesis.
 ...
PMID:Disturbance of systemic antioxidant profile in nonsmall cell lung carcinoma. 1700 88

Radiation pneumonitis is an unpredictable complication of radiotherapy for lung cancer and a condition which can cause significant morbidity. The ability to identify patients at a high risk of developing pneumonitis is critical, since it will enable the individualization of the treatment plan. Because the cytotoxic effect of radiation is propagated through reactive oxygen species (ROS) and ROS-driven oxidative stress, the role of antioxidant defense systems in radiation pneumonitis was investigated. Using the pneumonitis-sensitive C3H/HeN mice as a model, we demonstrated that the antioxidant response of the lung correlated well with that of red blood cells (RBC). We then proceeded to test whether differences of RBC antioxidant response would predict the pneumonitis development in patients. Superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT) activities and glutathione in RBC were measured at baseline and then weekly for 6 weeks of treatment in 15 eligible patients receiving concurrent chemo-radiotherapy for unresectable stage III NSCLC. Striking differences were found in the antioxidant activities of RBC with respect to the pneumonitis development. Those who developed pneumonitis showed higher SOD and lower GPX activities at baseline compared to those who did not (3.7 vs 6.8 units/mg for median SOD, 16.5 vs 10.7 nmol/min/mg for median GPX). The functional imbalance of SOD and GPX was displayed consistently throughout the treatment period. The sensitivity and specificity of pneumonitis prediction were further increased when the GPX/SOD ratio was analyzed (pretreatment P = 0.0046). Our results provide a strong rationale to monitor SOD and GPX activities of RBC to identify patients who are at risk of developing pneumonitis, and to implement a strategy of increasing the GPX/SOD ratio in order to lower the risk.
 ...
PMID:High superoxide dismutase and low glutathione peroxidase activities in red blood cells predict susceptibility of lung cancer patients to radiation pneumonitis. 1718 33

Nicotine is the major pharmacologically active substance in cigarette smoke and plays an important etiological role in the development of lung cancer. Incidence of cancer may be related to oxidative damage to host genome by nicotine. These oxidative actions may be modified by the phytochemicals present in food. The present study describes the protective effect of ferulic acid (FA), a naturally occurring nutritional compound on nicotine-induced DNA damage and cellular changes in cultured rat peripheral blood lymphocytes in comparison with N-acetylcysteine (NAC), a well-known antioxidant. One-hour exposure of lymphocytes to nicotine at the doses of 0.125, 0.25, 0.5, 1, 2, 3 and 4 mM induced a statistically significant dose-dependent increase in the levels of thiobarbituric acid reactive substances (TBARS), a lipid peroxidative marker and decrease in the levels of reduced glutathione (GSH), an important endogenous antioxidant. The lowest concentration eliciting significant damage was 1 mM nicotine and maximum damage was observed with 3 mM concentration. Hence, the test concentration was fixed at 3 mM nicotine. We have used 5 different doses of FA (10, 50, 100, 150 and 300 microM) and NAC (0.25, 0.5, 1, 2 and 4 mM) to test their protective effects. In all the groups, FA and NAC showed a dose-dependent inhibitory effect. Maximum protection was observed at the dose of 150 microM FA and 1mM NAC. So, 150 microM FA and 1mM NAC were used for further studies. There was a significant increase in the levels of lipid peroxidative index (TBARS and hydroperoxides (HP)), severity of DNA damage (evaluated by comet assay) in nicotine-treated group, which were significantly decreased in FA and NAC-treated groups. Nicotine treatment significantly decreased the endogenous antioxidant status viz., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), GSH, vitamin A, E and C. Co-administration of FA and NAC to nicotine-treated lymphocytes showed a significant increase in the antioxidant status. The protective effect of FA was merely equal to that of NAC effect. FA and NAC treatment alone did not produce any toxicity to the normal lymphocytes at their effective doses. On the whole, there is overwhelming evidence that FA has the ability to modulate DNA damage and a variety of cellular changes that occur during nicotine-induced toxicity in rat peripheral blood lymphocytes.
 ...
PMID:Protective effect of ferulic acid on nicotine-induced DNA damage and cellular changes in cultured rat peripheral blood lymphocytes: a comparison with N-acetylcysteine. 1722 27

Available data indicate that there are significant differences in individual susceptibility to lung cancer within the human population. It is believed to be underlie by inherited genetic predispositions related to the genetic polymorphism of several enzymes involved in the detoxification and xenobiotic metabolism. In this review, we collect and discuss the evidence reported up to date on the association between lung cancer and genetic polymorphism of cytochromes P450, N-acetyltransferase, glutathione S-transferases, microsomal epoxide hydrolase, NAD(P)H:quinone oxidoreductase, myeloperoxidase and glutathione peroxidase. All these genes might appear to be candidates for lung cancer susceptibility genes, nevertheless, the present state of the art still offers only a limited explanation of the link between such polymorphisms and increased risk of lung cancer.
Lung Cancer 2007 Jul
PMID:Polymorphism of selected enzymes involved in detoxification and biotransformation in relation to lung cancer. 1733 85

