LABORATORY RESEARCH A Single Oncogenic Enhancer Rearrangement Causes Concomitant EVI1 and GATA2 Deregulation in Leukemia AML with inv(3)/t(3;3) is associated with aberrant expression of the stem-cell regulator EVI1. Applying functional genomics and genome-engineering, scientists demonstrated that both 3q rearrangements reposition a distal GATA2 enhancer to ectopically activate EVI1 and simultaneously confer GATA2 functional haploinsufficiency, previously identified as the cause of sporadic familial AML/MDS and MonoMac/Emberger syndromes. [Cell] Abstract | Graphical Abstract Analysis of the DNA Methylome and Transcriptome in Granulopoiesis Reveal Timed Changes and Dynamic Enhancer Methylation Scientists characterized changes in DNA methylation and gene expression during granulopoiesis using four distinct cell populations ranging from the oligopotent common myeloid progenitor stage to terminally differentiated neutrophils. [Blood] Abstract | Press Release JAK2V617F-Homozygosity Drives a Phenotypic Switch between Myeloproliferative Neoplasms in a Murine Model, but Is Insufficient to Sustain Clonal Expansion Researchers provided direct genetic evidence and demonstrated that homozygosity for human JAK2V617F in knock-in mice results in a striking phenotypic switch from an essential thrombocythemia-like to polycythemia vera-like phenotype. The resultant erythrocytosis is driven by increased numbers of early erythroid progenitors and enhanced erythroblast proliferation whereas reduced platelet numbers are associated with impaired platelet survival. [Blood] Abstract CD44 Standard and CD44v10 Isoform Expression on Leukemia Cells Distinctly Influences Niche Embedding of Hematopoietic Stem Cells A blockade of CD44 is considered a therapeutic option for the elimination of leukemia initiating cells. However, anti-panCD44 can interfere with hematopoiesis. Therefore, investigators explored whether a CD44 variant isoform (CD44v)-specific antibody can inhibit leukemia growth without attacking hematopoiesis. [J Hematol Oncol] Full Article Stem and Progenitor Cell Subsets Are Affected by JAK2 Signaling and Can Be Monitored by Flow Cytometry Investigators analyzed hematopoietic stem cell subsets with a series of stem cell markers in JAK2V617F transgenic mice, where the mutation is sufficient to cause myeloproliferative neoplasia with lymphocyte deficiency. [PLoS One] Full Article Overexpression of miR-125a in Myelodysplastic Syndrome CD34+ Cells Modulates NF-κB Activation and Enhances Erythroid Differentiation Arrest The authors studied the role of miR-125a/miR-125b in myelodysplastic syndromes (MDS) and their relationship with toll-like receptor (TLR) signaling and hematopoietic differentiation. Their results indicate that miR-125a is significantly overexpressed in MDS patients and correlates negatively with patient survival. [PLoS One] Full Article CLINICAL RESEARCH The Prognostic Impact of Minimal Residual Disease in Patients with Chronic Lymphocytic Leukemia Requiring First-Line Therapy Researchers retrospectively evaluated the impact of minimal residual disease on the outcome of 255 consecutive patients receiving any frontline therapy in the context of a detailed prognostic evaluation, including IGHV, TP53, NOTCH1 and SF3B1 mutations. [Haematologica] Abstract | Full Article Extramedullary Relapse of Acute Leukemia after Allogeneic Hematopoietic Stem Cell Transplantation: Different Characteristics between Acute Myeloid Leukemia and Acute Lymphoblastic Leukemia In order to investigate the incidence, risk factor and clinical outcome of extramedullary relapse for acute myeloid leukemia and acute lymphoblastic leukemia, scientists performed a retrospective analysis on 362 patients with acute leukemia who underwent allogeneic hematopoietic stem cell transplantation. [Biol Blood Marrow Transplant] Abstract |