Linked Life Data

16818517

Source:http://linkedlifedata.com/resource/pubmed/id/16818517

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2006-7-4
pubmed:abstractText
Enzyme-prodrug approaches to cancer therapy, theoretically, have the potential to mediate tumor-selective cytotoxicity. However, even if tumor-specific prodrug activation is achieved, enzyme-prodrug systems investigated thus far comprised a single enzyme and a specific prodrug. Although targeted, such systems constitute single-agent therapy, which may be ineffective and/or may promote development of drug resistance. Therefore, a goal of our laboratories was to design and characterize a novel dipiperidinyl derivative of etoposide [1,4'-dipiperidine-1'-carboxylate-etoposide (dp-VP16)] that would act as a prodrug. We envisioned that dp-VP16 would be converted to the active chemotherapeutic agent VP-16 by the same rabbit carboxylesterase (rCE) that we have previously shown to efficiently activate the prodrug irinotecan (CPT-11). This dp-VP16 prodrug might then be used in combination with CPT-11, with both drugs activated by a single enzyme. We evaluated the ability of pure rCE and two human carboxylesterases, hCE1 and hiCE (hCE2), to activate dp-VP16 in vitro, and in neuroblastoma cell lines designed to express/overexpress each enzyme. In SK-N-AS neuroblastoma cell transfectants, expression of rCE or hiCE decreased the IC50 of dp-VP16 as a single agent by 8.3- and 3.4-fold, respectively, in growth inhibition assays. Purified hCE1 did not metabolize dp-VP16 in vitro and did not affect its IC50 in intact cells. The combination indices of sequential exposure to CPT-11 followed by dp-VP16 ranged from approximately 0.4 to 0.6, suggesting that this combination produced greater-than-additive cytotoxicity in neuroblastoma cells expressing rCE. These data provide proof-of-principle that enzyme-prodrug therapy approaches comprised of prodrugs with complementary mechanisms of cytotoxicity that are activated by a single enzyme can be developed.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1535-7163
pubmed:author
pubmed:issnType
Print
pubmed:volume
5
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1577-84
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Development of an etoposide prodrug for dual prodrug-enzyme antitumor therapy.
pubmed:affiliation
Department of Molecular Pharmacology, St. Jude Children's Research Hospital, 332 North Lauderdale, Memphis, TN 38105, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural