Linked Life Data

17943230

Source:http://linkedlifedata.com/resource/pubmed/id/17943230

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2008-4-22
pubmed:abstractText
Clinically relevant resistance to the currently approved camptothecins, irinotecan and topotecan, is poorly understood but may involve increased expression of ATP-dependent drug transporters such as ABCG2 (breast cancer resistant protein, BCRP). Gimatecan (ST1481) is a lipophilic 7-substituted camptothecin derivative that exhibits potent anti-tumor activity in a variety of preclinical cancer models and is under investigation in the clinic. Previous studies reported that gimatecan cytotoxicity was not affected by expression of ABCG2. To confirm and extend this finding, we assessed the cytotoxicity of gimatecan in pairs of isogenic cell lines consisting of transfectants expressing either ABCG2 (including wild-type, R482T, or R482G mutants), ABCB1 (P-glycoprotein), ABCC1 (MRP1), ABCC2 (MRP2), or ABCC4 (MRP4). Expression of wild-type or mutant ABCG2 in human cell lines conferred resistance to topotecan but not to gimatecan. Similarly, intracellular accumulation of gimatecan was unaffected by expression of wild-type ABCG2. Furthermore, expression of P-glycoprotein or MRP2 did not alter gimatecan cytotoxicity. Whereas expression of MRP1 had a minor effect on gimatecan cytotoxicity, expression of ABCC4 was found to significantly reduce the anti-proliferative effects of this drug. Cells containing resistance-conferring mutations in topoisomerase I were also resistant to gimatecan. These results suggest that gimatecan may be more effective than irinotecan or topotecan in cancers that express ABCG2, but not in cancers that express high levels of ABCC4 or contain certain topoisomerase I (TOP1) mutations.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0167-6997
pubmed:author
pubmed:issnType
Print
pubmed:volume
26
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
205-13
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Effects of drug efflux proteins and topoisomerase I mutations on the camptothecin analogue gimatecan.
pubmed:affiliation
Department of Pharmacology, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, New Brunswick, NJ, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't