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Sample records for hematopoietic myeloid precursors

  1. Tfe3 expression is closely associated to macrophage terminal differentiation of human hematopoietic myeloid precursors

    SciTech Connect

    Zanocco-Marani, Tommaso; Vignudelli, Tatiana; Gemelli, Claudia; Pirondi, Sara; Testa, Anna; Montanari, Monica; Parenti, Sandra; Tenedini, Elena; Grande, Alexis; Ferrari, Sergio . E-mail: sergio@unimo.it

    2006-12-10

    The MItf-Tfe family of basic helix-loop-helix leucine zipper (bHLH-Zip) transcription factors encodes four family members: MItf, Tfe3, TfeB and TfeC. In vitro, each protein of the family binds DNA in a homo- or heterodimeric form with other family members. Tfe3 is involved in chromosomal translocations recurrent in different tumors and it has been demonstrated, by in vivo studies, that it plays, redundantly with MItf, an important role in the process of osteoclast formation, in particular during the transition from mono-nucleated to multi-nucleated osteoclasts. Since mono-nucleated osteoclasts derive from macrophages we investigated whether Tfe3 might play a role upstream during hematopoietic differentiation. Here we show that Tfe3 is able to induce mono-macrophagic differentiation of U937 cells, in association with a decrease of cell proliferation and an increase of apoptosis. We also show that Tfe3 does not act physiologically during commitment of CD34+ hematopoietic stem cells (HSCs), since it is not able to direct HSCs toward a specific lineage as observed by clonogenic assay, but is a strong actor of terminal differentiation since it allows human primary myeloblasts' maturation toward the macrophage lineage.

  2. Involvement of primary mesenchymal precursors and hematopoietic bone marrow cells from chronic myeloid leukemia patients by BCR-ABL1 fusion gene.

    PubMed

    Chandia, Mauricio; Sayagués, José-María; Gutiérrez, María-Laura; Chillón, María-Laura; Aristizábal, José-Alejandro; Corrales, Alejandro; Castellanos, Marta; Melón, Alberto; Sánchez, María-Luz; Bárcena, Paloma; Matarraz, Sergio; González-González, María; Barrena, Susana; López, Antonio; Cañizo, María-Consuelo; Sánchez-Guijo, Fermín; Orfao, Alberto

    2014-03-01

    For decades now, it is well established that chronic myeloid leukemia (CML) is a hematopoietic stem cell(HPC) disorder. However, it remains to be determined whether BCR-ABL1 gene rearrangement occurs in a HPC or at an earlier stem cell and whether the degree of involvement of hematopoiesis by the BCR-ABL1 fusion gene relates to the response to therapy. Here, we have investigated by interphase fluorescence in situ hybridization (iFISH) the distribution of BCR-ABL1 fusion gene in FACS-sorted bone marrow (BM) populations of mesenchymal precursor cells (MPC) and other hematopoietic cell populations from 18 newly diagnosed CML patients. Overall, our results showed systematic involvement at relatively high percentages of BM maturing neutrophils (97%615%), basophils (95%612%), eosinophils (90%68%), CD341 precursors cells (90%67%),monocytes (84%630%), nucleated red blood cells (87%624%), and mast cells (77%633%). By contrast, MPC(30%634%), B-cells (15%627%), T-lymphocytes (50%626%), and NK-cells (35%634%) were involved at lower percentages. In 8/18 CML patients, 2 tumor BCR-ABL11 subclones were detected by iFISH. Of note, all tumor cell subclones were systematically detected in CD341 cells, whereas MPC were only involved by the ancestral tumor cell subclone. In summary, here we confirm the presence at diagnosis of the BCR-ABL1 fusion gene inMPC, CD341 precursors, and other different BM hematopoietic myeloid cell lineages from CML patients,including also in a significant fraction of cases, a smaller percentage of T, B, and NK lymphocytes.Interestingly, involvement of MPC was restricted to the ancestral BCR-ABL11 subclone. PMID:24779036

  3. Antibodies to myeloid precursor cells in autoimmune neutropenia.

    PubMed

    Hartman, K R; LaRussa, V F; Rothwell, S W; Atolagbe, T O; Ward, F T; Klipple, G

    1994-07-15

    Antibodies to mature blood neutrophils and to bone marrow myeloid cells have been described in the sera of some patients with apparent autoimmune neutropenia. To further explore the prevalence and specificities of antibodies to myeloid precursor cells, we evaluated sera from 148 patients with suspected autoimmune neutropenia for the presence of antibodies to neutrophils, to cultured myeloid cell lines, and to highly purified bone marrow myeloid progenitor cells. Using an immunofluorescence flow cytometric assay, we identified IgG antibodies in 42 (28%) of these sera that bound specifically to K562 cells, a multilineage cell line originally derived from a patient with chronic myelogenous leukemia. Twenty-two (15%) of the sera also contained IgG antibodies that bound specifically to the primitive myelomonocytic leukemia cell line KG1a. Twenty-five (17%) of the sera had IgG antibodies to myeloid cell lines in the absence of antibodies to mature neutrophils. There was a trend toward more severe neutropenia in patients with antibodies to K562 cells, without antineutrophil antibodies. In further studies, antibodies from 12 sera bound to mononuclear CD34+ cells that had been purified from normal human bone marrow by an immunomagnetic separation procedure. Moreover, two of these sera suppressed the growth of granulocyte-macrophage colony-forming units (CFU-GM) in methylcellulose cultures. The presence of antibodies to primitive hematopoietic cells in the sera of some patients with suspected immune neutropenia suggests that these antibodies may have a role in the pathogenesis of the neutropenia observed. PMID:7517722

  4. Proteomic Cornerstones of Hematopoietic Stem Cell Differentiation: Distinct Signatures of Multipotent Progenitors and Myeloid Committed Cells*

    PubMed Central

    Klimmeck, Daniel; Hansson, Jenny; Raffel, Simon; Vakhrushev, Sergey Y.; Trumpp, Andreas; Krijgsveld, Jeroen

    2012-01-01

    Regenerative tissues such as the skin epidermis, the intestinal mucosa or the hematopoietic system are organized in a hierarchical manner with stem cells building the top of this hierarchy. Somatic stem cells harbor the highest self-renewal activity and generate a series of multipotent progenitors which differentiate into lineage committed progenitors and subsequently mature cells. In this report, we applied an in-depth quantitative proteomic approach to analyze and compare the full proteomes of ex vivo isolated and FACS-sorted populations highly enriched for either multipotent hematopoietic stem/progenitor cells (HSPCs, LinnegSca-1+c-Kit+) or myeloid committed precursors (LinnegSca-1−c-Kit+). By employing stable isotope dimethyl labeling and high-resolution mass spectrometry, more than 5000 proteins were quantified. From biological triplicate experiments subjected to rigorous statistical evaluation, 893 proteins were found differentially expressed between multipotent and myeloid committed cells. The differential protein content in these cell populations points to a distinct structural organization of the cytoskeleton including remodeling activity. In addition, we found a marked difference in the expression of metabolic enzymes, including a clear shift of specific protein isoforms of the glycolytic pathway. Proteins involved in translation showed a collective higher expression in myeloid progenitors, indicating an increased translational activity. Strikingly, the data uncover a unique signature related to immune defense mechanisms, centering on the RIG-I and type-1 interferon response systems, which are installed in multipotent progenitors but not evident in myeloid committed cells. This suggests that specific, and so far unrecognized, mechanisms protect these immature cells before they mature. In conclusion, this study indicates that the transition of hematopoietic stem/progenitors toward myeloid commitment is accompanied by a profound change in processing of

  5. Hematopoietic Differentiation Is Required for Initiation of Acute Myeloid Leukemia.

    PubMed

    Ye, Min; Zhang, Hong; Yang, Henry; Koche, Richard; Staber, Philipp B; Cusan, Monica; Levantini, Elena; Welner, Robert S; Bach, Christian S; Zhang, Junyan; Krivtsov, Andrei V; Armstrong, Scott A; Tenen, Daniel G

    2015-11-01

    Mutations in acute myeloid leukemia (AML)-associated oncogenes often arise in hematopoietic stem cells (HSCs) and promote acquisition of leukemia stem cell (LSC) phenotypes. However, as LSCs often share features of lineage-restricted progenitors, the relative contribution of differentiation status to LSC transformation is unclear. Using murine MLL-AF9 and MOZ-TIF2 AML models, we show that myeloid differentiation to granulocyte macrophage progenitors (GMPs) is critical for LSC generation. Disrupting GMP formation by deleting the lineage-restricted transcription factor C/EBPa blocked normal granulocyte formation and prevented initiation of AML. However, restoring myeloid differentiation in C/EBPa mutants with inflammatory cytokines reestablished AML transformation capacity. Genomic analyses of GMPs, including gene expression and H3K79me2 profiling in conjunction with ATAC-seq, revealed a permissive genomic environment for activation of a minimal transcription program shared by GMPs and LSCs. Together, these findings show that myeloid differentiation is a prerequisite for LSC formation and AML development, providing insights for therapeutic development. PMID:26412561

  6. Hematopoietic Cell Transplantation Outcomes in Monosomal Karyotype Myeloid Malignancies.

    PubMed

    Pasquini, Marcelo C; Zhang, Mei-Jie; Medeiros, Bruno C; Armand, Philippe; Hu, Zhen-Huan; Nishihori, Taiga; Aljurf, Mahmoud D; Akpek, Görgün; Cahn, Jean-Yves; Cairo, Mitchell S; Cerny, Jan; Copelan, Edward A; Deol, Abhinav; Freytes, César O; Gale, Robert Peter; Ganguly, Siddhartha; George, Biju; Gupta, Vikas; Hale, Gregory A; Kamble, Rammurti T; Klumpp, Thomas R; Lazarus, Hillard M; Luger, Selina M; Liesveld, Jane L; Litzow, Mark R; Marks, David I; Martino, Rodrigo; Norkin, Maxim; Olsson, Richard F; Oran, Betul; Pawarode, Attaphol; Pulsipher, Michael A; Ramanathan, Muthalagu; Reshef, Ran; Saad, Ayman A; Saber, Wael; Savani, Bipin N; Schouten, Harry C; Ringdén, Olle; Tallman, Martin S; Uy, Geoffrey L; Wood, William A; Wirk, Baldeep; Pérez, Waleska S; Batiwalla, Minoo; Weisdorf, Daniel J

    2016-02-01

    The presence of monosomal karyotype (MK+) in acute myeloid leukemia (AML) is associated with dismal outcomes. We evaluated the impact of MK+ in AML (MK+AML, n = 240) and in myelodysplastic syndrome (MDS) (MK+MDS, n = 221) on hematopoietic cell transplantation outcomes compared with other cytogenetically defined groups (AML, n = 3360; MDS, n = 1373) as reported to the Center for International Blood and Marrow Transplant Research from 1998 to 2011. MK+ AML was associated with higher disease relapse (hazard ratio, 1.98; P < .01), similar transplantation-related mortality (TRM) (hazard ratio, 1.01; P = .90), and worse survival (hazard ratio, 1.67; P < .01) compared with those outcomes for other cytogenetically defined AML. Among patients with MDS, MK+ MDS was associated with higher disease relapse (hazard ratio, 2.39; P < .01), higher TRM (hazard ratio, 1.80; P < .01), and worse survival (HR, 2.02; P < .01). Subset analyses comparing chromosome 7 abnormalities (del7/7q) with or without MK+ demonstrated higher mortality for MK+ disease in for both AML (hazard ratio, 1.72; P < .01) and MDS (hazard ratio, 1.79; P < .01). The strong negative impact of MK+ in myeloid malignancies was observed in all age groups and using either myeloablative or reduced-intensity conditioning regimens. Alternative approaches to mitigate disease relapse in this population are needed. PMID:26327629

  7. HEBAlt enhances the T-cell potential of fetal myeloid-biased precursors.

    PubMed

    Braunstein, Marsela; Rajkumar, Paula; Claus, Carol L; Vaccarelli, Giovanna; Moore, Amanda J; Wang, Duncheng; Anderson, Michele K

    2010-12-01

    Hematopoiesis is controlled by the interplay between transcription factors and environmental signals. One of the primary determinants of the T-lineage choice is Delta-like (DL)-Notch signaling, which promotes T-cell development and inhibits B-cell development. We have found that the transcription factor HEBAlt is up-regulated in early hematopoietic precursors in response to DL-Notch signaling and that it can promote early T-cell development. Here, we identified a population of lineage-negative Sca-1⁻c-kit(+) (LK) cells in the mouse fetal liver that rapidly gave rise to myeloid cells and B cells but exhibited very little T-cell potential. However, forced expression of HEBAlt in these precursors restored their ability to develop into T cells. We also showed that Ikaros and Notch1 are up-regulated in response to HEBAlt over-expression and that activated Notch1 enhances the ability of LK cells to enter the T-cell lineage. Furthermore, the myeloid transcription factor C/EBPα is down-regulated in response to HEBAlt. We therefore propose that HEBAlt plays a role in the network that enforces the T-lineage fate and limits myeloid fate during hematopoiesis. PMID:21115673

  8. Transcriptome-wide profiling and posttranscriptional analysis of hematopoietic stem/progenitor cell differentiation toward myeloid commitment.

    PubMed

    Klimmeck, Daniel; Cabezas-Wallscheid, Nina; Reyes, Alejandro; von Paleske, Lisa; Renders, Simon; Hansson, Jenny; Krijgsveld, Jeroen; Huber, Wolfgang; Trumpp, Andreas

    2014-11-11

    Hematopoietic stem cells possess lifelong self-renewal activity and generate multipotent progenitors that differentiate into lineage-committed and subsequently mature cells. We present a comparative transcriptome analysis of ex vivo isolated mouse multipotent hematopoietic stem/progenitor cells (Lin(neg)SCA-1(+)c-KIT(+)) and myeloid committed precursors (Lin(neg)SCA-1(neg)c-KIT(+)). Our data display dynamic transcriptional networks and identify a stem/progenitor gene expression pattern that is characterized by cell adhesion and immune response components including kallikrein-related proteases. We identify 498 expressed lncRNAs, which are potential regulators of multipotency or lineage commitment. By integrating these transcriptome with our recently reported proteome data, we found evidence for posttranscriptional regulation of processes including metabolism and response to oxidative stress. Finally, our study identifies a high number of genes with transcript isoform regulation upon lineage commitment. This in-depth molecular analysis outlines the enormous complexity of expressed coding and noncoding RNAs and posttranscriptional regulation during the early differentiation steps of hematopoietic stem cells toward the myeloid lineage. PMID:25418729

  9. Vav promotes differentiation of human tumoral myeloid precursors

    SciTech Connect

    Bertagnolo, Valeria; Brugnoli, Federica; Mischiati, Carlo; Sereni, Alessia; Bavelloni, Alberto; Carini, Cinzia; Capitani, Silvano . E-mail: cps@unife.it

    2005-05-15

    Vav is one of the genetic markers that correlate with the differentiation of hematopoietic cells. In T and B cells, it appears crucial for both development and functions, while, in non-lymphoid hematopoietic cells, Vav seems not involved in cell maturation, but rather in the response of mature cells to agonist-dependent proliferation and phagocytosis. We have previously demonstrated that the amount and the tyrosine phosphorylation of Vav are up-regulated in both whole cells and nuclei of tumoral promyelocytes induced to granulocytic maturation by ATRA and that tyrosine-phosphorylated Vav does not display any ATRA-induced GEF activity but contributes to the regulation of PI 3-K activity. In this study, we report that Vav accumulates in nuclei of ATRA-treated APL-derived cells and that the down-modulation of Vav prevents differentiation of tumoral promyelocytes, indicating that it is a key molecule in ATRA-dependent myeloid maturation. On the other hand, the overexpression of Vav induces an increased expression of surface markers of granulocytic differentiation without affecting the maturation-related changes of the nuclear morphology. Consistent with an effect of Vav on the transcriptional machinery, array profiling shows that the inhibition of the Syk-dependent tyrosine phosphorylation of Vav reduces the number of ATRA-induced genes. Our data support the unprecedented notion that Vav plays crucial functions in the maturation process of myeloid cells, and suggest that Vav can be regarded as a potential target for the therapeutic treatment of myeloproliferative disorders.

  10. Characterization of the Murine Myeloid Precursor Cell Line MuMac-E8

    PubMed Central

    Fricke, Stephan; Riemschneider, Sina; Kohlschmidt, Janine; Hilger, Nadja; Fueldner, Christiane; Knauer, Jens; Sack, Ulrich; Emmrich, Frank; Lehmann, Jörg

    2014-01-01

    Starting point for the present work was the assumption that the cell line MuMac-E8 represents a murine cell population with stem cell properties. Preliminary studies already pointed to the expression of stem-cell associated markers and a self-regenerative potential of the cells. The cell line MuMac-E8 should be examined for their differential stage within stem cell hierarchy. MuMac-E8 cells were derived from a chimeric mouse model of arthritis. It could be shown that MuMac-E8 cells express mRNA of some genes associated with pluripotent stem cells (Nanog, Nucleostemin), of genes for hematopoietic markers (EPCR, Sca-1, CD11b, CD45), for the mesenchymal marker CD105 and of genes for the neural markers Pax-6 and Ezrin. In methylcellulose and May-Grünwald-Giemsa staining, hematopoietic colonies were obtained but the hematopoietic system of lethally irradiated mice could not be rescued. Osteogenic differentiation was not detectable. Thus, it became evident that MuMac-E8 represents not a stem cell line. However, MuMac-E8 cells expressed several myeloid surface markers (i.e. CD11b, F4/80, CD14, CD64), showed phagocytosis and is capable of producing nitric oxide. Thus, this cell line seems to be arrested an advanced stage of myeloid differentiation. Adherence data measured by impedance-based real-time cell analysis together with cell morphology data suggested that MuMac-E8 represents a new macrophage precursor cell line exhibiting weak adherence. This cell line is suitable as an in-vitro model for testing of macrophage functions. Moreover, it might be also useful for differentiation or reprogramming studies. PMID:25546418

  11. Successful hematopoietic cell transplantation in a patient with X-linked agammaglobulinemia and acute myeloid leukemia.

    PubMed

    Abu-Arja, Rolla F; Chernin, Leah R; Abusin, Ghada; Auletta, Jeffery; Cabral, Linda; Egler, Rachel; Ochs, Hans D; Torgerson, Troy R; Lopez-Guisa, Jesus; Hostoffer, Robert W; Tcheurekdjian, Haig; Cooke, Kenneth R

    2015-09-01

    X-linked agammaglobulinemia (XLA) is a primary immunodeficiency characterized by marked reduction in all classes of serum immunoglobulins and the near absence of mature CD19(+) B-cells. Although malignancy has been observed in patients with XLA, we present the first reported case of acute myeloid leukemia (AML) in a patient with XLA. We also demonstrate the complete correction of the XLA phenotype following allogeneic hematopoietic cell transplantation for treatment of the patient's leukemia. PMID:25900577

  12. Successful Hematopoietic Cell Transplantation in a Patient With X-linked Agammaglobulinemia and Acute Myeloid Leukemia

    PubMed Central

    Abu-Arja, Rolla F.; Chernin, Leah R.; Abusin, Ghada; Auletta, Jeffery; Cabral, Linda; Egler, Rachel; Ochs, Hans D.; Torgerson, Troy R.; Lopez-Guisa, Jesus; Hostoffer, Robert W.; Tcheurekdjian, Haig; Cooke, Kenneth R.

    2016-01-01

    X-linked agammaglobulinemia (XLA) is a primary immunodeficiency characterized by marked reduction in all classes of serum immunoglobulins and the near absence of mature CD19+ B-cells. Although malignancy has been observed in patients with XLA, we present the first reported case of acute myeloid leukemia (AML) in a patient with XLA. We also demonstrate the complete correction of the XLA phenotype following allogeneic hematopoietic cell transplantation for treatment of the patient’s leukemia. PMID:25900577

  13. BET Bromodomain Inhibition Suppresses the Function of Hematopoietic Transcription Factors in Acute Myeloid Leukemia.

    PubMed

    Roe, Jae-Seok; Mercan, Fatih; Rivera, Keith; Pappin, Darryl J; Vakoc, Christopher R

    2015-06-18

    The bromodomain and extraterminal (BET) protein BRD4 is a validated drug target in leukemia, yet its regulatory function in this disease is not well understood. Here, we show that BRD4 chromatin occupancy in acute myeloid leukemia closely correlates with the hematopoietic transcription factors (TFs) PU.1, FLI1, ERG, C/EBPα, C/EBPβ, and MYB at nucleosome-depleted enhancer and promoter regions. We provide evidence that these TFs, in conjunction with the lysine acetyltransferase activity of p300/CBP, facilitate BRD4 recruitment to their occupied sites to promote transcriptional activation. Chemical inhibition of BET bromodomains was found to suppress the functional output of each hematopoietic TF, thereby interfering with essential lineage-specific transcriptional circuits in this disease. These findings reveal a chromatin-based signaling cascade comprised of hematopoietic TFs, p300/CBP, and BRD4 that supports leukemia maintenance and is suppressed by BET bromodomain inhibition. PMID:25982114

  14. Regulation of cell surface receptors for different hematopoietic growth factors on myeloid leukemic cells.

    PubMed Central

    Lotem, J; Sachs, L

    1986-01-01

    There are clones of myeloid leukemic cells which are different from normal myeloid cells in that they have become independent of hematopoietic growth factor for cell viability and growth. The ability of these clones to bind three types of hematopoietic growth factors (MGI-1GM = GM-CSF, IL-3 = multi-CSF and MGI-1M = M-CSF = CSF-1) was measured using the method of quantitative absorption at 1 degree C and low pH elution of cell-bound biological activity. Results of binding to normal myeloid and lymphoid cells were similar to those obtained by radioreceptor assays. The results indicate that the number of receptors on different clones of these leukemic cells varied from 0 to 1,300 per cell. The receptors have a high binding affinity. Receptors for different growth factors can be independently expressed in different clones. There was no relationship between expression of receptors for these growth factors and the phenotype of the leukemic cells regarding their ability to be induced to differentiate. The number of receptors on the leukemic cells was lower than on normal mature macrophages. Myeloid leukemic cells induced to differentiate by normal myeloid cell differentiation factor MGI-2 (= DF), or by low doses of actinomycin D or cytosine arabinoside, showed an up-regulation of the number of MGI-1GM and IL-3 receptors. Induction of differentiation of leukemic cells by MGI-2 also induced production and secretion of the growth factor MGI-1GM, and this induced MGI-1GM saturated the up-regulated MGI-1GM receptors. It is suggested that up-regulation of these receptors during differentiation is required for the functioning of differentiated cells. PMID:3023059

  15. Strategies to Reduce Relapse after Allogeneic Hematopoietic Cell Transplantation in Acute Myeloid Leukemia

    PubMed Central

    Mawad, Raya; Lionberger, Jack M.; Pagel, John M.

    2013-01-01

    The incidence of acute myeloid leukemia (AML) is expected to increase in conjunction with our ageing population. Although it is proving to be a heterogeneous disease process, the only treatment with proven survival benefit for poor risk AML remains allogeneic hematopoietic cell transplant. Although this is presumed to be a curative strategy, many patients relapse after transplant, prompting us to examine various ways that we can improve outcomes. These efforts involve every step of AML diagnostics and therapy, including the intricate processes of conditioning, graft manipulation and immunomodulation. The hope is that improvement in these steps will ultimately improve survival and decrease relapse rates for AML patients after transplant. PMID:23456518

  16. Twist-1, a novel regulator of hematopoietic stem cell self-renewal and myeloid lineage development.

    PubMed

    Dong, Cheng-Ya; Liu, Xiao-Yan; Wang, Nan; Wang, Li-Na; Yang, Bin-Xia; Ren, Qian; Liang, Hao-Yue; Ma, Xiao-Tong

    2014-12-01

    Transcription factor Twist-1 plays essential roles in specification and differentiation of mesoderm-derived tissues. Growing evidences now link Twist-1 to the acquisition of stem-cell-like properties. However, the role of Twist-1 in hematopoietic stem cell (HSC) remains largely uncharacterized. We report that Twist-1 is more highly expressed in murine HSC and its expression declines with differentiation. To investigate Twist-1 gene function, retroviral-mediated overexpression or removal experiments are performed. Competitive repopulation studies demonstrate that enforced expression of Twist-1 in HSC-enriched Lin(-) c-Kit(+) Sca-1(+) (LKS) cells results in an increase in the size of the G(0) population, and in their reconstitution ability after the first and a second transplantation. Conversely, removal of Twist-1 in LKS cells impairs their ability to repopulate. In addition, increased Twist-1 expression causes a shift toward production of myeloid cells. Twist-1 transduction in LKS cells activates myeloid lineage-determining factors PU.1 and GATA-1 and downregulates lymphoid factor GATA-3 in vitro, suggesting that Twist-1-mediated myeloid skewing occurs in hematopoietic stem and progenitor cells (HSPCs). These findings indicate that Twist-1 is not only involved in the maintenance of HSC dormancy and self-renewal capacity but also implicated in the myeloid lineage fate choice of HSPCs. Exploration of the underlying mechanisms reveals that Runx1/c-Mpl/Tie2 regulatory pathway could possibly account for the observed effects caused by Twist-1 overexpression. Our study provides the first evidence supporting a role for Twist-1 in hematopoiesis. PMID:25100001

  17. Membrane-bound human SCF/KL promotes in vivo human hematopoietic engraftment and myeloid differentiation

    PubMed Central

    Takagi, Shinsuke; Saito, Yoriko; Hijikata, Atsushi; Tanaka, Satoshi; Watanabe, Takashi; Hasegawa, Takanori; Mochizuki, Shinobu; Kunisawa, Jun; Kiyono, Hiroshi; Koseki, Haruhiko; Ohara, Osamu; Saito, Takashi; Taniguchi, Shuichi; Shultz, Leonard D.

    2012-01-01

    In recent years, advances in the humanized mouse system have led to significantly increased levels of human hematopoietic stem cell (HSC) engraftment. The remaining limitations in human HSC engraftment and function include lymphoid-skewed differentiation and inefficient myeloid development in the recipients. Limited human HSC function may partially be attributed to the inability of the host mouse microenvironment to provide sufficient support to human hematopoiesis. To address this problem, we created membrane-bound human stem cell factor (SCF)/KIT ligand (KL)–expressing NOD/SCID/IL2rgKO (hSCF Tg NSG) mice. hSCF Tg NSG recipients of human HSCs showed higher levels of both human CD45+ cell engraftment and human CD45+CD33+ myeloid development compared with NSG recipients. Expression of hSCF/hKL accelerated the differentiation of the human granulocyte lineage cells in the recipient bone marrow. Human mast cells were identified in bone marrow, spleen, and gastrointestinal tissues of the hSCF Tg NSG recipients. This novel in vivo humanized mouse model demonstrates the essential role of membrane-bound hSCF in human myeloid development. Moreover, the hSCF Tg NSG humanized recipients may facilitate investigation of in vivo differentiation, migration, function, and pathology of human mast cells. PMID:22279057

  18. Clonal evolution of preleukemic hematopoietic stem cells in acute myeloid leukemia.

    PubMed

    Sykes, Stephen M; Kokkaliaris, Konstantinos D; Milsom, Michael D; Levine, Ross L; Majeti, Ravindra

    2015-12-01

    Acute myeloid leukemia (AML) is an aggressive blood cancer that results from an abnormal expansion of uncontrollably proliferating myeloid progenitors that have lost the capacity to differentiate. AML encompasses many genetically distinct subtypes that predominantly develop de novo. However, AML can also arise from premalignant myeloid conditions, such as myelodysplastic syndrome (MDS) and myeloproliferative neoplasms (MPNs), or develop as the result of exposure to genotoxic agents used to treat unrelated malignancies. Although numerous distinct cytogenetic and molecular abnormalities associated with AML were discovered prior to the turn of the millennium, recent advances in whole genome sequencing and global genomic approaches have resulted in an explosion of newly identified molecular abnormalities. However, even with these advances, our understanding of how these mutations contribute to the etiology, pathogenesis, and therapeutic responses of AML remains largely unknown. Recently the International Society for Experimental Hematology (ISEH) hosted a webinar entitled "Clonal Evolution of Pre-Leukemic Hematopoietic Stem Cells (HSCs) in AML" in which two AML mavens, Ross Levine, MD, and Ravindra Majeti, MD, PhD, discussed some of their recent, groundbreaking studies that have shed light on how many of these newly identified mutations contribute to leukemogenesis and therapy resistance in AML. Here, we provide a brief overview of this webinar and discuss the basic scientific and clinical implications of the data presented. PMID:26455528

  19. (Lymph)angiogenic influences on hematopoietic cells in acute myeloid leukemia

    PubMed Central

    Lee, Ji Yoon; Kim, Hee-Je

    2014-01-01

    The purpose of this review is to provide an overview of the effect of (lymph)angiogenic cytokines on hematopoietic cells involved in acute myeloid leukemia (AML). Like angiogenesis, lymphangiogenesis occurs in pathophysiological conditions but not in healthy adults. AML is closely associated with the vasculature system, and the interplay between lymphangiogenic cytokines maintains leukemic blast survival in the bone marrow (BM). Once AML is induced, proangiogenic cytokines function as angiogenic or lymphangiogenic factors and affect hematopoietic cells, including BM-derived immune cells. Simultaneously, the representative cytokines, VEGFs and their receptors are expressed on AML blasts in vascular and osteoblast niches in both the BM and the peripheral circulation. After exposure to (lymph)angiogenic cytokines in leukemogenesis and infiltration, immune cell phenotypes and functions are affected. These dynamic behaviors in the BM reflect the clinical features of AML. In this review, we note the importance of lymphangiogenic factors and their receptors in hematopoietic cells in AML. Understanding the functional characterization of (lymph)angiogenic factors in the BM niche in AML will also be helpful in interrupting the engraftment of leukemic stem cells and for enhancing immune cell function by modulating the tumor microenvironment. PMID:25412683

  20. Enhanced Generation of Myeloid Lineages in Hematopoietic Differentiation from Embryonic Stem Cells by Silencing Transcriptional Repressor Twist-2

    PubMed Central

    Sharabi, Andrew B.; Lee, Sung-Hyung; Goodell, Margaret A.; Huang, Xue F.

