Modulation of caspase-independent cell death leads to resensitization of imatinib mesylate-resistant cells

Cancer Res. 2009 Apr 1;69(7):3013-20. doi: 10.1158/0008-5472.CAN-08-2731. Epub 2009 Mar 24.

Abstract

Imatinib mesylate is widely used for the treatment of patients with chronic myelogenous leukemia (CML). This compound is very efficient in killing Bcr-Abl-positive cells in a caspase-dependent manner. Nevertheless, several lines of evidence indicated that caspase-mediated cell death (i.e., apoptosis) is not the only type of death induced by imatinib. The goal of our study was to evaluate the importance of the newly described caspase-independent cell death (CID) in Bcr-Abl-positive cells. We established in several CML cell lines that imatinib, in conjunction with apoptosis, also induced CID. CID was shown to be as efficient as apoptosis in preventing CML cell proliferation and survival. We next investigated the potential implication of a recently identified mechanism used by cancer cells to escape CID through overexpression of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH). We showed here, in several CML cell lines, that GAPDH overexpression was sufficient to induce protection from CID. Furthermore, imatinib-resistant Bcr-Abl-positive cell lines were found to spontaneously overexpress GAPDH. Finally, we showed that a GAPDH partial knockdown, using specific short hairpin RNAs, was sufficient to resensitize those resistant cells to imatinib-induced cell death. Taken together, our results indicate that CID is an important effector of imatinib-mediated cell death. We also established that GAPDH overexpression can be found in imatinib-resistant Bcr-Abl-positive cells and that its down-regulation can resensitize those resistant cells to imatinib-induced death. Therefore, drugs able to modulate GAPDH administered together with imatinib could find some therapeutic benefits in CML patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Chloromethyl Ketones / pharmacology
  • Antineoplastic Agents / pharmacology*
  • Apoptosis / drug effects
  • Apoptosis / physiology
  • Benzamides
  • Caspase Inhibitors
  • Caspases / metabolism*
  • Cell Death / drug effects*
  • Cell Death / physiology
  • Cell Line, Tumor
  • Down-Regulation
  • Fusion Proteins, bcr-abl / biosynthesis
  • Glyceraldehyde-3-Phosphate Dehydrogenases / biosynthesis
  • Glyceraldehyde-3-Phosphate Dehydrogenases / genetics
  • Glyceraldehyde-3-Phosphate Dehydrogenases / metabolism
  • Humans
  • Imatinib Mesylate
  • K562 Cells
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / drug therapy*
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / enzymology
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / pathology
  • Piperazines / pharmacology*
  • Pyrimidines / pharmacology*
  • Quinolines / pharmacology
  • RNA, Small Interfering / genetics

Substances

  • Amino Acid Chloromethyl Ketones
  • Antineoplastic Agents
  • Benzamides
  • Caspase Inhibitors
  • Piperazines
  • Pyrimidines
  • Quinolines
  • RNA, Small Interfering
  • abl-bcr fusion protein, human
  • quinoline-val-asp(OMe)-CH2-OPH
  • Imatinib Mesylate
  • Glyceraldehyde-3-Phosphate Dehydrogenases
  • Fusion Proteins, bcr-abl
  • Caspases