|
|
Blood, 1 October 2006, Vol. 108, No. 7, pp. 2332-2338.
Prepublished online as a Blood First Edition Paper on June 13, 2006; DOI 10.1182/blood-2006-02-004580.
Previous Article | Next Article 
Submitted February 24, 2006
Accepted May 5, 2006
Comparison of imatinib, dasatinib (BMS-354825), and nilotinib (AMN107) in an n-ethyl-n-nitrosourea (ENU)-based mutagenesis screen: high efficacy of drug combinations
Heather A. Bradeen, Christopher A. Eide, Thomas O'Hare, Kara J. Johnson, Stephanie G. Willis, Francis Y. Lee, Brian J. Druker, and Michael W Deininger*
Oregon Health&Science University
Bristol-Myers Squibb
HHMI/Oregon Health & Science University
Oregon Health and Science University
* Corresponding author; email: deininge{at}ohsu.edu.
BMS-354825 (dasatinib) and AMN107 (nilotinib) are potent alternate Abl inhibitors with activity against many imatinib resistant BCR-ABL kinase domain (KD) mutants, except T315I. We used N-ethyl-N-nitrosourea (ENU)-exposed Ba/F3-p210BCR-ABL cells to compare incidence and types of KD mutants emerging in the presence of imatinib, dasatinib and nilotinib, alone and in dual combinations. Although ENU is expected to induce mutations in multiple proteins, resistant clones were almost exclusively BCR-ABL KD mutant at relevant concentrations of nilotinib and dasatinib, consistent with a central role of KD mutations for resistance to these drugs. Twenty different mutations were identified with imatinib, 10 with nilotinib (including only one novel mutation, E292V), and 9 with dasatinib. At intermediate drug levels the spectrum narrowed to F317V and T315I for dasatinib and Y253H, E255V, and T315I for nilotinib. Thus, cross resistance is limited to T315I, which is also the only mutant isolated at drug concentrations equivalent to maximal achievable plasma trough levels. With drug combinations maximal suppression of resistant clone outgrowth was achieved at lower concentrations compared to single agents, suggesting that such combinations may be equipotent to higher dose single agents. However, sequencing uniformly revealed T315I, consistent with the need for a T315I inhibitor to completely block resistance.

CiteULike Connotea Del.icio.us Digg Reddit Technorati What's this?
Related Articles in Blood Online:
-
MEK1/2 inhibitors sensitize Bcr/Abl+ human leukemia cells to the dual Abl/Src inhibitor BMS-354/825
- Tri K. Nguyen, Mohamed Rahmani, Hisashi Harada, Paul Dent, and Steven Grant
Blood 2007 109: 4006-4015.
[Abstract]
[Full Text]
[PDF]
-
Beneficial effects of combining nilotinib and imatinib in preclinical models of BCR-ABL+ leukemias
- Ellen Weisberg, Laurie Catley, Renee D. Wright, Daisy Moreno, Lolita Banerji, Arghya Ray, Paul W. Manley, Juergen Mestan, Doriano Fabbro, Jingrui Jiang, Elizabeth Hall-Meyers, Linda Callahan, Jamie L. DellaGatta, Andrew L. Kung, and James D. Griffin
Blood 2007 109: 2112-2120.
[Abstract]
[Full Text]
[PDF]
|
|