    2009-01-01

    Abstract The self-renewal and multilineage differentiation of embryonic stem cells (ESC) is largely governed by transcription factors or repressors. Extensive efforts have focused on elucidating critical factors that control the differentiation of specific cell lineages, for instance, myeloid lineages in hematopoietic development. In this study, we found that Twist-2, a basic helix-loop-helix (bHLH) transcription factor, plays a critical role in inhibiting the differentiation of ESC. Murine ES cells, in which Twist-2 expression is silenced by lentivirally delivered shRNA, exhibit an enhanced formation of primary embryoid bodies (EB) and enhanced differentiation into mesodermally derived hematopoietic colonies. Furthermore, Twist-2 silenced (LV-siTwist-2) ESC display significantly increased generation of myeloid lineages (Gr-1+ and F4/80+ cells) during in vitro hematopoietic differentiation. Treatment with the Toll-like receptor (TLR) 4 ligand synergistically stimulates the generation of primary EB formation as well as of hematopoietic progenitors differentiated from LV-siTwist-2 ES cells. Thus, this study reveals the critical role of the transcriptional repressor Twist-2 in regulating the development of myeloid lineage in hematopoietic differentiation from ESC. This study also suggests a potential strategy for directional differentiation of ESC by inhibiting a transcriptional repressor. PMID:20025523

  1. Functional Niche Competition Between Normal Hematopoietic Stem and Progenitor Cells and Myeloid Leukemia Cells.

    PubMed

    Glait-Santar, Chen; Desmond, Ronan; Feng, Xingmin; Bat, Taha; Chen, Jichun; Heuston, Elisabeth; Mizukawa, Benjamin; Mulloy, James C; Bodine, David M; Larochelle, Andre; Dunbar, Cynthia E

    2015-12-01

    Hematopoietic stem and progenitor cells (HSPCs) reside in a specialized niche that regulates their proliferative capacity and their fate. There is increasing evidence for similar roles of marrow niches on controlling the behavior of leukemic cells; however, whether normal hematopoietic stem cell (HSC) and leukemic cells reside in or functionally compete for the same marrow niche is unclear. We used the mixed lineage leukemia-AF9 (MLL-AF9) murine acute myeloid leukemia (AML) in a competitive repopulation model to investigate whether normal HSPC and leukemic cells functionally compete for the same marrow niches. Irradiated recipient mice were transplanted with fixed numbers of MLL-AF9 cells mixed with increasing doses of normal syngeneic whole bone marrow (WBM) or with purified HSPC (LSK). Survival was significantly increased and leukemic progression was delayed proportional to increasing doses of normal WBM or normal LSK cells in multiple independent experiments, with all doses of WBM or LSK cells studied above the threshold for rapid and complete hematopoietic reconstitution in the absence of leukemia. Confocal microscopy demonstrated nests of either leukemic cells or normal hematopoietic cells but not both in the marrow adjacent to endosteum. Early following transplantation, leukemic cells from animals receiving lower LSK doses were cycling more actively than in those receiving higher doses. These results suggest that normal HSPC and AML cells compete for the same functional niche. Manipulation of the niche could impact on response to antileukemic therapies, and the numbers of normal HSPC could impact on leukemia outcome, informing approaches to cell dose in the context of stem cell transplantation. PMID:26388434

  2. CD34+ hematopoietic precursors are present in human decidua and differentiate into natural killer cells upon interaction with stromal cells.

    PubMed

    Vacca, Paola; Vitale, Chiara; Montaldo, Elisa; Conte, Romana; Cantoni, Claudia; Fulcheri, Ezio; Darretta, Valeria; Moretta, Lorenzo; Mingari, Maria Cristina

    2011-02-01

    Natural killer (NK) cells are the main lymphoid population in the maternal decidua during the first trimester of pregnancy. Decidual NK (dNK) cells display a unique functional profile and play a key role in promoting tissue remodeling, neoangiogenesis, and immune modulation. However, little information exists on their origin and development. Here we discovered CD34(+) hematopoietic precursors in human decidua (dCD34(+)). We show that dCD34(+) cells differ from cord blood- or peripheral blood-derived CD34(+) precursors. The expression of IL-15/IL-2 receptor common β-chain (CD122), IL-7 receptor α-chain (CD127), and mRNA for E4BP4 and ID2 transcription factors suggested that dCD34(+) cells are committed to the NK cell lineage. Moreover, they could undergo in vitro differentiation into functional (i.e., IL-8- and IL-22-producing) CD56(bright)CD16(-)KIR(+/-) NK cells in the presence of growth factors or even upon coculture with decidual stromal cells. Their NK cell commitment was further supported by the failure to undergo myeloid differentiation in the presence of GM-CSF. Our findings strongly suggest that decidual NK cells may directly derive from CD34(+) cell precursors present in the decidua upon specific cellular interactions with components of the decidual microenvironment. PMID:21248224

  3. The preferentially expressed antigen in melanoma (PRAME) inhibits myeloid differentiation in normal hematopoietic and leukemic progenitor cells

    PubMed Central

    Guthrie, Katherine A.; Cummings, Carrie L.; Sabo, Kathleen; Wood, Brent L.; Gooley, Ted; Yang, Taimei; Epping, Mirjam T.; Shou, Yaping; Pogosova-Agadjanyan, Era; Ladne, Paula; Stirewalt, Derek L.; Abkowitz, Janis L.; Radich, Jerald P.

    2009-01-01

    The preferentially expressed antigen in melanoma (PRAME) is expressed in several hematologic malignancies, but either is not expressed or is expressed at only low levels in normal hematopoietic cells, making it a target for cancer therapy. PRAME is a tumor-associated antigen and has been described as a corepressor of retinoic acid signaling in solid tumor cells, but its function in hematopoietic cells is unknown. PRAME mRNA expression increased with chronic myeloid leukemia (CML) disease progression and its detection in late chronic-phase CML patients before tyrosine kinase inhibitor therapy was associated with poorer therapeutic responses and ABL tyrosine kinase domain point mutations. In leukemia cell lines, PRAME protein expression inhibited granulocytic differentiation only in cell lines that differentiate along this lineage after all-trans retinoic acid (ATRA) exposure. Forced PRAME expression in normal hematopoietic progenitors, however, inhibited myeloid differentiation both in the presence and absence of ATRA, and this phenotype was reversed when PRAME was silenced in primary CML progenitors. These observations suggest that PRAME inhibits myeloid differentiation in certain myeloid leukemias, and that its function in these cells is lineage and phenotype dependent. Lastly, these observations suggest that PRAME is a target for both prognostic and therapeutic applications. PMID:19625708

  4. Impact of allogeneic hematopoietic cell transplant in patients with myeloid neoplasms carrying spliceosomal mutations.

    PubMed

    Hamilton, Betty Ky; Visconte, Valeria; Jia, Xuefei; Tabarroki, Ali; Makishima, Hideki; Hasrouni, Edy; Abounader, Donna; Kalaycio, Matt; Sekeres, Mikkael A; Sobecks, Ronald; Duong Liu, Hien; Bolwell, Brian; Maciejewski, Jaroslaw P; Copelan, Edward; Tiu, Ramon V

    2016-06-01

    Molecular predictors of outcome are increasingly important in determining optimal therapy for myeloid neoplasms. Mutations in the spliceosomal genes (U2AF1 and SRSF2) predict for poor outcomes in myelodysplastic syndromes (MDS) and related diseases. We investigated the effect of hematopoietic cell transplant (HCT) on the negative prognostic impact of U2AF1 and SRSF2 mutations. In total, 122 patients with MDS (30%), acute myeloid leukemia (51%), myeloproliferative neoplasms (MPN) (11%), and MDS/MPN (8%) receiving a HCT from 2003 to 2012 were evaluated for mutations in U2AF1 and SRSF2 by direct sequencing. Median time of follow up was 24 months (range 0.46-110). SRSF2 mutations were detected in 11 (10%) patients and U2AF1 in 3 (3%) patients. There were no significant differences in baseline characteristics between mutated and wild-type (WT) patients. Patients carrying SRSF2 and U2AF1 mutations had similar overall survival (P = 0.84), relapse mortality (P = 0.50), and non-relapse mortality (P = 0.72) compared to WT patients. However, taking into account disease status and cytogenetics in a subset of AML patients, SRSF2 and U2AF1 mutations were associated with worse survival (HR 3.71, P = 0.035). Am. J. Hematol. 91:406-409, 2016. © 2016 Wiley Periodicals, Inc. PMID:26799334

  5. Hematopoietic cell crisis: An early stage of evolving myeloid leukemia following radiation exposure

    SciTech Connect

    Seed, T.M.

    1990-01-01

    Under select radiological conditions, chronic radiation exposure elicits a high incidence of myeloproliferative disease, principally myeloid leukemia (ML), in beagles. Previously we demonstrated that for full ML expression, a four-stage preclinical sequence is required, namely (1) suppression, (2) recovery, (3) accommodation, and (4) preleukemic transition. Within this pathological sequence, a critical early event has been identified as the acquisition of radioresistance by hematopoietic progenitors that serves to mediate a newfound regenerative hematopoietic capacity. As such, this event sets the stage'' for preleukemic progression by initiating progression from preclinical phase 1 to 2. Due to the nature of target cell suppression, the induction of crisis, and the outgrowth of progenitors with altered phenotypes, this preleukemic event resembles the immortalization'' step of the in vitro transformation sequence following induction with either physical and chemical carcinogens. The radiological, temporal, and biological dictates governing this event have been extensively evaluated and will be discussed in light of their role in the induction and progression of chronic radiation leukemia. 35 refs., 2 tabs.

  6. Agitation increases expansion of cord blood hematopoietic cells and promotes their differentiation into myeloid lineage.

    PubMed

    Hosseinizand, Hasti; Ebrahimi, Marzieh; Abdekhodaie, Mohammad J

    2016-08-01

    Mechanical stress caused by agitation is one of the factors that can affect hematopoietic stem cell expansion in suspension bioreactors. Therefore, we have investigated the effects of agitation on umbilical cord blood hematopoietic stem cell (UCB-HSC) growth and differentiation. A comparison was made between various agitation rates (20, 40 and 60 rpm) in spinner-flask and cells cultured in glass petri dish as a static culture. Moreover, the fluid dynamic at various agitation rates of spinner-flask was analyzed to determine shear stress. The spinner-flask contained a rotational moving mixer with glass ball and was kept in tissue culture incubator. To reduce consumption of cytokines, UCB-serum was used which widely decreased the costs. Our results determined that, agitation rate at 40 rpm promoted UCB-HSCs expansion and their colony forming potential. Myeloid progenitors were the main type of cells at 40 rpm agitation rate. The results of glucose consumption and lactic acid production were in complete agreement with colony assay and expansion data and indicated the superiority of culture in spinner-flask when agitated at 40 rpm over to other agitation speeds and also static culture. Cell viability and colony count was affected by changing the agitation speed. We assume that changes in cell growth resulted from the effect of shear stress directly on cell viability, and indirectly on signaling pathways that influence the cells to differentiate. PMID:26264594

  7. EVI1 and MDS1/EVI1 Expression During Primary Human Hematopoietic Progenitor Cell Differentiation into Various Myeloid Lineages

    PubMed Central

    Steinleitner, Katarina; Rampetsreiter, Paulina; Köffel, Rene; Ramanathan, Gajalakshmi; Mannhalter, Christine; Strobl, Herbert; Wieser, Rotraud

    2012-01-01

    Background and Aim Overexpression of ecotropic viral integration site 1 (EVI1) is associated with aggressive disease in myeloid leukemia. We therefore studied its expression and function in cluster of differentiation 34 positive (CD 34+) primary human hematopoietic progenitor cells. Materials and Methods CD34+ cells were differentiated into various myeloid lineages using appropriate cytokines. EVI1 expression was measured by quantitative real time reverse transcriptase polymerase chain reaction (qRT-PCR) and intranuclear fluorescence activated cell sorting (FACS). Experimental manipulation of EVI1 levels was achieved using retroviral infection. Results EVI1 mRNA and its variant myelodysplastic syndrome 1 (MDS1)/EVI1, which gives rise to a partially antagonistic protein, were detectable in CD34+ cells, but their levels declined rapidly during differentiation into the granulocytic, monocytic, dendritic, erythroid, and megakaryocytic lineages. Similarly, EVI1 protein levels decreased during myeloid differentiation. Attempts to experimentally express EVI1 in CD34+ and U937 cells indicated that ectopic expression of EVI1 may cause growth arrest, apoptosis and/or senescence of human hematopoietic cells. Conclusion EVI1 is expressed in human hematopoietic progenitor cells, but is down-regulated during differentiation. Ectopic expression of EVI1 may activate cellular safeguards against oncogene activation. PMID:23155256

  8. PRIMITIVE ADULT HEMATOPOIETIC STEM CELLS CAN FUNCTION AS OSTEOBLAST PRECURSORS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Osteoblasts are continually recruited from stem cell pools to maintain bone. Although their immediate precursor is a plastic-adherent mesenchymal stem cell able to generate tissues other than bone, increasing evidence suggests the existence of a more primitive cell that can differentiate to both hem...

  9. Myeloid/Microglial Driven Autologous Hematopoietic Stem Cell Gene Therapy Corrects a Neuronopathic Lysosomal Disease

    PubMed Central

    Sergijenko, Ana; Langford-Smith, Alexander; Liao, Ai Y; Pickford, Claire E; McDermott, John; Nowinski, Gabriel; Langford-Smith, Kia J; Merry, Catherine LR; Jones, Simon A; Wraith, J Edmond; Wynn, Robert F; Wilkinson, Fiona L; Bigger, Brian W

    2013-01-01

    Mucopolysaccharidosis type IIIA (MPSIIIA) is a lysosomal storage disorder caused by mutations in N-sulfoglucosamine sulfohydrolase (SGSH), resulting in heparan sulfate (HS) accumulation and progressive neurodegeneration. There are no treatments. We previously demonstrated improved neuropathology in MPSIIIA mice using lentiviral vectors (LVs) overexpressing SGSH in wild-type (WT) hematopoietic stem cell (HSC) transplants (HSCTs), achieved via donor monocyte/microglial engraftment in the brain. However, neurological disease was not corrected using LVs in autologous MPSIIIA HSCTs. To improve brain expression via monocyte/microglial specificity, LVs expressing enhanced green fluorescent protein (eGFP) under ubiquitous phosphoglycerate kinase (PGK) or myeloid-specific promoters were compared in transplanted HSCs. LV-CD11b-GFP gave significantly higher monocyte/B-cell eGFP expression than LV-PGK-GFP or LV-CD18-GFP after 6 months. Subsequently, autologous MPSIIIA HSCs were transduced with either LV-PGK-coSGSH or LV-CD11b-coSGSH vectors expressing codon-optimized SGSH and transplanted into MPSIIIA mice. Eight months after HSCT, LV-PGK-coSGSH vectors produced bone marrow SGSH (576% normal activity) similar to LV-CD11b-coSGSH (473%), but LV-CD11b-coSGSH had significantly higher brain expression (11 versus 7%), demonstrating improved brain specificity. LV-CD11b-coSGSH normalized MPSIIIA behavior, brain HS, GM2 ganglioside, and neuroinflammation to WT levels, whereas LV-PGK-coSGSH partly corrected neuropathology but not behavior. We demonstrate compelling evidence of neurological disease correction using autologous myeloid driven lentiviral-HSC gene therapy in MPSIIIA mice. PMID:23748415

  10. Therapy-related myeloid neoplasms after autologous hematopoietic stem cell transplantation in lymphoma patients

    PubMed Central

    Akhtari, Mojtaba; Bhatt, Vijaya Raj; Tandra, Pavan Kumar; Krishnamurthy, Jairam; Horstman, Heidi; Dreessen, Amy; Chen, Pei Xian; Armitage, James O

    2013-01-01

    Lymphoma patients treated with autologous transplantation (ASCT) live an increasingly long life with the recent advancement in therapeutic modalities. This has resulted in an increase in the incidence of therapy-related myeloid neoplasms (t-MN), which is one of the leading causes of non-relapse mortality. Several observational studies have linked the development of t-MN after ASCT with the intensity and frequency of chemotherapy, particularly alkylating agents, use of total body irradiation (TBI), and peripheral blood progenitor cells. In addition, role of genetic factors is increasingly being identified. It is postulated that the use of chemotherapy prior to ASCT results in DNA damage of progenitor cells, mitochondrial dysfunction, and altered gene expression related to DNA repair, metabolism as well as hematopoietic regulation. Cytogenetic studies have shown the presence of abnormalities in the peripheral blood progenitor cells prior to ASCT. It is, therefore, likely that the reinfusion of peripheral blood progenitor cells, proliferative stress on infused progenitor cells during hematopoietic regeneration and associated telomere shortening ultimately result in clonal hematopoiesis and blastic transformation. Cytopenias, myelodysplasia, or cytogenetic abnormalities are common and can be transient after ASCT; therefore, only when present together, they do confirm the diagnosis of t-MN. Attempts to reduce the occurrence of t-MN should be directed toward minimizing the exposure to the identified risk factors. Although the median survival is few months to less than a year, studies have shown the promising role of allogeneic transplantation in select young t-MN patients without high-risk cytogenetics. In this review we will explain the recent findings in the field of t-MN in lymphoma patients that have implications for identifying the molecular and genetic mechanisms of leukemogenesis and discuss potential strategies to reduce the risk of t-MN in this patient

  11. Impact of prior imatinib mesylate on the outcome of hematopoietic cell transplantation for chronic myeloid leukemia

    PubMed Central

    Kukreja, Manisha; Wang, Tao; Giralt, Sergio A.; Szer, Jeffrey; Arora, Mukta; Woolfrey, Ann E.; Cervantes, Francisco; Champlin, Richard E.; Gale, Robert Peter; Halter, Joerg; Keating, Armand; Marks, David I.; McCarthy, Philip L.; Olavarria, Eduardo; Stadtmauer, Edward A.; Abecasis, Manuel; Gupta, Vikas; Khoury, H. Jean; George, Biju; Hale, Gregory A.; Liesveld, Jane L.; Rizzieri, David A.; Antin, Joseph H.; Bolwell, Brian J.; Carabasi, Matthew H.; Copelan, Edward; Ilhan, Osman; Litzow, Mark R.; Schouten, Harold C.; Zander, Axel R.; Horowitz, Mary M.; Maziarz, Richard T.

    2008-01-01

    Imatinib mesylate (IM, Gleevec) has largely supplanted allogeneic hematopoietic cell transplantation (HCT) as first line therapy for chronic myeloid leukemia (CML). Nevertheless, many people with CML eventually undergo HCT, raising the question of whether prior IM therapy impacts HCT success. Data from the Center for International Blood and Marrow Transplant Research on 409 subjects treated with IM before HCT (IM+) and 900 subjects who did not receive IM before HCT (IM−) were analyzed. Among patients in first chronic phase, IM therapy before HCT was associated with better survival but no statistically significant differences in treatment-related mortality, relapse, and leukemia-free survival. Better HLA-matched donors, use of bone marrow, and transplantation within one year of diagnosis were also associated with better survival. A matched-pairs analysis was performed and confirmed a higher survival rate among first chronic phase patients receiving IM. Among patients transplanted with advanced CML, use of IM before HCT was not associated with treatment-related mortality, relapse, leukemia-free survival, or survival. Acute graft-versus-host disease rates were similar between IM+ and IM− groups regardless of leukemia phase. These results should be reassuring to patients receiving IM before HCT. PMID:18664621

  12. Reduced-intensity conditioning allogeneic hematopoietic-cell transplantation for older patients with acute myeloid leukemia

    PubMed Central

    Goyal, Gaurav; Gundabolu, Krishna; Vallabhajosyula, Saraschandra; Silberstein, Peter T.; Bhatt, Vijaya Raj

    2016-01-01

    Elderly patients (>60 years) with acute myeloid leukemia have a poor prognosis with a chemotherapy-alone approach. Allogeneic hematopoietic-cell transplantation (HCT) can improve overall survival (OS). However, myeloablative regimens can have unacceptably high transplant-related mortality (TRM) in an unselected group of older patients. Reduced-intensity conditioning (RIC) or nonmyeloablative (NMA) conditioning regimens preserve the graft-versus-leukemia effects but reduce TRM. NMA regimens result in minimal cytopenia and may not require stem cell support for restoring hematopoiesis. RIC regimens, intermediate in intensity between NMA and myeloablative regimens, can cause prolonged myelosuppresion and usually require stem cell support. A few retrospective and prospective studies suggest a possibility of lower risk of relapse with myeloablative HCT in fit older patients with lower HCT comorbidity index; however, RIC and NMA HCTs have an important role in less-fit patients and those with significant comorbidities because of lower TRM. Whether early tapering of immunosuppression, monitoring of minimal residual disease, and post-transplant maintenance therapy can improve the outcomes of RIC and NMA HCT in elderly patients will require prospective trials. PMID:27247754

  13. Reduced-intensity conditioning allogeneic hematopoietic-cell transplantation for older patients with acute myeloid leukemia.

    PubMed

    Goyal, Gaurav; Gundabolu, Krishna; Vallabhajosyula, Saraschandra; Silberstein, Peter T; Bhatt, Vijaya Raj

    2016-06-01

    Elderly patients (>60 years) with acute myeloid leukemia have a poor prognosis with a chemotherapy-alone approach. Allogeneic hematopoietic-cell transplantation (HCT) can improve overall survival (OS). However, myeloablative regimens can have unacceptably high transplant-related mortality (TRM) in an unselected group of older patients. Reduced-intensity conditioning (RIC) or nonmyeloablative (NMA) conditioning regimens preserve the graft-versus-leukemia effects but reduce TRM. NMA regimens result in minimal cytopenia and may not require stem cell support for restoring hematopoiesis. RIC regimens, intermediate in intensity between NMA and myeloablative regimens, can cause prolonged myelosuppresion and usually require stem cell support. A few retrospective and prospective studies suggest a possibility of lower risk of relapse with myeloablative HCT in fit older patients with lower HCT comorbidity index; however, RIC and NMA HCTs have an important role in less-fit patients and those with significant comorbidities because of lower TRM. Whether early tapering of immunosuppression, monitoring of minimal residual disease, and post-transplant maintenance therapy can improve the outcomes of RIC and NMA HCT in elderly patients will require prospective trials. PMID:27247754

  14. CD117 expression in gammopathies is associated with an altered maturation of the myeloid and lymphoid hematopoietic cell compartments and favorable disease features

    PubMed Central

    Schmidt-Hieber, Martin; Pérez-Andrés, Martin; Paiva, Bruno; Flores-Montero, Juan; Perez, Jose J.; Gutierrez, Norma C.; Vidriales, Maria-Belen; Matarraz, Sergio; San Miguel, Jesus F.; Orfao, Alberto

    2011-01-01

    Aberrant CD117 expression is associated with a favorable outcome in multiple myeloma. We analyzed 106 patients with symptomatic multiple myeloma (n=50), smoldering multiple myeloma (n=38) and monoclonal gammopathy of undetermined significance (n=18) to elucidate biological features of CD117+ versus CD117− monoclonal gammopathies. CD117+ (mono)clonal plasma cells were detected in 30% symptomatic multiple myeloma, 45% smoldering multiple myeloma and 72% monoclonal gammopathy of undetermined significance patients. CD117 expression was associated with higher percentages of normal bone marrow plasma cells, CD117+ myeloid precursors and CD38+ B lymphocytes in all monoclonal gammopathies. Conversely, the number of bone marrow CD34+ myeloid cells and peripheral blood neutrophils was reduced among CD117+ multiple myeloma but not monoclonal gammopathy of undetermined significance patients. CD117 expression by (mono)clonal plasma cells is associated with uniquely altered patterns of production of hematopoietic bone marrow cells with decreased peripheral blood neutrophil counts and persistence of normal residual bone marrow plasma cells. PMID:20971816

  15. Extracellular vesicle miR-7977 is involved in hematopoietic dysfunction of mesenchymal stromal cells via poly(rC) binding protein 1 reduction in myeloid neoplasms

    PubMed Central

    Horiguchi, Hiroto; Kobune, Masayoshi; Kikuchi, Shohei; Yoshida, Masahiro; Murata, Masaki; Murase, Kazuyuki; Iyama, Satoshi; Takada, Kohichi; Sato, Tsutomu; Ono, Kaoru; Hashimoto, Akari; Tatekoshi, Ayumi; Kamihara, Yusuke; Kawano, Yutaka; Miyanishi, Koji; Sawada, Norimasa; Kato, Junji

    2016-01-01

    The failure of normal hematopoiesis is observed in myeloid neoplasms. However, the precise mechanisms governing the replacement of normal hematopoietic stem cells in their niche by myeloid neoplasm stem cells have not yet been clarified. Primary acute myeloid leukemia and myelodysplastic syndrome cells induced aberrant expression of multiple hematopoietic factors including Jagged-1, stem cell factor and angiopoietin-1 in mesenchymal stem cells even in non-contact conditions, and this abnormality was reverted by extracellular vesicle inhibition. Importantly, the transfer of myeloid neoplasm-derived extracellular vesicles reduced the hematopoietic supportive capacity of mesenchymal stem cells. Analysis of extracellular vesicle microRNA indicated that several species, including miR-7977 from acute myeloid leukemia cells, were higher than those from normal CD34+ cells. Remarkably, the copy number of miR-7977 in bone marrow interstitial fluid was elevated not only in acute myeloid leukemia, but also in myelodysplastic syndrome, as compared with lymphoma without bone marrow localization. The transfection of the miR-7977 mimic reduced the expression of the posttranscriptional regulator, poly(rC) binding protein 1, in mesenchymal stem cells. Moreover, the miR-7977 mimic induced aberrant reduction of hematopoietic growth factors in mesenchymal stem cells, resulting in decreased hematopoietic-supporting capacity of bone marrow CD34+ cells. Furthermore, the reduction of hematopoietic growth factors including Jagged-1, stem cell factor and angiopoietin-1 were reverted by target protection of poly(rC) binding protein 1, suggesting that poly(rC) binding protein 1 could be involved in the stabilization of several growth factors. Thus, miR-7977 in extracellular vesicles may be a critical factor that induces failure of normal hematopoiesis via poly(rC) binding protein 1 suppression. PMID:26802051

  16. Adoptive precursor cell therapy to enhance immune reconstitution after hematopoietic stem cell transplantation in mouse and man

    PubMed Central

    Holland, Amanda M.; Zakrzewski, Johannes L.; Goldberg, Gabrielle L.; Ghosh, Arnab

    2016-01-01

    Hematopoietic stem cell transplantation is a curative therapy for hematological malignancies. T cell deficiency following transplantation is a major cause of morbidity and mortality. In this review, we discuss adoptive transfer of committed precursor cells to enhance T cell reconstitution and improve overall prognosis after transplantation. PMID:19015856

  17. Stem cell biology is population biology: differentiation of hematopoietic multipotent progenitors to common lymphoid and myeloid progenitors

    PubMed Central

    2013-01-01

    The hematopoietic stem cell (HSC) system is a demand control system, with the demand coming from the organism, since the products of the common myeloid and lymphoid progenitor (CMP, CLP respectively) cells are essential for activity and defense against disease. We show how ideas from population biology (combining population dynamics and evolutionary considerations) can illuminate the feedback control of the HSC system by the fully differentiated products, which has recently been verified experimentally. We develop models for the penultimate differentiation of HSC Multipotent Progenitors (MPPs) into CLP and CMP and introduce two concepts from population biology into stem cell biology. The first concept is the Multipotent Progenitor Commitment Response (MPCR) which is the probability that a multipotent progenitor cell follows a CLP route rather than a CMP route. The second concept is the link between the MPCR and a measure of Darwinian fitness associated with organismal performance and the levels of differentiated lymphoid and myeloid cells. We show that many MPCRs are consistent with homeostasis, but that they will lead to different dynamics of cells and signals following a wound or injury and thus have different consequences for Darwinian fitness. We show how coupling considerations of life history to dynamics of the HSC system and its products allows one to compute the selective pressures on cellular processes. We discuss ways that this framework can be used and extended. PMID:23327512

  18. PSTPIP2 deficiency in mice causes osteopenia and increased differentiation of multipotent myeloid precursors into osteoclasts

    PubMed Central

    Nacu, Viorel; Charles, Julia F.; Henne, William M.; McMahon, Harvey T.; Nandi, Sayan; Ketchum, Halley; Harris, Renee; Nakamura, Mary C.

    2012-01-01

    Missense mutations that reduce or abrogate myeloid cell expression of the F-BAR domain protein, proline serine threonine phosphatase-interacting protein 2 (PSTPIP2), lead to autoinflammatory disease involving extramedullary hematopoiesis, skin and bone lesions. However, little is known about how PSTPIP2 regulates osteoclast development. Here we examined how PSTPIP2 deficiency causes osteopenia and bone lesions, using the mouse PSTPIP2 mutations, cmo, which fails to express PSTPIP2 and Lupo, in which PSTPIP2 is dysfunctional. In both models, serum levels of the pro-osteoclastogenic factor, MIP-1α, were elevated and CSF-1 receptor (CSF-1R)–dependent production of MIP-1α by macrophages was increased. Treatment of cmo mice with a dual specificity CSF-1R and c-Kit inhibitor, PLX3397, decreased circulating MIP-1α and ameliorated the extramedullary hematopoiesis, inflammation, and osteopenia, demonstrating that aberrant myelopoiesis drives disease. Purified osteoclast precursors from PSTPIP2-deficient mice exhibit increased osteoclastogenesis in vitro and were used to probe the structural requirements for PSTPIP2 suppression of osteoclast development. PSTPIP2 tyrosine phosphorylation and a functional F-BAR domain were essential for PSTPIP2 inhibition of TRAP expression and osteoclast precursor fusion, whereas interaction with PEST-type phosphatases was only required for suppression of TRAP expression. Thus, PSTPIP2 acts as a negative feedback regulator of CSF-1R signaling to suppress inflammation and osteoclastogenesis. PMID:22923495

  19. Heterogeneity of Clonal Expansion and Maturation-Linked Mutation Acquisition in Hematopoietic Progenitors in Human Acute Myeloid Leukemia

    PubMed Central

    Walter, Roland B.; Laszlo, George S.; Lionberger, Jack M.; Pollard, Jessica A.; Harrington, Kimberly H.; Gudgeon, Chelsea J.; Othus, Megan; Rafii, Shahin; Meshinchi, Soheil; Appelbaum, Frederick R.; Bernstein, Irwin D.

