Engraftment and differentiation of donor hematopoietic stem cells is decisive for the clinical success of allogeneic stem cell transplantation (alloSCT) and depends on the recipient's bone marrow (BM) niche. A damaged niche contributes to poor graft function after alloSCT; however, the underlying mechanisms and the role of BM multipotent mesenchymal stromal cells (MSC) are ill-defined. Upon multivariate analysis in 732 individuals, we observed a reduced presence of proliferation-capable MSC in BM aspirates from patients (N = 196) who had undergone alloSCT.
View Article and Find Full Text PDFHematopoiesis, the formation of blood cells from hematopoietic stem cells (HSC), is a highly regulated process. Since the discovery of microRNAs (miRNAs), several studies have shown their significant role in the regulation of the hematopoietic system. Impaired expression of miRNAs leads to disrupted cellular pathways and in particular causes loss of hematopoietic ability.
View Article and Find Full Text PDFActive related () gene deactivates ras-related C3 botulinum toxin substrate 1 (RAC1), which plays an essential role in regulating normal hematopoiesis and in leukemia. gene, closely related to ABR, acts as a tumor suppressor in chronic myeloid leukemia and has overlapping functions with . Evidence for a putative tumor suppressor role of has been shown in several solid tumors, in which deletion of ABR is present.
View Article and Find Full Text PDFTranscription factor C/EBPα is a master regulator of myelopoiesis and its inactivation is associated with acute myeloid leukemia. Deregulation of C/EBPα by microRNAs during granulopoiesis or acute myeloid leukemia development has not been studied. Here we show that oncogenic miR-182 is a strong regulator of C/EBPα.
View Article and Find Full Text PDFIn acute promyelocytic leukemia (APL), all-trans retinoic acid (ATRA) treatment induces granulocytic maturation and complete remission of leukemia. microRNAs are known to be critical players in the formation of the leukemic phenotype. In this study, we report downregulation of the miR-181a/b gene cluster in APL blasts and NB4 leukemia cells upon ATRA treatment as a key event in the drug response.
View Article and Find Full Text PDFThe transcription factor CCAAT enhancer binding protein α (C/EBPα) is a master regulator in granulopoiesis and is frequently disrupted in acute myeloid leukemia (AML). We have previously shown that C/EBPα exerts its effects by regulating microRNAs (miRs) such as miR-223 and miR-34a. Here, we confirm miR-30c as a novel important target of C/EBPα during granulopoiesis.
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