0000000000422403

AUTHOR

Manfred Wiessler

showing 5 related works from this author

ChemInform Abstract: Synthesis of 2-Amino-6-(2- [18F] fluoro-pyridine-4-ylmethoxy)-9-(octyl-β-D-glucosyl)-purine: A Novel Radioligand for Positron Em…

2010

Purinemedicine.diagnostic_testO6-methylguanineChemistryGeneral MedicineDNA methyltransferaseTumor tissuechemistry.chemical_compoundBiochemistryPositron emission tomographyPyridinemedicineRadioligandNucleic acidChemInform
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Establishment and functional validation of a structural homology model for human DNA methyltransferase 1

2003

Changes in DNA methylation patterns play an important role in tumorigenesis. The DNA methyltransferase 1 (DNMT1) protein represents a major DNA methyltransferase activity in human cells and is therefore a prominent target for experimental cancer therapies. However, there are only few available inhibitors and their high toxicity and low specificity have so far precluded their broad use in chemotherapy. Based on the strong conservation of catalytic DNA methyltransferase domains we have used a homology modeling approach to determine the three-dimensional structure of the DNMT1 catalytic domain. Our results suggest an overall structural conservation with other DNA methyltransferases but also in…

DNA (Cytosine-5-)-Methyltransferase 1Models MolecularMethyltransferaseMolecular Sequence DataBiophysicsDNA Methyltransferase InhibitorComputational biologyBiologymedicine.disease_causeModels BiologicalBiochemistryDNA methyltransferasechemistry.chemical_compoundCatalytic DomainTumor Cells CulturedmedicineHumansAmino Acid SequenceDNA (Cytosine-5-)-MethyltransferasesHomology modelingEnzyme InhibitorsMolecular BiologyGeneticsSequence Homology Amino AcidCell BiologyDNA MethylationModels ChemicalchemistryDNA methylationAzacitidineDNMT1Nucleic Acid ConformationCarcinogenesisDNABiochemical and Biophysical Research Communications
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Inactivation of O(6)-methylguanine-DNA methyltransferase by glucose-conjugated inhibitors.

2001

The DNA-repair protein O6-methylguanine-DNA methyltransferase (MGMT) is a decisive determinant of resistance of tumor cells to methylating and chloroethylating anti-cancer drugs. Therefore, selective inhibition of MGMT in tumors is expected to cause tumor sensitization. Several inhibitors of MGMT have been developed which function in both tumors and normal tissue. To deplete MGMT preferentially in tumors, strategies to target the inhibitor to the tumor tissue need to be developed. Here, we report on the properties of glucose-conjugated MGMT inhibitors that might be useful for tumor targeting since tumor cells frequently over-express glucose transporter. O6-Benzylguanine (O6BG), 8-aza-O6-ben…

Cancer ResearchMethyltransferaseGuaninebiologyDNA repairGlucose transporterbiology.organism_classificationDNA methyltransferaseMolecular biologydigestive system diseasesHeLaO(6)-Methylguanine-DNA MethyltransferaseGlucoseOncologyTargeted drug deliveryEnzyme inhibitorbiology.proteinTumor Cells CulturedHumansEnzyme InhibitorsneoplasmsAlkyltransferaseHeLa CellsInternational journal of cancer
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Induction of DNA breaks and apoptosis in crosslink-hypersensitive V79 cells by the cytostatic drug beta-D-glucosyl-ifosfamide mustard.

2001

To study molecular aspects of cytotoxicity of the anticancer drug β-D-glucose-ifosfamide mustard we investigated the potential of the agent to induce apoptosis and DNA breakage. Since β-D-glucose-ifosfamide mustard generates DNA interstrand crosslinks, we used as an in vitro model system a pair of isogenic Chinese hamster V79 cells differing in their sensitivity to crosslinking agents. CL-V5B cells are dramatically more sensitive (30-fold based on D10 values) to the cytotoxic effects of β-D-glucose-ifosfamide mustard as compared to parental V79B cells. After 48 h of pulse-treatment with the agent, sensitive cells but not the resistant parental line undergo apoptosis and necrosis, with apopt…

Cancer ResearchProgrammed cell deathNecrosisDNA damageDNA repairAntineoplastic AgentsBiologychemistry.chemical_compoundCricetinaemedicineCytotoxic T cellAnimalsExperimental TherapeuticsIfosfamideDNA breaksCytotoxicityapoptosisDNAPhosphoramide MustardMolecular biologyNitrogen mustardEnzyme ActivationCross-Linking ReagentsGlucoseOncologyBiochemistrychemistryApoptosisCaspasescancer therapyPhosphoramide Mustardscyclophosphamidemedicine.symptomDNA DamageBritish journal of cancer
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Determination of DNA single strand breaks and selective DNA amplification by N-nitrodimethylamine and analogs, and estimation of the indicator cells'…

1986

N-nitrodimethylamine is metabolized oxidatively to N-nitrohydroxymethylmethylamine, which decomposes to yield formaldehyde and N-nitromethylamine. All four compounds and N-nitromethylamine were tested for their ability to induce DNA single strand breaks in hepatocytes and in SV 40-transformed Chinese hamster embryo cell lines. Only the two monoalkylnitramines were positive. They induced single strand breaks in hepatocytes, but were not effective in the other cells. Formaldehyde and N-nitrohydroxymethylmethylamine were toxic to the cells. None of the compounds tested was able to induce selective DNA amplification in the two transformed cell lines. Enzymes involved in drug metabolism were ass…

DNA ReplicationCancer ResearchHamsterDNA Single-StrandedSimian virus 40BiologyChinese hamsterCell Linechemistry.chemical_compoundCricetulusCricetinaeFormaldehydeAnimalsEpoxide hydrolaseCells Culturedchemistry.chemical_classificationDose-Response Relationship DrugDNA replicationGene AmplificationGeneral Medicinebiology.organism_classificationCell Transformation ViralEmbryo MammalianRatsEnzymeOncologychemistryBiochemistryLiverCell cultureDrug metabolismDNADimethylaminesJournal of cancer research and clinical oncology
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