    2014-01-01

    Recent technological advances led to an appreciation of the genetic complexity of human acute myeloid leukemia (AML) but underlying progenitor cells remain poorly understood because their rarity precludes direct study. We developed a co-culture method integrating hypoxia, aryl hydrocarbon receptor inhibition, and micro-environmental support via human endothelial cells to isolate these cells. X-chromosome inactivation studies of the least mature precursors derived following prolonged culture of CD34+/CD33− cells revealed polyclonal growth in highly curable AMLs, suggesting mutations necessary for clonal expansion were acquired in more mature progenitors. Consistently, in core-binding factor (CBF) leukemias with known complementing mutations, immature precursors derived following prolonged culture of CD34+/CD33− cells harbored neither mutation or the CBF mutation alone, whereas more mature precursors often carried both mutations. These results were in contrast to those with leukemias with poor prognosis that showed clonal dominance in the least mature precursors. These data indicate heterogeneity among progenitors in human AML that may have prognostic and therapeutic implications. PMID:24721792

  20. Pretransplant NPM1 MRD levels predict outcome after allogeneic hematopoietic stem cell transplantation in patients with acute myeloid leukemia.

    PubMed

    Kayser, S; Benner, A; Thiede, C; Martens, U; Huber, J; Stadtherr, P; Janssen, J W G; Röllig, C; Uppenkamp, M J; Bochtler, T; Hegenbart, U; Ehninger, G; Ho, A D; Dreger, P; Krämer, A

    2016-01-01

    The objective was to evaluate the prognostic impact of pre-transplant minimal residual disease (MRD) as determined by real-time quantitative polymerase chain reaction in 67 adult NPM1-mutated acute myeloid leukemia patients receiving allogeneic hematopoietic stem cell transplantation (HSCT). Twenty-eight of the 67 patients had a FLT3-ITD (42%). Median age at transplantation was 54.7 years, median follow-up for survival from time of allografting was 4.9 years. At transplantation, 31 patients were in first, 20 in second complete remission (CR) and 16 had refractory disease (RD). Pre-transplant NPM1 MRD levels were measured in 39 CR patients. Overall survival (OS) for patients transplanted in CR was significantly longer as compared to patients with RD (P=0.004), irrespective of whether the patients were transplanted in first or second CR (P=0.74). There was a highly significant difference in OS after allogeneic HSCT between pre-transplant MRD-positive and MRD-negative patients (estimated 5-year OS rates of 40 vs 89%; P=0.007). Multivariable analyses on time to relapse and OS revealed pre-transplant NPM1 MRD levels >1% as an independent prognostic factor for poor survival after allogeneic HSCT, whereas FLT3-ITD had no impact. Notably, outcome of patients with pre-transplant NPM1 MRD positivity >1% was as poor as that of patients transplanted with RD. PMID:27471865

  1. OBESITY DOES NOT PRECLUDE SAFE AND EFFECTIVE MYELOABLATIVE HEMATOPOIETIC CELL TRANSPLANTATION (HCT) FOR ACUTE MYELOID LEUKEMIA (AML) IN ADULTS

    PubMed Central

    Navarro, Willis H.; Agovi, Manza-A.; Logan, Brent R.; Ballen, Karen; Bolwell, Brian J.; Frangoul, Haydar; Gupta, Vikas; Hahn, Theresa; Ho, Vincent T.; Juckett, Mark; Lazarus, Hillard M.; Litzow, Mark R.; Liesveld, Jane L.; Moreb, Jan S.; Marks, David I.; McCarthy, Philip L.; Pasquini, Marcelo C.; Rizzo, J. Douglas

    2010-01-01

    The incidence of excessive adiposity is increasing worldwide and is associated with numerous adverse health outcomes. We compared outcomes by body mass index (BMI) for adult patients with acute myeloid leukemia (AML) who underwent autologous (auto, n=373), related donor (RD, n=2041), or unrelated donor (URD, n=1801) allogeneic myeloablative hematopoietic cell transplantation (HCT) using marrow or peripheral blood stem cells reported to the Center for International Blood and Marrow Transplant Research (CIBMTR) from 1995-2004. Four weight groups by BMI (kg/m2) were defined: underweight < 18; normal 18 – 25; overweight >25 – 30; and obese > 30. Multivariable analysis referenced to the normal weight group showed an increased risk of death for underweight patients in the RD group (RR, 1.92; 95% CI, 1.28-2.89; P = 0.002) but not in the URD group. There were no other differences in outcomes among the other weight groups within the other HCT groups. Overweight and obese patients enjoyed a modest decrease in relapse incidence, though this did not translate into a survival benefit. Small numbers of patients limit the ability to better characterize the adverse outcomes seen in the underweight RD but not the underweight URD allogeneic HCT patients. Obesity alone should not be considered a barrier to HCT. PMID:20412867

  2. Mobilization of CD34+CD38- hematopoietic stem cells after priming in acute myeloid leukemia

    PubMed Central

    Plesa, Adriana; Chelghoum, Youcef; Mattei, Eve; Labussière, Hélène; Elhamri, Mohamed; Cannas, Giovanna; Morisset, Stéphane; Tagoug, Inès; Michallet, Mauricette; Dumontet, Charles; Thomas, Xavier

    2013-01-01

    AIM: To evaluate quantitatively and qualitatively the different CD34+ cell subsets after priming by chemotherapy granulocyte colony-stimulating factor (± G-CSF) in patients with acute myeloid leukemia. METHODS: Peripheral blood and bone marrow samples were harvested in 8 acute myeloid leukemia patients during and after induction chemotherapy. The CD34/CD38 cell profile was analyzed by multi-parameter flow cytometry. Adhesion profile was made using CXC chemokine receptor 4 (CXCR4) (CD184), VLA-4 (CD49d/CD29) and CD47. RESULTS: Chemotherapy ± G-CSF mobilized immature cells (CD34+CD38− population), while the more mature cells (CD34+CD38low and CD34+CD38+ populations) decreased progressively after treatment. Circulating CD34+ cells tended to be more sensitive to chemotherapy after priming with G-CSF. CD34+ cell mobilization was correlated with a gradual increase in CXCR4 and CD47 expression, suggesting a role in cell protection and the capacity of homing back to the marrow. CONCLUSION: Chemotherapy ± G-CSF mobilizes into the circulation CD34+ bone marrow cells, of which, the immature CD34+CD38– cell population. Further manipulations of these interactions may be a means with which to control the trafficking of leukemia stem cells to improve patients’ outcomes. PMID:24179607

  3. Promotion of Expansion and Differentiation of Hematopoietic Stem Cells by Interleukin-27 into Myeloid Progenitors to Control Infection in Emergency Myelopoiesis

    PubMed Central

    Furusawa, Jun-ichi; Mizoguchi, Izuru; Chiba, Yukino; Hisada, Masayuki; Kobayashi, Fumie; Yoshida, Hiroki; Nakae, Susumu; Tsuchida, Akihiko; Matsumoto, Tetsuya; Ema, Hideo; Mizuguchi, Junichiro; Yoshimoto, Takayuki

    2016-01-01

    Emergency myelopoiesis is inflammation-induced hematopoiesis to replenish myeloid cells in the periphery, which is critical to control the infection with pathogens. Previously, pro-inflammatory cytokines such as interferon (IFN)-α and IFN-γ were demonstrated to play a critical role in the expansion of hematopoietic stem cells (HSCs) and myeloid progenitors, leading to production of mature myeloid cells, although their inhibitory effects on hematopoiesis were also reported. Therefore, the molecular mechanism of emergency myelopoiesis during infection remains incompletely understood. Here, we clarify that one of the interleukin (IL)-6/IL-12 family cytokines, IL-27, plays an important role in the emergency myelopoiesis. Among various types of hematopoietic cells in bone marrow, IL-27 predominantly and continuously promoted the expansion of only Lineage−Sca-1+c-Kit+ (LSK) cells, especially long-term repopulating HSCs and myeloid-restricted progenitor cells with long-term repopulating activity, and the differentiation into myeloid progenitors in synergy with stem cell factor. These progenitors expressed myeloid transcription factors such as Spi1, Gfi1, and Cebpa/b through activation of signal transducer and activator of transcription 1 and 3, and had enhanced potential to differentiate into migratory dendritic cells (DCs), neutrophils, and mast cells, and less so into macrophages, and basophils, but not into plasmacytoid DCs, conventional DCs, T cells, and B cells. Among various cytokines, IL-27 in synergy with the stem cell factor had the strongest ability to augment the expansion of LSK cells and their differentiation into myeloid progenitors retaining the LSK phenotype over a long period of time. The experiments using mice deficient for one of IL-27 receptor subunits, WSX-1, and IFN-γ revealed that the blood stage of malaria infection enhanced IL-27 expression through IFN-γ production, and the IL-27 then promoted the expansion of LSK cells, differentiating and

  4. Recruitment of myeloid but not endothelial precursor cells facilitates tumor re-growth after local irradiation

    PubMed Central

    Kozin, Sergey V.; Kamoun, Walid S.; Huang, Yuhui; Dawson, Michelle R.; Jain, Rakesh K.; Duda, Dan G.

    2010-01-01

    Tumor neovascularization and growth may be promoted by recruitment of bone marrow-derived cells (BMDCs), which include endothelial precursor cells (EPCs) and “vascular modulatory” myelomonocytic (CD11b+) cells. BMDCs may also drive tumor re-growth after certain chemotherapeutic and vascular disruption treatments. In this study, we evaluated the role of BMDC recruitment in breast and lung carcinoma xenograft models after local irradiation (LI). We depleted the bone marrow by including whole body irradiation (WBI) of 6Gy as part of a total tumor dose of 21Gy, and compared the growth delay with the one achieved after LI of 21Gy. In both models, including WBI induced longer tumor growth delays. Moreover, including WBI increased lung tumor control probability by LI. Exogenous delivery of BMDCs from radiation-naïve donors partially abrogated the WBI effect. Myeloid BMDCs, primarily macrophages, rapidly accumulated in tumors after LI. Intratumoral expression of SDF-1α, a chemokine that promotes tissue retention of BMDCs, was noted 2 days after LI. Conversely, treatment with an inhibitor of SDF-1α receptor CXCR4 (AMD3100) with LI significantly delayed tumor re-growth. However, when administered starting from 5 days post-LI, AMD3100 treatment was ineffective. Lastly, with restorative bone marrow transplantation of Tie2-GFP-labeled BMDC population we observed an increased number of monocytes but not EPCs in tumors that recurred following LI. Our results suggest that an increase in intratumoral SDF-1α triggered by local irradiation recruits myelomonocyte/macrophage which promote tumor re-growth. PMID:20631066

  5. Runx1 Regulates Myeloid Precursor Differentiation Into Osteoclasts Without Affecting Differentiation Into Antigen Presenting or Phagocytic Cells in Both Males and Females.

    PubMed

    Paglia, David N; Yang, Xiaochuan; Kalinowski, Judith; Jastrzebski, Sandra; Drissi, Hicham; Lorenzo, Joseph

    2016-08-01

    Runt-related transcription factor 1 (Runx1), a master regulator of hematopoiesis, is expressed in preosteoclasts. Previously we evaluated the bone phenotype of CD11b-Cre Runx1(fl/fl) mice and demonstrated enhanced osteoclasts and decreased bone mass in males. However, an assessment of the effects of Runx1 deletion in female osteoclast precursors was impossible with this model. Moreover, the role of Runx1 in myeloid cell differentiation into other lineages is unknown. Therefore, we generated LysM-Cre Runx1(fl/fl) mice, which delete Runx1 equally (∼80% deletion) in myeloid precursor cells from both sexes and examined the capacity of these cells to differentiate into osteoclasts and phagocytic and antigen-presenting cells. Both female and male LysM-Cre Runx1(fl/fl) mice had decreased trabecular bone mass (72% decrease in bone volume fraction) and increased osteoclast number (2-3 times) (P < .05) without alteration of osteoblast histomorphometric indices. We also demonstrated that loss of Runx1 in pluripotential myeloid precursors with LysM-Cre did not alter the number of myeloid precursor cells in bone marrow or their ability to differentiate into phagocytizing or antigen-presenting cells. This study demonstrates that abrogation of Runx1 in multipotential myeloid precursor cells significantly and specifically enhanced the ability of receptor activator of nuclear factor-κB ligand to stimulate osteoclast formation and fusion in female and male mice without affecting other myeloid cell fates. In turn, increased osteoclast activity in LysM-Cre Runx1(fl/fl) mice likely contributed to a decrease in bone mass. These dramatic effects were not due to increased osteoclast precursors in the deleted mutants and argue that inhibition of Runx1 in multipotential myeloid precursor cells is important for osteoclast formation and function. PMID:27267711

  6. [The efficacy of sorafenib to prevent relapse in patients with FLT3-ITD mutation positive acute myeloid leukemia after allogeneic hematopoietic stem cell transplantation].

    PubMed

    Zu, Y L; Zhang, Y L; Zhou, J; Han, L J; Zhao, H F; Gui, R R; Hou, Y J; Song, Y P

    2016-08-01

    To study the efficacy of sorafenib to prevent relapse in patients with FLT3-ITD mutation positive acute myeloid leukemia (AML) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). A total of 7 cases with FLT3-ITD positive AML have received allo-HSCT in our department from May 2013 to January 2015. Six cases were administrated with sorafenib after hematopoietic reconstruction. Another patient relapsed on day 192 past allo-HSCT, then she started to use sorafenib after remission of re-induction regimens. Five patients survived. The median progression free survival was 280(126-366)day. This study suggests that sorafenib might prevent relapse past allo-HSCT and improve survival in patients with FLT3-ITD positive AML. PMID:27480560

  7. Caffeine affects the biological responses of human hematopoietic cells of myeloid lineage via downregulation of the mTOR pathway and xanthine oxidase activity

    PubMed Central

    Abooali, Maryam; Yasinska, Inna M.; Casely-Hayford, Maxwell A.; Berger, Steffen M.; Fasler-Kan, Elizaveta; Sumbayev, Vadim V.

    2015-01-01

    Correction of human myeloid cell function is crucial for the prevention of inflammatory and allergic reactions as well as leukaemia progression. Caffeine, a naturally occurring food component, is known to display anti-inflammatory effects which have previously been ascribed largely to its inhibitory actions on phosphodiesterase. However, more recent studies suggest an additional role in affecting the activity of the mammalian target of rapamycin (mTOR), a master regulator of myeloid cell translational pathways, although detailed molecular events underlying its mode of action have not been elucidated. Here, we report the cellular uptake of caffeine, without metabolisation, by healthy and malignant hematopoietic myeloid cells including monocytes, basophils and primary acute myeloid leukaemia mononuclear blasts. Unmodified caffeine downregulated mTOR signalling, which affected glycolysis and the release of pro-inflammatory/pro-angiogenic cytokines as well as other inflammatory mediators. In monocytes, the effects of caffeine were potentiated by its ability to inhibit xanthine oxidase, an enzyme which plays a central role in human purine catabolism by generating uric acid. In basophils, caffeine also increased intracellular cyclic adenosine monophosphate (cAMP) levels which further enhanced its inhibitory action on mTOR. These results demonstrate an important mode of pharmacological action of caffeine with potentially wide-ranging therapeutic impact for treating non-infectious disorders of the human immune system, where it could be applied directly to inflammatory cells. PMID:26384306

  8. Caffeine affects the biological responses of human hematopoietic cells of myeloid lineage via downregulation of the mTOR pathway and xanthine oxidase activity.

    PubMed

    Gibbs, Bernhard F; Gonçalves Silva, Isabel; Prokhorov, Alexandr; Abooali, Maryam; Yasinska, Inna M; Casely-Hayford, Maxwell A; Berger, Steffen M; Fasler-Kan, Elizaveta; Sumbayev, Vadim V

    2015-10-01

    Correction of human myeloid cell function is crucial for the prevention of inflammatory and allergic reactions as well as leukaemia progression. Caffeine, a naturally occurring food component, is known to display anti-inflammatory effects which have previously been ascribed largely to its inhibitory actions on phosphodiesterase. However, more recent studies suggest an additional role in affecting the activity of the mammalian target of rapamycin (mTOR), a master regulator of myeloid cell translational pathways, although detailed molecular events underlying its mode of action have not been elucidated. Here, we report the cellular uptake of caffeine, without metabolisation, by healthy and malignant hematopoietic myeloid cells including monocytes, basophils and primary acute myeloid leukaemia mononuclear blasts. Unmodified caffeine downregulated mTOR signalling, which affected glycolysis and the release of pro-inflammatory/pro-angiogenic cytokines as well as other inflammatory mediators. In monocytes, the effects of caffeine were potentiated by its ability to inhibit xanthine oxidase, an enzyme which plays a central role in human purine catabolism by generating uric acid. In basophils, caffeine also increased intracellular cyclic adenosine monophosphate (cAMP) levels which further enhanced its inhibitory action on mTOR. These results demonstrate an important mode of pharmacological action of caffeine with potentially wide-ranging therapeutic impact for treating non-infectious disorders of the human immune system, where it could be applied directly to inflammatory cells. PMID:26384306

  9. Thrombopoietin cooperates with FLT3-ligand in the generation of plasmacytoid dendritic cell precursors from human hematopoietic progenitors

    PubMed Central

    Chen, Wei; Antonenko, Svetlana; Sederstrom, Joel M.; Liang, Xueqing; Chan, Anissa S. H.; Kanzler, Holger; Blom, Bianca; Blazar, Bruce R.; Liu, Yong-Jun

    2005-01-01

    Type 1 interferon–producing cells (IPCs), also known as plasmacytoid dendritic cell (DC) precursors, represent the key effectors in antiviral innate immunity and triggers for adaptive immune responses. IPCs play important roles in the pathogenesis of systemic lupus erythematosus (SLE) and in modulating immune responses after hematopoietic stem cell transplantation. Understanding IPC development from hematopoietic progenitor cells (HPCs) may provide critical information in controlling viral infection, autoimmune SLE, and graft-versus-host disease. FLT3-ligand (FLT3-L) represents a key IPC differentiation factor from HPCs. Although hematopoietic cytokines such as interleukin-3 (IL-3), IL-7, stem cell factor (SCF), macrophage–colony-stimulating factor (M-CSF), and granulocyte M-CSF (GM-CSF) promote the expansion of CD34+ HPCs in FLT3-L culture, they strongly inhibit HPC differentiation into IPCs. Here we show that thrombopoietin (TPO) cooperates with FLT3-L, inducing CD34+HPCs to undergo a 400-fold expansion in cell numbers and to generate more than 6 × 106 IPCs per 106 CD34+ HPCs within 30 days in culture. IPCs derived from HPCs in FLT3-L/TPO cultures display blood IPC phenotype and have the capacity to produce large amounts of interferon-α (IFN-α) and to differentiate into mature DCs. This culture system, combined with the use of adult peripheral blood CD34+ HPCs purified from G-CSF–mobilized donors, permits the generation of more than 109 IPCs from a single blood donor. PMID:14670916

  10. Consequences of irradiation on bone and marrow phenotypes, and its relation to disruption of hematopoietic precursors

    PubMed Central

    Green, Danielle E.; Rubin, Clinton T.

    2014-01-01

    The rising levels of radiation exposure, specifically for medical treatments and accidental exposures, have added great concern for the long term risks of bone fractures. Both the bone marrow and bone architecture are devastated following radiation exposure. Even sub-lethal doses cause a deficit to the bone marrow microenvironment, including a decline in hematopoietic cells, and this deficit occurs in a dose dependent fashion. Certain cell phenotypes though are more susceptible to radiation damage, with mesenchymal stem cells being more resilient than the hematopoietic stem cells. The decline in total bone marrow hematopoietic cells is accompanied with elevated adipocytes into the marrow cavity, thereby inhibiting hematopoiesis and recovery of the bone marrow microenvironment. Poor bone marrow is also associated with a decline in bone architectural quality. Therefore, the ability to maintain the bone marrow microenvironment would hinder much of the trabecular bone loss caused by radiation exposure, ultimately decreasing some comorbidities in patients exposed to radiation. PMID:24607941

  11. The oncofusion protein FUS–ERG targets key hematopoietic regulators and modulates the all-trans retinoic acid signaling pathway in t(16;21) acute myeloid leukemia

    PubMed Central

    Sotoca, A M; Prange, K H M; Reijnders, B; Mandoli, A; Nguyen, L N; Stunnenberg, H G; Martens, J H A

    2016-01-01

    The ETS transcription factor ERG has been implicated as a major regulator of both normal and aberrant hematopoiesis. In acute myeloid leukemias harboring t(16;21), ERG function is deregulated due to a fusion with FUS/TLS resulting in the expression of a FUS–ERG oncofusion protein. How this oncofusion protein deregulates the normal ERG transcription program is unclear. Here, we show that FUS–ERG acts in the context of a heptad of proteins (ERG, FLI1, GATA2, LYL1, LMO2, RUNX1 and TAL1) central to proper expression of genes involved in maintaining a stem cell hematopoietic phenotype. Moreover, in t(16;21) FUS–ERG co-occupies genomic regions bound by the nuclear receptor heterodimer RXR:RARA inhibiting target gene expression and interfering with hematopoietic differentiation. All-trans retinoic acid treatment of t(16;21) cells as well as FUS–ERG knockdown alleviate the myeloid-differentiation block. Together, the results suggest that FUS–ERG acts as a transcriptional repressor of the retinoic acid signaling pathway. PMID:26148230

  12. The oncofusion protein FUS-ERG targets key hematopoietic regulators and modulates the all-trans retinoic acid signaling pathway in t(16;21) acute myeloid leukemia.

    PubMed

    Sotoca, A M; Prange, K H M; Reijnders, B; Mandoli, A; Nguyen, L N; Stunnenberg, H G; Martens, J H A

    2016-04-14

    The ETS transcription factor ERG has been implicated as a major regulator of both normal and aberrant hematopoiesis. In acute myeloid leukemias harboring t(16;21), ERG function is deregulated due to a fusion with FUS/TLS resulting in the expression of a FUS-ERG oncofusion protein. How this oncofusion protein deregulates the normal ERG transcription program is unclear. Here, we show that FUS-ERG acts in the context of a heptad of proteins (ERG, FLI1, GATA2, LYL1, LMO2, RUNX1 and TAL1) central to proper expression of genes involved in maintaining a stem cell hematopoietic phenotype. Moreover, in t(16;21) FUS-ERG co-occupies genomic regions bound by the nuclear receptor heterodimer RXR:RARA inhibiting target gene expression and interfering with hematopoietic differentiation. All-trans retinoic acid treatment of t(16;21) cells as well as FUS-ERG knockdown alleviate the myeloid-differentiation block. Together, the results suggest that FUS-ERG acts as a transcriptional repressor of the retinoic acid signaling pathway. PMID:26148230

  13. Outcomes of Allogeneic Hematopoietic Cell Transplantation in Children and Young Adults with Chronic Myeloid Leukemia: A CIBMTR Cohort Analysis.

    PubMed

    Chaudhury, Sonali; Sparapani, Rodney; Hu, Zhen-Huan; Nishihori, Taiga; Abdel-Azim, Hisham; Malone, Adriana; Olsson, Richard; Hamadani, Mehdi; Daly, Andrew; Bacher, Ulrike; Wirk, Baldeep M; Kamble, Rammurti T; Gale, Robert P; Wood, William A; Hale, Gregory; Wiernik, Peter H; Hashmi, Shahrukh K; Marks, David; Ustun, Celalettin; Munker, Reinhold; Savani, Bipin N; Alyea, Edwin; Popat, Uday; Sobecks, Ronald; Kalaycio, Matt; Maziarz, Richard; Hijiya, Nobuko; Saber, Wael

    2016-06-01

    Chronic myeloid leukemia (CML) in children and young adults is uncommon. Young patients have long life expectancies and low morbidity with hematopoietic cell transplantation (HCT). Prolonged tyrosine kinase inhibitor (TKI) use may cause significant morbidity. In addition, indication for HCT in patients in the first chronic phase is not established. We hence retrospectively evaluated outcomes in 449 CML patients with early disease receiving myeloablative HCT reported to the CIBMTR. We analyzed various factors affecting outcome, specifically the effect of age and pre-HCT TKI in pediatric patients (age < 18 years, n = 177) and young adults (age 18 to 29 years, n = 272) with the goal of identifying prognostic factors. Post-HCT probability rates of 5-year overall survival (OS) and leukemia-free survival (LFS) were 75% and 59%, respectively. Rates of OS and LFS were 76% and 57% in <18-year and 74% and 60% in 18- to 29-year group, respectively, by univariate analysis (P = .1 and = .6). Five-year rates of OS for HLA matched sibling donor (MSD) and bone marrow (BM) stem cell source were 83% and 80%, respectively. In multivariate analysis there was no effect of age (<18 versus 18 to 29) or pre-HCT TKI therapy on OS, LFS, transplant related mortality, or relapse. Favorable factors for OS were MSD (P < .001) and recent HCT (2003 to 2010; P = .04). LFS was superior with MSD (P < .001), BM as graft source (P = .001), and performance scores > 90 (P = .03) compared with unrelated or mismatched peripheral blood stem cells donors and recipients with lower performance scores. Older age was associated with increased incidence of chronic graft-versus-host disease (P = .0002). In the current era, HCT outcomes are similar in young patients and children with early CML, and best outcomes are achieved with BM grafts and MSD. PMID:26964698

  14. Myeloid Zinc Finger 1 (MZF-1) Regulates Expression of the CCN2/CTGF and CCN3/NOV Genes in the Hematopoietic Compartment.

    PubMed

    Piszczatowski, Richard T; Rafferty, Brian J; Rozado, Andre; Parziale, James V; Lents, Nathan H

    2015-11-01

    Connective Tissue Growth Factor (CCN2/CTGF) and Nephroblastoma Overexpressed (CCN3/NOV) execute key functions within the hematopoietic compartment. Both are abundant in the bone marrow stroma, which is a niche for hematopoiesis and supports marrow function. Roles for 1,25-dihydroxyvitamin D3 (calcitriol) and all-trans retinoic acid in the bone marrow have also been elucidated. Interestingly, some of the annotated roles of these vitamins overlap with established functions of CCN2 and CCN3. Yet, no factor has been identified that unifies these observations. In this study, we report the regulation of the CTGF and NOV genes by Myeloid Zinc Finger-1 (MZF-1), a hematopoietic transcription factor. We show the interaction of MZF-1 with the CTGF and NOV promoters in several cell types. Up-regulation of MZF-1 via calcitriol and vitamin A induces expression of CTGF and NOV, implicating a role for these vitamins in the functions of these two genes. Lastly, knockdown of MZF1 reduces levels of CTGF and NOV. Collectively, our results argue that MZF-1 regulates the CTGF and NOV genes in the hematopoietic compartment, and may be involved in their respective functions in the stroma. PMID:25899830

  15. Loss of IKKβ but Not NF-κB p65 Skews Differentiation towards Myeloid over Erythroid Commitment and Increases Myeloid Progenitor Self-Renewal and Functional Long-Term Hematopoietic Stem Cells.

    PubMed

    Zhang, Jing; Li, Li; Baldwin, Albert S; Friedman, Alan D; Paz-Priel, Ido

    2015-01-01

    NF-κB is an important regulator of both differentiation and function of lineage-committed hematopoietic cells. Targeted deletion of IκB kinase (IKK) β results in altered cytokine signaling and marked neutrophilia. To investigate the role of IKKβ in regulation of hematopoiesis, we employed Mx1-Cre mediated IKKβ conditional knockout mice. As previously reported, deletion of IKKβ in hematopoietic cells results in neutrophilia, and we now also noted decreased monocytes and modest anemia. Granulocyte-macrophage progenitors (GMPs) accumulated markedly in bone marrow of IKKβ deleted mice whereas the proportion and number of megakaryocyte-erythrocyte progenitors (MEP) decreased. Accordingly, we found a significantly reduced frequency of proerythroblasts and basophilic and polychromatic erythroblasts, and IKKβ-deficient bone marrow cells yielded a significantly decreased number of BFU-E compared to wild type. These changes are associated with elevated expression of C/EBPα, Gfi1, and PU.1 and diminished Gata1, Klf1, and SCL/Tal1 in IKKβ deficient Lineage-Sca1+c-Kit+ (LSK) cells. In contrast, no effect on erythropoiesis or expression of lineage-related transcription factors was found in marrow lacking NF-κB p65. Bone marrow from IKKβ knockout mice has elevated numbers of phenotypic long and short term hematopoietic stem cells (HSC). A similar increase was observed when IKKβ was deleted after marrow transplantation into a wild type host, indicating cell autonomous expansion. Myeloid progenitors from IKKβ- but not p65-deleted mice demonstrate increased serial replating in colony-forming assays, indicating increased cell autonomous self-renewal capacity. In addition, in a competitive repopulation assay deletion of IKKβ resulted in a stable advantage of bone marrow derived from IKKβ knockout mice. In summary, loss of IKKβ resulted in significant effects on hematopoiesis not seen upon NF-κB p65 deletion. These include increased myeloid and reduced erythroid

  16. In Vivo Deletion of the Cebpa +37 kb Enhancer Markedly Reduces Cebpa mRNA in Myeloid Progenitors but Not in Non-Hematopoietic Tissues to Impair Granulopoiesis.

    PubMed

    Guo, Hong; Cooper, Stacy; Friedman, Alan D

    2016-01-01

    The murine Cebpa gene contains a +37 kb, evolutionarily conserved 440 bp enhancer that directs high-level expression to myeloid progenitors in transgenic mice. The enhancer is bound and activated by Runx1, Scl, GATA2, C/EBPα, c-Myb, Pu.1, and additional Ets factors in myeloid cells. CRISPR/Cas9-mediated replacement of the wild-type enhancer with a variant mutant in its seven Ets sites leads to 20-fold reduction of Cebpa mRNA in the 32Dcl3 myeloid cell line. To determine the effect of deleting the enhancer in vivo, we now characterize C57BL/6 mice in which loxP sites flank a 688 bp DNA segment containing the enhancer. CMV-Cre mediated germline deletion resulted in diminution of the expected number of viable Enh(f/f);CMV-Cre offspring, with 28-fold reduction in marrow Cebpa mRNA but normal levels in liver, lung, adipose, intestine, muscle, and kidney. Cre-transduction of lineage-negative marrow cells in vitro reduced Cebpa mRNA 12-fold, with impairment of granulocytic maturation, morphologic blast accumulation, and IL-3 dependent myeloid colony replating for >12 generations. Exposure of Enh(f/f);Mx1-Cre mice to pIpC led to 14-fold reduction of Cebpa mRNA in GMP or CMP, 30-fold reduction in LSK, and <2-fold reduction in the LSK/SLAM subset. FACS analysis of marrow from these mice revealed 10-fold reduced neutrophils, 3-fold decreased GMP, and 3-fold increased LSK cells. Progenitor cell cycle progression was mildly impaired. Granulocyte and B lymphoid colony forming units were reduced while monocytic and erythroid colonies were increased, with reduced Pu.1 and Gfi1 and increased Egr1 and Klf4 in GMP. Finally, competitive transplantation indicated preservation of functional long-term hematopoietic stem cells upon enhancer deletion and confirmed marrow-intrinsic impairment of granulopoiesis and B cell generation with LSK and monocyte lineage expansion. These findings demonstrate a critical role for the +37 kb Cebpa enhancer for hematopoietic-specific Cebpa expression

  17. In Vivo Deletion of the Cebpa +37 kb Enhancer Markedly Reduces Cebpa mRNA in Myeloid Progenitors but Not in Non-Hematopoietic Tissues to Impair Granulopoiesis

    PubMed Central

    Guo, Hong; Cooper, Stacy; Friedman, Alan D.

    2016-01-01

    The murine Cebpa gene contains a +37 kb, evolutionarily conserved 440 bp enhancer that directs high-level expression to myeloid progenitors in transgenic mice. The enhancer is bound and activated by Runx1, Scl, GATA2, C/EBPα, c-Myb, Pu.1, and additional Ets factors in myeloid cells. CRISPR/Cas9-mediated replacement of the wild-type enhancer with a variant mutant in its seven Ets sites leads to 20-fold reduction of Cebpa mRNA in the 32Dcl3 myeloid cell line. To determine the effect of deleting the enhancer in vivo, we now characterize C57BL/6 mice in which loxP sites flank a 688 bp DNA segment containing the enhancer. CMV-Cre mediated germline deletion resulted in diminution of the expected number of viable Enh(f/f);CMV-Cre offspring, with 28-fold reduction in marrow Cebpa mRNA but normal levels in liver, lung, adipose, intestine, muscle, and kidney. Cre-transduction of lineage-negative marrow cells in vitro reduced Cebpa mRNA 12-fold, with impairment of granulocytic maturation, morphologic blast accumulation, and IL-3 dependent myeloid colony replating for >12 generations. Exposure of Enh(f/f);Mx1-Cre mice to pIpC led to 14-fold reduction of Cebpa mRNA in GMP or CMP, 30-fold reduction in LSK, and <2-fold reduction in the LSK/SLAM subset. FACS analysis of marrow from these mice revealed 10-fold reduced neutrophils, 3-fold decreased GMP, and 3-fold increased LSK cells. Progenitor cell cycle progression was mildly impaired. Granulocyte and B lymphoid colony forming units were reduced while monocytic and erythroid colonies were increased, with reduced Pu.1 and Gfi1 and increased Egr1 and Klf4 in GMP. Finally, competitive transplantation indicated preservation of functional long-term hematopoietic stem cells upon enhancer deletion and confirmed marrow-intrinsic impairment of granulopoiesis and B cell generation with LSK and monocyte lineage expansion. These findings demonstrate a critical role for the +37 kb Cebpa enhancer for hematopoietic-specific Cebpa expression

  18. Repercussion of Megakaryocyte-Specific Gata1 Loss on Megakaryopoiesis and the Hematopoietic Precursor Compartment

    PubMed Central

    Meinders, Marjolein; Hoogenboezem, Mark; Scheenstra, Maaike R.; De Cuyper, Iris M.; Papadopoulos, Petros; Németh, Tamás; Mócsai, Attila; van den Berg, Timo K.; Kuijpers, Taco W.

    2016-01-01

    During hematopoiesis, transcriptional programs are essential for the commitment and differentiation of progenitors into the different blood lineages. GATA1 is a transcription factor expressed in several hematopoietic lineages and essential for proper erythropoiesis and megakaryopoiesis. Megakaryocyte-specific genes, such as GP1BA, are known to be directly regulated by GATA1. Mutations in GATA1 can lead to dyserythropoietic anemia and pseudo gray-platelet syndrome. Selective loss of Gata1 expression in adult mice results in macrothrombocytopenia with platelet dysfunction, characterized by an excess of immature megakaryocytes. To specifically analyze the impact of Gata1 loss in mature committed megakaryocytes, we generated Gata1-Lox|Pf4-Cre mice (Gata1cKOMK). Consistent with previous findings, Gata1cKOMK mice are macrothrombocytopenic with platelet dysfunction. Supporting this notion we demonstrate that Gata1 regulates directly the transcription of Syk, a tyrosine kinase that functions downstream of Clec2 and GPVI receptors in megakaryocytes and platelets. Furthermore, we show that Gata1cKOMK mice display an additional aberrant megakaryocyte differentiation stage. Interestingly, these mice present a misbalance of the multipotent progenitor compartment and the erythroid lineage, which translates into compensatory stress erythropoiesis and splenomegaly. Despite the severe thrombocytopenia, Gata1cKOMK mice display a mild reduction of TPO plasma levels, and Gata1cKOMK megakaryocytes show a mild increase in Pf4 mRNA levels; such a misbalance might be behind the general hematopoietic defects observed, affecting locally normal TPO and Pf4 levels at hematopoietic stem cell niches. PMID:27152938

  19. Repercussion of Megakaryocyte-Specific Gata1 Loss on Megakaryopoiesis and the Hematopoietic Precursor Compartment.

    PubMed

    Meinders, Marjolein; Hoogenboezem, Mark; Scheenstra, Maaike R; De Cuyper, Iris M; Papadopoulos, Petros; Németh, Tamás; Mócsai, Attila; van den Berg, Timo K; Kuijpers, Taco W; Gutiérrez, Laura

    2016-01-01

    During hematopoiesis, transcriptional programs are essential for the commitment and differentiation of progenitors into the different blood lineages. GATA1 is a transcription factor expressed in several hematopoietic lineages and essential for proper erythropoiesis and megakaryopoiesis. Megakaryocyte-specific genes, such as GP1BA, are known to be directly regulated by GATA1. Mutations in GATA1 can lead to dyserythropoietic anemia and pseudo gray-platelet syndrome. Selective loss of Gata1 expression in adult mice results in macrothrombocytopenia with platelet dysfunction, characterized by an excess of immature megakaryocytes. To specifically analyze the impact of Gata1 loss in mature committed megakaryocytes, we generated Gata1-Lox|Pf4-Cre mice (Gata1cKOMK). Consistent with previous findings, Gata1cKOMK mice are macrothrombocytopenic with platelet dysfunction. Supporting this notion we demonstrate that Gata1 regulates directly the transcription of Syk, a tyrosine kinase that functions downstream of Clec2 and GPVI receptors in megakaryocytes and platelets. Furthermore, we show that Gata1cKOMK mice display an additional aberrant megakaryocyte differentiation stage. Interestingly, these mice present a misbalance of the multipotent progenitor compartment and the erythroid lineage, which translates into compensatory stress erythropoiesis and splenomegaly. Despite the severe thrombocytopenia, Gata1cKOMK mice display a mild reduction of TPO plasma levels, and Gata1cKOMK megakaryocytes show a mild increase in Pf4 mRNA levels; such a misbalance might be behind the general hematopoietic defects observed, affecting locally normal TPO and Pf4 levels at hematopoietic stem cell niches. PMID:27152938

  20. The Cebpa +37-kb enhancer directs transgene expression to myeloid progenitors and to long-term hematopoietic stem cells.

    PubMed

    Guo, Hong; Ma, Ou; Friedman, Alan D

    2014-09-01

    C/EBPα is expressed preferentially in myeloid compared with lymphoid or erythroid cells and directs myeloid lineage specification. C/EBPα is also expressed at lower levels in HSCs and in several nonhematopoietic tissues. The Cebpa gene has a conserved, 450-bp segment at +37 kb that harbors enhancer-specific epigenetic marks and is activate in a myeloid cell line. Herein, we characterize transgenic C57BL/6 mice, in which the Cebpa enhancer and 845-bp promoter regulate a hCD4 reporter. FACS analysis, in vitro colony assays, and in vivo competitive and secondary transplantation revealed that myeloid but not MEPs or lymphoid progenitors and also functional LT-HSCs are found almost exclusively in the Cebpa-hCD4(+) compared with hCD4(-) marrow population. hCD4(+) CMP yielded predominantly myeloid, whereas hCD4(-) CMP generated mainly Meg/E colonies. Providing insight into control of CMP maturation, Cebpa and Pu.1 RNAs were preferentially expressed in hCD4(+) CMP, Scl, Gata2, Gata1, Klf1, Ets1, and Fli1 predominated in hCD4(-) CMP, and Runx1, Myb, HoxA9, and Erg levels were similar in both. Cebpa-hCD4 transgene expression was lacking in multiple nonhematopoietic tissues. In summary, the +37-kb Cebpa enhancer and promoter are sufficient for marrow myeloid progenitor and LT-HSC-specific expression. PMID:24868087

  1. Characteristics of Myeloid Differentiation and Maturation Pathway Derived from Human Hematopoietic Stem Cells Exposed to Different Linear Energy Transfer Radiation Types

    PubMed Central

    Monzen, Satoru; Yoshino, Hironori; Kasai-Eguchi, Kiyomi; Kashiwakura, Ikuo

    2013-01-01

    Exposure of hematopoietic stem/progenitor cells (HSPCs) to ionizing radiation causes a marked suppression of mature functional blood cell production in a linear energy transfer (LET)- and/or dose-dependent manner. However, little information about LET effects on the proliferation and differentiation of HSPCs has been reported. With the aim of characterizing the effects of different types of LET radiations on human myeloid hematopoiesis, in vitro hematopoiesis in Human CD34+ cells exposed to carbon-ion beams or X-rays was compared. Highly purified CD34+ cells exposed to each form of radiation were plated onto semi-solid culture for a myeloid progenitor assay. The surviving fractions of total myeloid progenitors, colony-forming cells (CFC), exposed to carbon-ion beams were significantly lower than of those exposed to X-rays, indicating that CFCs are more sensitive to carbon-ion beams (D0 = 0.65) than to X-rays (D0 = 1.07). Similar sensitivities were observed in granulocyte-macrophage and erythroid progenitors, respectively. However, the sensitivities of mixed-type progenitors to both radiation types were similar. In liquid culture for 14 days, no significant difference in total numbers of mononuclear cells was observed between non-irradiated control culture and cells exposed to 0.5 Gy X-rays, whereas 0.5 Gy carbon-ion beams suppressed cell proliferation to 4.9% of the control, a level similar to that for cells exposed to 1.5 Gy X-rays. Cell surface antigens associated with terminal maturation, such as CD13, CD14, and CD15, on harvest from the culture of X-ray-exposed cells were almost the same as those from the non-irradiated control culture. X-rays increased the CD235a+ erythroid-related fraction, whereas carbon-ion beams increased the CD34+CD38− primitive cell fraction and the CD13+CD14+/−CD15− fraction. These results suggest that carbon-ion beams inflict severe damage on the clonal growth of myeloid HSPCs, although the intensity of cell surface

  2. Age-Related Changes in Population of Stromal Precursor Cells in Hematopoietic and Lymphoid Organs.

    PubMed

    Gorskaya, Yulia F.; Latzinik, Natalia V.; Shuklina, Ekaterina U.; Nesterenko, Vladimir G.

    2000-07-01

    It is shown that the content of precursor cells of stromal tissue (CFC-F) in the hemopoietic and lymphoid organs of SAMP (rapidly-ageing mice) and SAMR mice (mice with a normal ageing rate) decreases as the animals grow older. However the decrease in the content of CFC-F in SAMP mice begins substantially earlier - in the age group of 9-11 months, while in the SAMR mice - only in the age group of 16-19 months. It was found that the age reduction of the number to an equal degree relates to the whole population of CFC-F, in particular both the fraction of weakly-linked CFC-F, which is isolated by means of mechanical disaggregation of the tissue, and the fraction which may only be isolated using trypsin. It is shown that the concentration of inducible osteogenic precursor cells (IOPC) in the spleen of guinea pigs does not change with age, but their content in that organ in old animals (2-3 years old) drops by two times. It was found that in elderly animals the mass of the ectopic osseous tissue, formed by the implantation of an osteoinductor (autologous epithelium of the urinary bladder) in a system open for entrance of cells, decreases by two times. After curettage of the medullary cavity of guinea pig tibia (i.e. under conditions of an increased demand for osteogenic cells) the mass of induced ectopic osseous tissue decreases by 4 times, which indicates to the possible functional relationship between the pool of determined and inducible osteogenic precursor cells. On the whole, the obtained data show that during ageing there is a reduction in the number of stromal precursor cells (CFC-F and IOPC), which form a specific microenvironment for hemopoietic and lymphoid organs, which is important to understand the role of these cells in the development of age pathologies, in particular senile osteoporosis. PMID:12687170

  3. Evaluation of hematopoietic cells and myeloid/erythroid ratio in the bone marrow of the pheasant (Phasianus colchicus).

    PubMed

    Tadjalli, Mina; Nazifi, Saeed; Haghjoo, Rahil

    2013-01-01

    In order to study the normal hematopoiesis, cellular components and myeloid/erythroid (M/E) ratio in the bone marrow of the pheasant (Phasianus colchicus), bone marrow samples were collected from the proximal tibiotarsus bone of 16 clinically healthy adult pheasant. The bone marrow smears were stained using the Giemsa stain. The results indicated that the development and formation of blood cells in the bone marrow of pheasant were similar to other birds, whereas the morphology of the cells was similar to chickens, ducks, quail, and black-head gull. The mean M/E ratio was 1.24, the mean erythroid percentage was 42.24, the mean myeloid percentage was 52.62, and the mean percentage of all other cells percentage was 5.38. There was no significant difference in any of the cellular composition between male and female. PMID:25653783

  4. High rate of hematological responses to sorafenib in FLT3-ITD acute myeloid leukemia relapsed after allogeneic hematopoietic stem cell transplantation.

    PubMed

    De Freitas, Tiago; Marktel, Sarah; Piemontese, Simona; Carrabba, Matteo G; Tresoldi, Cristina; Messina, Carlo; Lupo Stanghellini, Maria Teresa; Assanelli, Andrea; Corti, Consuelo; Bernardi, Massimo; Peccatori, Jacopo; Vago, Luca; Ciceri, Fabio

    2016-06-01

    Relapse represents the most significant cause of failure of allogeneic hematopoietic stem cell transplantation (HSCT) for FLT3-ITD-positive acute myeloid leukemia (AML), and available therapies are largely unsatisfactory. In this study, we retrospectively collected data on the off-label use of the tyrosine kinase inhibitor sorafenib, either alone or in association with hypomethylating agents and adoptive immunotherapy, in 13 patients with post-transplantation FLT3-ITD-positive AML relapses. Hematological response was documented in 12 of 13 patients (92%), and five of 13 (38%) achieved complete bone marrow remission. Treatment was overall manageable in the outpatient setting, although all patients experienced significant adverse events, especially severe cytopenias (requiring a donor stem cell boost in five patients) and typical hand-foot syndrome. None of the patients developed graft-vs.-host disease following sorafenib alone, whereas this was frequently observed when this was given in association with donor T-cell infusions. Six patients are alive and in remission at the last follow-up, and four could be bridged to a second allogeneic HSCT, configuring a 65 ± 14% overall survival at 100 d from relapse. Taken together, our data suggest that sorafenib might represent a valid treatment option for patients with FLT3-ITD-positive post-transplantation relapses, manageable also in combination with other therapeutic strategies. PMID:26260140

  5. Splenic irradiation before hematopoietic stem cell transplantation for chronic myeloid leukemia: long-term follow-up of a prospective randomized study.

    PubMed

    Gratwohl, Alois; Iacobelli, Simona; Bootsman, Natalia; van Biezen, Anja; Baldomero, Helen; Arcese, William; Arnold, Renate; Bron, Dominique; Cordonnier, Catherine; Ernst, Peter; Ferrant, Augustin; Frassoni, Francesco; Gahrton, Gösta; Richard, Carlos; Kolb, Hans Jochem; Link, Hartmut; Niederwieser, Dietger; Ruutu, Tapani; Schattenberg, Anton; Schmitz, Norbert; Torres-Gomez, Antonio; Zwaan, Ferry; Apperley, Jane; Olavarria, Eduardo; Kröger, Nicolaus

    2016-05-01

    In the context of discussions on the reproducibility of clinical studies, we reanalyzed a prospective randomized study on the role of splenic irradiation as adjunct to the conditioning for hematopoietic stem cell transplantation (HSCT) for chronic myeloid leukemia (CML). Between 1986 and 1989, a total of 229 patients with CML were randomized; of these, 225 (98 %; 112 with, 113 without splenic irradiation) could be identified in the database and their survival updated. Results confirmed the early findings with no significant differences in all measured endpoints (overall survival at 25 years: 42.7 %, 32.0-52.4 % vs 52.9 %, 43.2-62.6 %; p = 0.355, log rank test). Additional splenic irradiation failed to reduce relapse incidence. It did not increase non-relapse mortality nor the risk of late secondary malignancies. Comforting are the long-term results from this predefined consecutive cohort of patients: more than 60 % were alive at plus 25 years when they were transplanted with a low European Society for Blood and Marrow Transplantation (EBMT) risk sore. This needs to be considered today when treatment options are discussed for patients who failed initial tyrosine kinase inhibitor therapy and have an available low risk HLA-identical donor. PMID:26994010

  6. HIGH PROBABILITY OF LONG-TERM SURVIVAL IN 2-YEAR SURVIVORS OF AUTOLOGOUS HEMATOPOIETIC CELL TRANSPLANTATION FOR ACUTE MYELOID LEUKEMIA IN FIRST OR SECOND COMPLETE REMISSION

    PubMed Central

    Majhail, Navneet S.; Bajorunaite, Ruta; Lazarus, Hillard M.; Wang, Zhiwei; Klein, John P.; Zhang, Mei-Jie; Rizzo, J. Douglas

    2010-01-01

    We describe long-term outcomes of autologous hematopoietic-cell transplantation (HCT) for 315 acute myeloid leukemia (AML) patients in first or second complete remission (CR). All patients were in continuous CR for ≥2-years post-HCT. Patients were predominantly transplanted in CR1 (78%) and had good or intermediate cytogenetic risk disease (74%). Median followup of survivors was 106 (range, 24-192) months. Overall survival at 10-years post-HCT was 94% (95% confidence intervals, 89-97%) and 80% (67-91%) for patients receiving HCT in CR1 and CR2, respectively. The cumulative incidence of relapse at 10-years post-HCT was 6% (3-10%) and 10% (3-20%) and that of non-relapse mortality was 5% (2-9%) and 11% (4-21%), respectively. On multivariate analysis, HCT in CR2 (vs. CR1), older age at transplantation and poor cytogenetic risk disease were independent predictors of late mortality and adverse disease-free survival. The use of growth factors to promote engraftment following HCT was the only risk factor for relapse. Relative-mortality of these 2-year survivors was comparable to that of age-, race- and gender-matched normal population. Patients who receive an autologous HCT for AML in CR1 or CR2 and remain in remission for ≥2-years have very favorable long-term survival. Their mortality rates are similar to that of the general population. PMID:20479710

  7. Protective effect of cytomegalovirus reactivation on relapse after allogeneic hematopoietic cell transplantation in acute myeloid leukemia patients is influenced by conditioning regimen.

    PubMed

    Manjappa, Shivaprasad; Bhamidipati, Pavan Kumar; Stokerl-Goldstein, Keith E; DiPersio, John F; Uy, Geoffrey L; Westervelt, Peter; Liu, Jingxia; Schroeder, Mark A; Vij, Ravi; Abboud, Camille N; Fehniger, Todd A; Cashen, Amanda F; Pusic, Iskra; Jacoby, Meagan; Meera, Srinidhi J; Romee, Rizwan

    2014-01-01

    Cytomegalovirus (CMV) reactivation after allogeneic hematopoietic cell transplant (allo-HCT) has been associated with a reduced risk of relapse in patients with acute myeloid leukemia (AML). However, the influence of the conditioning regimen on this protective effect of CMV reactivation after allo-HCT is relatively unexplored. To address this, we evaluated the risk of relapse in 264 AML patients who received T cell-replete, 6/6 HLA matched sibling or 10/10 HLA matched unrelated donor transplantation at a single institution between 2006 and 2011. Of these 264 patients, 206 received myeloablative (MA) and 58 received reduced-intensity conditioning (RIC) regimens. CMV reactivation was observed in 88 patients with MA conditioning and 37 patients with RIC. At a median follow-up of 299 days, CMV reactivation was associated with significantly lower risk of relapse in patients who received MA conditioning both in univariate (P = .01) and multivariate analyses (hazard ratio, .5246; P = .006); however, CMV reactivation did not significantly affect the risk of relapse in our RIC cohort. These results confirm the protective effect of CMV reactivation on relapse in AML patients after allo-HCT reported by previous studies but suggest this protective effect of CMV reactivation on relapse is influenced by the conditioning regimen used with the transplant. PMID:24120526

  8. Comparison of Outcomes after Peripheral Blood Haploidentical versus Matched Unrelated Donor Allogeneic Hematopoietic Cell Transplantation in Patients with Acute Myeloid Leukemia: A Retrospective Single-Center Review.

    PubMed

    Rashidi, Armin; DiPersio, John F; Westervelt, Peter; Vij, Ravi; Schroeder, Mark A; Cashen, Amanda F; Fehniger, Todd A; Romee, Rizwan

    2016-09-01

    Recent studies comparing allogeneic hematopoietic cell transplantation (HCT) using HLA-matched unrelated donors (MUD) versus HLA-haploidentical donors in patients with acute myeloid leukemia (AML) have suggested equivalent outcomes. The graft source used in most studies of haploidentical transplants has been bone marrow. Similar comparisons between MUD and haplo-HCT using peripheral blood as a graft source have not been adequately performed. We reviewed the records of all 52 AML patients who underwent haplo-HCT (using peripheral blood and post-transplantation high-dose cyclophosphamide) between January 2010 and August 2015 at our institution and compared their outcomes with 88 patients who had a MUD transplant in the same time frame and were frequency matched (preanalysis) to the haploidentical group for conditioning intensity. Multivariate analysis found no difference in outcomes between the 2 groups with the exception of slower count recovery after haploidentical allografts (HR, .48; 95% CI, .32 to .74 for platelets, and HR, .47; 95% CI, .32 to .71 for neutrophils; P < .001 for both comparisons). Our retrospective analysis, although limited by the small sample size, suggests largely similar outcomes with peripheral blood haploidentical versus MUD transplants for AML. PMID:27223108

  9. Spontaneous remission of acute myeloid leukemia relapse after hematopoietic cell transplantation in a high-risk patient with 11q23/MLL abnormality.

    PubMed

    Hudecek, Michael; Bartsch, Kristina; Jäkel, Nadja; Heyn, Simone; Pfannes, Roald; Al-Ali, Haifa Kathrin; Cross, Michael; Pönisch, Wolfram; Gerecke, Ulrich; Edelmann, Jeanett; Ittel, Thomas; Niederwieser, Dietger

    2008-01-01

    A 35-year-old female patient was diagnosed with acute myeloid leukemia with multiple genetic aberrations [48 XX, del(3)(q21), +6, t(11;15)(q23;q15), +21] including an 11q23/MLL abnormality. The patient achieved a complete remission after one induction chemotherapy cycle. After three courses of consolidation, a matched unrelated hematopoietic cell transplantation (HCT) was performed. Following an upper respiratory tract infection 7 years after transplant, her blood counts declined to leukocytes of 1 x 10(9)/l, platelets of 51 x 10(9)/l and hemoglobin of 7.5 g/dl. A bone marrow aspirate revealed 55% leukemic blasts carrying the unfavorable genetic aberrations seen at initial diagnosis (11q23/MLL). In the absence of any disease-specific treatment, the leukemic blasts cleared from the bone marrow within 6 days after diagnosis of relapse and peripheral blood counts returned to normal. Molecular analysis of the 11q23/MLL rearrangement was used to evaluate minimal residual disease, which became undetectable in repetitive FISH analyses. This is the first report of spontaneous remission in a patient with initially a multiaberrant leukemic cell clone and a proven 11q23/MLL abnormality at relapse after HCT. PMID:18367831

  10. Allogeneic Hematopoietic Cell Transplant for Acute Myeloid Leukemia: No Impact of Pre-transplant Extramedullary Disease on Outcome

    PubMed Central

    Goyal, Sagun D.; Zhang, Mei-Jie; Wang, Hai-Lin; Akpek, Görgün; Copelan, Edward A.; Freytes, César; Gale, Robert Peter; Hamadani, Mehdi; Inamoto, Yoshihiro; Kamble, Rammurti T.; Lazarus, Hillard M.; Marks, David I.; Nishihori, Taiga; Olsson, Richard F.; Reshef, Ran; Ritchie, David S.; Saber, Wael; Savani, Bipin N.; Seber, Adriana; Shea, Thomas C.; Tallman, Martin S.; Wirk, Baldeep; Bunjes, Donald W.; Devine, Steven M.; de Lima, Marcos; Weisdorf, Daniel J.; Uy, Geoffrey L.

    2015-01-01

    The impact of extramedullary disease (EMD) in AML on the outcomes of allogeneic hematopoietic cell transplantation (alloHCT) is unknown. Using data from the Center for International Blood and Marrow Transplant Research (CIBMTR) we compared the outcomes of patients who had EMD of AML at any time prior to transplant to a cohort of AML patients without EMD. We reviewed data AML from 9,797 patients including 814 with EMD from 310 reporting centers and 44 different countries who underwent alloHCT between and 1995–2010. The primary outcome was overall survival (OS) after alloHCT. Secondary outcomes included leukemia-free survival (LFS), relapse rate, and treatment-related mortality (TRM). In a multivariate analysis, the presence of EMD did not affect either OS (HR 1.00, 95% CI 0.91–1.09), LFS (0.98, 0.89–1.09), TRM (RR 0.92, 95% CI 0.80–1.16, p=0.23) or relapse (RR =1.03, 95% CI, 0.92–1.16; p=0.62). Furthermore, the outcome of patients with EMD was not influenced by the location, timing of EMD, or intensity of conditioning regimen. The presence of EMD in AML does not affect transplant outcomes and should not be viewed as an independent adverse prognostic feature. PMID:25915806

  11. Impact of Cranial Irradiation Added to Intrathecal Conditioning in Hematopoietic Cell Transplantation in Adult Acute Myeloid Leukemia With Central Nervous System Involvement

    SciTech Connect

    Mayadev, Jyoti S.; Douglas, James G.; Storer, Barry E.; Appelbaum, Frederick R.; Storb, Rainer

    2011-05-01

    Purpose: Neither the prognostic importance nor the appropriate management of central nervous system (CNS) involvement is known for patients with acute myeloid leukemia (AML) undergoing hematopoietic cell transplantation (HCT). We examined the impact of a CNS irradiation boost to standard intrathecal chemotherapy (ITC). Methods and Materials: From 1995 to 2005, a total of 648 adult AML patients received a myeloablative HCT: 577 patients were CNS negative (CNS-), and 71 were CNS positive (CNS+). Of the 71 CNS+ patients, 52 received intrathecal chemotherapy alone (CNS+ITC), and 19 received ITC plus an irradiation boost (CNS+RT). Results: The CNS-, CNS+ITC, and CNS+RT patients had 1- and 5-year relapse-free survivals (RFS) of 43% and 35%, 15% and 6%, and 37% and 32%, respectively. CNS+ITC patients had a statistically significant worse RFS compared with CNS- patients (hazard ratio [HR], 2.65; 95% confidence interval [CI], 2.0-3.6; p < 0.0001). CNS+RT patients had improved relapse free survival over that of CNS+ITC patients (HR, 0.45; 95% CI, 0.2-0.8; p = 0.01). The 1- and 5-year overall survivals (OS) of patients with CNS-, CNS+ITC, and CNS+RT, were 50% and 38%, 21% and 6%, and 53% and 42%, respectively. The survival of CNS+RT were significantly better than CNS+ITC patients (p = 0.004). After adjusting for known risk factors, CNS+RT patients had a trend toward lower relapse rates and reduced nonrelapse mortality. Conclusions: CNS+ AML is associated with a poor prognosis. The role of a cranial irradiation boost to intrathecal chemotherapy appears to mitigate the risk of CNS disease, and needs to be further investigated to define optimal treatment strategies.

  12. Relapse and Late Mortality in 5-Year Survivors of Myeloablative Allogeneic Hematopoietic Cell Transplantation for Chronic Myeloid Leukemia in First Chronic Phase

    PubMed Central

    Goldman, John M.; Majhail, Navneet S.; Klein, John P.; Wang, Zhiwei; Sobocinski, Kathleen A.; Arora, Mukta; Horowitz, Mary M.; Rizzo, J. Douglas

    2010-01-01

    Purpose Allogeneic hematopoietic cell transplantation (HCT) is curative therapy for chronic myeloid leukemia (CML), but its long-term outcomes are not well described. We studied the long-term outcomes of CML patients in first chronic phase who receive an allogeneic HCT. Patients and Methods Our study included 2,444 patients who received myeloablative HCT for CML in first chronic phase between 1978 and 1998 and survived in continuous complete remission for at least 5 years (median follow-up, 11 years; range, 5 to 25 years). Donor sources were human leukocyte antigen–matched siblings in 1,692 patients, unrelated donors in 639 patients, and other related donors in 113 patients. Results Overall survival rates at 15 years were 88% (95% CI, 86% to 90%) for sibling HCT and 87% (95% CI, 83% to 90%) for unrelated donor HCT. Corresponding cumulative incidences of relapse were 8% (95% CI, 7% to 10%) and 2% (95% CI, 1% to 4%), respectively. The latest relapse was reported 18 years post-HCT. In multivariable analyses, history of chronic graft-versus-host disease increased risks of late overall mortality and nonrelapse mortality but reduced risks of relapse. In comparison with age-, race-, and sex-adjusted normal populations, the mortality of HCT recipients was significantly higher until 14 years post-HCT; thereafter, mortality rates were similar to those of the general population (relative mortality ratio at 15 years, 2.3; 95% CI, 0 to 4.9). Conclusion Recipients of allogeneic HCT for CML in first chronic phase who remain in remission for at least 5 years have favorable subsequent long-term survival, and their mortality rates eventually approach those of the general population. PMID:20212247

  13. Impact of age on outcomes of allogeneic hematopoietic stem cell transplantation with reduced intensity conditioning in elderly patients with acute myeloid leukemia.

    PubMed

    Aoki, Jun; Kanamori, Heiwa; Tanaka, Masatsugu; Yamasaki, Satoshi; Fukuda, Takahiro; Ogawa, Hiroyasu; Iwato, Koji; Ohashi, Kazuteru; Okumura, Hirokazu; Onizuka, Makoto; Maesako, Yoshitomo; Teshima, Takanori; Kobayashi, Naoki; Morishima, Yasuo; Hirokawa, Makoto; Atsuta, Yoshiko; Yano, Shingo; Takami, Akiyoshi

    2016-03-01

    Previous studies have repeatedly reported that increasing age is a significant risk factor for worse outcomes after allogeneic hematopoietic stem cell transplantation (allo-HSCT) among patients with acute myeloid leukemia (AML). However, more recent studies reported conflicting results regarding the association between age and outcomes in elderly patients. Therefore, we conducted a large-scale, nationwide retrospective study to examine the impact of age on outcomes of allo-HSCT with reduced intensity conditioning (RIC) for AML patients who were older than 50 years. Of the 757 patients, 89 patients (11.8%) were 50-54, 249 patients (32.9%) were 55-59, 301 patients (39.8%) were 60-64 and 118 patients (15.6%) were ≥65 years old. The 3-year overall survival (OS) (47.8, 45.2, 37.9, and 36.6% for patients aged 50-54, 55-59, 60-64, and ≥65 years, respectively, P = 0.24) and nonrelapse mortality (NRM) (24.0, 22.8, 29.2, and 27.6% for patients aged 50-54, 55-59, 60-64, and ≥65 years, respectively, P = 0.49) were not significantly different among the four age groups. Multivariate analysis revealed that increased age had no significant effect on OS or NRM after adjusting for covariates. These results suggested that advanced patient age is not a contraindication for RIC allo-HSCT in elderly AML patients. PMID:26663096

  14. Monosomal karyotype as an adverse prognostic factor in patients with acute myeloid leukemia treated with allogeneic hematopoietic stem-cell transplantation in first complete remission: a retrospective survey on behalf of the ALWP of the EBMT

    PubMed Central

    Brands-Nijenhuis, Angelique V.M.; Labopin, Myriam; Schouten, Harry C.; Volin, Liisa; Socié, Gérard; Cornelissen, Jan J.; Huynh, Anne; Ljungman, Per; Malard, Florent; Esteve, Jordi; Nagler, Arnon; Mohty, Mohamad

    2016-01-01

    Despite the overall benefit from allogeneic hematopoietic stem cell transplantation observed in patients with poor cytogenetic risk acute myeloid leukemia in first complete remission, the precise effect of this procedure for different poor-risk subtypes has not been fully analyzed. This retrospective analysis was performed to investigate whether allogeneic hematopoietic stem cell transplantation performed in first complete remission in patients with monosomal karyotype can overcome the adverse prognosis associated with these patients. Of the 4635 patients included in the study, 189 (4%) harbored a monosomal karyotype. The presence of a monosomal karyotype was associated with a worse outcome, with an inferior leukemia-free survival and overall survival (5-year leukemia-free survival and overall survival: 24±3% and 26±3% vs. 53±1% and 57±1% in monosomal-karyotype and non-monosomal-karyotype, respectively; P<0.0001) and higher relapse risk after transplantation (cumulative incidence of relapse at 5 years: 56±4% in monosomal-karyotype vs. 28±1% in non-monosomal-karyotype; P<0.0001). The adverse negative impact of monosomal karyotype cytogenetics was confirmed in the entire cohort in a multivariate analysis [Hazard Ratio (HR): 1.88, 95% Confidence Interval (CI):1.29–2.73, P=0.001 for relapse incidence; HR:1.71, 95%CI:1.27–2.32, P<0.0001 for leukemia-free survival; HR:1.81, 95%CI:1.32–2.48, P=0.0002 for overall survival], and was independent of the presence of other poor-risk cytogenetic subtypes. In summary, monosomal karyotype arises as a strong negative prognostic feature in acute myeloid leukemia also in patients who undergo allogeneic hematopoietic stem cell transplantation in first complete remission, stressing the need to develop additional pre- and post-transplantation strategies aimed at improving overall results. Nonetheless, allogeneic hematopoietic stem cell transplantation in early phase is currently the best therapy for this very poor-risk acute

  15. Efficacy of Allogeneic Hematopoietic Stem Cell Transplantation in Intermediate-Risk Acute Myeloid Leukemia Adult Patients in First Complete Remission: A Meta-Analysis of Prospective Studies

    PubMed Central

    Zhu, Honghu; Dou, Liping; Liu, Daihong; Fu, Lin; Ma, Cong; Ma, Xuebin; Yao, Yushi; Zhou, Lei; Wang, Qian; Wang, Lijun; Zhao, Yu; Jing, Yu; Wang, Lili; Li, Yonghui; Yu, Li

    2015-01-01

    Hematopoietic stem cell transplantation (HSCT) and consolidation chemotherapy have been used to treat intermediate-risk acute myeloid leukemia (AML) patients in first complete remission (CR1). However, it is still unclear which treatments are most effective for these patients. The aim of our study was to analyze the relapse-free survival (RFS) and overall survival (OS) benefit of allogeneic HSCT (alloHSCT) for intermediate-risk AML patients in CR1. A meta-analysis of prospective trials comparing alloHSCT to non-alloHSCT (autologous HSCT [autoHSCT] and/or chemotherapy) was undertaken. We systematically searched PubMed, Embase, and the Cochrane Library though October 2014, using keywords and relative MeSH or Emtree terms, ‘allogeneic’; ‘acut*’ and ‘leukem*/aml/leukaem*/leucem*/leucaem*’; and ‘nonlympho*’ or ‘myelo*’. A total of 7053 articles were accessed. The primary outcomes were RFS and OS, while the secondary outcomes were treatment-related mortality (TRM) and relapse rate (RR). Hazard ratios (HR) and 95% confidence intervals (CI) were calculated for each outcome. The primary outcomes were RFS and OS, while the secondary outcomes were TRM and RR. We included 9 prospective controlled studies including 1950 adult patients. Patients with intermediate-risk AML in CR1 who received either alloHSCT or non-alloHSCT were considered eligible. AlloHSCT was found to be associated with significantly better RFS, OS, and RR than non-alloHSCT (HR, 0.684 [95% CI: 0.48, 0.95]; HR, 0.76 [95% CI: 0.61, 0.95]; and HR, 0.58 [95% CI: 0.45, 0.75], respectively). TRM was significantly higher following alloHSCT than non-alloHSCT (HR, 3.09 [95% CI: 1.38, 6.92]). However, subgroup analysis showed no OS benefit for alloHSCT over autoHSCT (HR, 0.99 [95% CI: 0.70, 1.39]). In conclusion, alloHSCT is associated with more favorable RFS, OS, and RR benefits (but not TRM outcomes) than non-alloHSCT generally, but does not have an OS advantage over autoHSCT specifically, in

  16. The Superiority of Allogeneic Hematopoietic Stem Cell Transplantation Over Chemotherapy Alone in the Treatment of Acute Myeloid Leukemia Patients with Mixed Lineage Leukemia (MLL) Rearrangements

    PubMed Central

    Yang, Hua; Huang, Sai; Zhu, Cheng-Ying; Gao, Li; Zhu, Hai-Yan; Lv, Na; Jing, Yu; Yu, Li

    2016-01-01

    Background Acute myeloid leukemia (AML) patients with mixed lineage leukemia (MLL) gene rearrangements always had a very poor prognosis. In this study, we report the incidence of MLL rearrangements in AML patients using gene analysis, as well as the clinical significance and prognostic features of these rearrangements. Material/Methods This retrospective study took place from April 2008 to November 2011 in the People’s Liberation Army General Hospital. A total 433 AML patients were screened by multiple nested reverse transcription polymerase chain reaction (RT-PCR) to determine the incidence of the 11 MLL gene rearrangements. There were 68 cases of MLL gene rearrangements, for a positive rate of 15.7%. A total of 24 patients underwent allogeneic hematopoietic stem cell transplantation (Allo-HSCT), and 34 patients received at least 4 cycles of chemotherapy. Ten patients were lost to follow-up. Results The median follow-up was 29 months. The complete remission (CR) rate was 85.4%. The overall survival (OS) was 57.4±5.9 months for the Allo-HSCT group and 21.0±2.1 months for the chemotherapy group. The Allo-HSCT group had superior survival compared with the chemotherapy group (5-year OS: 59±17% vs. 13±8%, P<0.01; 5-year disease-free survival [DFS]: 65±10% vs. 40±16%, P>0.05). Multivariate analysis showed that transplantation, platelets >50×109/L at onset, and CR are associated with a better OS in MLL rearranged AML patients. Patients with thrombocytopenia and extramedullary involvement were prone to relapse. Conclusions Our results suggest that Allo-HSCT is superior to chemotherapy alone for treating MLL rearranged AML patients. Patients treated with Allo-HSCT have a better prognosis and a longer survival. CR is an independent prognostic factor for OS, and extramedullary involvement is an independent prognostic factor for DFS. MLL rearranged AML patients with thrombocytopenia at onset <50×109 had very bad OS and DFS. PMID:27373985

  17. Allogeneic hematopoietic stem cell transplantation could improve survival of cytogenetically normal adult acute myeloid leukemia patients with DNMT3A mutations.

    PubMed

    Xu, Yang; Sun, Yanjun; Shen, Hongjie; Ding, Lin; Yang, Zhen; Qiu, Huiying; Sun, Aining; Chen, Suning; Wu, Depei

    2015-11-01

    DNMT3A mutations are frequent in cytogenetically normal acute myeloid leukemia (cn-AML) patients and associated with poor survival. The role of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in DNMT3A(mut) cn-AML patients remains unclear. In this study, we retrospectively analyzed the prognostic impact of DNMT3A mutations and explored the role of allo-HSCT in 308 cn-AML patients who received consolidation of intensive chemotherapy or allo-HSCT in our center from March 2005 to May 2014. In the whole cohort, 63 patients (20.5%) were identified with DNMT3A exon 23 mutations and R882H was the most frequent variant. DNMT3A(mut) patients had shorter overall survival (3-year OS: 31.9% vs. 52.0%, P = 0.009) and disease-free survival (3-year DFS: 21.8% vs. 40.1%, P = 0.004) compared with DNMT3A(wt) patients. Based on FLT3/NPM1/CEBPA mutations, 308 cn-AML patients were divided into favorable/intermediate group (n = 262) and unfavorable group (n = 46). There were no significant differences in 3-year OS and 3-year DFS between DNMT3A(mut) and DNMT3A(wt) patients in both favorable/intermediate and unfavorable groups. Additionally, in multivariate analysis, DNMT3A mutation remained an independent adverse prognostic factor for the survival. In the DNMT3A(mut) cohort, 23 complete remission (CR) patients received allo-HSCT consolidation and 32 CR patients received chemotherapy consolidation, dramatic differences were observed in 3-year OS (51.7% vs. 28.9%, P = 0.048) and 3-year DFS (41.6% vs. 14.9%, P = 0.024) between allo-HSCT group and chemotherapy group. Collectively, DNMT3A mutation is a poor prognostic factor for cn-AML patients and allo-HSCT could improve survival of cn-AML patients with DNMT3A mutations. PMID:26223865

  18. The Superiority of Allogeneic Hematopoietic Stem Cell Transplantation Over Chemotherapy Alone in the Treatment of Acute Myeloid Leukemia Patients with Mixed Lineage Leukemia (MLL) Rearrangements.

    PubMed

    Yang, Hua; Huang, Sai; Zhu, Cheng-Ying; Gao, Li; Zhu, Hai-Yan; Lv, Na; Jing, Yu; Yu, Li

    2016-01-01

    BACKGROUND Acute myeloid leukemia (AML) patients with mixed lineage leukemia (MLL) gene rearrangements always had a very poor prognosis. In this study, we report the incidence of MLL rearrangements in AML patients using gene analysis, as well as the clinical significance and prognostic features of these rearrangements. MATERIAL AND METHODS This retrospective study took place from April 2008 to November 2011 in the People's Liberation Army General Hospital. A total 433 AML patients were screened by multiple nested reverse transcription polymerase chain reaction (RT-PCR) to determine the incidence of the 11 MLL gene rearrangements. There were 68 cases of MLL gene rearrangements, for a positive rate of 15.7%. A total of 24 patients underwent allogeneic hematopoietic stem cell transplantation (Allo-HSCT), and 34 patients received at least 4 cycles of chemotherapy. Ten patients were lost to follow-up. RESULTS The median follow-up was 29 months. The complete remission (CR) rate was 85.4%. The overall survival (OS) was 57.4±5.9 months for the Allo-HSCT group and 21.0±2.1 months for the chemotherapy group. The Allo-HSCT group had superior survival compared with the chemotherapy group (5-year OS: 59±17% vs. 13±8%, P<0.01; 5-year disease-free survival [DFS]: 65±10% vs. 40±16%, P>0.05). Multivariate analysis showed that transplantation, platelets >50×10^9/L at onset, and CR are associated with a better OS in MLL rearranged AML patients. Patients with thrombocytopenia and extramedullary involvement were prone to relapse. CONCLUSIONS Our results suggest that Allo-HSCT is superior to chemotherapy alone for treating MLL rearranged AML patients. Patients treated with Allo-HSCT have a better prognosis and a longer survival. CR is an independent prognostic factor for OS, and extramedullary involvement is an independent prognostic factor for DFS. MLL rearranged AML patients with thrombocytopenia at onset <50×10^9 had very bad OS and DFS. PMID:27373985

  19. Differential sensitivity of T lymphocytes and hematopoietic precursor cells to photochemotherapy with 8-methoxypsoralen and ultraviolet A light.

    PubMed

    Mabed, Mohamed; Coffe, Christian; Racadot, Evelyne; Angonin, Regis; Pavey, Jean-Jaques; Tiberghien, Pierre; Herve, Patrick

    2006-01-01

    The combination of 8-methoxypsoralen (8-MOP) and long wave ultraviolet radiation (UV-A) has immunomodulatory effects and might abolish both graft-vs-host and host-vs-graft reactions after allogeneic hematopoietic stem cell transplantation. In the present study, we have confirmed the sensitivity of T lymphocytes to 8-MOP treatment plus UV-A exposure as evidenced by the abrogation of the alloreactivity in mixed lymphocyte cultures as well as the inhibition of the response to phytohemagglutinin A. However, the clonogenic capacity of the bone marrow hematopoietic progenitors was inhibited with UV-A doses lower than the doses needed to inhibit T-lymphocytes alloreactivity. Moreover, long-term bone marrow cultures showed that 8-MOP plus UV-A treatment had detrimental effects on the more immature bone marrow stem cells. These data were confirmed when murine bone marrow graft was treated with 8-MOP, exposed to UV-A, then transplanted into semiallogeneic recipient mice. The treated cells could not maintain their clonogenic capacity in vivo resulting in death of all animals. Taken together, these data show that ex vivo 8-MOP plus UV-A treatment of the marrow graft cannot be used to prevent post-bone marrow transplantation alloreactivity. PMID:16208471

  20. The HIF-1 transcription complex is essential for translational control of myeloid hematopoietic cell function by maintaining mTOR phosphorylation.

    PubMed

    Yasinska, Inna M; Gibbs, Bernhard F; Lall, Gurprit S; Sumbayev, Vadim V

    2014-02-01

    Mammalian myeloid cells are crucial effectors of host innate immune defense. Normal and pathological responses of these cells require adaptation to signaling stress through the hypoxia-inducible factor 1 (HIF-1) transcription complex. Adapted cells activate the mammalian target of rapamycin (mTOR), via S2448 phosphorylation, which induces de novo translation of vital signaling proteins. However, the molecular mechanisms underlying this signaling dogma remain unclear. Here, we demonstrate for the first time that inactivation of HIF-1, by silencing its inducible alpha subunit, significantly decreases mTOR S2448 phosphorylation caused by ligand-dependent activation of human myeloid leukemia cells. This shows that HIF-1 is essential for the activation of mTOR and serves at a crucial juncture of myeloid cell function in both in vitro and in vivo systems. PMID:23872956

  1. Involvement of Prep1 in the alphabeta T-cell receptor T-lymphocytic potential of hematopoietic precursors.

    PubMed

    Penkov, Dmitri; Di Rosa, Patrizia; Fernandez Diaz, Luis; Basso, Veronica; Ferretti, Elisabetta; Grassi, Fabio; Mondino, Anna; Blasi, Francesco

    2005-12-01

    Prep1 is a homeodomain transcription factor that acts by dimerizing with Pbx. Since Prep1 null embryos die at gastrulation, we studied Prep1(i/i) hypomorphic mice to study the physiological role of Prep1. A low percentage of homozygous Prep1(i/i) mice survived at birth, and their postnatal functions could be investigated. Reduced Prep1 expression caused an abnormal thymic T-cell development: increased CD4(-) CD8(-) double-negative thymocytes, decrease in alphabetaTCR(high) cells (cells with high levels of the alphabetaTau-cell receptor [alphabetaTCR]) and CD4(+) and CD8(+) single-positive (SP) thymocytes, and increase in gammadeltaTCR cells. Peripheral lymphoid organs of Prep1(i/i) mice contained fewer alphabetaTCR mature T cells and more gammadeltaTCR T cells than wild-type littermates. Moreover, Prep1(i/i) CD4(+) CD8(+) double-positive thymocytes underwent more apoptosis, and SP thymocytes proliferated less than control littermates. Mice that were lethally irradiated and then had Prep1(i/i) fetal liver cells transplanted showed the same defects as the Prep1(i/i) mice did. Among PBC family members, Pbx2 and very low levels of Pbx3 were observed in the thymi of wild-type mice. In Prep1(i/i) mice, the level of Pbx2 protein was profoundly decreased, while for Pbx3 no definitive conclusion could be reached. Therefore, the deficient postnatal T-lymphocytic potential of the Prep1 hematopoietic progenitors depends on the combined, not compensated, absence of Prep1 and at least Pbx2. PMID:16314502

  2. Homeostatic action of adenosine A3 and A1 receptor agonists on proliferation of hematopoietic precursor cells.

    PubMed

    Hofer, Michal; Pospísil, Milan; Znojil, Vladimír; Holá, Jirina; Streitová, Denisa; Vacek, Antonín

    2008-07-01

    Two adenosine receptor agonists, N6-(3-iodobenzyl)adenosine-5'-N-methyluronamide (IB-MECA) and N6-cyclopentyladenosine (CPA), which selectively activate adenosine A3 and A1 receptors, respectively, were tested for their ability to influence proliferation of granulocytic and erythroid cells in femoral bone marrow of mice using morphological criteria. Agonists were given intraperitoneally to mice in repeated isomolar doses of 200 nmol/kg. Three variants of experiments were performed to investigate the action of the agonists under normal resting state of mice and in phases of cell depletion and subsequent regeneration after treatment with the cytotoxic drug 5-fluorouracil. In the case of granulopoiesis, IB-MECA 1) increased by a moderate but significant level proliferation of cells under normal resting state; 2) strongly increased proliferation of cells in the cell depletion phase; but 3) did not influence cell proliferation in the regeneration phase. CPA did not influence cell proliferation under normal resting state and in the cell depletion phase, but strongly suppressed the overshooting cell proliferation in the regeneration phase. The stimulatory effect of IB-MECA on cell proliferation of erythroid cells was observed only when this agonist was administered during the cell depletion phase. CPA did not modulate erythroid proliferation in any of the functional states investigated, probably due to the lower demand for cell production as compared with granulopoiesis. The results indicate opposite effects of the two adenosine receptor agonists on proliferation of hematopoietic cells and suggest the plasticity and homeostatic role of the adenosine receptor expression. PMID:18445770

  3. Differentiation of M1 Myeloid Precursor Cells into Macrophages Results in Binding and Infection by Theiler’s Murine Encephalomyelitis Virus and Apoptosis

    PubMed Central

    Jelachich, M. L.; Bramlage, C.; Lipton, H. L.

    1999-01-01

    Infection of susceptible mouse strains with BeAn, a less virulent strain of Theiler’s murine encephalomyelitis virus (TMEV), results in immune system-mediated demyelinating lesions in the central nervous system (CNS) similar to those in multiple sclerosis. Since macrophages appear to carry the major detectable antigen burden in vivo, and purification of sufficient cell numbers from the CNS for detailed analysis is difficult, macrophage-like cell lines provide an accessible system with which to study virus-macrophage interactions. The myeloid precursor cell line M1 differentiates in response to cytokines and expresses many characteristics of tissue macrophages. Incubation of TMEV with undifferentiated M1 cells produced neither infection nor apoptosis, whereas differentiated M1 (M1-D) cells developed a restricted virus infection and changes indicative of apoptosis. Virus binding and RNA replication as well as cellular production of alpha/beta interferons increased with differentiation. Although the amount of infectious virus was highly restricted, BeAn-infected M1-D cells synthesized and appropriately processed virus capsid proteins at levels comparable to those for permissive BHK-21 cells. Analysis of Bcl-2 protein family expression in undifferentiated and differentiated cells suggests that susceptibility of M1-D cells to apoptosis may be controlled, in part, by expression of the proapoptotic α isoform of Bax and Bak. These data suggest that macrophage differentiation plays a role in susceptibility to TMEV infection and apoptosis. PMID:10074176

  4. Myeloid cells and lymphangiogenesis.

    PubMed

    Zumsteg, Adrian; Christofori, Gerhard

    2012-06-01

    The lymphatic vascular system and the hematopoietic system are intimately connected in ontogeny and in physiology. During embryonic development, mammalian species derive a first lymphatic vascular plexus from the previously formed anterior cardinal vein, whereas birds and amphibians have a lymphatic vascular system of dual origin, composed of lymphatic endothelial cells (LECs) of venous origin combined with LECs derived from mesenchymal lymphangioblasts. The contribution of hematopoietic cells as building blocks of nascent lymphatic structures in mammals is still under debate. In contrast, the importance of myeloid cells to direct lymphatic vessel growth and function postnatally has been experimentally shown. For example, myeloid cells communicate with LECs via paracrine factors or cell-cell contacts, and they also can acquire lymphatic endothelial morphology and marker gene expression, a process reminiscent of developmental vasculogenesis. Here, we present an overview of the current understanding of how lymphatic vessels and the hematopoietic system, in particular myeloid cells, interact during embryonic development, in normal organ physiology, and in disease. PMID:22675661

  5. Allogeneic hematopoietic cell transplantation after conditioning with I-131-anti-CD45 antibody plus fludarabine and low-dose total body irradiation for elderly patients with advanced acute myeloid leukemia or high-risk myelodysplastic syndrome.

    SciTech Connect

    Pagel, John M.; Gooley, T. A.; Rajendran, Joseph G.; Fisher, Darrell R.; Wilson, Wendy A.; Sandmaier, B. M.; Matthews, D. C.; Deeg, H. Joachim; Gopal, Ajay K.; Martin, P. J.; Storb, R.; Press, Oliver W.; Appelbaum, Frederick R.

    2009-12-24

    We conducted a study to estimate the maximum tolerated dose (MTD) of I-131-anti-CD45 antibody (Ab; BC8) that can be combined with a standard reduced-intensity conditioning regimen before allogeneic hematopoietic cell transplantation. Fifty-eight patients older than 50 years with advanced acute myeloid leukemia (AML) or high-risk myelodysplastic syndrome (MDS) were treated with (131)I-BC8 Ab and fludarabine plus 2 Gy total body irradiation. Eighty-six percent of patients had AML or MDS with greater than 5% marrow blasts at the time of transplantation. Treatment produced a complete remission in all patients, and all had 100% donor-derived CD3(+) and CD33(+) cells in the blood by day 28 after the transplantation. The MTD of I-131-BC8 Ab delivered to liver was estimated to be 24 Gy. Seven patients (12%) died of nonrelapse causes by day 100. The estimated probability of recurrent malignancy at 1 year is 40%, and the 1-year survival estimate is 41%. These results show that CD45-targeted radiotherapy can be safely combined with a reduced-intensity conditioning regimen to yield encouraging overall survival for older, high-risk patients with AML or MDS. This study was registered at www.clinicaltrials.gov as #NCT00008177.

  6. Loss of Snail2 favors skin tumor progression by promoting the recruitment of myeloid progenitors

    PubMed Central

    Villarejo, Ana; Molina-Ortiz, Patricia; Montenegro, Yenny; Moreno-Bueno, Gema; Morales, Saleta; Santos, Vanesa; Gridley, Tom; Pérez-Moreno, Mirna A.; Peinado, Héctor; Portillo, Francisco; Calés, Carmela; Cano, Amparo

    2015-01-01

    Snail2 is a zinc finger transcription factor involved in driving epithelial to mesenchymal transitions. Snail2 null mice are viable, but display defects in melanogenesis, gametogenesis and hematopoiesis, and are markedly radiosensitive. Here, using mouse genetics, we have studied the contributions of Snail2 to epidermal homeostasis and skin carcinogenesis. Snail2 −/− mice presented a defective epidermal terminal differentiation and, unexpectedly, an increase in number, size and malignancy of tumor lesions when subjected to the two-stage mouse skin chemical carcinogenesis protocol, compared with controls. Additionally, tumor lesions from Snail2 −/− mice presented a high inflammatory component with an elevated percentage of myeloid precursors in tumor lesions that was further increased in the presence of the anti-inflammatory agent dexamethasone. In vitro studies in Snail2 null keratinocytes showed that loss of Snail2 leads to a decrease in proliferation indicating a non-cell autonomous role for Snail2 in the skin carcinogenic response observed in vivo. Bone marrow (BM) cross-reconstitution assays between Snail2 wild-type and null mice showed that Snail2 absence in the hematopoietic system fully reproduces the tumor behavior of the Snail2 null mice and triggers the accumulation of myeloid precursors in the BM, blood and tumor lesions. These results indicate a new role for Snail2 in preventing myeloid precursors recruitment impairing skin chemical carcinogenesis progression. PMID:25784375

  7. Loss of Snail2 favors skin tumor progression by promoting the recruitment of myeloid progenitors.

    PubMed

    Villarejo, Ana; Molina-Ortiz, Patricia; Montenegro, Yenny; Moreno-Bueno, Gema; Morales, Saleta; Santos, Vanesa; Gridley, Tom; Pérez-Moreno, Mirna A; Peinado, Héctor; Portillo, Francisco; Calés, Carmela; Cano, Amparo

    2015-05-01

    Snail2 is a zinc finger transcription factor involved in driving epithelial to mesenchymal transitions. Snail2 null mice are viable, but display defects in melanogenesis, gametogenesis and hematopoiesis, and are markedly radiosensitive. Here, using mouse genetics, we have studied the contributions of Snail2 to epidermal homeostasis and skin carcinogenesis. Snail2 (-/-) mice presented a defective epidermal terminal differentiation and, unexpectedly, an increase in number, size and malignancy of tumor lesions when subjected to the two-stage mouse skin chemical carcinogenesis protocol, compared with controls. Additionally, tumor lesions from Snail2 (-/-) mice presented a high inflammatory component with an elevated percentage of myeloid precursors in tumor lesions that was further increased in the presence of the anti-inflammatory agent dexamethasone. In vitro studies in Snail2 null keratinocytes showed that loss of Snail2 leads to a decrease in proliferation indicating a non-cell autonomous role for Snail2 in the skin carcinogenic response observed in vivo. Bone marrow (BM) cross-reconstitution assays between Snail2 wild-type and null mice showed that Snail2 absence in the hematopoietic system fully reproduces the tumor behavior of the Snail2 null mice and triggers the accumulation of myeloid precursors in the BM, blood and tumor lesions. These results indicate a new role for Snail2 in preventing myeloid precursors recruitment impairing skin chemical carcinogenesis progression. PMID:25784375

  8. Long-term outcomes of patients with intermediate-risk acute myeloid leukemia treated with autologous hematopoietic cell transplant in first complete remission.

