Clin Chem Lab Med 2014; aop a Martina Montagnana and Elisa Danese contributed equally to this work. *Corresponding author: Marco Benati, Department of Life and Reproduction Sciences, Clinical Biochemistry Section, University of Verona, Hospital “Policlinico G.B. Rossi”, P.le LA Scuro 10, 37134 Verona, Italy, Phone: +39 45 8124418, Fax: +39 45 8027484, E-mail: marco.benati@univr.it Martina Montagnana, Elisa Danese, Giovanna De Matteis, Elisa Paviati and Gian Cesare Guidi: Department of Life and Reproduction Sciences, Clinical Biochemistry Section, University of Verona, Verona, Italy Dino Veneri: Department of Medicine, Haematology Section, University of Verona, Verona, Italy Marco Benati*, Martina Montagnana a , Elisa Danese a , Giovanna De Matteis, Dino Veneri, Elisa Paviati and Gian Cesare Guidi Role of JAK2 V617F mutation and aberrant expression of microRNA-143 in myeloproliferative neoplasms DOI 10.1515/cclm-2014-0858 Received August 26, 2014; accepted November 20, 2014 Abstract Background: Myeloproliferative neoplasms (MPNs) are clonal myeloid disorders characterized by the overproduc- tion of mature blood cells. The pathogenetic hallmark of MPNs is the dysregulation of JAK-STAT signaling, usually associated with the JAK2 V617F mutation. Multiple addi- tional genetic and epigenetic alterations that constitu- tively activate the JAK-STAT signaling pathway have been described, including the modulation of the microRNAs (miRs) expression levels. The aims of our study were to investigate JAK2 V617F mutation allele burden and miR-143 expression levels in MPNs patients and to investi- gate the correlation between these genetic signatures and hematological parameters. Methods: In total 78 patients with a clinical diagnosis of polycythemia vera (PV), essential thrombocythemia (ET) and idiopathic myelofibrosis (IM), made according to the WHO 2008 criteria, were included in the study. Twenty healthy subjects were checked as controls. Quantifica- tion of JAK2 V617F mutation and miR-143 expression levels were determined by real-time quantitative polymerase chain reaction. Results: The miR-143 expression in MPNs patients was 2.97- fold higher than in controls. JAK2 V617F mutation allele burden and miR-143 expression level resulted higher in PV and IM respect to ET patients. Patients who had V617F allele burden > 50% displayed a higher miRNA-143 expres- sion level than patients with allele burden < 50%. In MPNs patients, a statistically significant positive correlation was observed between JAK2 V617F mutation allele burden and hemoglobin and hematocrit values and between miR-143 expression levels and platelet count. Conclusions: Our findings of aberrant miR-143 expression support the concept that factors other than JAK2 V617F mutation may contribute to the pathogenesis and some clinical signs of MPNs. Keywords: JAK2 V617F; miR-143; myeloproliferative neoplasms. Introduction Myeloproliferative neoplasms (MPNs), also known as myeloproliferative disorders (MPDs), are chronic cancers characterized by abnormal clonal expansion of a myeloid hematopoietic stem/progenitor cell followed by overpro- duction of mature blood cells, like red cells, white cells and platelets, alone or in combination. These disorders may be complicated by thrombosis and/or hemorrhage and some- times may evolve into acute myeloid leukemia [1, 2]. Philadelphia-negative MPNs include polycythemia vera (PV), essential thrombocythemia (ET) and idiopathic myelofibrosis (IM) [3]. The molecular pathogenesis of MPNs is character- ized by a somatic mutation (V617F) in exon 14 of the JAK2, the gene encoding Janus kinase 2, with a substitution of a valine (V) with a phenylalanine (F) within the autoin- hibitory pseudokinase domain JH2 of the protein. JAK2 is a non-receptor tyrosine kinase involved in the JAK-STAT sign- aling pathway, which plays a key role in several cellular Brought to you by | University of California - San Francisco Authenticated Download Date | 2/18/15 3:45 PM