Linked Life Data

16951200

Source:http://linkedlifedata.com/resource/pubmed/id/16951200

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
17
pubmed:dateCreated
2006-9-4
pubmed:abstractText
The thymidylate synthase inhibitor 5-fluorouracil (5-FU) continues to play a pivotal role in the treatment of cancer. A downstream event of thymidylate synthase inhibition involves the induction of a self-defeating base excision repair process. With the depletion of TTP pools, there is also an increase in dUMP. Metabolism of dUMP to the triphosphate dUTP results in elevated pools of this atypical precursor for DNA synthesis. Under these conditions, there is a destructive cycle of dUMP incorporation into DNA, removal of uracil by the base excision repair enzyme uracil-DNA glycosylase (UDG), and reincorporation of dUMP during the synthesis phase of DNA repair. The end point is DNA strand breaks and loss of DNA integrity, which contributes to cell death. Evidence presented here indicates that both the nuclear and the mitochondrial isoforms of UDG are modulated by FdUrd (and 5-FU) treatment in certain cell lines but not in others. Modulation occurs at the transcriptional and post-translational levels. Under normal conditions, nUDG protein appears in G(1) and is degraded during the S to G(2) phase transition. The present study provides evidence that, in certain cell lines, FdUrd mediates an atypical turnover of nUDG. Additional data indicate that, for cell lines that do not down-regulate nUDG, small interfering RNA-mediated knockdown of nUDG significantly increases resistance to the cytotoxic effects of FdUrd. Results from these studies show that nUDG is an additional determinant in FdUrd-mediated cytotoxicity and bolster the notion that the self-defeating base excision repair pathway, instigated by elevated dUTP (FdUTP) pools, contributes to the cytotoxic consequences of 5-FU chemotherapy.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1538-7445
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
66
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8829-37
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Fluorodeoxyuridine modulates cellular expression of the DNA base excision repair enzyme uracil-DNA glycosylase.
pubmed:affiliation
Department of Molecular Biology, School of Osteopathic Medicine and Graduate School of Biomedical Sciences, University of Medicine and Dentistry of New Jersey, Stratford, NJ 08084, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural