Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:1.1.1.1 (alcohol dehydrogenase)
9,284 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

One suggested mechanism underlying the positive association between alcohol consumption and breast cancer risk is an influence of alcohol on steroid hormone levels. A polymorphism in alcohol dehydrogenase type 3 (ADH3) affects the kinetics of alcohol oxidation and thereby could influence the effect of alcohol consumption on hormone levels. We investigated the ADH3 polymorphism, alcohol intake, and risk of breast cancer in a nested case-control study. Among women in the Nurses' Health Study who gave a blood sample in 1989-1990, 465 incident breast cancer cases were diagnosed before June 1994 and were matched to 621 controls. Using conditional logistic regression, we calculated relative risks and confidence intervals to assess breast cancer risk for ADH3 genotype. Among postmenopausal controls not using hormones at time of blood collection, partial Pearson correlation coefficients were calculated to assess the association between alcohol intake and plasma hormone levels according to ADH3 genotype. No association was observed between ADH3 genotype and overall breast cancer risk (relative risk = 0.9 for slow oxidizers compared with fast; 95% confidence interval = 0.6-1.3). Among postmenopausal women, ADH3 genotype did not modify the weak association observed between alcohol intake and breast cancer risk (P for interaction = 0.45). Statistically significant trends in the relationship between alcohol consumption and hormone level dependent on oxidative capacity (ADH3 genotype) were observed for dehydroepiandrosterone sulfate and sex hormone-binding globulin (P < 0.05). These data suggest that the ADH3 polymorphism modestly influences the response of some plasma hormones to alcohol consumption but is not independently associated with breast cancer risk and does not modify the association between alcohol and breast cancer risk.
Cancer Epidemiol Biomarkers Prev 2000 Oct
PMID:A prospective study of the effect of alcohol consumption and ADH3 genotype on plasma steroid hormone levels and breast cancer risk. 1104 94

Many epidemiological studies have identified chronic alcohol consumption as a significant risk factor for cancer of the upper aerodigestive tract (UAT) in human. Although acetaldehyde, the first metabolite from ethanol by alcohol dehydrogenase (ADH), is regarded as a carcinogen, how systemic production of acetaldehyde particularly affects the UAT remains unclear. In our study, we searched for the regional source of acetaldehyde in UAT, especially the involvement of bacteria in the human normal oral microflora. Here we demonstrate that, among the bacterial species identified from the human oral cavity, genus Neisseria had extremely high ADH activity and produced significant amounts of acetaldehyde when cultured with medium containing ethanol in vitro. The ability to produce acetaldehyde was more than 100-fold higher than that produced by any other genera we studied. Furthermore, alcohol ingestion influences the bacterial composition of the oral microflora, resulting in an increased proportion of Neisseria. Although Neisseria present in normal oral microflora is generally non-pathogenic, these findings suggest that this microbe can be a regional source of carcinogenic acetaldehyde and thus potentially play an important role in alcohol-related carcinogenesis in human UAT.
Int J Cancer 2000 Nov 01
PMID:Acetaldehyde production by non-pathogenic Neisseria in human oral microflora: implications for carcinogenesis in upper aerodigestive tract. 1105 61

To determine how hyaluronidase increases certain cancer cell sensitivity to tumor necrosis factor (TNF) cytotoxicity, we report here the isolation and characterization of a hyaluronidase-induced murine WW domain-containing oxidoreductase (WOX1). WOX1 is composed of two N-terminal WW domains, a nuclear localization sequence, and a C-terminal alcohol dehydrogenase (ADH) domain. WOX1 is mainly located in the mitochondria, and the mitochondrial targeting sequence was mapped within the ADH domain. Induction of mitochondrial permeability transition by TNF, staurosporine, and atractyloside resulted in WOX1 release from mitochondria and subsequent nuclear translocation. TNF-mediated WOX1 nuclear translocation occurred shortly after that of nuclear factor-kappaB nuclear translocation, whereas both were independent events. WOX1 enhanced TNF cytotoxicity in L929 cells via its WW and ADH domains as determined using stable cell transfectants. In parallel with this observation, WOX1 also enhanced TRADD (TNF receptor-associated death domain protein)-mediated cell death in transient expression experiments. Antisense expression of WOX1 raised TNF resistance in L929 cells. Enhancement of TNF cytotoxicity by WOX1 is due, in part, to its significant down-regulation of the apoptosis inhibitors Bcl-2 and Bcl-x(L) (>85%), but up-regulation of pro-apoptotic p53 ( approximately 200%) by the ADH domain. When overexpressed, the ADH domain mediated apoptosis, probably due to modulation of expression of these proteins. The WW domains failed to modulate the expression of these proteins, but sensitized COS-7 cells to TNF killing and mediated apoptosis in various cancer cells independently of caspases. Transient cotransfection of cells with both p53 and WOX1 induced apoptosis in a synergistic manner. WOX1 colocalizes with p53 in the cytosol and binds to the proline-rich region of p53 via its WW domains. Blocking of WOX1 expression by antisense mRNA abolished p53 apoptosis. Thus, WOX1 is a mitochondrial apoptogenic protein and an essential partner of p53 in cell death.
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PMID:Hyaluronidase induction of a WW domain-containing oxidoreductase that enhances tumor necrosis factor cytotoxicity. 1105 90

