title: In vitro activity of novel dual action MDR anthranilamide modulators with inhibitory activity on CYP-450 (Part 2).
abstract: Synthesis and in vitro cytotoxicity assays of new anthranilamide MDR modulators have been performed to assess their inhibition potency on the P-glycoprotein (P-gp) transporter. Previous studies showed that the replacement of the aromatic spacer group between nitrogen atoms (N(1) and N(2)) in the P-gp inhibitor XR9576 with ethyl or propyl chain is optimal for P-gp inhibition potency. To confirm that observation, the ethyl or the propyl linker arm was replaced with a pyrrolidine or an alicyclic group such as cyclohexyl. In addition, an arylpiperazinyl group and two methoxyl groups onto the anthranilic part were introduced to assess their effect on the anti P-gp activity. Five molecules were prepared and evaluated on CEM/VLB500. All new anthranilamides were more potent than verapamil, most of them exhibited a lower cytotoxicity than XR9576. Compound 5 was the most potent and its inhibition activity was similar to XR9576. Interestingly, in vitro biotransformation studies of compounds 4 and 5 using human CYP-450 isoforms revealed, that conversely to XR9576, compounds 4 and 5 inhibited CYP3A4, an enzyme that colocalizes with P-gp in the intestine and contributes to tumor cell chemoresistance by enhancing the biodisposition of numerous drugs, notably paclitaxel. In that context, 5 might be suitable for further drug development.
authors.affiliation: Instituts des Biomatériaux et des Biotechnologies, Hôpital St.-François d'Assise, Université Laval, Que., Canada G1L 3L5. plabrie16@hotmail.com
authors.forename: Philippe
authors.initials: P
authors.lastname: Labrie
authors.forename: Shawn P
authors.initials: SP
authors.lastname: Maddaford
authors.forename: Jacques
authors.initials: J
authors.lastname: Lacroix
authors.forename: Concettina
authors.initials: C
authors.lastname: Catalano
authors.forename: David K H
authors.initials: DK
authors.lastname: Lee
authors.forename: Suman
authors.initials: S
authors.lastname: Rakhit
authors.forename: René C
authors.initials: RC
authors.lastname: Gaudreault
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000032:analysis / Q000037:antagonists & inhibitors*; D001681:Biological Assay; D045744:Cell Line, Tumor; D051544:Cytochrome P-450 CYP3A; D065607:Cytochrome P-450 Enzyme Inhibitors; D003577:Cytochrome P-450 Enzyme System / Q000032:analysis; D018432:Drug Resistance, Multiple / Q000187:drug effects*; D019008:Drug Resistance, Neoplasm / Q000187:drug effects*; D006801:Humans; D007422:Intestines / Q000201:enzymology; D011719:Pyrazines / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D011804:Quinolines / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D062367:ortho-Aminobenzoates / Q000737:chemistry
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D065607:Cytochrome P-450 Enzyme Inhibitors; D011719:Pyrazines; D011804:Quinolines; D062367:ortho-Aminobenzoates; D003577:Cytochrome P-450 Enzyme System; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human; C402343:tariquidar; C000219:anthranilamide