title: Targeting PYK2 mediates microenvironment-specific cell death in multiple myeloma.
abstract: Multiple myeloma (MM) remains an incurable malignancy due, in part, to the influence of the bone marrow microenvironment on survival and drug response. Identification of microenvironment-specific survival signaling determinants is critical for the rational design of therapy and elimination of MM. Previously, we have shown that collaborative signaling between β1 integrin-mediated adhesion to fibronectin and interleukin-6 confers a more malignant phenotype via amplification of signal transducer and activator of transcription 3 (STAT3) activation. Further characterization of the events modulated under these conditions with quantitative phosphotyrosine profiling identified 193 differentially phosphorylated peptides. Seventy-seven phosphorylations were upregulated upon adhesion, including PYK2/FAK2, Paxillin, CASL and p130CAS consistent with focal adhesion (FA) formation. We hypothesized that the collaborative signaling between β1 integrin and gp130 (IL-6 beta receptor, IL-6 signal transducer) was mediated by FA formation and proline-rich tyrosine kinase 2 (PYK2) activity. Both pharmacological and molecular targeting of PYK2 attenuated the amplification of STAT3 phosphorylation under co-stimulatory conditions. Co-culture of MM cells with patient bone marrow stromal cells (BMSC) showed similar β1 integrin-specific enhancement of PYK2 and STAT3 signaling. Molecular and pharmacological targeting of PYK2 specifically induced cell death and reduced clonogenic growth in BMSC-adherent myeloma cell lines, aldehyde dehydrogenase-positive MM cancer stem cells and patient specimens. Finally, PYK2 inhibition similarly attenuated MM progression in vivo. These data identify a novel PYK2-mediated survival pathway in MM cells and MM cancer stem cells within the context of microenvironmental cues, providing preclinical support for the use of the clinical stage FAK/PYK2 inhibitors for treatment of MM, especially in a minimal residual disease setting.
authors.affiliation: Chemical Biology and Molecular Medicine Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.|Department of Malignant Hematology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
authors.forename: M B
authors.initials: MB
authors.lastname: Meads
authors.affiliation: Proteomics Core Facility, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
authors.forename: B
authors.initials: B
authors.lastname: Fang
authors.affiliation: Chemical Biology and Molecular Medicine Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.|Department of Malignant Hematology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
authors.forename: L
authors.initials: L
authors.lastname: Mathews
authors.affiliation: Chemical Biology and Molecular Medicine Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.|Department of Malignant Hematology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
authors.forename: J
authors.initials: J
authors.lastname: Gemmer
authors.affiliation: Chemical Biology and Molecular Medicine Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.|Department of Malignant Hematology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
authors.forename: L
authors.initials: L
authors.lastname: Nong
authors.affiliation: Chemical Biology and Molecular Medicine Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.|Department of Malignant Hematology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
authors.forename: I
authors.initials: I
authors.lastname: Rosado-Lopez
authors.affiliation: Chemical Biology and Molecular Medicine Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.|Department of Malignant Hematology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
authors.forename: T
authors.initials: T
authors.lastname: Nguyen
authors.affiliation: Verastem, Inc., Needham, Massachusetts, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Ring
authors.affiliation: Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: W
authors.initials: W
authors.lastname: Matsui
authors.affiliation: ISIS Pharmaceuticals, Carlsbad, CA, USA.
authors.forename: A R
authors.initials: AR
authors.lastname: MacLeod
authors.affiliation: Verastem, Inc., Needham, Massachusetts, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Pachter
authors.affiliation: Department of Molecular Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
authors.forename: L A
authors.initials: LA
authors.lastname: Hazlehurst
authors.affiliation: Proteomics Core Facility, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.|Department of Molecular Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
authors.forename: J M
authors.initials: JM
authors.lastname: Koomen
authors.affiliation: Chemical Biology and Molecular Medicine Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.|Department of Malignant Hematology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA.
authors.forename: K H
authors.initials: KH
authors.lastname: Shain
mesh_terms: D000818:Animals; D016923:Cell Death / Q000502:physiology; D045744:Cell Line, Tumor; D005260:Female; D051418:Focal Adhesion Kinase 2 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism; D053613:Janus Kinase 1 / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D058990:Molecular Targeted Therapy; D009101:Multiple Myeloma / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D050796:STAT3 Transcription Factor / Q000378:metabolism; D015398:Signal Transduction; D059016:Tumor Microenvironment
chemical_list: C508600:IL6 protein, human; D015850:Interleukin-6; D047428:Protein Kinase Inhibitors; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human; D051418:Focal Adhesion Kinase 2; C507904:JAK1 protein, human; D053613:Janus Kinase 1