Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
2004-10-19
pubmed:abstractText
As a single agent the ERBB1 inhibitor, gefitinib (Iressa; ZD1839) showed minimal activity against a panel of 10 pediatric tumor xenografts that do not express the ERBB1 receptor. However, combined with irinotecan (CPT-11), significantly greater than additive activity was observed in four of eight models (P < 0.05), and the combination showed enhanced activity against three additional tumor lines. Breast cancer resistance protein (ABCG2), a transporter that confers resistance to SN-38 (the active metabolite of irinotecan), was readily detected in six of nine xenograft models examined by immunohistochemistry. In vitro gefitinib potently reversed resistance to SN-38 only in a cell line that overexpressed functional ABCG2. However, overexpression of ABCG2 did not decrease accumulation nor increase the rate of efflux of [(14)C]gefitinib. On the basis of these results and the distribution of Abcg2 in mouse tissues, we assessed the ability of gefitinib to modulate irinotecan pharmacokinetics. Oral gefitinib coadministration resulted in no change in clearance of intravenously administered irinotecan. However, gefitinib treatment dramatically increased the oral bioavailability of irinotecan after simultaneous oral administration. It is concluded that gefitinib may modulate SN-38 activity at the cellular level to reverse tumor resistance mediated by ABCG2 through inhibiting drug efflux and may be used potentially in humans to modulate the oral bioavailability of a poorly absorbed camptothecin such as irinotecan.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
64
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7491-9
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:15492275-ATP-Binding Cassette Transporters, pubmed-meshheading:15492275-Administration, Oral, pubmed-meshheading:15492275-Animals, pubmed-meshheading:15492275-Antineoplastic Combined Chemotherapy Protocols, pubmed-meshheading:15492275-Biological Availability, pubmed-meshheading:15492275-Bone Neoplasms, pubmed-meshheading:15492275-Camptothecin, pubmed-meshheading:15492275-Cell Line, Tumor, pubmed-meshheading:15492275-Drug Synergism, pubmed-meshheading:15492275-Female, pubmed-meshheading:15492275-Humans, pubmed-meshheading:15492275-Mice, pubmed-meshheading:15492275-Mice, Inbred ICR, pubmed-meshheading:15492275-Mice, SCID, pubmed-meshheading:15492275-Neoplasm Proteins, pubmed-meshheading:15492275-Osteosarcoma, pubmed-meshheading:15492275-Quinazolines, pubmed-meshheading:15492275-Receptor, Epidermal Growth Factor, pubmed-meshheading:15492275-Xenograft Model Antitumor Assays
pubmed:year
2004
pubmed:articleTitle
Gefitinib enhances the antitumor activity and oral bioavailability of irinotecan in mice.
pubmed:affiliation
Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't