title: Molecular characterization and sensitivity of STI-571 (imatinib mesylate, Gleevec)-resistant, Bcr-Abl-positive, human acute leukemia cells to SRC kinase inhibitor PD180970 and 17-allylamino-17-demethoxygeldanamycin.
abstract: Using human acute leukemia HL-60/Bcr-Abl (with ectopic expression of p185 Bcr-Abl) and K562 cells (with endogenous expression of p210 Bcr-Abl) subjected to a continuous selection pressure of up to 1.0 micro M Gleevec (imatinib mesylate, STI-571), we have isolated Gleevec-resistant K562 R (+Bcr-Abl), K562 R (-Bcr-Abl), and HL-60/Bcr-Abl R cells, which display disparate level and activity of Bcr-Abl tyrosine kinase (TK). As compared with their sensitive counterparts, Gleevec-resistant cell types were >/=5-fold resistant to Gleevec-induced apoptosis. Bcr-Abl protein levels were significantly increased in HL-60/Bcr-Abl R and K562 R (+Bcr-Abl) cells, but K562 R (-Bcr-Abl) cells showed a marked decline in the mRNA and protein levels and activity of Bcr-Abl. Bcr-Abl TK level and activity corresponded to the signal transducers and activators of transcription-5 DNA binding activity and up-regulation of heat shock protein 70 levels. The decline in Bcr-Abl expression and TK activity in K562 R (-Bcr-Abl) cells was associated with reduced AKT kinase and signal transducers and activators of transcription-5 DNA binding activities and increased sensitivity to the death ligand Apo-2 ligand/tumor necrosis factor-related apoptosis-inducing ligand and 1-beta-D-arabinofuranosylcytosine-induced apoptosis. All Gleevec-resistant cell types were sensitive to 17-allylamino-17-demethoxygeldanamycin (17-AAG)- and PD180970 (a SRC and Bcr-Abl TK inhibitor)-induced apoptosis. Treatment with 17-AAG or PD180970 also induced apoptosis of CD34+ leukemic cells from three patients with chronic myeloid leukemia in blast crisis who had progressive leukemia while receiving Gleevec therapy. Taken together, these findings indicate that in addition to overexpression or mutations in Bcr-Abl, resistance to Gleevec may also develop due to a loss of Bcr-Abl expression. These findings also support the rationale to test the in vivo efficacy of 17-AAG and PD180970 against STI-571-resistant Bcr-Abl-positive acute leukemias.
authors.affiliation: Interdisciplinary Oncology Program, Moffitt Cancer Center, University of South Florida, Tampa 33612, USA.
authors.forename: Ramadevi
authors.initials: R
authors.lastname: Nimmanapalli
authors.forename: Erica
authors.initials: E
authors.lastname: O'Bryan
authors.forename: Mei
authors.initials: M
authors.lastname: Huang
authors.forename: Purva
authors.initials: P
authors.lastname: Bali
authors.forename: Pearlie Kay
authors.initials: PK
authors.lastname: Burnette
authors.forename: Thomas
authors.initials: T
authors.lastname: Loughran
authors.forename: James
authors.initials: J
authors.lastname: Tepperberg
authors.forename: Richard
authors.initials: R
authors.lastname: Jove
authors.forename: Kapil
authors.initials: K
authors.lastname: Bhalla
mesh_terms: D001549:Benzamides; D016227:Benzoquinones; D001752:Blast Crisis; D003561:Cytarabine / Q000494:pharmacology; D004268:DNA-Binding Proteins / Q000378:metabolism; D019008:Drug Resistance, Neoplasm; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D016044:Fusion Proteins, bcr-abl / Q000096:biosynthesis* / Q000378:metabolism; D018922:HL-60 Cells / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D000068877:Imatinib Mesylate; D020014:K562 Cells / Q000187:drug effects* / Q000378:metabolism; D047029:Lactams, Macrocyclic; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000188:drug therapy / Q000473:pathology; D008894:Milk Proteins; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010879:Piperazines / Q000494:pharmacology*; D017346:Protein Serine-Threonine Kinases; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt; D011728:Pyridones / Q000494:pharmacology*; D011743:Pyrimidines / Q000494:pharmacology*; D017828:Rifabutin / Q000031:analogs & derivatives* / Q000494:pharmacology*; D050799:STAT5 Transcription Factor; D015534:Trans-Activators / Q000378:metabolism; D019061:src-Family Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D001549:Benzamides; D016227:Benzoquinones; D004268:DNA-Binding Proteins; D004791:Enzyme Inhibitors; D047029:Lactams, Macrocyclic; D008894:Milk Proteins; D010879:Piperazines; D011518:Proto-Oncogene Proteins; D011728:Pyridones; D011743:Pyrimidines; D050799:STAT5 Transcription Factor; D015534:Trans-Activators; D003561:Cytarabine; D017828:Rifabutin; C112765:tanespimycin; D000068877:Imatinib Mesylate; D011505:Protein-Tyrosine Kinases; D016044:Fusion Proteins, bcr-abl; D019061:src-Family Kinases; C494918:AKT1 protein, human; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; C410732:PD 180970