AP24163 inhibits the gatekeeper mutant of BCR-ABL and suppresses in vitro resistance.
Mutation in the ABL kinase domain is the principal mechanism of imatinib resistance in patients with chronic myelogenous leukaemia. The second generation BCR/ABL inhibitors nilotinib and dasatinib effectively inhibit most imatinib resistance variants, but are ineffective against the gatekeeper mutant, T315I. Gatekeeper mutation activates the kinase by stabilizing the hydrophobic spine. Here, we describe that the rationally designed compound AP24163 can inhibit native and gatekeeper mutants of the BCR/ABL kinase. Structural modelling suggests that AP24163 affects the flexibility of the P-loop and destabilizes the active conformation by disrupting the hydrophobic spine. In vitro screening for drug resistance identified clones with compound mutations involving both the P-loop and T315I. Our studies provide structural insights for the design of inhibitors against the gatekeeper mutant and suggest that up-front combination therapy may be required to prevent the emergence of compound-resistant mutations.
Azam
Mohammad
M
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, The Children's Hospital, Dana Farber Cancer Institute, Brigham and Women's Hospital, Boston, MA, USA.
Powers
John T
JT
Einhorn
William
W
Huang
Wei-Sheng
WS
Shakespeare
William C
WC
Zhu
Xiaotian
X
Dalgarno
David
D
Clackson
Tim
T
Sawyer
Tomi K
TK
Daley
George Q
GQ
D000225:Adenine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D001549:Benzamides / Q000737:chemistry* / Q000494:pharmacology; D001665:Binding Sites; D002460:Cell Line; D003198:Computer Simulation; D000069439:Dasatinib; D019008:Drug Resistance, Neoplasm; D016044:Fusion Proteins, bcr-abl / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D000068877:Imatinib Mesylate; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000188:drug therapy; D051379:Mice; D009154:Mutation; D010879:Piperazines / Q000737:chemistry / Q000494:pharmacology; D047428:Protein Kinase Inhibitors / Q000737:chemistry* / Q000494:pharmacology; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D011743:Pyrimidines / Q000737:chemistry / Q000494:pharmacology; D013844:Thiazoles / Q000737:chemistry / Q000494:pharmacology
C548138:AP 24163; D001549:Benzamides; D010879:Piperazines; D047428:Protein Kinase Inhibitors; D011743:Pyrimidines; D013844:Thiazoles; D000068877:Imatinib Mesylate; D011505:Protein-Tyrosine Kinases; D016044:Fusion Proteins, bcr-abl; C498826:nilotinib; D000225:Adenine; D000069439:Dasatinib