The human selenoproteome consists of 25 known selenoproteins, but functions of many of these proteins are not known. Selenoprotein H (SelH) is a recently discovered 14-kDa mammalian protein with no sequence homology to functionally characterized proteins. By sensitive sequence and structure analyses, we identified SelH as a thioredoxin fold-like protein in which a conserved CXXU motif (cysteine separated by two other residues from selenocysteine) corresponds to the CXXC motif in thioredoxins. These data suggest a redox function of SelH. Indeed, a recombinant SelH shows significant glutathione peroxidase activity. In addition, SelH has a conserved RKRK motif in the N-terminal sequence. We cloned wild-type and cysteine mutant forms of SelH either upstream or downstream of green fluorescent protein (GFP) and localized this fusion protein to the nucleus in transfected mammalian cells, whereas mutations in the RKRK motif resulted in the cytosolic protein. Interestingly, the full-length SelH-GFP fusion protein localized specifically to nucleoli, whereas the N-terminal sequence of SelH fused to GFP had a diffuse nucleoplasm location. Northern blot analyses revealed low expression levels of SelH mRNA in various mouse tissues, but it was elevated in the early stages of embryonic development. In addition, SelH mRNA was overexpressed in human prostate cancer LNCaP and mouse lung cancer LCC1 cells. Down-regulation of SelH by RNA interference made LCC1 cells more sensitive to hydrogen peroxide but not to other peroxides tested. Overall, these data establish SelH as a novel nucleolar oxidoreductase and suggest that some functions in this compartment are regulated by redox and dependent on the trace element selenium.
 ...
PMID:Selenoprotein H is a nucleolar thioredoxin-like protein with a unique expression pattern. 1733 53

Susceptibility to apoptosis is an essential prerequisite for successful eradication of tumor cells by chemotherapy. Consequently, resistance to apoptosis has been established as one of the mechanisms responsible for the failure of therapeutic approaches in many types of cancers. In the present study, we investigated the susceptibility of human lung cancer H460 cells to apoptotic cell death induced by cisplatin and determined its regulatory mechanisms. Treatment of the cells with cisplatin induced rapid generation of multiple oxidative species and a concomitant increase in apoptotic cell death. Apoptosis induced by cisplatin was mediated through the mitochondrial death pathway, which requires caspase-9 activation and is regulated by Bcl-2. Cisplatin induced down-regulation of Bcl-2 through a process that involves dephosphorylation and ubiquitination of the protein, which facilitates its degradation by proteasome. This down-regulation was inhibited by antioxidant enzymes catalase and glutathione peroxidase (H(2)O(2) scavenger), but not by superoxide dismutase (O(2)(.) scavenger) or deferoxamine (OH. inhibitor). Electron spin resonance and flow cytometric analyses showed the formation of H(2)O(2) along with O(2)(.) and OH. radicals after cisplatin treatment. H(2)O(2) was generated in part by dismutation of O(2)(.) and served as a precursor for OH.. Together, our results indicate an essential role of H(2)O(2) in the regulation of Bcl-2 and apoptotic cell death induced by cisplatin. Because aberrant expression of Bcl-2 has been associated with death resistance of cancer cells to chemotherapy, the results of this study could be used to aid the design of more effective strategies for cancer treatment.
 ...
PMID:Peroxide is a key mediator of Bcl-2 down-regulation and apoptosis induction by cisplatin in human lung cancer cells. 1791 32

The modulatory efficacy of capsaicin on lung mitochondrial enzyme system with reference to mitochondrial lipid peroxidation (LPO), antioxidants, key citric acid cycle enzymes and respiratory chain enzymes during benzo(a)pyrene (B(a)P) induced lung cancer in Swiss albino mice was studied. Elevations in mitochondrial LPO along with decrements in enzymic antioxidants (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione-S-transferase (GST)), non-enzymic antioxidants (reduced glutathione (GSH), vitamin C, vitamin E and vitamin A), citric acid cycle enzymes (isocitrate dehydrogenase (ICDH), alpha-ketoglutarate dehydrogenase (alpha-KDH), succinate dehydrogenase (SDH) and malate dehydrogenase (MDH)), and respiratory chain enzymes (NADH dehydrogenase and Cytochrome c oxidase) were observed in B(a)P (50mg/kg body weight) administered animals. CAP (10mg/kg body weight) pretreatment decreased lung mitochondrial LPO and augmented the activities of enzymic, non-enzymic antioxidants, citric acid cycle enzymes and respiratory chain enzymes to near normalcy revealing its chemoprotective function during B(a)P induced lung cancer.
 ...
PMID:Stabilization of pulmonary mitochondrial enzyme system by capsaicin during benzo(a)pyrene induced experimental lung cancer. 1802 35

Chemoprevention has emerged as a very effective preventive measure against carcinogenesis. Several bioactive compounds present in fruits and vegetables have revealed their cancer curative potential on benzo(a)pyrene (B(a)P) induced carcinogenesis. In the present study, the efficacy of quercetin on the level of lipid peroxides, activities of antioxidant enzymes and tumor marker enzymes in B(a)P induced experimental lung carcinogenesis in Swiss albino mice was assessed. In lung cancer bearing animals there was an increase in lung weight, lipid peroxidation and marker enzymes such as aryl hydrocarbon hydroxylase, gamma glutamyl transpeptidase, 5'-nucleotidase, lactate dehydrogenase and adenosine deaminase with subsequent decrease in body weight and antioxidant enzymes-superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, glutathione reductase, reduced glutathione, vitamin E and vitamin C. Quercetin supplementation (25 mg/kg body weight) attenuated all these alterations, which indicates the anticancer effect that was further confirmed by histopathological analysis. Overall, the above data shows that the anticancer effect of quercetin is more pronounced when used as an chemopreventive agent rather than as a chemotherapeutic agent against B(a)P induced lung carcinogenesis.
 ...
PMID:The effects of quercetin on antioxidant status and tumor markers in the lung and serum of mice treated with benzo(a)pyrene. 1805 10


<< Previous 1 2 3 4 5 6 7 Next >>