Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A congenital erythrocyte pyruvate kinase (PK) deficiency was found in a 72-year old female patient with chronic myelomonocytic leukemia (CMML). Erythrocyte PK deficiency was associated with an increase in the activity of hexokinase, 6-phosphogluconate dehydrogenase and glutathione peroxidase in erythrocytes as well as a decrease in acetylcholinesterase, glutathione reductase and glucosephosphate isomerase activities. The enzymatic abnormalities were accompanied by alterations in hemoglobin and in i antigen content of erythrocyte membrane. In addition, bone marrow ultrastructural studies showed dyshemopoietic changes in all blood cell lines and especially in erythroblasts. The present findings confirm the close relationship between CMML and acquired dyserythropoietic syndromes and constitute a new observation of the infrequent association of hereditary erythrocyte enzymopathies and leukemia. A survey of the literature is presented.
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PMID:Chronic myelomonocytic leukemia associated with hereditary pyruvate kinase deficiency and multiple acquired erythrocyte abnormalities. 10 94

In a series of 841 patients with hematologic disorders, 10 individuals were found to have an extra C group chromosome in their bone marrow cells. In two the extra chromosome was not identified, but in the remaining eight it was No. 8. Four of these ten patients had leukemia, and the others had cytopenias or other probably preleukemic conditions. The mean value for glutathione reductase activity in the red cells of four patients with trisomy 8 was significantly higher (2980 +/- 940 mumoles/min/liter of erythrocytes) than in normal controls (1930 +/- 360) or in any of five different control groups of patients with hematologic disorders. The extent of enzyme activation as a result of preincubation with exogenous flavin adenine dinucleotide was similar in the erythrocytes of all groups. The reasons for the high values of red cell glutathione reductase activity in patients with trisomy 8 are discussed in the light of the proposed assignment of the gene for that enzyme to chromosome 8.
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PMID:Trisomy 8 in the bone marrow associated with high red cell glutathione reductase activity. 106 47

Oxidative biotransformation of xenobiotics and endogenous substances involves glutathione in reduced form as an integral component through two mechanisms: glutathione peroxidase catalysing the reduction of hydrogen peroxide and organic hydroperoxides, and glutathione-S-transferases catalysing the conjugation of oxygenated derivatives with glutathione. We studied glutathione and glutathione-related enzyme activities in haemolysed venous blood samples from 49 healthy children and from 11 children with diabetes mellitus, 10 children with rheumatoid arthritis, seven children with active coeliac disease, and seven children with acute lymphoblastic leukaemia. Among the healthy children glutathione content and the activities of glutathione reductase, glutathione peroxidase, and glutathione-S-transferase were unrelated to sex; age-dependent differences were also minor. The patients with diabetes mellitus had decreased activity of glutathione reductase. The patients with acute lymphoblastic leukaemia had increased activity of both glutathione peroxidase and glutathione-S-transferase, possibly reflecting an adaptive response to free-radicals. The patients with active coeliac disease had control levels of all measured parameters of glutathione-related reactions indicating, since we earlier found decreased activities of glutathione peroxidase in intestinal mucosa of celiacs, that blood may not always reflect tissue-specific changes.
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PMID:Glutathione and glutathione-metabolizing enzymes in the erythrocytes of healthy children and in children with insulin-dependent diabetes mellitus, juvenile rheumatoid arthritis, coeliac disease and acute lymphoblastic leukaemia. 204 16

N,N'-Bis(trans-4-hydroxycyclohexyl)-N'-nitrosourea (BHCNU) is a nitrosourea which has carbamoylating but not alkylating activity. It has been shown to carbamoylate and inactivate glutathione reductase thereby reducing the intracellular levels of glutathione (GSH). Since GSH depletion by buthionine-S,R-sulfoximine potentiates the cytotoxicity of cyclophosphamide, with a corresponding increase in DNA cross-linking, we have investigated the potential interaction between BHCNU and cyclophosphamide. Treatment of K562 human leukemia cells with 15 microM BHCNU for 1 h resulted in depletion of glutathione to 40% of control values, without significant reduction of cell viability. Subsequent treatment with 10 microM 4-hydroperoxycyclophosphamide (4-HC), a self-activating derivative of cyclophosphamide, reduced the level of glutathione to less than 20% of control values. BHCNU pretreatment enhanced the cytotoxicity of 4-HC resulting in a dose modification factor of 2.5. Alkaline elution analysis of cellular DNA demonstrated that the level of interstrand cross-linking was 2-fold higher in GSH-depleted cells than in nondepleted cells, and the induction of single strand breaks was markedly increased. These findings demonstrate that BHCNU potentiates the cytotoxicity of 4-HC and suggest that this is due to the increased formation of DNA interstrand cross-links caused by a reduced intracellular conjugation of 4-HC with glutathione which results in an increased binding of 4-HC to DNA targets.
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PMID:Depletion of cellular glutathione by N,N'-bis(trans-4-hydroxycyclohexyl)-N'-nitrosourea as a determinant of sensitivity of K562 human leukemia cells to 4-hydroperoxycyclophosphamide. 235 56