    PubMed

    Mannis, Gabriel N; Martin, Thomas G; Damon, Lloyd E; Logan, Aaron C; Olin, Rebecca L; Flanders, Michael D; Ai, Weiyun Z; Gaensler, Karin M L; Kaplan, Lawrence D; Sayre, Peter H; Smith, Catherine C; Wolf, Jeffrey L; Andreadis, Charalambos

    2016-07-01

    In 2014, autologous hematopoietic cell transplant (autoHCT) was removed from the National Comprehensive Cancer Network guidelines as a recommended treatment for patients with intermediate-risk AML in first complete remission (CR1). We reviewed the outcomes of all patients with intermediate-risk AML treated with autoHCT in CR1 at our institution. Of 334 patients who underwent autoHCT for AML between 1988 and 2013, 133 patients with intermediate-risk AML in CR1 were identified. Cytogenetics were diploid in 97 (73%). With a median follow-up of 4.1 years (range 0.1-17), median overall survival (OS) is 6.7 years; at 5 years post-transplant, 59% of patients remain alive and 43% remain relapse-free. Forty-eight percent of relapsing patients proceeded to salvage alloHCT. Our findings demonstrate that nearly half of patients with intermediate-risk AML in CR1 achieve sustained remissions, and that salvage alloHCT is feasible in those who relapse. AutoHCT therefore remains a reasonable option for intermediate-risk patients with AML in CR1. PMID:26490487

  9. Myeloid-derived Suppressor Cells Adhere to Physiologic STAT3- vs STAT5-dependent Hematopoietic Programming, Establishing Diverse Tumor-Mediated Mechanisms of Immunologic Escape

    PubMed Central

    Cohen, Peter A.; Ko, Jennifer S.; Storkus, Walter J.; Spencer, Christopher D.; Bradley, Judy M.; Gorman, Jessica E.; McCurry, Dustin B.; Zorro-Manrique, Soroya; Dominguez, Anna Lucia; Pathangey, Latha B.; Rayman, Patricia A.; Rini, Brian I.; Gendler, Sandra J.; Finke, James H.

    2013-01-01

    The receptor tyrosine kinase inhibitor, sunitinib, is astonishingly effective in its capacity to reduce MDSCs in peripheral tissues such as blood (human) and spleen (mouse), restoring responsiveness of bystander T lymphocytes to TcR stimulation. Sunitinib blocks proliferation of undifferentiated MDSCs and decreases survival of more differentiated neutrophilic MDSC (n-MDSC) progeny. Ironically, sunitinib’s profound effects are observed even in a total absence of detectable anti-tumor therapeutic response. This is best explained by the presence of disparate MDSC-conditioning stimuli within individual body compartments, allowing sensitivity and resistance to sunitinib to coexist within the same mouse or patient. The presence or absence of GM-CSF is likely the major determinant in each compartment, given that GM-CSF’s capacity to preempt STAT3-dependent with dominant STAT5-dependent hematopoietic programming confers sunitinib resistance and redirects differentiation from the n-MDSC lineage to the more versatile monocytoid (m-MDSC) lineage. The clinical sunitinib experience underscores that strategies for MDSC and Treg depletions must be mindful of disparities among body compartments to avoid sanctuary effects. Ironically, m-MDSCs manifesting resistance to sunitinib also have the greatest potential to differentiate into tumoricidal accessory cells, by virtue of their capacity to respond to T cell-secreted IFN-γ or to TLR agonists with nitric oxide and peroxynitrate production. PMID:23017141

  10. DNA methylation in hematopoietic development and disease.

    PubMed

    Gore, Aniket V; Weinstein, Brant M

    2016-09-01

    DNA methylation is an important epigenetic modification that can have profound and widespread effects on gene expression and on cellular fate and function. Recent work has indicated that DNA methylation plays a critical role in hematopoietic development and hematopoietic disease. DNA methyltransferases and Ten-eleven translocation enzymes are required to add and remove methyl "marks" from DNA, respectively, and both sets of genes have been found necessary for proper formation and maintenance of hematopoietic stem cells and for differentiation of downstream hematopoietic lineages during development. DNA methylation and demethylation enzymes have also been implicated in hematopoietic disorders such as acute myeloid leukemia and myelodysplastic syndrome. Here, we review some of the recent literature regarding the role of DNA methylation in hematopoietic health and disease. PMID:27178734

  11. Idarubicin-intensified BUCY2 conditioning regimen improved survival in high-risk acute myeloid, but not lymphocytic leukemia patients undergoing allogeneic hematopoietic stem cell transplantation: A retrospective comparative study.

    PubMed

    Fang, Jun; Zhang, Ran; Wang, Huafang; Hong, Mei; Wu, Qiuling; Nie, Dimin; You, Yong; Zhong, Zhaodong; Li, Weiming; Hu, Yu; Xia, Linghui

    2016-07-01

    The intensity of conditioning regimen is highly correlated with outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT). We have previously reported that idarubicin (IDA) intensified BUCY2 regimen could reduce relapse and improve survival for high-risk hematological malignancies undergoing allo-HSCT. However, there is no published study comparing the efficacy of IDA-BUCY2 regimen for high-risk acute myeloid leukemia (AML) versus acute lymphocytic leukemia (ALL). We further retrospectively compared therapeutic outcomes of intensified conditioning regimen on 140 high-risk AML and ALL patients in the data analyses. IDA 15mg/m(2)/d was administered by continuous infusion from day -11 to -9, followed by intravenous injection of busulfan (BU) (3.2mg/kg/d) from day -6 to -4, and intravenous injection of cyclophosphamide (CY) (1.8g/m(2)/d) from day -3 to -2 in IDA-BUCY2 regimen. For high-risk AML, cumulative probabilities of 3-year relapse rates in IDA-BUCY2 and traditional BUCY2 regimens were 16.9%, 43.3% (P=0.016). Cumulative probabilities of 3-year overall survival (OS) and disease-free survival (DFS) were 69.2% vs 44.0% (P=0.024), and 66.9% vs 38.2% (P=0.01). However, two regimens showed no significant differences for high-risk ALL. Multivariate analysis also indicated that IDA intensified BUCY2 conditioning was the favorable variable to reduce relapse and elevate survival for high-risk AML patients. In conclusion, IDA-BUCY2 regimen reduces relapse and improves survival for high-risk AML undergoing allo-HSCT, but not presenting uniform therapeutic effects for high-risk ALL. PMID:27131062

  12. Phase II Trial of Reduced-Intensity Busulfan/Clofarabine Conditioning with Allogeneic Hematopoietic Stem Cell Transplantation for Patients with Acute Myeloid Leukemia, Myelodysplastic Syndromes, and Acute Lymphoid Leukemia.

    PubMed

    El-Jawahri, Areej; Li, Shuli; Ballen, Karen K; Cutler, Corey; Dey, Bimalangshu R; Driscoll, Jessica; Hunnewell, Chrisa; Ho, Vincent T; McAfee, Steven L; Poliquin, Cathleen; Saylor, Meredith; Soiffer, Robert J; Spitzer, Thomas R; Alyea, Edwin; Chen, Yi-Bin

    2016-01-01

    Clofarabine has potent antileukemia activity and its inclusion in reduced-intensity conditioning (RIC) allogeneic hematopoietic stem cell transplantation (HSCT) for acute leukemia could potentially improve outcomes. We conducted a phase II study of busulfan (.8 mg/kg i.v. twice daily on days -5, -4, -3, and -2) with clofarabine (40 mg/m(2) i.v. daily on days -5, -4, -3, and -2) conditioning before allogeneic 8/8 HLA-matched related or unrelated HSCT. The primary endpoint was donor neutrophil engraftment by day +40. Secondary endpoints included nonrelapse mortality (NRM), acute and chronic graft-versus-host disease (GVHD), progression-free survival (PFS), and overall survival (OS). Thirty-four patients (acute myeloid leukemia [AML], n = 25; myelodysplastic syndromes, n = 5; and acute lymphoid leukemia, n = 4) were enrolled. Day 40+ engraftment with donor chimerism was achieved in 33 of 34 patients with 1 patient dying before count recovery. Day 100 and 1-year NRM were 5.9% (95% confidence interval [CI], 1.0 to 17.4) and 24% (95% CI, 11 to 39), respectively. The 2-year relapse rate was 26% (95% CI, 13 to 42). Cumulative incidences of acute and chronic GVHD were 21% and 44%, respectively. The 2-year PFS was 50% (95% CI, 32 to 65) and OS was 56% (95% CI, 38 to 71). For patients with AML in first complete remission, 2-year PFS and OS were both 82% (95% CI, 55 to 94). RIC with busulfan and clofarabine leads to successful engraftment with acceptable rates of NRM and GVHD. PMID:26260679

  13. Comparison of reduced-intensity and myeloablative conditioning regimens for allogeneic hematopoietic stem cell transplantation in patients with acute myeloid leukemia and acute lymphoblastic leukemia: a meta-analysis.

    PubMed

    Abdul Wahid, S Fadilah; Ismail, Nor-Azimah; Mohd-Idris, Mohd-Razif; Jamaluddin, Fariza Wan; Tumian, NorRafeah; Sze-Wei, Ernie Yap; Muhammad, Norasiah; Nai, Ming Lai

    2014-11-01

    Currently, the indications to perform reduced-intensity conditioning allogeneic hematopoietic stem cell transplant (RIC-HCT) are based on data derived mainly from large registry and single-centre retrospective studies. Thus, at the present time, there is limited direct evidence supporting the current practice in selecting patients with acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) for RIC versus myeloablative conditioning (MAC) transplants. To determine the relationship between dose intensity of conditioning regimen and survival outcomes after allografting in AML/ALL patients, we performed a meta-analysis of 23 clinical trials reported between 1990 and 2013 involving 15,258 adult patients that compare survival outcomes after RIC-HCT versus MAC-HCT. RIC-HCT resulted in comparable <2-year and 2-6 year overall survival (OS) rates post-transplantation even though the RIC-HCT recipients were older and had more active disease than MAC-HCT recipients. The 2-6 year progression-free survival (PFS), nonrelapse mortality, acute graft-versus-host disease (GvHD) and chronic GvHD rates were reduced after RIC-HCT, but relapse rate was increased. Similar outcomes were observed regardless of disease type and status at transplantation. Odds ratio for all outcomes remained comparable with or without performing separate analyses for the year of HCT and for retrospective versus prospective studies. Among RIC-HCT recipients, survival rates were superior if patients were in CR at transplantation. Significant inter-study heterogeneity for aGvHD data and publication bias for PFS data were observed. This meta-analysis showed no OS benefit of MAC-HCT over RIC-HCT across the entire cohort of patients suggesting that RIC-HCT could be an effective therapeutic option for AML/ALL patients who are ineligible for MAC-HCT and CR status is preferred before RIC-HCT. PMID:25072307

  14. Comparison of Reduced-Intensity and Myeloablative Conditioning Regimens for Allogeneic Hematopoietic Stem Cell Transplantation in Patients with Acute Myeloid Leukemia and Acute Lymphoblastic Leukemia: A Meta-Analysis

    PubMed Central

    Ismail, Nor-Azimah; Mohd-Idris, Mohd-Razif; Jamaluddin, Fariza Wan; Tumian, NorRafeah; Sze-Wei, Ernie Yap; Muhammad, Norasiah; Nai, Ming Lai

    2014-01-01

    Currently, the indications to perform reduced-intensity conditioning allogeneic hematopoietic stem cell transplant (RIC-HCT) are based on data derived mainly from large registry and single-centre retrospective studies. Thus, at the present time, there is limited direct evidence supporting the current practice in selecting patients with acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) for RIC versus myeloablative conditioning (MAC) transplants. To determine the relationship between dose intensity of conditioning regimen and survival outcomes after allografting in AML/ALL patients, we performed a meta-analysis of 23 clinical trials reported between 1990 and 2013 involving 15,258 adult patients that compare survival outcomes after RIC-HCT versus MAC-HCT. RIC-HCT resulted in comparable <2-year and 2–6 year overall survival (OS) rates post-transplantation even though the RIC-HCT recipients were older and had more active disease than MAC-HCT recipients. The 2–6 year progression-free survival (PFS), nonrelapse mortality, acute graft-versus-host disease (GvHD) and chronic GvHD rates were reduced after RIC-HCT, but relapse rate was increased. Similar outcomes were observed regardless of disease type and status at transplantation. Odds ratio for all outcomes remained comparable with or without performing separate analyses for the year of HCT and for retrospective versus prospective studies. Among RIC-HCT recipients, survival rates were superior if patients were in CR at transplantation. Significant inter-study heterogeneity for aGvHD data and publication bias for PFS data were observed. This meta-analysis showed no OS benefit of MAC-HCT over RIC-HCT across the entire cohort of patients suggesting that RIC-HCT could be an effective therapeutic option for AML/ALL patients who are ineligible for MAC-HCT and CR status is preferred before RIC-HCT. PMID:25072307

  15. Effect of Age on Outcome of Reduced-Intensity Hematopoietic Cell Transplantation for Older Patients With Acute Myeloid Leukemia in First Complete Remission or With Myelodysplastic Syndrome

    PubMed Central

    McClune, Brian L.; Weisdorf, Daniel J.; Pedersen, Tanya L.; Tunes da Silva, Gisela; Tallman, Martin S.; Sierra, Jorge; DiPersio, John; Keating, Armand; Gale, Robert P.; George, Biju; Gupta, Vikas; Hahn, Theresa; Isola, Luis; Jagasia, Madan; Lazarus, Hillard; Marks, David; Maziarz, Richard; Waller, Edmund K.; Bredeson, Chris; Giralt, Sergio

    2010-01-01

    Purpose Acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS) primarily afflict older individuals. Hematopoietic cell transplantation (HCT) is generally not offered because of concerns of excess morbidity and mortality. Reduced-intensity conditioning (RIC) regimens allow increased use of allogeneic HCT for older patients. To define prognostic factors impacting long-term outcomes of RIC regimens in patients older than age 40 years with AML in first complete remission or MDS and to determine the impact of age, we analyzed data from the Center for International Blood and Marrow Transplant Research (CIBMTR). Patients and Methods We reviewed data reported to the CIBMTR (1995 to 2005) on 1,080 patients undergoing RIC HCT. Outcomes analyzed included neutrophil recovery, incidence of acute or chronic graft-versus-host disease (GVHD), nonrelapse mortality (NRM), relapse, disease-free survival (DFS), and overall survival (OS). Results Univariate analyses demonstrated no age group differences in NRM, grade 2 to 4 acute GVHD, chronic GVHD, or relapse. Patients age 40 to 54, 55 to 59, 60 to 64, and ≥ 65 years had 2-year survival rates as follows: 44% (95% CI, 37% to 52%), 50% (95% CI, 41% to 59%), 34% (95% CI, 25% to 43%), and 36% (95% CI, 24% to 49%), respectively, for patients with AML (P = .06); and 42% (95% CI, 35% to 49%), 35% (95% CI, 27% to 43%), 45% (95% CI, 36% to 54%), and 38% (95% CI, 25% to 51%), respectively, for patients with MDS (P = .37). Multivariate analysis revealed no significant impact of age on NRM, relapse, DFS, or OS (all P > .3). Greater HLA disparity adversely affected 2-year NRM, DFS, and OS. Unfavorable cytogenetics adversely impacted relapse, DFS, and OS. Better pre-HCT performance status predicted improved 2-year OS. Conclusion With these similar outcomes observed in older patients, we conclude that older age alone should not be considered a contraindication to HCT. PMID:20212255

  16. Angiogenin Defines Heterogeneity at the Core of the Hematopoietic Niche.

    PubMed

    Di Scala, Marianna; Hidalgo, Andrés

    2016-09-01

    Successful hematopoietic regeneration demands preservation of stemness while enabling expansion and differentiation into blood lineages. Now, Silberstein et al. (2016) and Goncalves et al. (2016) identify a ribonuclease secreted by proximal niche cells that simultaneously drives quiescence of HSCs and proliferation of myeloid progenitors and dramatically enhances hematopoietic recovery after HSC transplantation. PMID:27588743

  17. Phase II Study of Haploidentical Natural Killer Cell Infusion for Treatment of Relapsed or Persistent Myeloid Malignancies Following Allogeneic Hematopoietic Cell Transplantation.

    PubMed

    Shaffer, Brian C; Le Luduec, Jean-Benoit; Forlenza, Christopher; Jakubowski, Ann A; Perales, Miguel-Angel; Young, James W; Hsu, Katharine C

    2016-04-01

    We conducted a phase 2 study to determine the efficacy of HLA-haploidentical related donor natural killer (NK) cells after cyclophosphamide-based lymphodepletion in patients with relapsed or progressive acute myelogenous leukemia (AML) or myelodysplastic syndrome (MDS) following allogeneic hematopoietic cell transplantation (HCT). Eight patients (2 with MDS and 6 with AML) were treated with cyclophosphamide 50 mg/kg on day -3 and day -2 before infusion of NK cells isolated from a haploidentical related donor. One patient also received fludarabine 25 mg/m(2)/day for 4 days. Six doses of 1 million units of interleukin-2 (IL-2) were administered on alternating days beginning on day -1. The median number of NK cells infused was 10.6 × 10(6)/kg (range, 4.3 to 22.4 × 10(6)/kg), and the median number of CD3 cells infused was 2.1 × 10(3)/kg (range, 1.9 to 40 × 10(3)/kg). NK infusions were well tolerated, with a median time to neutrophil recovery of 19 days (range, 7 days to not achieved) and no incidence of graft-versus-host disease after NK infusion. One patient with AML and 1 patient with MDS achieved a complete response, but relapsed at 1.7 and 1.8 months, respectively. One patient with MDS experienced resolution of dysplastic features but persistence of clonal karyotype abnormalities; this patient was stable at 65 months after NK cell therapy. The median duration of survival was 12.9 months (range, 0.8 to 65.3 months). Chimerism analysis of CD3(-)/CD56(+) peripheral blood cells did not detect any circulating haploidentical NK cells after infusion. NK phenotyping was performed in 7 patients during and after IL-2 infusion. We found a slight trend toward greater expression of KIR2DL2/2DL3/2DS2 (5% versus 28%; P = .03) at 14 days in patients who survived longer than 6 months from NK cell infusion (n = 4) compared with those who died within 6 months of NK cell therapy (n = 3). In summary, our data support the safety of haploidentical NK cell

  18. FLT3 ligand administration after hematopoietic cell transplantation increases circulating dendritic cell precursors that can be activated by CpG oligodeoxynucleotides to enhance T-cell and natural killer cell function.

    PubMed

    Chen, Wei; Chan, Anissa S H; Dawson, Amanda J; Liang, Xueqing; Blazar, Bruce R; Miller, Jeffrey S

    2005-01-01

    Dendritic cells (DCs) are key effectors in innate immunity and play critical roles in triggering adaptive immune responses. FLT3 ligand (FLT3-L) is essential for DC development from hematopoietic progenitors. In a phase I clinical trial, we demonstrated that immunotherapy with subcutaneous injection of FLT3-L is safe and well tolerated in cancer patients recovering from autologous hematopoietic cell transplantation (HCT). FLT3-L administration significantly increased the frequency and absolute number of blood DC precursors without affecting other mature cell lineages during the 6-week course of FLT3-L therapy. After 14 days of FLT3-L administration, the number of blood CD11c + DCs, plasmacytoid DCs (PDCs), and CD14 + monocytes increased by 5.3-, 2.9-, 3.8-fold, respectively, and was maintained at increased levels throughout FLT3-L therapy. FLT3-L-increased blood DCs in HCT patients were immature and had modest enhancing effects on in vitro T-cell proliferation to antigens and natural killer (NK) cell function. The addition of type B CpG oligodeoxynucleotides (ODNs) to peripheral blood mononuclear cells obtained from HCT patients receiving FLT3-L therapy induced rapid maturation of both CD11c + DCs and PDCs and enhanced T-cell proliferative responses. In addition, CpG ODN induced potent activation of NK cells from FLT3-L-treated patients with increased surface CD69 expression and augmented cytotoxicity. CpG ODN-induced activation of NK cells was primarily via an indirect mechanism through PDCs. These findings suggest that FLT3-L mobilization of DC precursors followed by a specific DC stimulus such as CpG ODN may provide a novel strategy to manipulate antitumor immunity in patients after HCT. PMID:15625541

  19. Cytokine Signaling and Hematopoietic Homeostasis Are Disrupted in Lnk-deficient Mice

    PubMed Central

    Velazquez, Laura; Cheng, Alec M.; Fleming, Heather E.; Furlonger, Caren; Vesely, Shirly; Bernstein, Alan; Paige, Christopher J.; Pawson, Tony

    2002-01-01

    The adaptor protein Lnk, and the closely related proteins APS and SH2B, form a subfamily of SH2 domain-containing proteins implicated in growth factor, cytokine, and immunoreceptor signaling. To elucidate the physiological function of Lnk, we derived Lnk-deficient mice. Lnk−/− mice are viable, but display marked changes in the hematopoietic compartment, including splenomegaly and abnormal lymphoid and myeloid homeostasis. The in vitro proliferative capacity and absolute numbers of hematopoietic progenitors from Lnk−/− mice are greatly increased, in part due to hypersensitivity to several cytokines. Moreover, an increased synergy between stem cell factor and either interleukin (IL)-3 or IL-7 was observed in Lnk−/− cells. Furthermore, Lnk inactivation causes abnormal modulation of IL-3 and stem cell factor–mediated signaling pathways. Consistent with these results, we also show that Lnk is highly expressed in multipotent cells and committed precursors in the erythroid, megakaryocyte, and myeloid lineages. These data implicate Lnk as playing an important role in hematopoiesis and in the regulation of growth factor and cytokine receptor–mediated signaling. PMID:12070287

  20. Differentiation and characterization of myeloid cells.

    PubMed

    Gupta, Dipti; Shah, Hetavi Parag; Malu, Krishnakumar; Berliner, Nancy; Gaines, Peter

    2014-01-01

    Ex vivo differentiation of myeloid cells begins with an enriched population of bone marrow-derived hematopoietic stem cells generated by lineage depletion and/or positive selection for CD34(+) antigen (human) or Sca-1(+) (mouse) cells, which are then expanded and subsequently induced in vitro in a process that recapitulates normal myeloid development. Myeloid cell lines include two human leukemic cell lines, NB-4 and HL-60, which have been demonstrated to undergo retinoic acid-induced myeloid development; however, both cell lines exhibit defects in the up-regulation of late-expressed neutrophil-specific genes. Multiple murine factor-dependent cell models of myelopoiesis are also available that express the full range of neutrophil maturation markers, including: 32Dcl3 cells, which undergo G-CSF-induced myeloid maturation; EML/EPRO cells, which develop into mature neutrophils in response to cytokines and retinoic acid; and ER-Hoxb8 cells, which undergo myeloid maturation upon removal of estradiol in the maintenance medium. In this unit, the induction of myeloid maturation in each of these model systems is described, including their differentiation to either neutrophils or macrophages, if applicable. Commonly used techniques to test for myeloid characteristics of developing cells are also described, including flow cytometry and real time RT-PCR. PMID:24510620

  1. C-Myb(+) erythro-myeloid progenitor-derived fetal monocytes give rise to adult tissue-resident macrophages.

    PubMed

    Hoeffel, Guillaume; Chen, Jinmiao; Lavin, Yonit; Low, Donovan; Almeida, Francisca F; See, Peter; Beaudin, Anna E; Lum, Josephine; Low, Ivy; Forsberg, E Camilla; Poidinger, Michael; Zolezzi, Francesca; Larbi, Anis; Ng, Lai Guan; Chan, Jerry K Y; Greter, Melanie; Becher, Burkhard; Samokhvalov, Igor M; Merad, Miriam; Ginhoux, Florent

    2015-04-21

    Although classified as hematopoietic cells, tissue-resident macrophages (MFs) arise from embryonic precursors that seed the tissues prior to birth to generate a self-renewing population, which is maintained independently of adult hematopoiesis. Here we reveal the identity of these embryonic precursors using an in utero MF-depletion strategy and fate-mapping of yolk sac (YS) and fetal liver (FL) hematopoiesis. We show that YS MFs are the main precursors of microglia, while most other MFs derive from fetal monocytes (MOs). Both YS MFs and fetal MOs arise from erythro-myeloid progenitors (EMPs) generated in the YS. In the YS, EMPs gave rise to MFs without monocytic intermediates, while EMP seeding the FL upon the establishment of blood circulation acquired c-Myb expression and gave rise to fetal MOs that then seeded embryonic tissues and differentiated into MFs. Thus, adult tissue-resident MFs established from hematopoietic stem cell-independent embryonic precursors arise from two distinct developmental programs. PMID:25902481

  2. Colony-Stimulating Factor-1-Responsive Macrophage Precursors Reside in the Amphibian (Xenopus laevis) Bone Marrow Rather than the Hematopoietic Sub-Capsular Liver

    PubMed Central

    Grayfer, Leon; Robert, Jacques

    2013-01-01

    Macrophage precursors originate from, and undergo lineage commitment within designated sites of hematopoiesis, such as the mammalian bone marrow. These cells subsequently differentiate in response to stimulation with macrophage colony-stimulating factor (CSF-1). The amphibian bone marrow, unlike that of mammals, has been overlooked as a source of leukocyte precursors in favor of the liver sub-capsular region, where hematopoiesis occurs in anurans. Here we report that the bone marrow rather than the liver periphery provides macrophage progenitors to the amphibian Xenopus laevis. We identified the amphibian CSF-1, examined its gene expression in developing and virally infected X. laevis and produce it in recombinant form (rXlCSF-1). This rXlCSF-1 did not bind or elicit proliferation/differentiation of sub-cortical liver cells. Surprisingly, a sub-population of bone marrow cells engaged this growth factor and formed rXlCSF-1-concentration-dependant colonies in semi-solid medium. Furthermore, rXlCSF-1-treated bone marrow (but not liver) cultures comprised of cells with characteristic macrophage morphology and high gene expression of the macrophage marker, colony stimulating factor-1 receptor (CSF-1R). Together, our findings indicate that in contrast to all other vertebrates studied to date, Xenopus committed macrophage precursors populations are not present in the central site of hematopoiesis, but reside in the bone marrow. PMID:23485675

  3. Parvovirus Infection Suppresses Long-Term Repopulating Hematopoietic Stem Cells

    PubMed Central

    Segovia, José C.; Guenechea, Guillermo; Gallego, Jesús M.; Almendral, José M.; Bueren, Juan A.

    2003-01-01

    The functional disturbance of self-renewing and multipotent hematopoietic stem cells (HSCs) in viral diseases is poorly understood. In this report, we have assessed the susceptibility of mouse HSCs to strain i of the autonomous parvovirus minute virus of mice (MVMi) in vitro and during persistent infection of an immunodeficient host. Purified 5FUr Lin− Sca-1+ primitive hematopoietic precursors were permissive for MVMi genome replication and the expression of viral gene products. The lymphoid and myeloid repopulating capacity of bone marrow (BM) cells was significantly impaired after in vitro infection, although the degree of functional effect proportionally decreased with the posttransplantation time. This indicated that MVMi targets the heterogeneous compartment of repopulating cells with differential affinity and suggests that the virus may persist in some primitive HSCs in the quiescent stage, killing those eventually recruited for proliferative activity. Immunodeficient SCID mice oronasally infected with MVMi were cured of the characteristic virus-induced lethal leukopenia by transplantation of immunocompetent BM grafts. However, two double-stranded viral DNA species, probably uncommon replicative intermediates, remained in the marrow of every transplanted mouse months after infectious virus clearance. Genetic analysis of the rescued mice showed that the infection ensured a stable engraftment of donor hematopoiesis by markedly depleting the pool of endogenous HSCs. The MVMi-induced suppression of HSC functions illustrates the accessibility of this compartment to infection during a natural viral hematological disease. These results may provide clues to understanding delayed hematopoietic syndromes associated with persistent viral infections and to prospective gene delivery to HSCs in vivo. PMID:12857918

  4. Nf1 Haploinsufficiency Alters Myeloid Lineage Commitment and Function, Leading to Deranged Skeletal Homeostasis.

    PubMed

    Rhodes, Steven D; Yang, Hao; Dong, Ruizhi; Menon, Keshav; He, Yongzheng; Li, Zhaomin; Chen, Shi; Staser, Karl W; Jiang, Li; Wu, Xiaohua; Yang, Xianlin; Peng, Xianghong; Mohammad, Khalid S; Guise, Theresa A; Xu, Mingjiang; Yang, Feng-Chun

    2015-10-01

    Although nullizygous loss of NF1 leads to myeloid malignancies, haploinsufficient loss of NF1 (Nf1) has been shown to contribute to osteopenia and osteoporosis which occurs in approximately 50% of neurofibromatosis type 1 (NF1) patients. Bone marrow mononuclear cells of haploinsufficient NF1 patients and Nf1(+/-) mice exhibit increased osteoclastogenesis and accelerated bone turnover; however, the culprit hematopoietic lineages responsible for perpetuating these osteolytic manifestations have yet to be elucidated. Here we demonstrate that conditional inactivation of a single Nf1 allele within the myeloid progenitor cell population (Nf1-LysM) is necessary and sufficient to promote multiple osteoclast gains-in-function, resulting in enhanced osteoclastogenesis and accelerated osteoclast bone lytic activity in response to proresorptive challenge in vivo. Surprisingly, mice conditionally Nf1 heterozygous in mature, terminally differentiated osteoclasts (Nf1-Ctsk) do not exhibit any of these skeletal phenotypes, indicating a critical requirement for Nf1 haploinsufficiency at a more primitive/progenitor stage of myeloid development in perpetuating osteolytic activity. We further identified p21Ras-dependent hyperphosphorylation of Pu.1 within the nucleus of Nf1 haploinsufficient myelomonocytic osteoclast precursors, providing a novel therapeutic target for the potential treatment of NF1 associated osteolytic manifestations. PMID:25917016

  5. Adenosine A(1), A(2a), A(2b), and A(3) receptors in hematopoiesis. 1. Expression of receptor mRNA in four mouse hematopoietic precursor cells.

