HOXA10 expression induced by Abl kinase inhibitors enhanced apoptosis through PI3K pathway in CML cells

Leuk Res. 2008 Jun;32(6):962-71. doi: 10.1016/j.leukres.2007.11.034. Epub 2008 Jan 10.

Abstract

Chronic myelogenous leukemia is characterized by the reciprocal chromosomal translocation (9;22), which generates a novel fusion gene, BCR-ABL. Bcr-Abl-expressing leukemia cells are highly resistant to apoptosis. Imatinib an Abl kinase inhibitor, is a highly effective agent for patients with CML. However, a small percentage of these patients and most advanced-phase patients relapse on imatinib therapy. It is poorly understood whether the Abl kinase inhibitors are able to eradicate CML progenitor or stem cells. In this study, we investigated the role of HOXA10 in CML cell lines and the hematopoietic progenitor cells derived from CML patients, and whether the regulation of HOXA10 eradicates Bcr-Abl(+) hematopoietic stem/progenitor cells. The Abl kinase inhibitors and PI3K inhibitor, LY294002, induced the expression of HOXA10, and it enhanced apoptosis in CML cells. Moreover, the reduction of HOXA10 expression by siRNA in CML cells inhibited apoptosis by treatment with the Abl kinase inhibitors and LY294002. These results revealed that HOXA10 had an important role in induction of apoptosis by the Abl kinase inhibitors in CML cells. Finally, we showed that the inhibition of HOXA10 expression by siRNA increased the numbers of CFU-GEMM, BFU-E, and CFU-GM when the cells were treated with the combination of BMS354825 and LY294002 compared to control cells, and HOXA10 played a critical role in the committed colony-formation in CML. This study shows for the first time that the Abl kinase inhibitor and LY294002 induced HOXA10, and HOXA10 had an important role in apoptosis or cell growth inhibition in CML cells in vitro.

Publication types

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

MeSH terms

  • Adult
  • Apoptosis / drug effects*
  • Benzamides
  • Blotting, Western
  • Bone Marrow
  • Case-Control Studies
  • Cell Cycle / drug effects
  • Cell Proliferation / drug effects
  • Cells, Cultured
  • Chromones / pharmacology
  • Colony-Forming Units Assay
  • DNA Primers
  • Dasatinib
  • Female
  • Fluorescent Antibody Technique
  • Gene Expression Regulation, Neoplastic / drug effects
  • Hematopoietic Stem Cells / drug effects
  • Homeobox A10 Proteins
  • Homeodomain Proteins / antagonists & inhibitors
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / metabolism*
  • Humans
  • Imatinib Mesylate
  • K562 Cells
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / drug therapy
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / metabolism*
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / pathology
  • Male
  • Middle Aged
  • Morpholines / pharmacology
  • Phosphatidylinositol 3-Kinases / metabolism*
  • Phosphoinositide-3 Kinase Inhibitors
  • Piperazines
  • Protein Kinase Inhibitors / pharmacology*
  • Proto-Oncogene Proteins c-abl / antagonists & inhibitors*
  • Proto-Oncogene Proteins c-abl / genetics
  • Proto-Oncogene Proteins c-abl / metabolism
  • Pyrimidines / pharmacology
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • RNA, Small Interfering / pharmacology
  • Reverse Transcriptase Polymerase Chain Reaction
  • Thiazoles / pharmacology
  • Transfection

Substances

  • Benzamides
  • Chromones
  • DNA Primers
  • Homeobox A10 Proteins
  • Homeodomain Proteins
  • Morpholines
  • Phosphoinositide-3 Kinase Inhibitors
  • Piperazines
  • Protein Kinase Inhibitors
  • Pyrimidines
  • RNA, Messenger
  • RNA, Small Interfering
  • Thiazoles
  • HOXA10 protein, human
  • 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one
  • Imatinib Mesylate
  • Proto-Oncogene Proteins c-abl
  • Dasatinib