The human aldo-keto reductase AKR1C1 (20alpha(3alpha)-hydroxysteroid dehydrogenase) is induced by electrophilic Michael acceptors and reactive oxygen species (ROS) via a presumptive antioxidant response element (Burczynski, M. E., Lin, H. K., and Penning, T. M. (1999) Cancer Res. 59, 607-614). Physiologically, AKR1C1 regulates progesterone action by converting the hormone into its inactive metabolite 20alpha-hydroxyprogesterone, and toxicologically this enzyme activates polycyclic aromatic hydrocarbon trans-dihydrodiols to redox-cycling o-quinones. However, the significance of its potent induction by Michael acceptors and oxidative stress is unknown. 4-Hydroxy-2-nonenal (HNE) and other alpha,beta-unsaturated aldehydes produced during lipid peroxidation were reduced by AKR1C1 with high catalytic efficiency. Kinetic studies revealed that AKR1C1 reduced HNE (K(m) = 34 microm, k(cat) = 8.8 min(-1)) with a k(cat)/K(m) similar to that for 20alpha-hydroxysteroids. Six other homogeneous recombinant AKRs were examined for their ability to reduce HNE. Of these, AKR1C1 possessed one of the highest specific activities and was the only isoform induced by oxidative stress and by agents that deplete glutathione (ethacrynic acid). Several hydroxysteroid dehydrogenases of the AKR1C subfamily catalyzed the reduction of HNE with higher activity than aldehyde reductase (AKR1A1). NMR spectroscopy identified the product of the NADPH-dependent reduction of HNE as 1,4-dihydroxy-2-nonene. The K(m) of recombinant AKR1C1 for nicotinamide cofactors (K(m) NADPH approximately 6 microm, K(m)(app) NADH >6 mm) suggested that it is primed for reductive metabolism of HNE. Isoform-specific reverse transcription-polymerase chain reaction showed that exposure of HepG2 cells to HNE resulted in elevated levels of AKR1C1 mRNA. Thus, HNE induces its own metabolism via AKR1C1, and this enzyme may play a hitherto unrecognized role in a response mounted to counter oxidative stress. AKRs represent alternative GSH-independent/NADPH-dependent routes for the reductive elimination of HNE. Of these, AKR1C1 provides an inducible cytosolic barrier to HNE following ROS exposure.
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PMID:The reactive oxygen species--and Michael acceptor-inducible human aldo-keto reductase AKR1C1 reduces the alpha,beta-unsaturated aldehyde 4-hydroxy-2-nonenal to 1,4-dihydroxy-2-nonene. 1106 Feb 93

Genetic polymorphism of carcinogen-metabolizing enzymes is one of the important aspects of the genetic susceptibility to cancer. The enzymes involved in alcohol metabolism include mainly alcohol dehydrogenase(ADH), aldehyde dehydrogenase(ALDH) and cytochrome P450 2E1(CYP2E1), which all appear to be polymorphic. Several recent studies show that the genetic polymorphisms of alcohol-metabolizing enzymes are associated with some cancers such as liver cancer, stomach cancer and esophageal cancer. But there are also the inconsistent results.
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PMID:[Progress in researches on the relationship between genetic polymorphisms of alcohol-metabolizing enzymes and cancers]. 1117 47