    PubMed

    Streitová, D; Sefc, L; Savvulidi, F; Pospísil, M; Holá, J; Hofer, M

    2010-01-01

    Four mouse bone marrow or thymus cell populations, namely granulopoietic/monocytopoietic, erythropoietic, B-lymphopoietic, and T-lymphopoietic precursor cells have been assayed by RT-PCR technique for the presence and relative amounts of adenosine A(1), A(2a), A(2b), and A(3) receptor mRNA. It has been found that (i) all four populations studied express all four adenosine receptor subtypes, (ii) the A(1), receptor is the least expressed in all populations studied, (iii) the A(3) receptor is markedly expressed in the populations of granulopoietic/monocytopoietic and erythropoietic cells, (iv) the A(2a) receptor is markedly expressed in the populations of B-lymphopoietic and T-lymphopoietic cells, and v) the A(2b) receptor does not predominate in any of the precursor cells studied. Our data offer a new possibility for the assessment of the readiness of these cells to respond, by receptor-mediated mechanisms, to adenosine or its analogs present in the tissues as a result of endogenous processes and/or following their administration. PMID:19249907

  6. MicroRNAs in Myeloid Hematological Malignancies

    PubMed Central

    Ciccone, Maria; Calin, George Adrian

    2015-01-01

    MicroRNAs are 19-24 nucleotides noncoding RNAs which silence modulate the expression of target genes by binding to the messenger RNAs. Myeloid malignancies include a broad spectrum of acute and chronic disorders originating from from the clonal transformation of a hematopoietic stem cell. Specific genetic abnormalities may define myeloid malignancies, such as translocation t(9;22) that represent the hallmark of chronic myeloid leukemia. Although next-generation sequencing pro-vided new insights in the genetic characterization and pathogenesis of myeloid neoplasms, the molecular mechanisms underlying myeloid neoplasms are lacking in most cases. Recently, several studies have demonstrated that the expression levels of specific miRNAs may vary among patients with myeloid malignancies compared with healthy individuals and partially unveiled how miRNAs participate in the leukemic transformation process. Finally, in vitro experiments and pre-clinical model provided preliminary data of the safety and efficacy of miRNA inhibitory molecules, opening new avenue in the treatment of myeloid hematological malignancies. PMID:27047254

  7. Differentiation and characterization of myeloid cells.

    PubMed

    Gaines, Peter; Berliner, Nancy

    2005-07-01

    Recent molecular studies of myeloid differentiation have utilized several in vitro models of myelopoiesis. Hematopoietic progenitors expressing the CD34+ antigen can be induced in vitro in a process that recapitulates the normal myeloid development. Two human leukemic cell lines, NB-4 and HL-60, have been demonstrated to undergo retinoic acid-induced myeloid development, however, both cell lines exhibit defects in the upregulation of late-expressed neutrophil-specific genes. In contrast, two murine factor-dependent cell models of myelopoiesis express the full range of neutrophil maturation markers: 32Dcl3 cells, which undergo G-CSF-induced myeloid maturation, and EML/EPRO cells, which develop into mature neutrophils in response to cytokines and retinoic acid. In this unit, the induction of myeloid maturation in each of these model systems is described. Commonly used techniques to test for myeloid characteristics of developing cells are also described. Together, these assays provide a solid foundation for in vitro investigations of myeloid development. PMID:18432952

  8. Differentiation and Characterization of Myeloid Cells

    PubMed Central

    Gupta, Dipti; Shah, Hetavi Parag; Malu, Krishnakumar; Berliner, Nancy; Gaines, Peter

    2015-01-01

    Recent molecular studies of myeloid differentiation have utilized several in vitro models of myelopoiesis, generated from either ex vivo differentiated bone marrow progenitors or induced immortalized myeloid cell lines. Ex vivo differentiation begins with an enriched population of bone marrow-derived hematopoietic stem cells generated by lineage depletion and/or positive selection for CD34+ antigen (human) or Sca-1+ (mouse) cells, which are then expanded and subsequently induced in vitro in a process that recapitulates normal myeloid development. Myeloid cell lines include two human leukemic cell lines, NB-4 and HL-60, which have been demonstrated to undergo retinoic acid–induced myeloid development, however, both cell lines exhibit defects in the upregulation of late-expressed neutrophil-specific genes. Multiple murine factor–dependent cell models of myelopoiesis are also available that express the full range of neutrophil maturation markers, including: 32Dcl3 cells, which undergo G-CSF-induced myeloid maturation, EML/EPRO cells, which develop into mature neutrophils in response to cytokines and retinoic acid, and ER-Hoxb8 cells, which undergo myeloid maturation upon removal of estradial in the maintenance medium. In this unit, the induction of myeloid maturation in each of these model systems is described, including their differentiation to either neutrophils or macrophages, if applicable. Commonly used techniques to test for myeloid characteristics of developing cells are also described, including flow cytometry and real time RT-PCR. Together, these assays provide a solid foundation for in vitro investigations of myeloid development with either human or mouse models. PMID:24510620

  9. Hhex is Required at Multiple Stages of Adult Hematopoietic Stem and Progenitor Cell Differentiation

    PubMed Central

    Goodings, Charnise; Smith, Elizabeth; Mathias, Elizabeth; Elliott, Natalina; Cleveland, Susan M.; Tripathi, Rati M.; Layer, Justin H.; Chen, Xi; Guo, Yan; Shyr, Yu; Hamid, Rizwan; Du, Yang; Davé, Utpal P.

    2015-01-01

    Hhex encodes a homeodomain transcription factor that is widely expressed in hematopoietic stem and progenitor cell populations. Its enforced expression induces T-cell leukemia and we have implicated it as an important oncogene in early T-cell precursor leukemias where it is immediately downstream of an LMO2-associated protein complex. Conventional Hhex knockouts cause embryonic lethality precluding analysis of adult hematopoiesis. Thus, we induced highly efficient conditional knockout (cKO) using vav-Cre transgenic mice. Hhex cKO mice were viable and born at normal litter sizes. At steady state, we observed a defect in B-cell development that we localized to the earliest B-cell precursor, the pro-B-cell stage. Most remarkably, bone marrow transplantation using Hhex cKO donor cells revealed a more profound defect in all hematopoietic lineages. In contrast, sublethal irradiation resulted in normal myeloid cell repopulation of the bone marrow but markedly impaired repopulation of T- and B-cell compartments. We noted that Hhex cKO stem and progenitor cell populations were skewed in their distribution and showed enhanced proliferation compared to WT cells. Our results implicate Hhex in the maintenance of LT-HSCs and in lineage allocation from multipotent progenitors especially in stress hematopoiesis. PMID:25968920

  10. Addition of High-Dose Cytarabine to Fludarabine-Based Conditioning for Hematopoietic Stem Cell Transplantation for Treating Fanconi Anemia Patients with Advanced Myeloid Malignancy: A Single-Center Experience and Literature Review.

    PubMed

    Aoki, Takahiro; Koh, Katsuyoshi; Ikeda, Yuhachi; Sekinaka, Yujin; Akiyama, Kosuke; Mori, Makiko; Arakawa, Yuki; Hanada, Ryoji

    2016-09-01

    The complication of Fanconi anemia (FA) with acute leukemia is rare and challenging to treat because of high relapse rates, despite the improved outcome of hematopoietic stem cell transplantation with fludarabine-based conditioning for treating FA patients with hematological abnormalities. We added high-dose cytarabine to fludarabine-based conditioning to promote an enhanced antitumor effect and successfully subjected 4 patients with FA, including 3 with acute leukemia, to hematopoietic stem cell transplantation. All patients remain alive without treatment-related mortality or evidence of disease. Adding high-dose cytarabine to fludarabine-based conditioning may be tolerable and effective for treating FA patients with acute leukemia. PMID:27246371

  11. MiR-24 Promotes the Survival of Hematopoietic Cells

    PubMed Central

    Nguyen, Tan; Rich, Audrey; Dahl, Richard

    2013-01-01

    The microRNA, miR-24, inhibits B cell development and promotes myeloid development of hematopoietic progenitors. Differential regulation of cell survival in myeloid and lymphoid cells by miR-24 may explain how miR-24′s affects hematopoietic progenitors. MiR-24 is reported to regulate apoptosis, either positively or negatively depending on cell context. However, no role for miR-24 in regulating cell death has been previously described in blood cells. To examine miR-24′s effect on survival, we expressed miR-24 via retrovirus in hematopoietic cells and induced cell death with cytokine or serum withdrawal. We observed that miR-24 enhanced survival of myeloid and B cell lines as well as primary hematopoietic cells. Additionally, antagonizing miR-24 with shRNA in hematopoietic cells made them more sensitive to apoptotic stimuli, suggesting miR-24 functions normally to promote blood cell survival. Since we did not observe preferential protection of myeloid over B cells, miR-24′s pro-survival effect does not explain its promotion of myelopoiesis. Moreover, expression of pro-survival protein, Bcl-xL, did not mimic miR-24′s impact on cellular differentiation, further supporting this conclusion. Our results indicate that miR-24 is a critical regulator of hematopoietic cell survival. This observation has implications for leukemogenesis. Several miRNAs that regulate apoptosis have been shown to function as either tumor suppressors or oncogenes during leukemogenesis. MiR-24 is expressed highly in primary acute myelogenous leukemia, suggesting that its pro-survival activity could contribute to the transformation of hematopoietic cells. PMID:23383180

  12. Overexpression of CEBPA resulting from the translocation t(14;19)(q32;q13) of human precursor B acute lymphoblastic leukemia.

    PubMed

    Chapiro, Elise; Russell, Lisa; Radford-Weiss, Isabelle; Bastard, Christian; Lessard, Michel; Struski, Stephanie; Cave, Helene; Fert-Ferrer, Sandra; Barin, Carole; Maarek, Odile; Della-Valle, Veronique; Strefford, Jonathan C; Berger, Roland; Harrison, Christine J; Bernard, Olivier A; Nguyen-Khac, Florence

    2006-11-15

    Subtle variation in the expression or function of a small group of transcription factors can drive leukemogenesis. The CEBPA protein is known to regulate the balance between cell proliferation and differentiation during early hematopoietic development and myeloid differentiation. In human myeloid leukemia, CEBPA is frequently inactivated by mutation and indirect and posttranslational mechanisms, in keeping with tumor suppressor properties. We report that CEBPA is activated by juxtaposition to the immunoglobulin gene enhancer upon its rearrangement with the immunoglobulin heavy-chain locus in precursor B-cell acute lymphoblastic leukemia harboring t(14;19)(q32;q13). Overexpression of apparently normal CEBPA RNA or protein was observed in 6 patients. These data indicate that CEBPA may exhibit oncogenic as well as tumor suppressor properties in human leukemogenesis. PMID:16873674

  13. Hematopoietic stem/progenitor cell commitment to the megakaryocyte lineage.

    PubMed

    Woolthuis, Carolien M; Park, Christopher Y

    2016-03-10

    The classical model of hematopoiesis has long held that hematopoietic stem cells (HSCs) sit at the apex of a developmental hierarchy in which HSCs undergo long-term self-renewal while giving rise to cells of all the blood lineages. In this model, self-renewing HSCs progressively lose the capacity for self-renewal as they transit into short-term self-renewing and multipotent progenitor states, with the first major lineage commitment occurring in multipotent progenitors, thus giving rise to progenitors that initiate the myeloid and lymphoid branches of hematopoiesis. Subsequently, within the myeloid lineage, bipotent megakaryocyte-erythrocyte and granulocyte-macrophage progenitors give rise to unipotent progenitors that ultimately give rise to all mature progeny. However, over the past several years, this developmental scheme has been challenged, with the origin of megakaryocyte precursors being one of the most debated subjects. Recent studies have suggested that megakaryocytes can be generated from multiple pathways and that some differentiation pathways do not require transit through a requisite multipotent or bipotent megakaryocyte-erythrocyte progenitor stage. Indeed, some investigators have argued that HSCs contain a subset of cells with biased megakaryocyte potential, with megakaryocytes directly arising from HSCs under steady-state and stress conditions. In this review, we discuss the evidence supporting these nonclassical megakaryocytic differentiation pathways and consider their relative strengths and weaknesses as well as the technical limitations and potential pitfalls in interpreting these studies. Ultimately, such pitfalls will need to be overcome to provide a comprehensive and definitive understanding of megakaryopoiesis. PMID:26787736

  14. Fludarabine Phosphate, Busulfan, and Anti-Thymocyte Globulin Followed By Donor Peripheral Blood Stem Cell Transplant, Tacrolimus, and Methotrexate in Treating Patients With Myeloid Malignancies

    ClinicalTrials.gov

    2016-05-04

    Accelerated Phase Chronic Myelogenous Leukemia; Adult Acute Myeloid Leukemia in Remission; Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Blastic Phase Chronic Myelogenous Leukemia; Childhood Acute Myeloid Leukemia in Remission; Childhood Chronic Myelogenous Leukemia; Childhood Myelodysplastic Syndromes; Chronic Phase Chronic Myelogenous Leukemia; de Novo Myelodysplastic Syndromes; Hematopoietic/Lymphoid Cancer; Myelodysplastic/Myeloproliferative Neoplasm, Unclassifiable; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Myeloid Leukemia; Recurrent Childhood Acute Myeloid Leukemia; Relapsing Chronic Myelogenous Leukemia

  15. Inhibition of B Lymphopoiesis by Adipocytes and IL-1-Producing Myeloid-Derived Suppressor Cells.

    PubMed

    Kennedy, Domenick E; Knight, Katherine L

    2015-09-15

    B lymphopoiesis declines with age, and this decline correlates with increased adipose tissue in the bone marrow (BM). Also, adipocyte-derived factors are known to inhibit B lymphopoiesis. Using cocultures of mouse BM cells with OP9 stromal cells, we found that adipocyte-conditioned medium induces the generation of CD11b(+)Gr1(+) myeloid cells, which inhibit B cell development in vitro. Adipocyte-conditioned medium-induced CD11b(+)Gr1(+) cells express Arg1 (arginase) and Nos2 (inducible NO synthase) and suppress CD4(+) T cell proliferation, indicating that these cells are myeloid-derived suppressor cells (MDSCs). Blocking arginase and inducible NO synthase did not restore B lymphopoiesis, indicating that inhibition is not mediated by these molecules. Transwell and conditioned-medium experiments showed that MDSCs inhibit B lymphopoiesis via soluble factors, and by cytokine array we identified IL-1 as an important factor. Addition of anti-IL-1 Abs restored B lymphopoiesis in BM cultures containing MDSCs, showing that MDSC inhibition of B lymphopoiesis is mediated by IL-1. By treating hematopoietic precursors with IL-1, we found that multipotent progenitors are targets of IL-1. This study uncovers a novel function for MDSCs to inhibit B lymphopoiesis through IL-1. We suggest that inflammaging contributes to a decline of B lymphopoiesis in aged individuals, and furthermore, that MDSCs and IL-1 provide therapeutic targets for restoration of B lymphopoiesis in aged and obese individuals. PMID:26268654

  16. Myeloid Cell Nuclear Differentiation Antigen (MNDA) Expression Distinguishes Extramedullary Presentations of Myeloid Leukemia From Blastic Plasmacytoid Dendritic Cell Neoplasm.

    PubMed

    Johnson, Ryan C; Kim, Jinah; Natkunam, Yasodha; Sundram, Uma; Freud, Aharon G; Gammon, Bryan; Cascio, Michael J

    2016-04-01

    Myeloid neoplasms constitute one of the most common malignancies in adults. In most cases these proliferations initially manifest in the blood and marrow; however, extramedullary involvement may precede blood or marrow involvement in a subset of cases, making a definitive diagnosis challenging by morphologic and immunohistochemical assessment alone. Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare, aggressive entity that frequently presents in extramedullary sites and can show morphologic and immunophenotypic overlap with myeloid neoplasms. Given that BPDCN and myeloid neoplasms may both initially present in extramedullary sites and that novel targeted therapies may be developed that exploit the unique molecular signature of BPDCN, new immunophenotypic markers that can reliably separate myeloid neoplasms from BPDCN are desirable. We evaluated the utility of myeloid cell nuclear differentiation antigen (MNDA) expression in a series of extramedullary myeloid leukemias (EMLs) and BPDCN. Forty biopsies containing EML and 19 biopsies containing BPDCN were studied by MNDA immunohistochemistry. The majority of myeloid neoplasms showed nuclear expression of MNDA (65%). In contrast, all cases of BPDCN lacked MNDA expression. These findings show that MNDA is expressed in the majority of EMLs and support the inclusion of MNDA immunohistochemistry in the diagnostic evaluation of blastic hematopoietic infiltrates, particularly when the differential diagnosis is between myeloid leukemia and BPDCN. PMID:26796502

  17. Myocardial infarction activates CCR2+ hematopoietic stem and progenitor cells

    PubMed Central

    Dutta, Partha; Sager, Hendrik B.; Stengel, Kristy R.; Naxerova, Kamila; Courties, Gabriel; Saez, Borja; Silberstein, Lev; Heidt, Timo; Sebas, Matthew; Sun, Yuan; Wojtkiewicz, Gregory; Feruglio, Paolo Fumene; King, Kevin; Baker, Joshua N.; van der Laan, Anja M.; Borodovsky, Anna; Fitzgerald, Kevin; Hulsmans, Maarten; Hoyer, Friedrich; Iwamoto, Yoshiko; Vinegoni, Claudio; Brown, Dennis; Di Carli, Marcelo; Libby, Peter; Hiebert, Scott; Scadden, David; Swirski, Filip K.; Weissleder, Ralph; Nahrendorf, Matthias

    2015-01-01

    SUMMARY Following myocardial infarction (MI), myeloid cells derived from the hematopoietic system drive a sharp increase in systemic leukocyte levels that correlate closely with mortality. The origin of these myeloid cells, and the response of hematopoietic stem and progenitor cells (HSPCs) to MI, however, is unclear. Here, we identify a CCR2+CD150+CD48− LSK hematopoietic subset as the most upstream contributor to emergency myelopoiesis after ischemic organ injury. CCR2+ HSPC have fourfold higher proliferation rates than CCR2−CD150+CD48− LSK cells, display a myeloid differentiation bias, and dominate the migratory HSPC population. We further demonstrate the myeloid translocation gene 16 (Mtg16) regulates CCR2+ HSPC emergence. Mtg16−/− mice have decreased levels of systemic monocytes and infarct-associated macrophages and display compromised tissue healing and post-MI heart failure. Together, these data provide insights into regulation of emergency hematopoiesis after ischemic injury, and identify potential therapeutic targets to modulate leukocyte output after MI. PMID:25957903

  18. The homeodomain transcription factor Prep1 (pKnox1) is required for hematopoietic stem and progenitor cell activity.

    PubMed

    Di Rosa, Patrizia; Villaescusa, J Carlos; Longobardi, Elena; Iotti, Giorgio; Ferretti, Elisabetta; Diaz, Victor M; Miccio, Annarita; Ferrari, Giuliana; Blasi, Francesco

    2007-11-15

    Most of the hypomorphic Prep1(i/i) embryos (expressing 3-10% of the Prep1 protein), die between E17.5 and P0, with profound anemia, eye malformations and angiogenic anomalies [Ferretti, E., Villaescusa, J.C., Di Rosa, P., Fernandez-Diaz, L.-C., Longobardi, E., Mazzieri, R., Miccio, A., Micali, N., Selleri, L., Ferrari G., Blasi, F. (2006). Hypomorphic mutation of the TALE gene Prep1 (pKnox1) causes a major reduction of Pbx and Meis proteins and a pleiotropic embryonic phenotype. Mol. Cell. Biol. 26, 5650-5662]. We now report on the hematopoietic phenotype of these embryos. Prep1(i/i) fetal livers (FL) are hypoplastic, produce less common myeloid progenitors colonies (CFU-GEMM) in cytokine-supplemented methylcellulose and have an increased number of B-cells precursors that differentiate poorly. Prep1(i/i) FL is able to protect lethally irradiated mice only at high cell doses but the few protected mice show major anomalies in all hematopoietic lineages in both bone marrow (BM) and peripheral organs. Prep1(i/i) FL cells compete inefficiently with wild type bone marrow in competitive repopulation experiments, suggesting that the major defect lies in long-term repopulating hematopoietic stem cells (LTR-HSC). Indeed, wt embryonic expression of Prep1 in the aorta-gonad-mesonephros (AGM) region, fetal liver (FL), cKit(+)Sca1(+)Lin(-)AA4.1(+) (KSLA) cells and B-lymphocytes precursors agrees with the observed phenotype. We therefore conclude that Prep1 is required for a correct and complete hematopoiesis. PMID:17904118

  19. SWEF Proteins Distinctly Control Maintenance and Differentiation of Hematopoietic Stem Cells

    PubMed Central

    Ripich, Tatsiana; Chacón-Martínez, Carlos Andrés; Fischer, Luise; Pernis, Alessandra; Kiessling, Nadine; Garbe, Annette I.; Jessberger, Rolf

    2016-01-01

    SWAP-70 and DEF6, two proteins that feature similar domain and motif arrangements, are mainly known for their functions in differentiated hematopoietic cells. Both proteins interact with and regulate RhoGTPases and F-actin dynamics, yet their role in hematopoietic stem and precursor cells (HSPCs) remained unexplored. Here, the role of the SWEF proteins SWAP-70 and DEF6 in HSPCs was examined. Both SWEF proteins are expressed in HSCs. HSCs and different precursor populations were analyzed in mice deficient for SWAP-70, DEF6, SWAP-70 and DEF6 (double knockout, DKO), and wild-type controls. HSPCs isolated from these strains were used for competitive adoptive transfer into irradiated wild-type mice. Reconstitution of the myeloid and lymphoid lineages in the recipient mice was determined. The numbers of HSPCs in the bone marrow of Swap-70-/- and Swap-70-/-Def6-/- mice were >3-fold increased. When transplanted into lethally irradiated wild-type recipients, the reconstitution potential of Swap-70-/- HSPCs was intrinsically impaired in competing with wild-type HSPCs for contribution to hematopoiesis. Def6-/- HSPCs show wild type-like reconstitution potential under the same transplantation conditions. DKO HSPCs reconstituted to only 25% of wild-type levels, indicating a partial rescue by DEF6 deficiency in the Swap-70-/- background. Our study reveals the two SWEF proteins as important contributors to HSPC biology. Despite their similarity these two proteins regulate HSC/progenitor homeostasis, self-renewal, lineage contributions and repopulation in a distinct and mostly antagonistic manner. PMID:27561029

  20. SWEF Proteins Distinctly Control Maintenance and Differentiation of Hematopoietic Stem Cells.

    PubMed

    Ripich, Tatsiana; Chacón-Martínez, Carlos Andrés; Fischer, Luise; Pernis, Alessandra; Kiessling, Nadine; Garbe, Annette I; Jessberger, Rolf

    2016-01-01

    SWAP-70 and DEF6, two proteins that feature similar domain and motif arrangements, are mainly known for their functions in differentiated hematopoietic cells. Both proteins interact with and regulate RhoGTPases and F-actin dynamics, yet their role in hematopoietic stem and precursor cells (HSPCs) remained unexplored. Here, the role of the SWEF proteins SWAP-70 and DEF6 in HSPCs was examined. Both SWEF proteins are expressed in HSCs. HSCs and different precursor populations were analyzed in mice deficient for SWAP-70, DEF6, SWAP-70 and DEF6 (double knockout, DKO), and wild-type controls. HSPCs isolated from these strains were used for competitive adoptive transfer into irradiated wild-type mice. Reconstitution of the myeloid and lymphoid lineages in the recipient mice was determined. The numbers of HSPCs in the bone marrow of Swap-70-/- and Swap-70-/-Def6-/- mice were >3-fold increased. When transplanted into lethally irradiated wild-type recipients, the reconstitution potential of Swap-70-/- HSPCs was intrinsically impaired in competing with wild-type HSPCs for contribution to hematopoiesis. Def6-/- HSPCs show wild type-like reconstitution potential under the same transplantation conditions. DKO HSPCs reconstituted to only 25% of wild-type levels, indicating a partial rescue by DEF6 deficiency in the Swap-70-/- background. Our study reveals the two SWEF proteins as important contributors to HSPC biology. Despite their similarity these two proteins regulate HSC/progenitor homeostasis, self-renewal, lineage contributions and repopulation in a distinct and mostly antagonistic manner. PMID:27561029

  1. Targeting the Microenvironment in Acute Myeloid Leukemia

    PubMed Central

    Rashidi, Armin; Uy, Geoffrey L.

    2015-01-01

    The bone marrow microenvironment plays a critical role in the development, progression, and relapse of acute myeloid leukemia (AML). Similar to normal hematopoietic stem cells, AML blasts express receptors on their surface, allowing them to interact with specific components of the marrow microenvironment. These interactions contribute to both chemotherapy resistance and disease relapse. Preclinical studies and early phase clinical trials have demonstrated the potential for targeting the tumor-microenvironment interactions in AML. Agents currently under investigation include hypoxia-inducible agents and inhibitors of CXCR4 and adhesion molecules such as VLA-4 and E-selectin. PMID:25921388

  2. Murine Hematopoietic Stem cells and Progenitors Express Adrenergic Receptors

    PubMed Central

    Muthu, Kuzhali; Iyer, Sivaraman; He, L-K.; Szilagyi, Andrea; Gamelli, Richard L; Shankar, Ravi; Jones, Stephen B

    2007-01-01

    Association between the nervous and immune system is well documented. Immune cells originate within the bone marrow that is innervated. Thermal injury induces adrenergic stimulation, augments monocytopoiesis and alters the β-adrenergic receptor (AR) profile of bone marrow monocyte committed progenitors. This provides an impetus to study AR expression in hematopoietic progenitors along myeloid lineage. Using FACS analysis and confocal microscopy, we report the expression of α1-, α2- and β2- AR in enriched populations of ER-MP20+ and ER-MP12+ myeloid progenitors, CD117+ and CD34+ multi-potential progenitors and more importantly pluripotent stem cells suggesting a plausible role for catecholamine in hematopoietic development. PMID:17428548

  3. ESAM is a novel human hematopoietic stem cell marker associated with a subset of human leukemias.

    PubMed

    Ishibashi, Tomohiko; Yokota, Takafumi; Tanaka, Hirokazu; Ichii, Michiko; Sudo, Takao; Satoh, Yusuke; Doi, Yukiko; Ueda, Tomoaki; Tanimura, Akira; Hamanaka, Yuri; Ezoe, Sachiko; Shibayama, Hirohiko; Oritani, Kenji; Kanakura, Yuzuru

    2016-04-01

    Reliable markers are essential to increase our understanding of the biological features of human hematopoietic stem cells and to facilitate the application of hematopoietic stem cells in the field of transplantation and regenerative medicine. We previously identified endothelial cell-selective adhesion molecule (ESAM) as a novel functional marker of hematopoietic stem cells in mice. Here, we found that ESAM can also be used to purify human hematopoietic stem cells from all the currently available sources (adult bone marrow, mobilized peripheral blood, and cord blood). Multipotent colony-forming units and long-term hematopoietic-reconstituting cells in immunodeficient mice were found exclusively in the ESAM(High) fraction of CD34(+)CD38(-) cells. The CD34(+)CD38(-) fraction of cord blood and collagenase-treated bone marrow contained cells exhibiting extremely high expression of ESAM; these cells are likely to be related to the endothelial lineage. Leukemia cell lines of erythroid and megakaryocyte origin, but not those of myeloid or lymphoid descent, were ESAM positive. However, high ESAM expression was observed in some primary acute myeloid leukemia cells. Furthermore, KG-1a myeloid leukemia cells switched from ESAM negative to ESAM positive with repeated leukemia reconstitution in vivo. Thus, ESAM is a useful marker for studying both human hematopoietic stem cells and leukemia cells. PMID:26774386

  4. MicroRNA-486-5p is an erythroid oncomiR of the myeloid leukemias of Down syndrome

    PubMed Central

    Shaham, Lital; Vendramini, Elena; Ge, Yubin; Goren, Yaron; Birger, Yehudit; Tijssen, Marloes R.; McNulty, Maureen; Geron, Ifat; Schwartzman, Omer; Goldberg, Liat; Chou, Stella T.; Pitman, Holly; Weiss, Mitchell J.; Michaeli, Shulamit; Sredni, Benjamin; Göttgens, Berthold; Crispino, John D.; Taub, Jeffrey W.