A study was made of the content of ubiquinone, vitamins A, E, ascorbic, dehydroascorbic and diketogulonic acids (DKGA), and malonic dialdehyde (MDA) in the liver, of the content of glutathione, the activity of superoxide dismutase (SOD) and glutathione reductase in red blood cells, of the content of vitamins A, E and ubiquinone in the spleen of C57Bl/6jG mice with inoculated leukemia La. It was found that in red blood cells of the animals with leukemia, the content of vitamin E and DKGA reduced, the MDA level increased, and the content of glutathione dropped whereas SOD activity rose. Application of the antioxidant complex of vitamins A, E, C appreciably improved the characteristics of enzymatic and non-enzymatic antioxidant protection of the liver and red blood cells of the leukemic animals without exerting any noticeable effect on the content of vitamin E and ubiquinone in the leukemic spleen tissue.
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PMID:[Use of the antioxidant complex of vitamins A, E and C in murine leukemia]. 258 50

In order to synthesize bifunctional antitumor compounds, the interaction of streptonigrin with [AuCl4]- has been studied. Using absorption, circular dichroism, and fluorescence measurements, we have shown that streptonigrin forms with Au(III) a 1:1 Au(III)-streptonigrin complex. This complex is very stable as long as gold is in the trivalent state and is able to inhibit glutathione reductase activity. In the presence of biological agents such as NADH and reduced glutathione, Au(III) is slowly reduced to Au(I) and removed from its binding site to streptonigrin. Original streptonigrin is thus recovered. This complex exhibits antitumor activity against P-388 leukemia which compares with that of the free drug.
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PMID:Bifunctional antitumor compounds: synthesis and characterization of a Au(III)-streptonigrin complex with thiol-modulating properties. 273 77

The inactivation of the enzyme glutathione reductase by 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) was studied in exponentially growing murine leukemia cells. A 1-hr incubation with 1.6 +/- 0.2 microM BCNU resulted in a 50% inhibition of glutathione reductase, while 10 microM BCNU caused total inhibition of the enzyme. The time required for 50% inhibition of glutathione reductase by 10 microM BCNU was 7 min. The recovery of glutathione reductase activity was studied by incubating cells with 10 microM BCNU for 30 min to inhibit all glutathione reductase activity, washing the cells free of drug, and continuing the incubation in fresh medium. Fifty percent of the activity returned within 12 hr. Glutathione reductase activity recovered normally when cell growth and DNA synthesis were inhibited in the cells, but it failed to recover when protein synthesis was inhibited. Therefore, the inactivation of glutathione reductase appears irreversible, and the recovery of enzymatic activity is dependent on the synthesis of new protein. Continuous incubation with 19.8 +/- 0.4 microM BCNU resulted in a 50% inhibition of cell growth. A 1-hr incubation with 7.3 +/- 0.8 microM BCNU resulted in a 50% loss of viability as measured by a soft agar clonogenic assay. These experiments quantify the inhibition of glutathione reductase by BCNU and the recovery of enzyme activity in the context of the toxic effects of the compound. A clinically useful inhibitor of glutathione reductase will require a wider difference between the concentrations required for enzyme inhibition and cytotoxicity than BCNU provides.
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PMID:Characterization of the inhibition of glutathione reductase and the recovery of enzyme activity in exponentially growing murine leukemia (L1210) cells treated with 1,3-bis(2-chloroethyl)-1-nitrosourea. 340 Dec 59

Selenium exists in a number of forms with differing valence states, some of which have shown antitumor activity. We studied the tumoricidal activity of four currently available selenium forms against a human leukemia cell line and exploited the differences among them to investigate the mechanism of antitumor action. Only selenocystine and sodium selenite showed antitumor activity, and these were also the only compounds which demonstrated significant redox chemistry, including depletion of cellular glutathione, stimulation of glutathione reductase, and stimulation of oxygen consumption. The interaction of these two compounds with glutathione suggests an intriguing potential role for them in cancer therapy.
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PMID:Selenium-induced cytotoxicity of human leukemia cells: interaction with reduced glutathione. 375 96

The activity of enzymatic defences against free radical attack including superoxide dismutase (SOD), catalase, glutathione peroxidase and glutathione reductase have been compared in some experimental animal tumours with the corresponding normal mouse tissues. The activity of SOD in PC6 plasmacytoma and P388 lymphocytic leukaemia was lower than in normal lymphocytes and the activity in a mouse bladder carcinoma (MB) was one-half of that of the normal bladder tissue. Similarly PC6, P388, TLX5 lymphoma and MB showed lower catalase activity than the corresponding normal tissues. The activity of glutathione peroxidase in tumours was in general comparable with that of the normal tissues with the exception of MB, while TLX5, PC6 and P388 contained much lower glutathione reductase activity than normal lymphocytes. The results suggest that it may be possible to selectively destroy certain tumours by peroxidative attack, and that P388 leukaemia would be much more sensitive than L1210 leukaemia to free radical production.
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PMID:Activities of free radical metabolizing enzymes in tumours. 686 May 48

The ectoenzyme gamma glutamyltransferase (GGT) a second messenger generating enzyme activity on the cytoplasmic membrane was biochemically analyzed in leukemic cells from patients with acute lymphoblastic and myeloid leukemias. The lower mean activity--0.594 IU/mg protein was noticed in patients with acute lymphoblastic leukemias (ALL), while the higher--0.956 IU/mg protein was found in acute myeloid leukemia patients (AML) in serum and 0.151 IU/mg protein in polymorphonuclear cells. The levels of the activity of glutathione reductase (GR) were increased but the activities of glutathione peroxidase (GSH Px) were significantly decreased in serum of leukemia patients.
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PMID:Activities of enzyme transducing extracellular signals--gamma glutamyltransferase and enzymes metabolizing glutathione in acute lymphoblastic and myeloid human leukemias. 761 77


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