title: Gaining insights into the Bcr-Abl activity-independent mechanisms of resistance to imatinib mesylate in KCL22 cells: a comparative proteomic approach.
abstract: Imatinib mesylate is a potent inhibitor of Bcr-Abl tyrosine kinase, an oncoprotein that plays a key role in the development of chronic myeloid leukemia. Consequently, imatinib is used as front-line therapy for this disease. A major concern in imatinib treatment is the emergence of resistance to the drug. Here we used the imatinib-resistant KCL22R and imatinib-sensitive KCL22S cells in which none of the known resistance mechanisms has been detected and hence novel Bcr-Abl activity-independent mechanisms could be envisaged. We characterized proteins that were differentially expressed between the KCL22R and KCL22S cells. Using two-dimensional differential gel electrophoresis coupled with mass spectrometry and Western blot analysis we identified 51 differentially expressed proteins: 27 were over-expressed and 24 were under-expressed in KCL22R versus KCL22S cells. Several of these proteins are likely to be involved in such survival mechanisms as modulation of redox balance and activation of anti-apoptotic pathways mediated by NF-kappaB and Ras-MAPK signaling. The data reported may be useful for further studies on mechanisms of imatinib resistance and for the screening of biomarkers to develop new combinatorial therapeutic approaches.
authors.affiliation: CEINGE Biotecnologie Avanzate Scarl, Napoli, Italy.
authors.forename: Irene
authors.initials: I
authors.lastname: Colavita
authors.forename: Nicola
authors.initials: N
authors.lastname: Esposito
authors.forename: Rosanna
authors.initials: R
authors.lastname: Martinelli
authors.forename: Francesca
authors.initials: F
authors.lastname: Catanzano
authors.forename: Junia V
authors.initials: JV
authors.lastname: Melo
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Pane
authors.forename: Margherita
authors.initials: M
authors.lastname: Ruoppolo
authors.forename: Francesco
authors.initials: F
authors.lastname: Salvatore
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001549:Benzamides; D014408:Biomarkers, Tumor / Q000378:metabolism*; D015153:Blotting, Western; D019008:Drug Resistance, Neoplasm; D015180:Electrophoresis, Gel, Two-Dimensional; D016044:Fusion Proteins, bcr-abl / Q000235:genetics / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D000068877:Imatinib Mesylate; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000188:drug therapy* / Q000473:pathology; D009249:NADP / Q000378:metabolism; D010879:Piperazines / Q000627:therapeutic use*; D020543:Proteome / Q000032:analysis*; D011743:Pyrimidines / Q000627:therapeutic use*; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D001549:Benzamides; D014408:Biomarkers, Tumor; D010879:Piperazines; D020543:Proteome; D011743:Pyrimidines; D012333:RNA, Messenger; D009249:NADP; D000068877:Imatinib Mesylate; D016044:Fusion Proteins, bcr-abl; D005978:Glutathione