LABORATORY RESEARCH Downregulated Expression of hsa–miR–181c in Fanconi Anemia Patients: Implications in TNFα Regulation and Proliferation of Hematopoietic Progenitor Cells In this study researchers aimed to elucidate the role of miRNAs in the hematopoietic defects observed in fanconi anemia patients. [Blood] Abstract HIF-1α Deletion Partially Rescues Defects of Hematopoietic Stem Cell Quiescence Caused by Cited2 Deficiency In this study, the function of Cited2 in adult hematopoiesis was investigated in conditional knockout mice. [Blood] Abstract Characterization of Thrombopoietin-Responsive Progenitor Cells in Adult Mouse Bone Marrow with In Vivo Megakaryocyte and Erythroid Potential Identification of cell-surface antigen expression associated with hematopoietic lineage restriction has allowed prospective isolation of progenitor cells with defined hematopoietic potential. To clarify further the cellular origins of megakaryocyte commitment, researchers assessed the in vitro and in vivo megakaryocyte and platelet potential of defined progenitor populations in the adult mouse bone marrow. [Proc Natl Acad Sci USA] Abstract | Press Release Novel Pathways to Erythropoiesis Induced by Dimerization of Intracellular cMpl in Human Hematopoietic Progenitors The goal of this study was to define the hematopoietic progenitor stages at which dimerization of intracellular Mpl induces erythropoiesis, and the downstream molecular events that mediate this unanticipated effect. [Stem Cells] Abstract Non-Canonical NF-κB Signaling Regulates Hematopoietic Stem Cell Self-Renewal and Microenvironment Interactions Researchers generated RelB/NF-κB2 double-knockout (dKO) mice and found that dKO hematopoietic stem/progenitor cells have profoundly impaired engraftment and self-renewal activity after transplantation into wild-type recipients. [Stem Cells] Abstract Nonmyeloablative Conditioning Regimen to Increase Engraftment of Gene-Modified Hematopoietic Stem Cells in Young Rhesus Monkeys These studies establish a clinically relevant pediatric primate model to assess the effects of conditioning regimens on the engraftment of transduced hematopoietic stem cells and the immune responses to cells expressing a foreign gene product. [Mol Ther] Abstract ERK1 Regulates the Hematopoietic Stem Cell Niches This study reinforces the hypothesis of an active cross-talk between hematopoietic stem cells, their progeny and bone cells in the maintenance of the homeostasis of these compartments. [PLoS One] Abstract Zebrafish Models for Dyskeratosis Congenita Reveal Critical Roles of p53 Activation Contributing to Hematopoietic Defects through RNA Processing Through comparative analysis of morpholino oligonucleotide induced knockdown of dkc1 and a retrovirus insertion induced mutation of GAR1/nola1 in zebrafish, researchers demonstrate that hematopoietic defects are specifically recapitulated in these models and that these defects are significantly reduced in a p53 null mutant background. [PLoS One] Abstract CLINICAL RESEARCH A Phase I/II Study of Chemosensitization with the CXCR4 Antagonist Plerixafor in Relapsed or Refractory Acute Myeloid Leukemia In this phase I/II study, fifty-two patients with relapsed or refractory acute myeloid leukemia were treated with plerixafor in combination with mitoxantrone, etoposide and cytarabine. [Blood] Abstract Growth Factor-Associated Graft-versus-Host Disease and Mortality 10 years after Allogeneic Bone Marrow Transplantation This study analyzed the effects of growth factor on outcome after hematopoietic stem-cell transplantation with >9 years follow-up. [Br J Haematol] Abstract Aberrant Methylation and Decreased Expression of the RIZ1 Gene Are Frequent in Adult Acute Lymphoblastic Leukemia of T Cell Phenotype Scientists analyzed expression and promoter methylation status of the RIZ1 gene in newly diagnosed acute lymphoblastic leukemia patients by quantitative real-time reverse transcription polymerase chain reaction (PCR) and methylation-specific PCR respectively. [Leuk Lymphoma] Abstract |