A new nonpeptidic inhibitor of 14-3-3 induces apoptotic cell death in chronic myeloid leukemia sensitive or resistant to imatinib

J Pharmacol Exp Ther. 2011 Mar;336(3):596-604. doi: 10.1124/jpet.110.172536. Epub 2010 Nov 1.

Abstract

Resistance of chronic myeloid leukemia (CML) to tyrosine kinase inhibitor imatinib mesylate (IM) is most often due to point mutations in the Bcr-Abl fusion gene. T315I mutation (resulting in substitution of Ile for a Thr residue at the "gatekeeper" position 315) raises particular concern, because it also provides resistance to second-generation kinase inhibitors already approved for clinical use (nilotinib and dasatinib). Much effort is therefore focused on alternative molecular-based strategies. Previous studies proved that binding to 14-3-3 scaffolding proteins leads to cytoplasmic compartmentalization and suppression of proapoptotic and antiproliferative signals associated with Bcr-Abl protein kinase, hence contributing to leukemic clone expansion. Here we investigated the effect of 14-3-3 inhibition disruption on hematopoietic cells expressing the IM-sensitive wild type Bcr-Abl and the IM-resistant T315I mutation. Using a virtual screening protocol and docking simulations, we identified a nonpeptidic inhibitor of 14-3-3, named BV02, that exhibits a remarkable cytotoxicity against both cell types. c-Abl release from 14-3-3σ, promoting its relocation to nuclear compartment (where it triggers transcription of p73-dependent proapoptotic genes) and to mitochondrial membranes (where it induces the loss of mitochondrial transmembrane potential) combined with c-Abl enhanced association with caspase 9 (a critical step of sequential caspase activation further contributing to c-Abl pro-apoptotic function) has a prominent role in the effect of BV02 on Bcr-Abl-expressing cells. In conclusion, BV02 may be considered as a treatment option for CML and, in particular, for more advanced phases of the disease that developed IM resistance as a consequence of Bcr-Abl point mutations.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 14-3-3 Proteins / antagonists & inhibitors*
  • 14-3-3 Proteins / chemistry
  • Amino Acid Sequence
  • Animals
  • Antineoplastic Agents / pharmacology
  • Apoptosis / drug effects*
  • Apoptosis / physiology
  • Benzamides / chemistry
  • Benzamides / pharmacology*
  • Benzamides / therapeutic use
  • Binding Sites / drug effects
  • Binding Sites / physiology
  • Cell Death / drug effects
  • Cell Death / physiology
  • Cell Line
  • Cell Line, Tumor
  • Crystallography, X-Ray
  • Drug Resistance, Neoplasm / physiology*
  • Humans
  • Imatinib Mesylate
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / drug therapy*
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / metabolism
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / pathology*
  • Mice
  • Molecular Sequence Data
  • Piperazines / pharmacology
  • Piperazines / therapeutic use*
  • Pyrazoles / chemistry
  • Pyrazoles / pharmacology*
  • Pyrazoles / therapeutic use
  • Pyrimidines / pharmacology
  • Pyrimidines / therapeutic use*

Substances

  • 14-3-3 Proteins
  • Antineoplastic Agents
  • BV02 compound
  • Benzamides
  • Piperazines
  • Pyrazoles
  • Pyrimidines
  • Imatinib Mesylate

Associated data

  • PDB/1YWT