Linked Life Data

2909741

Source:http://linkedlifedata.com/resource/pubmed/id/2909741

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1989-2-6
pubmed:abstractText
The mechanism of cytotoxicity of a series of 4-substituted derivatives of 9-[[3-(dimethylamino)propyl]amino]-1-nitroacridine (nitracrine) has been studied, using a panel of DNA repair-defective mutants of the Chinese hamster ovary cell line AA8. Cell lines UV-4 and UV-5 were hypersensitive to nitracrine, with sensitivities approximately 10-fold greater than that of AA8, while EM-9 showed a hypersensitivity factor (HF) of about 2-fold. This pattern suggests the major cytotoxic lesions induced by nitracrine are bulky DNA monoadducts, rather than DNA interstrand cross-links as previously suggested. The desnitro analogue of nitracrine, which retains the intercalative potential of the latter but cannot be metabolically activated by nitro reduction, showed no hypersensitivity, indicating the specificity with which this panel of cell lines can discriminate different types of DNA damage. Several of the highly cytotoxic 4-substituted nitracrine derivatives showed HFs similar to that of the parent, but the less potent 4-dialkylamino and 4-COOMe derivatives showed much lower HFs for UV-4, suggesting that different mechanisms of cytotoxicity contribute. All compounds showed similar HFs under both aerobic and hypoxic conditions, indicating that hypoxia-selective toxicity in this series is due to a quantitative rather than qualitative change in the presence of oxygen. Rates of metabolic consumption of the compounds were measured under both aerobic and hypoxic conditions by bioassay against the sensitive UV-4 cell line. The results agreed well with previous inferences on metabolic stability derived from cell-killing kinetics and showed that electron-donating 4-substituents can be used to increase metabolic stability in vitro. Such stabilization may enhance the therapeutic utility of the nitroacridines in cancer therapy since rapid metabolism of nitracrine appears to prevent its activity against hypoxic cells in solid tumors.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0022-2623
pubmed:author
pubmed:issnType
Print
pubmed:volume
32
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
31-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Hypoxia-selective antitumor agents. 2. Electronic effects of 4-substituents on the mechanisms of cytotoxicity and metabolic stability of nitracrine derivatives.
pubmed:affiliation
Department of Pathology, University of Auckland School of Medicine, New Zealand.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't