title: Cotargeting signaling pathways driving survival and cell cycle circumvents resistance to Kit inhibitors in leukemia.
abstract: Oncogenic mutations leading to persistent kinase activities are associated with malignancies. Therefore, deciphering the signaling networks downstream of these oncogenic stimuli remains a challenge to gather insights into targeted therapy. To elucidate the biochemical networks connecting the Kit mutant to leukemogenesis, in the present study, we performed a global profiling of tyrosine-phosphorylated proteins from mutant Kit-driven murine leukemia proerythroblasts and identified Shp2 and Stat5 as proximal effectors of Kit. Shp2 or Stat5 gene depletion by sh-RNA, combined with pharmacologic inhibition of PI3kinase or Mek/Erk activities, revealed 2 distinct and independent signaling pathways contributing to malignancy. We demonstrate that cell survival is driven by the Kit/Shp2/Ras/Mek/Erk1/2 pathway, whereas the G(1)/S transition during the cell cycle is accelerated by both the Kit/Stat5 and Kit/PI3K/Akt pathways. The combined use of the clinically relevant drugs NVP-BEZ235, which targets the cell cycle, and Obatoclax, which targets survival, demonstrated synergistic effects to inhibit leukemia cell growth. This synergy was confirmed with a human mast leukemia cell line (HMC-1.2) that expresses mutant Kit. The results of the present study using liquid chromatography/tandem mass spectrometry analysis have elucidated signaling networks downstream of an oncogenic kinase, providing a molecular rationale for pathway-targeted therapy to treat cancer cells refractory to tyrosine kinase inhibitors.
authors.affiliation: INSERM U830, Institut Curie, 26 rue d'Ulm, Paris, France.
authors.forename: Dorothée
authors.initials: D
authors.lastname: Buet
authors.forename: Isabelle
authors.initials: I
authors.lastname: Gallais
authors.forename: Evelyne
authors.initials: E
authors.lastname: Lauret
authors.forename: Nicole
authors.initials: N
authors.lastname: Denis
authors.forename: Bérangère
authors.initials: B
authors.lastname: Lombard
authors.forename: François
authors.initials: F
authors.lastname: Guillonneau
authors.forename: Olivier
authors.initials: O
authors.lastname: Kosmider
authors.forename: Damarys
authors.initials: D
authors.lastname: Loew
authors.forename: Isabelle
authors.initials: I
authors.lastname: Dusanter-Fourt
authors.forename: Christel
authors.initials: C
authors.lastname: Guillouf
authors.forename: Patrick
authors.initials: P
authors.lastname: Mayeux
authors.forename: Françoise
authors.initials: F
authors.lastname: Moreau-Gachelin
mesh_terms: D000263:Adenylate Kinase / Q000037:antagonists & inhibitors / Q000502:physiology; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D019008:Drug Resistance, Neoplasm / Q000187:drug effects*; D005260:Female; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D007211:Indoles; D007946:Leukemia, Mast-Cell / Q000473:pathology; D051379:Mice; D008819:Mice, Nude; D008822:Mice, Transgenic; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors*; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010766:Phosphorylation / Q000187:drug effects; D019000:Phosphotyrosine / Q000032:analysis; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D011499:Protein Processing, Post-Translational / Q000187:drug effects; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology; D019009:Proto-Oncogene Proteins c-kit / Q000037:antagonists & inhibitors*; D011758:Pyrroles / Q000494:pharmacology; D011804:Quinolines / Q000494:pharmacology; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000494:pharmacology; D050799:STAT5 Transcription Factor / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects*; D014410:Tumor Stem Cell Assay
chemical_list: D000263:Adenylate Kinase; D000970:Antineoplastic Agents; D007093:Imidazoles; D007211:Indoles; D009363:Neoplasm Proteins; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D019000:Phosphotyrosine; D047428:Protein Kinase Inhibitors; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D019009:Proto-Oncogene Proteins c-kit; D011758:Pyrroles; D011804:Quinolines; D034741:RNA, Small Interfering; D050799:STAT5 Transcription Factor; C110939:adenylate kinase 1; C516725:Ptpn11 protein, mouse; C520962:obatoclax; C531198:dactolisib