Linked Life Data

8691469

Source:http://linkedlifedata.com/resource/pubmed/id/8691469

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1996-8-26
pubmed:abstractText
We report here the synthesis and biological evaluation of novel DNA topoisomerase II inhibitors, podophenazine (8), 2'',3'' "-dichloropodophenazine (9), and benzopodophenazine (10), and their 4beta-p-nitroaniline derivatives 13-15. Among these, 4'-0-demethyl-4beta-(4'''- nitroanilino)-4-desoxypodophenazine (13) and 4'-O-demethyl-2'',3''-dichloro-4beta-(4-'''-nitroanilino)-4- desoxypodophenazine (14) were found to inhibit KB cells at sub-micromolar concentrations (IC50 = 0.11 +/- 0.03 and 0.48 +/- 0.17 microM, respectively. Against KB/7d cells (a pleiotrophic multiple drug-resistant subclone selected with etoposide which has reduced level of topoisomerase II), only compound 13 out of a target series maintained activity in the sub-micromolar concentration range with a IC 50 value of 0.56 +/- 0.13 mu M. The differential toxicity ratio for 13 [IC 50 (KB/7d)/IC 50 (KB)] was approximately 5. Unlike etoposide and its congeners, compounds 13 and 14 were found to be weak inhibitors of the catalytic activity of topoisomerase II (IC100 = > 100 and > 150 microM, respectively). In vitro protein-linked DNA complex formation assay revealed that 13 and 14, respectively, induced marginal response (13 at 1 microM, 320.3 +/- 124.5 cpm; 13 at 50 microM, 308.8 +/- 139.9 cpm; 13 at 100 mu M, 446.0 +/- 153.5 cpm) and no response (14 at 1 microM, 104.9 +/- 52.6 cpm; 14 at 50 microM, 103.3 +/- 42.6 cpm; 14 at 100 microM, 101.4 +/- 35.2 cpm) compared to the enzyme control. On the basis of these results, we conclude that the mechanism of enzyme inhibition of these compounds is distinct from that of etoposide and its congeners. We are currently investigating the mechanism(s) of action of compounds 13 and 14 as well as synthesizing other derivatives in order to better characterize structure-activity relationships of this series of compounds.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0022-2623
pubmed:author
pubmed:issnType
Print
pubmed:day
29
pubmed:volume
39
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1396-402
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Antitumor agents. 164. Podophenazine, 2'',3''-dichloropodophenazine, benzopodophenazine, and their 4 beta-p-nitroaniline derivatives as novel DNA topoisomerase II inhibitors.
pubmed:affiliation
Division of Medicinal Chemistry and Natural Products, School of Pharmacy, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't