Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2000-11-1
pubmed:abstractText
The property of forming crosslinks within DNA is seen as the major cause of the high carcinogenic, genotoxic and anti-neoplastic potency of bifunctional nitrogen mustards. To further investigate the importance for genotoxicity of a second reactive group in a molecule, the genetic activity profiles of the bifunctional nitrogen mustard mechlorethamine (MEC) and its monofunctional counterpart 2-chloroethylamine (CEA) were compared, using several in vivo end points in Drosophila. When post-meiotic male germ cells were alkylated by CEA and then transferred to nucleotide excision repair (NER)-proficient oocytes, no more than up to 4-fold increased forward mutation frequencies were induced. With oocytes deficient for XPG (DmXPG), frequencies were enhanced up to 50 times. For MEC mutation frequencies increased up to 40 times the background, whereas only a low hypermutability was observed when DmXPG were used instead of wild-type females, indicating that nitrogen mustard-induced monoadducts, in contrast to crosslinks, are efficiently repaired by the NER system. Specific locus mutations generated in the vermilion gene by CEA under NER(-) conditions were almost exclusively base pair substitutions (93%). The high proportion of mutations at guanine positions indicates a strong contribution of N7-alkylguanine to the mutational spectrum. MEC induced 64% deletions and other DNA rearrangements in crosses of males with DmXPG females. The small portion of point mutations (36%) was further reduced to approximately 20% with NER(+) females. Inactivation of NER had no potentiating effect on clastogenic events (chromosome loss) induced by CEA, which is in sharp contrast to the strongly enhanced forward mutation frequencies measured with DmXPG females. The weak genotoxic effectiveness of CEA under NER(+) conditions is clearly due to efficient error-free repair of monoalkyl adducts. These results further support the concept that bifunctional nitrogen mustards exert their mutagenic activity through formation of DNA crosslinks and that DNA monoadducts make only a minor contribution to their genotoxic activity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/2-chloroethylamine, http://linkedlifedata.com/resource/pubmed/chemical/Antineoplastic Agents, Alkylating, http://linkedlifedata.com/resource/pubmed/chemical/Cross-Linking Reagents, http://linkedlifedata.com/resource/pubmed/chemical/DNA, http://linkedlifedata.com/resource/pubmed/chemical/Drosophila Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Ethylamines, http://linkedlifedata.com/resource/pubmed/chemical/Eye Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Insect Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Mechlorethamine, http://linkedlifedata.com/resource/pubmed/chemical/Mutagens, http://linkedlifedata.com/resource/pubmed/chemical/Tryptophan Oxygenase, http://linkedlifedata.com/resource/pubmed/chemical/vermilion protein, Drosophila
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0143-3334
pubmed:author
pubmed:issnType
Print
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1859-67
pubmed:dateRevised
2010-7-23
pubmed:meshHeading
pubmed-meshheading:11023544-Animals, pubmed-meshheading:11023544-Antineoplastic Agents, Alkylating, pubmed-meshheading:11023544-Base Sequence, pubmed-meshheading:11023544-Cross-Linking Reagents, pubmed-meshheading:11023544-DNA, pubmed-meshheading:11023544-DNA Damage, pubmed-meshheading:11023544-DNA Mutational Analysis, pubmed-meshheading:11023544-DNA Repair, pubmed-meshheading:11023544-Drosophila, pubmed-meshheading:11023544-Drosophila Proteins, pubmed-meshheading:11023544-Ethylamines, pubmed-meshheading:11023544-Eye Color, pubmed-meshheading:11023544-Eye Proteins, pubmed-meshheading:11023544-Female, pubmed-meshheading:11023544-Genes, Lethal, pubmed-meshheading:11023544-Genes, Recessive, pubmed-meshheading:11023544-Insect Proteins, pubmed-meshheading:11023544-Male, pubmed-meshheading:11023544-Mechlorethamine, pubmed-meshheading:11023544-Mutagenicity Tests, pubmed-meshheading:11023544-Mutagens, pubmed-meshheading:11023544-Sequence Homology, pubmed-meshheading:11023544-Tryptophan Oxygenase
pubmed:year
2000
pubmed:articleTitle
The in vivo genetic activity profile of the monofunctional nitrogen mustard 2-chloroethylamine differs drastically from its bifunctional counterpart mechlorethamine.
pubmed:affiliation
Department of Radiation Genetics and Chemical Mutagenesis, MGC, Sylvius Laboratories, Leiden University Medical Centre, Wassenaarseweg 72, 2300 RA Leiden, The Netherlands.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't