A 15-year-old girl developed acute lymphoblastic leukemia (ALL). The patient was treated according to the 13th protocol of the Tokyo Children's Cancer Study Group, and thereafter remained free of disease. However, at the age of 20, she complained of polyuria, polydipsia and amenorrhea. Hematological or meningeal relapse was ruled out on the basis of clinical and laboratory findings. The plasma concentrations of GH, TSH, LH, FSH, ACTH and ADH were low or below the detectable limits. There was no increase in urine osmolarity after water deprivation. Arginine, LH-RH, TRH and CRH tolerance tests revealed no or low responses of GH, LH/FSH, TSH, and ACTH/cortisol, respectively. Magnetic resonance imaging demonstrated thickening of the pituitary stalk, which was homogeneously enhanced by gadolinium administration. A biopsy specimen showed fibrosis and infiltration of CD8-positive T lymphocytes in a portion of the pituitary stalk, whereas the adenohypophysis was normal. In addition, no leukemic cells were observed in the samples. Thus, a diagnosis of lymphocytic infundibuloneurohyophysitis (LIN) was established. All the symptoms were improved by treatment with hydrocortisone, L-thyroxine, desamino-8-d-arginine vasopressin, estrogen and gestagen. This is the first reported case of ALL complicated by LIN.
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PMID:[Lymphocytic infundibuloneurohypophysitis during the first remission in acute lymphoblastic leukemia]. 1119 41

Membrane lipid peroxidation results in the production of a variety of aldehydic compounds that play a significant role in aging, drug toxicity and the pathogenesis of a number of human diseases, such as atherosclerosis and cancer. Increased lipid peroxidation and reduced antioxidant status may also contribute to the development of diabetic complications. This study reports that lipid peroxidation end products such as malondialdehyde (MDA) and 4-hydroxynonenal (HNE) induce aldehyde reductase (ALR) gene expression. MDA and HNE induce an increase in intracellular peroxide levels; N-Acetyl-L-cysteine (NAC) suppressed MDA- and HNE-induced ALR gene expression. These results indicate that increased levels of intracellular peroxides by MDA and HNE might be involved in the upregulation of ALR.
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PMID:Aldehyde reductase gene expression by lipid peroxidation end products, MDA and HNE. 1123 96

Alcohol is one of the major risk factors for oral and pharyngeal cancer. The rate-limiting step in alcohol metabolism is the oxidation (activation) of ethanol to acetaldehyde by the alcohol dehydrogenases (ADHs). It has been hypothesized that individuals who are homozygous for the fast allele (ADH(1-1)(3)) are at greater risk for alcohol-related cancers. To test this hypothesis, we investigated the association between the ADH3 genotype and oral and pharyngeal cancer risk in a large racially homogeneous case-control study of 229 patients and 575 matched control subjects with frequency matching on age, sex, and smoking status. Although the smoking status was matched between cases and controls, current and former alcohol use remained a significant risk factor, compared with never use (odds ratio, 2.08; 95% confidence interval, 1.37-3.17; odds ratio, 1.97; 95% confidence interval, 1.25-3.09; and odds ratio, 1.00, respectively). The ADH1(3) allele frequency of controls was 57.4%, consistent with reports of similar racial groups (50-60%). The genotype distribution in controls was also consistent with the Hardy-Weinberg equilibrium (P = 0.51). However, the ADH1(3) allele frequency and ADH(1-1)(3) genotype frequency were not significantly different between cases and controls [55.5% versus 57.4% (P = 0.52), and 30.6% versus 31.3% (P = 0.91), respectively]. There was no association between ADH3 genotypes (ADH(1-1)(3), ADH(1-2)(3), and ADH(2-2)(3)) and risk of oral and pharyngeal cancer (odds ratios, 1.00; 0.96; 95% confidence interval, 0.68-1.37; and odds ratio, 1.23; confidence interval, 0.78-1.93, respectively). Therefore, we found no evidence that supports a main effect of ADH3 genotype or a combined effect of alcohol and ADH3 genotype on risk of cancer of the oral cavity or pharynx.
Cancer Epidemiol Biomarkers Prev 2001 Mar
PMID:Alcohol dehydrogenase 3 genotype is not associated with risk of squamous cell carcinoma of the oral cavity and pharynx. 1130 99

