title: Ph(-) myeloproliferative neoplasm red blood cells display deregulation of IQGAP1-Rho GTPase signaling depending on CALR/JAK2 status.
abstract: Besides genetic abnormalities in MPN patients, several studies have reported alterations in protein expression that could contribute towards the clinical phenotype. However, little is known about protein modifications in Ph-MPN erythrocytes. In this context, we used a quantitative mass spectrometry proteomics approach to study the MPN erythrocyte proteome. LC-MS/MS (LTQ Orbitrap) analysis led to the identification of 51 and 86 overexpressed proteins in Polycythemia Vera and Essential Thrombocythemia respectively, compared with controls. Functional comparison using pathway analysis software showed that the Rho GTPase family signaling pathways were deregulated in MPN patients. In particular, IQGAP1 was significantly overexpressed in MPNs compared with controls. Additionally, Western-blot analysis not only confirmed IQGAP1 overexpression, but also showed that IQGAP1 levels depended on the patient's genotype. Moreover, we found that in JAK2V617F patients IQGAP1 could bind RhoA, Rac1 and Cdc42 and consequently recruit activated GTP-Rac1 and the cytoskeleton motility protein PAK1. In CALR(+) patients, IQGAP1 was not overexpressed but immunoprecipitated with RhoGDI. In JAK2V617F transduced Ba/F3 cells we confirmed JAK2 inhibitor-sensitive overexpression of IQGAP1/PAK1. Altogether, our data demonstrated alterations of IQGAP1/Rho GTPase signaling in MPN erythrocytes dependent on JAK2/CALR status, reinforcing the hypothesis that modifications in erythrocyte signaling pathways participate in Ph-MPN pathogenesis.
authors: TheREx Team "Thérapeutique recombinante expérimentale", TIMC-IMAG Laboratory, "Techniques de l'Ingénierie Médicale et de la Complexité - Informatique, Mathématiques et Applications de Grenoble", UMR, UJF, CNRS 5525, University of Grenoble Alpes, France. Electronic address: nuriasocoro@gmail.com.
authors: Nuria
authors: N
authors: Socoro-Yuste
authors: TheREx Team "Thérapeutique recombinante expérimentale", TIMC-IMAG Laboratory, "Techniques de l'Ingénierie Médicale et de la Complexité - Informatique, Mathématiques et Applications de Grenoble", UMR, UJF, CNRS 5525, University of Grenoble Alpes, France.
authors: Marie-Claire
authors: MC
authors: Dagher
authors: Plateforme Protéomique de la Génopole Toulouse Midi-Pyrénées, Institut de Pharmacologie et de Biologie Structurale, CNRS, UMR, 5089 Toulouse, France.
authors: Anne
authors: A
authors: Gonzalez De Peredo
authors: TheREx Team "Thérapeutique recombinante expérimentale", TIMC-IMAG Laboratory, "Techniques de l'Ingénierie Médicale et de la Complexité - Informatique, Mathématiques et Applications de Grenoble", UMR, UJF, CNRS 5525, University of Grenoble Alpes, France.
authors: Julie
authors: J
authors: Mondet
authors: Department of clinical proteomics, University of Geneva, Switzerland.
authors: Affif
authors: A
authors: Zaccaria
authors: Plateforme Protéomique de la Génopole Toulouse Midi-Pyrénées, Institut de Pharmacologie et de Biologie Structurale, CNRS, UMR, 5089 Toulouse, France.
authors: Florence
authors: F
authors: Roux Dalvai
authors: INSERM, UMR1170, Gustave Roussy, Université Paris-Sud, Villejuif, France.
authors: Isabelle
authors: I
authors: Plo
authors: TheREx Team "Thérapeutique recombinante expérimentale", TIMC-IMAG Laboratory, "Techniques de l'Ingénierie Médicale et de la Complexité - Informatique, Mathématiques et Applications de Grenoble", UMR, UJF, CNRS 5525, University of Grenoble Alpes, France; Clinique Universitaire d'Hématologie, Grenoble Alpes University Hospital, France.
authors: Jean Yves
authors: JY
authors: Cahn
authors: TheREx Team "Thérapeutique recombinante expérimentale", TIMC-IMAG Laboratory, "Techniques de l'Ingénierie Médicale et de la Complexité - Informatique, Mathématiques et Applications de Grenoble", UMR, UJF, CNRS 5525, University of Grenoble Alpes, France; Laboratoire d'Hématologie cellulaire, Institut de Biologie et Pathologie, Grenoble Alpes University Hospital, France.
authors: Pascal
authors: P
authors: Mossuz
mesh_terms: D014408:Biomarkers, Tumor / Q000097:blood / Q000235:genetics*; D037282:Calreticulin / Q000097:blood / Q000235:genetics*; D016022:Case-Control Studies; D002460:Cell Line; D002853:Chromatography, Liquid; D004912:Erythrocytes / Q000201:enzymology*; D020022:Genetic Predisposition to Disease; D006801:Humans; D053614:Janus Kinase 2 / Q000097:blood / Q000235:genetics*; D009154:Mutation; D009196:Myeloproliferative Disorders / Q000097:blood / Q000175:diagnosis / Q000201:enzymology* / Q000235:genetics; D010641:Phenotype; D011485:Protein Binding; D040901:Proteomics / Q000379:methods; D015398:Signal Transduction; D053719:Tandem Mass Spectrometry; D014162:Transfection; D020764:cdc42 GTP-Binding Protein / Q000378:metabolism; D054462:p21-Activated Kinases / Q000378:metabolism; D020830:rac1 GTP-Binding Protein / Q000378:metabolism; D020703:ras GTPase-Activating Proteins / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D020742:rhoA GTP-Binding Protein / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; C576483:CALR protein, human; D037282:Calreticulin; C101203:IQ motif containing GTPase activating protein 1; C107953:RAC1 protein, human; D020703:ras GTPase-Activating Proteins; C066737:RHOA protein, human; C507924:JAK2 protein, human; D053614:Janus Kinase 2; C515903:PAK1 protein, human; D054462:p21-Activated Kinases; D020764:cdc42 GTP-Binding Protein; D020830:rac1 GTP-Binding Protein; D020742:rhoA GTP-Binding Protein
keywords: Erythrocyte proteome; IQGAP1; Myeloproliferative neoplasms; Rho GTPases