title: Regulated expression of microRNAs in normal and polycythemia vera erythropoiesis.
abstract: OBJECTIVE
  Polycythemia vera (PV) is a myeloproliferative disorder, arising from the acquired mutation(s) of a hematopoietic stem cell. The JAK2 V617F somatic mutation is found in most PV patients; however, it is not the disease-initiating mutation. Because microRNAs (miRNAs) play a regulatory role in hematopoiesis, we studied miRNA expressions in PV and normal erythropoiesis.
  
  
  METHODS
  Peripheral blood mononuclear cells were cultured in a three-phase liquid system resulting in synchronized expansion of erythroid progenitors. Using gene-expression profiling by CombiMatrix MicroRNArray, we searched for PV-specific changes at days 1, 14, and 21. Twelve miRNA candidates were then reevaluated by quantitative real-time polymerase chain reaction in a larger number of samples obtained from progenitors at the same stage of differentiation.
  
  
  RESULTS
  A significant difference in miR-150 expression was found in PV. In normal erythropoiesis, three expression patterns of miRNAs were observed: progressive downregulation of miR-150, miR-155, miR-221, miR-222; upregulation of miR-451, miR-16 at late stages of erythropoiesis; and biphasic regulation of miR-339, miR-378. The miR-451 appears to be erythroid-specific.
  
  
  CONCLUSIONS
  We identified the miRNAs with regulated expression in erythropoiesis; one appeared to be PV-specific. Their miRNA expression levels define early, intermediate, and late stages of erythroid differentiation. The validity of our findings was confirmed in nonexpanded peripheral blood cells.
authors.affiliation: Hematology Division, Department of Pathology, University of Utah, School of Medicine, Salt Lake City, UT 84132, USA.
authors.forename: Hana
authors.initials: H
authors.lastname: Bruchova
authors.forename: Donghoon
authors.initials: D
authors.lastname: Yoon
authors.forename: Archana M
authors.initials: AM
authors.lastname: Agarwal
authors.forename: Joshua
authors.initials: J
authors.lastname: Mendell
authors.forename: Josef T
authors.initials: JT
authors.lastname: Prchal
mesh_terms: D016022:Case-Control Studies; D002454:Cell Differentiation / Q000235:genetics; D002478:Cells, Cultured; D015672:Erythroid Precursor Cells; D004920:Erythropoiesis / Q000235:genetics*; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007963:Leukocytes, Mononuclear; D035683:MicroRNAs / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis; D011087:Polycythemia Vera / Q000235:genetics*; D013997:Time Factors
chemical_list: D035683:MicroRNAs