Liver alcohol dehydrogenase (E.C.1.1.1.1) is an NAD(+)/NADH dependent enzyme with a broad substrate specificity being active on an assortment of primary and secondary alcohols. It catalyzes the reversible oxidation of a wide variety of alcohols to the corresponding aldehydes and ketones as well as the oxidation of certain aldehydes to their related carboxylic acids. Although the bioinorganic and bioorganic aspects of the enzymatic mechanism, as well as the structures of various ternary complexes, have been extensively studied, the kinetic significance of certain intermediates has not been fully evaluated. Nevertheless, the availability of computer-assisted programs for kinetic simulation and molecular modeling make it possible to describe the biochemical mechanism more completely. Although the true physiological substrates of this zinc metalloenzyme are unknown, alcohol dehydrogenase effectively catalyzes not only the interconversion of all-trans-retinol and all-trans-retinal but also the oxidation of all-trans-retinal to the corresponding retinoic acid. Retinal and related vitamin A derivatives play fundamental roles in many physiological processes, most notably the vision process. Furthermore, retinoic acid is used in dermatology as well as in the prevention and treatment of different types of cancer. The enzyme-NAD(+)-retinol complex has an apparent pK(a) value of 7.2 and loses a proton rapidly. Proton inventory modeling suggests that the transition state for the hydride transfer step has a partial negative charge on the oxygen of retinoxide. Spectral evidence for an intermediate such as E-NAD(+)-retinoxide was obtained with enzyme that has cobalt(II) substituted for the active site zinc(II). Biophysical considerations of water in these biological processes coupled with the inverse solvent isotope effect lead to the conclusion that the zinc-bound alkoxide makes a strong hydrogen bond with the hydroxyl group of Ser48 and is thus activated for hydride transfer. Moderate pressure accelerates enzyme action indicative of a negative volume of activation. The data with retinol is discussed in terms of enzyme stability, mechanism, adaptation to extreme conditions, as well as water affinities of substrates and inhibitors. Our data concern all-trans, 9-cis, 11-cis, and 13-cis retinols as well as the corresponding retinals. In all cases the enzyme utilizes an approximately ordered mechanism for retinol-retinal interconversion and for retinal-retinoic acid transformation.
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PMID:Bioinorganic and bioorganic studies of liver alcohol dehydrogenase. 1130 60

Oxidation of the mycotoxin aflatoxin (AF) B1 yields the 8,9-epoxide, which nonenzymatically hydrolyzes rapidly to a dihydrodiol that in turn undergoes slow, base-catalyzed ring opening to a dialdehyde [Johnson, W. W., Harris, T. M., and Guengerich F. P. (1996) J. Am. Chem. Soc. 118, 8213-8220]. AFB1 dialdehyde does not bind to DNA but can react with protein lysine groups. One enzyme induced by cancer chemopreventive agents is AFB1 aldehyde reductase (AFAR), which catalyzes the NADPH-dependent reduction of the dialdehyde to a dialcohol. AFB1 dialdehyde is known to convert nonenzymatically to AFB1 dihydrodiol at neutral pH, and we reinvestigated the enzymatic reaction by preparing AFB1 dialdehyde at pH 10 and then used this to initiate reactions (at neutral pH) with rat and human AFAR isozymes. Two monoalcohols were identified as products, and their identities were established by NaB2H4 reduction, chemical cleavage, and mass spectrometry. The monoalcohol corresponding to reduction at C-8 formed first in reactions catalyzed by either the rat or the human AFAR. This C-8 monoalcohol was further reduced to AFB1 dialcohol by AFAR. The other monoalcohol (C-6a) was formed but not reduced to the dialcohol rapidly. Steady-state kinetic parameters were estimated for the reduction of AFB1 dialdehyde by rat and human AFAR to the monoalcohols. The apparent k(cat) and K(m) values were not adequate to rationalize the observed DeltaA(340) spectral changes in a kinetic model. Simulation fitting was done and yielded parameters indicative of greater enzyme efficiency. A survey of 12 human liver cytosol samples showed a variation of 2.3-fold in AFAR activity. Rats treated with AFB1 excreted the dialcohol and a monoalcohol in urine. The results of these studies are consistent with a role of (rat and human) AFAR in protection against AFB1 toxicity.
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PMID:Reduction of aflatoxin B1 dialdehyde by rat and human aldo-keto reductases. 1140 44


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