title: CPI-0004Na, a new extracellularly tumor-activated prodrug of doxorubicin: in vivo toxicity, activity, and tissue distribution confirm tumor cell selectivity.
abstract: The search for cancer therapies that are more selective for tumor cells and spare normal sensitive cells has been very active for at least 20 years. The extracellularly tumor-activated peptidic prodrug of doxorubicin (Dox) CPI-0004Na (N-succinyl-beta-alanyl-L-leucyl-L-alanyl-L-leucyl-Dox) is potentially such a treatment. Here, we report the results of lethality studies performed with this compound in the mouse, showing that it is up to 4.6 times less toxic than Dox.HCl by the i.v. route and up to 16.2 times after i.p. administration. Pharmacokinetics and tissue distribution data indicate that this reduced toxicity is attributable to a lower uptake of Dox in normal tissues after treatment with CPI-0004Na than after the administration of an equimolar dose of Dox.HCl. For example, heart exposure to Dox is reduced >10-fold. Because of this reduced toxicity, higher doses of CPI-0004Na than of the parent drug could be used to treat nude mice bearing s.c. human breast (MCF-7/6) and colon (LS-174-T and CXF-280/10) tumors. In all three models, the prodrug showed a much improved efficacy as compared with Dox.HCl. Particularly, LS-174-T tumors that do not respond to Dox were inhibited by 68% after treatment with CPI-0004Na. Tissue distribution studies performed with MCF-7/6 tumor-bearing nude mice and comparing CPI-0004Na and Dox.HCl confirmed that the improved activity of the prodrug is actually the result of selective generation and uptake of Dox at the tumor site. Dox levels in tumor tissue were 2-fold higher after treatment with CPI-0004Na than after treatment with an equimolar dose of Dox.HCl, whereas normal tissue levels were reduced 1.4-29-fold.
authors.affiliation: Université Catholique de Louvain, Laboratory of Cell Biology, Place Croix du Sud 5, B-1348 Louvain-la-Neuve, Belgium.
authors.forename: Vincent
authors.initials: V
authors.lastname: Dubois
authors.forename: Luc
authors.initials: L
authors.lastname: Dasnois
authors.forename: Karim
authors.initials: K
authors.lastname: Lebtahi
authors.forename: Françoise
authors.initials: F
authors.lastname: Collot
authors.forename: Nathalie
authors.initials: N
authors.lastname: Heylen
authors.forename: Nathalie
authors.initials: N
authors.lastname: Havaux
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Fernandez
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Lobl
authors.forename: Cecilia
authors.initials: C
authors.lastname: Oliyai
authors.forename: Matthew
authors.initials: M
authors.lastname: Nieder
authors.forename: Dan
authors.initials: D
authors.lastname: Shochat
authors.forename: Geoffrey T
authors.initials: GT
authors.lastname: Yarranton
authors.forename: André
authors.initials: A
authors.lastname: Trouet
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000633:toxicity; D001943:Breast Neoplasms / Q000188:drug therapy / Q000378:metabolism; D004317:Doxorubicin / Q000031:analogs & derivatives / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000633:toxicity; D005260:Female; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009842:Oligopeptides / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000633:toxicity; D011355:Prodrugs / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000633:toxicity; D014018:Tissue Distribution; D023041:Xenograft Model Antitumor Assays
chemical_list: D000970:Antineoplastic Agents; C438951:N-(succinyl-beta-alanyl-L-leucyl-L-alanyl-L-leucyl)doxorubicin; D009842:Oligopeptides; D011355:Prodrugs; D004317:Doxorubicin