Antileukemic effects of the novel, mutant FLT3 inhibitor NVP-AST487: effects on PKC412-sensitive and -resistant FLT3-expressing cells.

Abstract

An attractive target for therapeutic intervention is constitutively activated, mutant FLT3, which is expressed in a subpopulation of patients with acute myelocyic leukemia (AML) and is generally a poor prognostic indicator in patients under the age of 65 years. PKC412 is one of several mutant FLT3 inhibitors that is undergoing clinical testing, and which is currently in late-stage clinical trials. However, the discovery of drug-resistant leukemic blast cells in PKC412-treated patients with AML has prompted the search for novel, structurally diverse FLT3 inhibitors that could be alternatively used to override drug resistance. Here, we report the potent and selective antiproliferative effects of the novel mutant FLT3 inhibitor NVP-AST487 on primary patient cells and cell lines expressing FLT3-ITD or FLT3 kinase domain point mutants. NVP-AST487, which selectively targets mutant FLT3 protein kinase activity, is also shown to override PKC412 resistance in vitro, and has significant antileukemic activity in an in vivo model of FLT3-ITD(+) leukemia. Finally, the combination of NVP-AST487 with standard chemotherapeutic agents leads to enhanced inhibition of proliferation of mutant FLT3-expressing cells. Thus, we present a novel class of FLT3 inhibitors that displays high selectivity and potency toward FLT3 as a molecular target, and which could potentially be used to override drug resistance in AML.

• Authors: Ellen Weisberg, Johannes Roesel, Guido Bold, Pascal Furet, Jingrui Jiang, Jan Cools, Renee D Wright, Erik Nelson, Rosemary Barrett, Arghya Ray, Daisy Moreno, Elizabeth Hall-Meyers, Richard Stone, Ilene Galinsky, Edward Fox, Gary Gilliland, John F Daley, Suzan Lazo-Kallanian, Andrew L Kung, James D Griffin
• Journal: Blood (Blood) Vol. 112 Issue 13 Pg. 5161-70 (Dec 15 2008) ISSN: 1528-0020 [Electronic] United States
• PMID: 18820131 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents
• Carbanilides
• Mutant Proteins
• NVP-AST487
• Protein Kinase Inhibitors
• FLT3 protein, human
• fms-Like Tyrosine Kinase 3
• Protein Kinase C
• Staurosporine
• midostaurin

Topics

• Animals
• Antineoplastic Agents (pharmacology)
• Antineoplastic Combined Chemotherapy Protocols (pharmacology)
• Carbanilides (pharmacology)
• Cell Line
• Drug Resistance, Neoplasm
• Leukemia, Myeloid, Acute (drug therapy)
• Mice
• Mutant Proteins (antagonists & inhibitors)
• Protein Kinase C (antagonists & inhibitors)
• Protein Kinase Inhibitors (pharmacology)
• Staurosporine (analogs & derivatives)
• fms-Like Tyrosine Kinase 3 (antagonists & inhibitors)