title: Cytokinetics and mechanism of action of AKO4: a novel nitrogen mustard targeted to bcr-abl.
abstract: The "combi-targeting" concept seeks to design molecules to not only block tyrosine kinase (TK) activity but also to induce DNA damage. Here we design AK04, a molecule that combines the pharmacophore chlorambucil with that of STI-571 (Gleevec). The results showed that although a less potent abl TK inhibitor than STI571, AK04 was capable of significantly blocking bcr-abl phosphorylation not only in a purified abl assay but also in the bcr-abl+ K562 cells. In contrast to STI571 and like chlorambucil, it induced a dose-dependent increase in DNA damage in these cells. More importantly, AK04 was 12-32-fold more potent than chlorambucil in all bcr-abl+ cells of our cell panel. In the isogenic human megakaryocytic Mo7e and Mo7/bcr-abl cells, AK04 selectively killed the bcr-abl transfectants. Flow cytometry revealed that despite being a five-fold less potent inhibitor of bcr-abl than STI-571, it induced a significant dose-dependent increase in levels of cell death by apoptosis in KU812 cells 24 h post-treatment. Under these conditions, chlorambucil did not induce any significant level of apoptosis. These results suggest that AK04 is a nitrogen mustard with binary bcr-abl/DNA targeting effects, a property that may account for its superior potency when compared with the classical mustard chlorambucil.
authors.affiliation: Cancer Drug Research Laboratory, Department of Medicine, Division of Medical Oncology, McGill University Health Center/Royal Victoria Hospital, 687 Pine Ave. West, M7.19, Montreal, Que., Canada H3A 1A1.
authors.forename: Athanasia
authors.initials: A
authors.lastname: Katsoulas
authors.forename: Zakaria
authors.initials: Z
authors.lastname: Rachid
authors.forename: Fouad
authors.initials: F
authors.lastname: Brahimi
authors.forename: James
authors.initials: J
authors.lastname: McNamee
authors.forename: Bertrand J
authors.initials: BJ
authors.lastname: Jean-Claude
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology; D018906:Antineoplastic Agents, Alkylating / Q000138:chemical synthesis / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D001549:Benzamides; D049109:Cell Proliferation / Q000187:drug effects; D002699:Chlorambucil / Q000494:pharmacology; D004249:DNA Damage / Q000187:drug effects; D005434:Flow Cytometry; D016044:Fusion Proteins, bcr-abl / Q000037:antagonists & inhibitors* / Q000235:genetics; D006801:Humans; D000068877:Imatinib Mesylate; D020014:K562 Cells / Q000187:drug effects; D007700:Kinetics; D008466:Mechlorethamine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000494:pharmacology*; D008533:Megakaryocytes / Q000187:drug effects; D010766:Phosphorylation / Q000187:drug effects; D010879:Piperazines / Q000494:pharmacology; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D011743:Pyrimidines / Q000494:pharmacology
chemical_list: C500928:AKO4 compound; D000970:Antineoplastic Agents; D018906:Antineoplastic Agents, Alkylating; D001549:Benzamides; D010879:Piperazines; D011743:Pyrimidines; D002699:Chlorambucil; D008466:Mechlorethamine; D000068877:Imatinib Mesylate; D011505:Protein-Tyrosine Kinases; D016044:Fusion Proteins, bcr-abl