Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1998-2-24
pubmed:abstractText
Mitomycin C (MMC) is a DNA cross-linking agent that has been used in cancer chemotherapy for over 20 years, yet little is known either qualitatively or quantitatively about MMC-induced DNA adduct formation and repair in vivo. As an initial means of investigating this, we used a recently developed 32P-postlabeling assay to examine the formation and loss of MMC-DNA adducts in the tissues of a simple in vivo model test system, the chick embryo, following treatment with a chemotherapeutic dose of MMC. As early as 15 min after MMC treatment, four adducts could be detected in the liver which were tentatively identified as the (CpG) N2G-MMC-N2G interstrand cross-link, the bifunctionally activated MMC-N2G monoadduct, and two isomers (alpha and beta) of the monofunctionally activated MMC-N2G monoadduct. The (GpG) N2G-MMC-N2G intrastrand cross-link appears to be a poor substrate for nuclease P1 and/or T4 kinase and was not evaluable by this assay. Levels of all four detectable adducts increased substantially within the first 2 h after MMC treatment, reached maximal levels by 6 h, and decreased progressively thereafter through 24 h, although low levels of certain adducts persisted beyond 24 h. Lung and kidney had comparable levels of total MMC adducts, which were approximately 60% those of the liver, and there were no significant differences in the proportion of specific adducts among the three tissues. The interstrand cross-link represented approximately 13-14% of the total MMC adducts, which is approximately 5-fold greater than the proportion of CpG sites in the genome. In addition, the interstrand cross-link was selectively decreased after 16 h relative to the three monoadducts, suggesting preferential repair. The effect of modulating different components of the Phase I and Phase II drug metabolism on MMC adduct formation, using either glutethimide, 3,4,3',4'-tetrachlorobiphenyl, dexamethasone, buthionine sulfoximine, ethacrynic acid, or N-acetylcysteine pretreatments, was examined to characterize the possible pathways of MMC metabolism and adduct formation in vivo. Surprisingly, none of these pretreatments had a significant effect on individual or total adducts with the exception of dexamethasone, which caused an almost 2-fold proportional increase in all four adducts in the liver.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/3,4,3',4'-tetrachlorobiphenyl, http://linkedlifedata.com/resource/pubmed/chemical/Acetylcysteine, http://linkedlifedata.com/resource/pubmed/chemical/Buthionine Sulfoximine, http://linkedlifedata.com/resource/pubmed/chemical/Cross-Linking Reagents, http://linkedlifedata.com/resource/pubmed/chemical/DNA, http://linkedlifedata.com/resource/pubmed/chemical/DNA Adducts, http://linkedlifedata.com/resource/pubmed/chemical/Dexamethasone, http://linkedlifedata.com/resource/pubmed/chemical/Ethacrynic Acid, http://linkedlifedata.com/resource/pubmed/chemical/Glutathione, http://linkedlifedata.com/resource/pubmed/chemical/Glutethimide, http://linkedlifedata.com/resource/pubmed/chemical/Mitomycin, http://linkedlifedata.com/resource/pubmed/chemical/Phosphorus Radioisotopes, http://linkedlifedata.com/resource/pubmed/chemical/Polychlorinated Biphenyls
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
58
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
453-61
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:9458089-Acetylcysteine, pubmed-meshheading:9458089-Animals, pubmed-meshheading:9458089-Biotransformation, pubmed-meshheading:9458089-Buthionine Sulfoximine, pubmed-meshheading:9458089-Chick Embryo, pubmed-meshheading:9458089-Cross-Linking Reagents, pubmed-meshheading:9458089-DNA, pubmed-meshheading:9458089-DNA Adducts, pubmed-meshheading:9458089-DNA Damage, pubmed-meshheading:9458089-DNA Repair, pubmed-meshheading:9458089-Dexamethasone, pubmed-meshheading:9458089-Enzyme Induction, pubmed-meshheading:9458089-Ethacrynic Acid, pubmed-meshheading:9458089-Glutathione, pubmed-meshheading:9458089-Glutethimide, pubmed-meshheading:9458089-Kidney, pubmed-meshheading:9458089-Liver, pubmed-meshheading:9458089-Lung, pubmed-meshheading:9458089-Metabolic Detoxication, Drug, pubmed-meshheading:9458089-Mitomycin, pubmed-meshheading:9458089-Phosphorus Radioisotopes, pubmed-meshheading:9458089-Polychlorinated Biphenyls, pubmed-meshheading:9458089-Time Factors
pubmed:year
1998
pubmed:articleTitle
Detection of mitomycin C-DNA adducts in vivo by 32P-postlabeling: time course for formation and removal of adducts and biochemical modulation.
pubmed:affiliation
Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755-3564, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't