    2015-01-01

    Children with Down syndrome (DS) are at increased risk for acute myeloid leukemias (ML-DS) characterized by mixed megakaryocytic and erythroid phenotype and by acquired mutations in the GATA1 gene resulting in a short GATA1s isoform. The chromosome 21 microRNA (miR)-125b cluster has been previously shown to cooperate with GATA1s in transformation of fetal hematopoietic progenitors. In this study, we report that the expression of miR-486-5p is increased in ML-DS compared with non-DS acute megakaryocytic leukemias (AMKLs). miR-486-5p is regulated by GATA1 and GATA1s that bind to the promoter of its host gene ANK1. miR-486-5p is highly expressed in mouse erythroid precursors and knockdown (KD) in ML-DS cells reduced their erythroid phenotype. Ectopic expression and KD of miR-486-5p in primary fetal liver hematopoietic progenitors demonstrated that miR-486-5p cooperates with Gata1s to enhance their self renewal. Consistent with its activation of AKT, overexpression and KD experiments showed its importance for growth and survival of human leukemic cells. Thus, miR-486-5p cooperates with GATA1s in supporting the growth and survival, and the aberrant erythroid phenotype of the megakaryocytic leukemias of DS. PMID:25533034

  5. MicroRNA-486-5p is an erythroid oncomiR of the myeloid leukemias of Down syndrome.

    PubMed

    Shaham, Lital; Vendramini, Elena; Ge, Yubin; Goren, Yaron; Birger, Yehudit; Tijssen, Marloes R; McNulty, Maureen; Geron, Ifat; Schwartzman, Omer; Goldberg, Liat; Chou, Stella T; Pitman, Holly; Weiss, Mitchell J; Michaeli, Shulamit; Sredni, Benjamin; Göttgens, Berthold; Crispino, John D; Taub, Jeffrey W; Izraeli, Shai

    2015-02-19

    Children with Down syndrome (DS) are at increased risk for acute myeloid leukemias (ML-DS) characterized by mixed megakaryocytic and erythroid phenotype and by acquired mutations in the GATA1 gene resulting in a short GATA1s isoform. The chromosome 21 microRNA (miR)-125b cluster has been previously shown to cooperate with GATA1s in transformation of fetal hematopoietic progenitors. In this study, we report that the expression of miR-486-5p is increased in ML-DS compared with non-DS acute megakaryocytic leukemias (AMKLs). miR-486-5p is regulated by GATA1 and GATA1s that bind to the promoter of its host gene ANK1. miR-486-5p is highly expressed in mouse erythroid precursors and knockdown (KD) in ML-DS cells reduced their erythroid phenotype. Ectopic expression and KD of miR-486-5p in primary fetal liver hematopoietic progenitors demonstrated that miR-486-5p cooperates with Gata1s to enhance their self renewal. Consistent with its activation of AKT, overexpression and KD experiments showed its importance for growth and survival of human leukemic cells. Thus, miR-486-5p cooperates with GATA1s in supporting the growth and survival, and the aberrant erythroid phenotype of the megakaryocytic leukemias of DS. PMID:25533034

  6. CD13 is dispensable for normal hematopoiesis and myeloid cell functions in the mouse

    PubMed Central

    Winnicka, Beata; O'Conor, Catherine; Schacke, Wolfgang; Vernier, Kaitlyn; Grant, Christina L.; Fenteany, Fiona Hall; Pereira, Flavia E.; Liang, Brannen; Kaur, Anupinder; Zhao, Ran; Montrose, David C.; Rosenberg, Daniel W.; Aguila, Hector L.; Shapiro, Linda H.

    2010-01-01

    The robust and consistent expression of the CD13 cell surface marker on very early as well as differentiated myeloid hematopoietic cells has prompted numerous investigations seeking to define roles for CD13 in myeloid cells. To address the function of myeloid CD13 directly, we created a CD13 null mouse and assessed the responses of purified primary macrophages or DCs from WT and CD13 null animals in cell assays and inflammatory disease models, where CD13 has been implicated previously. We find that mice lacking CD13 develop normally with normal hematopoietic profiles except for an increase in thymic but not peripheral T cell numbers. Moreover, in in vitro assays, CD13 appears to be largely dispensable for the aspects of phagocytosis, proliferation, and antigen presentation that we tested, although we observed a slight decrease in actin-independent erythrocyte uptake. However, in agreement with our published studies, we show that lack of monocytic CD13 completely ablates anti-CD13-dependent monocyte adhesion to WT endothelial cells. In vivo assessment of four inflammatory disease models showed that lack of CD13 has little effect on disease onset or progression. Nominal alterations in gene expression levels between CD13 WT and null macrophages argue against compensatory mechanisms. Therefore, although CD13 is highly expressed on myeloid cells and is a reliable marker of the myeloid lineage of normal and leukemic cells, it is not a critical regulator of hematopoietic development, hemostasis, or myeloid cell function. PMID:20430777

  7. Epigenetic Regulation of Hematopoietic Stem Cells

    PubMed Central

    Sharma, Shilpa; Gurudutta, Gangenahalli

    2016-01-01

    Hematopoietic stem cells are endowed with a distinct potential to bolster self-renewal and to generate progeny that differentiate into mature cells of myeloid and lymphoid lineages. Both hematopoietic stem cells and mature cells have the same genome, but their gene expression is controlled by an additional layer of epigenetics such as DNA methylation and post-translational histone modifications, enabling each cell-type to acquire various forms and functions. Until recently, several studies have largely focussed on the transcription factors andniche factors for the understanding of the molecular mechanisms by which hematopoietic cells replicate and differentiate. Several lines of emerging evidence suggest that epigenetic modifications eventually result in a defined chromatin structure and an “individual” gene expression pattern, which play an essential role in the regulation of hematopoietic stem cell self-renewal and differentiation. Distinct epigenetic marks decide which sets of genes may be expressed and which genes are kept silent. Epigenetic mechanisms are interdependent and ensure lifelong production of blood and bone marrow, thereby contributing to stem cell homeostasis. The epigenetic analysis of hematopoiesis raises the exciting possibility that chromatin structure is dynamic enough for regulated expression of genes. Though controlled chromatin accessibility plays an essential role in maintaining blood homeostasis; mutations in chromatin impacts on the regulation of genes critical to the development of leukemia. In this review, we explored the contribution of epigenetic machinery which has implications for the ramification of molecular details of hematopoietic self-renewal for normal development and underlying events that potentially co-operate to induce leukemia. PMID:27426084

  8. Maxillo-ethmoidal chloroma in acute myeloid leukaemia: Case report

    PubMed Central

    Ferri, E; Minotto, C; Ianniello, F; Cavaleri, S; Armato, E; Capuzzo, P

    2005-01-01

    Summary Chloroma, also called Granulocytic Sarcoma or Myeloid Sarcoma, is a rare malignant extra-medullary neoplasm of myeloid precursor cells. It is usually associated with myeloproliferative disorders but its appearance may precede the onset of leukaemia. Chloroma may be found in several extracranial sites. Involvement of the head and neck region is uncommon. Differential diagnosis is often difficult and includes acute lymphoblastic leukaemia, large cell NHL, lymphoblastic lymphoma and Ewing’s sarcoma. The case is presented of a maxillo-ethmoidal chloroma occurring in a case of poor prognosis acute myeloid leukaemia, emphasizing the clinical and cyto-histological features and problems concerning differential diagnosis. PMID:16450777

  9. Proinflammatory signaling regulates hematopoietic stem cell emergence.

    PubMed

    Espín-Palazón, Raquel; Stachura, David L; Campbell, Clyde A; García-Moreno, Diana; Del Cid, Natasha; Kim, Albert D; Candel, Sergio; Meseguer, José; Mulero, Victoriano; Traver, David

    2014-11-20

    Hematopoietic stem cells (HSCs) underlie the production of blood and immune cells for the lifetime of an organism. In vertebrate embryos, HSCs arise from the unique transdifferentiation of hemogenic endothelium comprising the floor of the dorsal aorta during a brief developmental window. To date, this process has not been replicated in vitro from pluripotent precursors, partly because the full complement of required signaling inputs remains to be determined. Here, we show that TNFR2 via TNF? activates the Notch and NF-?B signaling pathways to establish HSC fate, indicating a requirement for inflammatory signaling in HSC generation. We determine that primitive neutrophils are the major source of TNF?, assigning a role for transient innate immune cells in establishing the HSC program. These results demonstrate that proinflammatory signaling, in the absence of infection, is utilized by the developing embryo to generate the lineal precursors of the adult hematopoietic system. PMID:25416946

  10. Proinflammatory signaling regulates hematopoietic stem cell emergence

    PubMed Central

    Espín-Palazón, Raquel; Stachura, David L.; Campbell, Clyde A.; García-Moreno, Diana; Cid, Natasha Del; Kim, Albert D.; Candel, Sergio; Meseguer, José; Mulero, Victoriano; Traver, David

    2014-01-01

    Summary Hematopoietic stem cells (HSCs) underlie the production of blood and immune cells for the lifetime of an organism. In vertebrate embryos, HSCs arise from the unique transdifferentiation of hemogenic endothelium comprising the floor of the dorsal aorta during a brief developmental window. To date, this process has not been replicated in vitro from pluripotent precursors, partly because the full complement of required signaling inputs remains to be determined. Here, we show that TNFR2 via TNFα activates the Notch and NF-κB signaling pathways to establish HSC fate, indicating a requirement for inflammatory signaling in HSC generation. We determine that primitive neutrophils are the major source of TNFα, assigning a role for transient innate immune cells in establishing the HSC program. These results demonstrate that proinflammatory signaling, in the absence of infection, is utilized by the developing embryo to generate the lineal precursors of the adult hematopoietic system. PMID:25416946

  11. Differentiation Therapy of Acute Myeloid Leukemia

    PubMed Central

    Gocek, Elzbieta; Marcinkowska, Ewa

    2011-01-01

    Acute Myeloid Leukemia (AML) is a predominant acute leukemia among adults, characterized by accumulation of malignantly transformed immature myeloid precursors. A very attractive way to treat myeloid leukemia, which is now called ‘differentiation therapy’, was proposed as in vitro studies have shown that a variety of agents stimulate differentiation of the cell lines isolated from leukemic patients. One of the differentiation-inducing agents, all-trans retinoic acid (ATRA), which can induce granulocytic differentiation in myeloid leukemic cell lines, has been introduced into clinics to treat patients with acute promyelocytic leukemia (APL) in which a PML-RARA fusion protein is generated by a t(15;17)(q22;q12) chromosomal translocation. Because differentiation therapy using ATRA has significantly improved prognosis for patients with APL, many efforts have been made to find alternative differentiating agents. Since 1,25-dihydroxyvitamin D3 (1,25D) is capable of inducing in vitro monocyte/macrophage differentiation of myeloid leukemic cells, clinical trials have been performed to estimate its potential to treat patients with AML or myelodysplastic syndrome (MDS). Unfortunately therapeutic concentrations of 1,25D can induce potentially fatal systemic hypercalcemia, thus limiting clinical utility of that compound. Attempts to overcome this problem have focused on the synthesis of 1,25D analogs (VDAs) which retain differentiation inducing potential, but lack its hypercalcemic effects. This review aims to discuss current problems and potential solutions in differentiation therapy of AML. PMID:24212816

  12. [Recent Advances of Research on CEBPA Mutation in Acute Myeloid Leukemia].

    PubMed

    Yu, Wen-Qing; Sun, Jing-Nan; Tan, Ye-Hui; Cui, Jiu-Wei; Li, Wei

    2015-12-01

    CCAAT/enhancer binding protein alpha gene (CEBPA) is an important transcription factor in maintenance of differentiation of granulocyte series of hematopoietic system. It plays a key role in regulating cell proliferation and differentiation. CEBPA mutation easily occurs in M1 and M2 type of acute myeloid leukemia, about 5%-14% in adult acute myeloid leukemia and 7.9% in children with acute myeloid leukemia. At present, domestic CEBPA mutation research is far less than abroad. This review focuses on the structual characteristics and detection method of CEBPA, CEBPA clinical features, the effect of CEBPA mutation on the prognosis of patients and the choice of treatment. PMID:26708912

  13. Context-dependent regulation of hematopoietic lineage choice by HEBAlt.

    PubMed

    Wang, Duncheng; Claus, Carol L; Rajkumar, Paula; Braunstein, Marsela; Moore, Amanda J; Sigvardsson, Mikael; Anderson, Michele K

    2010-10-01

    Hematopoietic development is controlled by combinatorial interactions between E-protein transcription factors and other lineage regulators that operate in the context of gene-regulatory networks. The E-proteins HEB and E2A are critical for T cell and B cell development, but the mechanisms by which their activities are directed to different genes in each lineage are unclear. We found that a short form of HEB, HEBAlt, acts downstream of Delta-like (DL)-Notch signaling to promote T cell development. In this paper, we show that forced expression of HEBAlt in mouse hematopoietic progenitors inhibited B cell development, but it allowed them to adopt a myeloid fate. HEBAlt interfered with the activity of E2A homodimers and with the expression of the transcription factor Pax5, both of which are critical for B cell development. However, when combined with DL-Notch signaling, HEBAlt enhanced the generation of T cell progenitors at the expense of myeloid cells. The longer form of HEB, HEBCan, also inhibited E47 activity and Pax5 expression, but it did not collaborate with DL-Notch signaling to suppress myeloid potential. Therefore, HEBAlt can suppress B cell or myeloid potential in a context-specific manner, which suggests a role for this factor in maintaining T lineage priming prior to commitment. PMID:20826759

  14. The molecular basis of myeloid malignancies

    PubMed Central

    KITAMURA, Toshio; INOUE, Daichi; OKOCHI-WATANABE, Naoko; KATO, Naoko; KOMENO, Yukiko; LU, Yang; ENOMOTO, Yutaka; DOKI, Noriko; UCHIDA, Tomoyuki; KAGIYAMA, Yuki; TOGAMI, Katsuhiro; KAWABATA, Kimihito C.; NAGASE, Reina; HORIKAWA, Sayuri; HAYASHI, Yasutaka; SAIKA, Makoto; FUKUYAMA, Tomofusa; IZAWA, Kumi; OKI, Toshihiko; NAKAHARA, Fumio; KITAURA, Jiro

    2014-01-01

    Myeloid malignancies consist of acute myeloid leukemia (AML), myelodysplastic syndromes (MDS) and myeloproliferative neoplasm (MPN). The latter two diseases have preleukemic features and frequently evolve to AML. As with solid tumors, multiple mutations are required for leukemogenesis. A decade ago, these gene alterations were subdivided into two categories: class I mutations stimulating cell growth or inhibiting apoptosis; and class II mutations that hamper differentiation of hematopoietic cells. In mouse models, class I mutations such as the Bcr-Abl fusion kinase induce MPN by themselves and some class II mutations such as Runx1 mutations induce MDS. Combinations of class I and class II mutations induce AML in a variety of mouse models. Thus, it was postulated that hematopoietic cells whose differentiation is blocked by class II mutations would autonomously proliferate with class I mutations leading to the development of leukemia. Recent progress in high-speed sequencing has enabled efficient identification of novel mutations in a variety of molecules including epigenetic factors, splicing factors, signaling molecules and proteins in the cohesin complex; most of these are not categorized as either class I or class II mutations. The functional consequences of these mutations are now being extensively investigated. In this article, we will review the molecular basis of hematological malignancies, focusing on mouse models and the interfaces between these models and clinical findings, and revisit the classical class I/II hypothesis. PMID:25504228

  15. Biology of hematopoietic stem cells and progenitors: implications for clinical application.

    PubMed

    Kondo, Motonari; Wagers, Amy J; Manz, Markus G; Prohaska, Susan S; Scherer, David C; Beilhack, Georg F; Shizuru, Judith A; Weissman, Irving L

    2003-01-01

    Stem cell biology is scientifically, clinically, and politically a current topic. The hematopoietic stem cell, the common ancestor of all types of blood cells, is one of the best-characterized stem cells in the body and the only stem cell that is clinically applied in the treatment of diseases such as breast cancer, leukemias, and congenital immunodeficiencies. Multicolor cell sorting enables the purification not only of hematopoietic stem cells, but also of their downstream progenitors such as common lymphoid progenitors and common myeloid progenitors. Recent genetic approaches including gene chip technology have been used to elucidate the gene expression profile of hematopoietic stem cells and other progenitors. Although the mechanisms that control self-renewal and lineage commitment of hematopoietic stem cells are still ambiguous, recent rapid advances in understanding the biological nature of hematopoietic stem and progenitor cells have broadened the potential application of these cells in the treatment of diseases. PMID:12615892

  16. Tumor suppressor genes in myeloid differentiation and leukemogenesis.

    PubMed

    Britschgi, Christian; Fey, Martin F

    2009-03-01

    Tumor suppressor genes, such as p53, RB, the INK4-ARF family and PML, suppress malignant transformation by regulating cell cycle progression, ensuring the fidelity of DNA replication and chromosomal segregation, or by inducing apoptosis in response to potentially deleterious events. In myeloid leukemia, hematopoietic differentiation resulting from highly coordinated, stage-wise expression of myeloid transcription and soluble signaling factors is disrupted leading to a block in terminal differentiation and uncontrolled proliferation. This virtually always involves functional inactivation or genetic disruption of one or several tumor suppressor genes in order to circumvent their checkpoint control and apoptosis-inducing functions. Hence, reactivation of tumor suppressor gene function has therapeutic potential and can possibly enhance conventional cytotoxic chemotherapy. In this review, we focus on the role of different tumor suppressor genes in myeloid differentiation and leukemogenesis, and discuss implications for therapy. PMID:19284382

  17. Lineage-instructive function of C/EBPα in multipotent hematopoietic cells and early thymic progenitors.

    PubMed

    Wölfler, Albert; Danen-van Oorschot, Astrid A; Haanstra, Jurgen R; Valkhof, Marijke; Bodner, Claudia; Vroegindeweij, Eric; van Strien, Paulette; Novak, Alexandra; Cupedo, Tom; Touw, Ivo P

    2010-11-18

    Hematopoiesis is tightly controlled by transcription regulatory networks, but how and when specific transcription factors control lineage commitment are still largely unknown. Within the hematopoietic stem cell (Lin(-)Sca-1(+)c-Kit(+)) compartment these lineage-specific transcription factors are expressed at low levels but are up-regulated with the process of lineage specification. CCAAT/enhancer binding protein α (C/EBPα) represents one of these factors and is involved in myeloid development and indispensable for formation of granulocytes. To track the cellular fate of stem and progenitor cells, which express C/EBPα, we developed a mouse model expressing Cre recombinase from the Cebpa promoter and a conditional EYFP allele. We show that Cebpa/EYFP(+) cells represent a significant subset of multipotent hematopoietic progenitors, which predominantly give rise to myeloid cells in steady-state hematopoiesis. C/EBPα induced a strong myeloid gene expression signature and down-regulated E2A-induced regulators of early lymphoid development. In addition, Cebpa/EYFP(+) cells compose a fraction of early thymic progenitors with robust myeloid potential. However, Cebpa/EYFP(+) multipotent hematopoietic progenitors and early thymic progenitors retained the ability to develop into erythroid and T-lymphoid lineages, respectively. These findings support an instructive but argue against a lineage-restrictive role of C/EBPα in multipotent hematopoietic and thymic progenitors. PMID:20807890

  18. Dnmt3a Regulates Myeloproliferation and Liver-Specific Expansion of Hematopoietic Stem and Progenitor Cells

    PubMed Central

    Guryanova, Olga A.; Lieu, Yen K.; Garrett-Bakelman, Francine E.; Spitzer, Barbara; Glass, Jacob L.; Shank, Kaitlyn; Valencia Martinez, Ana Belen; Rivera, Sharon A.; Durham, Benjamin H.; Rapaport, Franck; Keller, Matthew D.; Pandey, Suveg; Bastian, Lennart; Tovbin, Daniel; Weinstein, Abby R.; Teruya-Feldstein, Julie; Abdel-Wahab, Omar; Santini, Valeria; Mason, Christopher E.; Melnick, Ari M.; Mukherjee, Siddhartha; Levine, Ross L.

    2015-01-01

    DNMT3A mutations are observed in myeloid malignancies, including myeloproliferative neoplasms (MPN), myelodysplastic syndromes (MDS), and acute myeloid leukemia (AML). Transplantation studies have elucidated an important role for Dnmt3a in stem cell self-renewal and in myeloid differentiation. Here we investigated the impact of conditional hematopoietic Dnmt3a loss on disease phenotype in primary mice. Mx1-Cre-mediated Dnmt3a ablation led to the development of a lethal, fully penetrant myeloproliferative neoplasm with myelodysplasia (MDS/MPN) characterized by peripheral cytopenias and by marked, progressive hepatomegaly. We detected expanded stem/progenitor populations in the liver of Dnmt3a-ablated mice. The MDS/MPN induced by Dnmt3a ablation was transplantable, including the marked hepatomegaly. Homing studies showed that Dnmt3a-deleted bone marrow cells preferentially migrated to the liver. Gene expression and DNA methylation analyses of progenitor cell populations identified differential regulation of hematopoietic regulatory pathways, including fetal liver hematopoiesis transcriptional programs. These data demonstrate that Dnmt3a ablation in the hematopoietic system leads to myeloid transformation in vivo, with cell autonomous aberrant tissue tropism and marked extramedullary hematopoiesis (EMH) with liver involvement. Hence, in addition to the established role of Dnmt3a in regulating self-renewal, Dnmt3a regulates tissue tropism and limits myeloid progenitor expansion in vivo. PMID:26710888

  19. Distinct myeloid progenitor-differentiation pathways identified through single-cell RNA sequencing.

    PubMed

    Drissen, Roy; Buza-Vidas, Natalija; Woll, Petter; Thongjuea, Supat; Gambardella, Adriana; Giustacchini, Alice; Mancini, Elena; Zriwil, Alya; Lutteropp, Michael; Grover, Amit; Mead, Adam; Sitnicka, Ewa; Jacobsen, Sten Eirik W; Nerlov, Claus

    2016-06-01

    According to current models of hematopoiesis, lymphoid-primed multi-potent progenitors (LMPPs) (Lin(-)Sca-1(+)c-Kit(+)CD34(+)Flt3(hi)) and common myeloid progenitors (CMPs) (Lin(-)Sca-1(+)c-Kit(+)CD34(+)CD41(hi)) establish an early branch point for separate lineage-commitment pathways from hematopoietic stem cells, with the notable exception that both pathways are proposed to generate all myeloid innate immune cell types through the same myeloid-restricted pre-granulocyte-macrophage progenitor (pre-GM) (Lin(-)Sca-1(-)c-Kit(+)CD41(-)FcγRII/III(-)CD150(-)CD105(-)). By single-cell transcriptome profiling of pre-GMs, we identified distinct myeloid differentiation pathways: a pathway expressing the gene encoding the transcription factor GATA-1 generated mast cells, eosinophils, megakaryocytes and erythroid cells, and a pathway lacking expression of that gene generated monocytes, neutrophils and lymphocytes. These results identify an early hematopoietic-lineage bifurcation that separates the myeloid lineages before their segregation from other hematopoietic-lineage potential. PMID:27043410

  20. Underground Adaptation to a Hostile Environment: Acute Myeloid Leukemia vs. Natural Killer Cells

    PubMed Central

    Dulphy, Nicolas; Chrétien, Anne-Sophie; Khaznadar, Zena; Fauriat, Cyril; Nanbakhsh, Arash; Caignard, Anne; Chouaib, Salem; Olive, Daniel; Toubert, Antoine

    2016-01-01

    Acute myeloid leukemia (AML) is a heterogeneous group of malignancies which incidence increases with age. The disease affects the differentiation of hematopoietic stem or precursor cells in the bone marrow and can be related to abnormal cytogenetic and/or specific mutational patterns. AML blasts can be sensitive to natural killer (NK) cell antitumor response. However, NK cells are frequently defective in AML patients leading to tumor escape. NK cell defects affect not only the expression of the activating NK receptors, including the natural cytotoxicity receptors, the NK group 2, member D, and the DNAX accessory molecule-1, but also cytotoxicity and IFN-γ release. Such perturbations in NK cell physiology could be related to the adaptation of the AML to the immune pressure and more generally to patient’s clinical features. Various mechanisms are potentially involved in the inhibition of NK-cell functions in AML, including defects in the normal lymphopoiesis, reduced expression of activating receptors through cell-to-cell contacts, and production of immunosuppressive soluble agents by leukemic blasts. Therefore, the continuous cross-talk between AML and NK cells participates to the leukemia immune escape and eventually to patient’s relapse. Methods to restore or stimulate NK cells seem to be attractive strategies to treat patients once the complete remission is achieved. Moreover, our capacity in stimulating the NK cell functions could lead to the development of preemptive strategies to eliminate leukemia-initiating cells before the emergence of the disease in elderly individuals presenting preleukemic mutations in hematopoietic stem cells. PMID:27014273

  1. IGK with conserved IGKV/IGKJ repertoire is expressed in acute myeloid leukemia and promotes leukemic cell migration

    PubMed Central

    Sun, Xiaoping; He, Zhiqiao; Hu, Fanlei; Chen, Lei; Bueso-Ramos, Carlos E.

    2015-01-01

    We have previously reported that immunoglobulin heavy chain genes were expressed in myeloblasts and mature myeloid cells. In this study, we further demonstrated that rearranged Ig κ light chain was also frequently expressed in acute myeloid leukemia cell lines (6/6), primary myeloblasts from patients with acute myeloid leukemia (17/18), and mature monocytes (11/12) and neutrophils (3/12) from patients with non-hematopoietic neoplasms, but not or only rarely expressed in mature neutrophils (0/8) or monocytes (1/8) from healthy individuals. Interestingly, myeloblasts and mature monocytes/neutrophils shared several restricted IGKV and IGKJ gene usages but with different expression frequency. Surprisingly, almost all of the acute myeloid leukemia-derived IGKV showed somatic hypermutation; in contrast, mature myeloid cells-derived IGKV rarely had somatic hypermutation. More importantly, although IGK expression appeared not to affect cell proliferation, reduced IGK expression led to a decrease in cell migration in acute myeloid leukemia cell lines HL-60 and NB4, whereas increased IGK expression promoted their motility. In summary, IGK is expressed in myeloblasts and mature myeloid cells from patients with non-hematopoietic neoplasms, and is involved in cell migration. These results suggest that myeloid cells-derived IgK may have a role in leukemogenesis and may serve as a novel tumor marker for monitoring minimal residual disease and developing target therapy. PMID:26429876

  2. Hematopoietic Stem Cell Niche in Health and Disease.

    PubMed

    Hoggatt, Jonathan; Kfoury, Youmna; Scadden, David T

    2016-05-23

    Regulation of stem cells in adult tissues is a key determinant of how well an organism can respond to the stresses of physiological challenge and disease. This is particularly true of the hematopoietic system, where demands on host defenses can call for an acute increase in cell production. Hematopoietic stem cells receive the regulatory signals for cell production in adult mammals in the bone marrow, a tissue with higher-order architectural and functional organization than previously appreciated. Here, we review the data defining particular structural components and heterologous cells in the bone marrow that participate in hematopoietic stem cell function. Further, we explore the case for stromal-hematopoietic cell interactions contributing to neoplastic myeloid disease. As the hematopoietic regulatory networks in the bone marrow are revealed, it is anticipated that strategies will emerge for how to enhance or inhibit production of specific blood cells. In that way, the control of hematopoiesis will enter the domain of therapies to modulate broad aspects of hematopoiesis, both normal and malignant. PMID:27193455

  3. Immunotherapy for acute myeloid leukemia.

    PubMed

    Jurcic, Joseph G

    2005-09-01

    Immunotherapeutic strategies have become part of standard cancer treatment. Chimeric and humanized antibodies have demonstrated activity against a variety of tumors. Although the humanized anti-CD33 antibody HuM195 has only modest activity against overt acute myeloid leukemia (AML), it can eliminate minimal residual disease in acute promyelocytic leukemia. High-dose radioimmunotherapy with b-particle-emitting isotopes targeting CD33, CD45, and CD66 can potentially allow intensification of antileukemic therapy before hematopoietic stem cell transplantation. Conversely, a-particle immunotherapy with isotopes such as bismuth-213 or actinium-225 offers the possibility of selective tumor cell kill while sparing surrounding normal tissues. Targeted chemotherapy with the anti-CD33- calicheamicin construct gemtuzumab ozogamicin has produced remissions in relapsed AML and appears promising when used in combination with standard chemotherapy for newly diagnosed AML. T-cell recognition of peptide antigens presented on the cell surface in combination with major histocompatibility complex antigen provides another potentially promising approach for the treatment of AML. PMID:16091194

  4. spib is required for primitive myeloid development in Xenopus.

    PubMed

    Costa, Ricardo M B; Soto, Ximena; Chen, Yaoyao; Zorn, Aaron M; Amaya, Enrique

    2008-09-15

    Vertebrate blood formation occurs in 2 spatially and temporally distinct waves, so-called primitive and definitive hematopoiesis. Although definitive hematopoiesis has been extensively studied, the development of primitive myeloid blood has received far less attention. In Xenopus, primitive myeloid cells originate in the anterior ventral blood islands, the equivalent of the mammalian yolk sac, and migrate out to colonize the embryo. Using fluorescence time-lapse video microscopy, we recorded the migratory behavior of primitive myeloid cells from their birth. We show that these cells are the first blood cells to differentiate in the embryo and that they are efficiently recruited to embryonic wounds, well before the establishment of a functional vasculature. Furthermore, we isolated spib, an ETS transcription factor, specifically expressed in primitive myeloid precursors. Using spib antisense morpholino knockdown experiments, we show that spib is required for myeloid specification, and, in its absence, primitive myeloid cells retain hemangioblast-like characteristics and fail to migrate. Thus, we conclude that spib sits at the top of the known genetic hierarchy that leads to the specification of primitive myeloid cells in amphibians. PMID:18594023

  5. Myeloid lineage skewing due to exacerbated NF-κB signaling facilitates osteopenia in Scurfy mice

    PubMed Central

    Chen, T H-P; Swarnkar, G; Mbalaviele, G; Abu-Amer, Y

    2015-01-01

    Immune surveillance through Foxp3+ regulatory T cells plays a crucial role in bone homeostasis. Scurfy, the mouse model of autoimmune IPEX syndrome, bears a loss-of-function mutation in Foxp3 that leads to multi-organ inflammation. Herein, we report that scurfy mice exhibit severe bone loss mediated by accelerated osteoclastogenesis. Mechanistically, Foxp3 deficiency results in the upregulation of NF-κB in T helper cells through the loss of repressive Foxp3/NEMO interaction, thereby unleashing NF-κB-mediated over-production of pro-osteoclastogenic cytokines. Flow cytometry analysis shows marked increase in lin-Sca-1+c-kit+ hematopoietic stem cells (LSK HSCs) and granulocyte/macrophage progenitors (GMPs) in bone marrow of scurfy mice with corresponding exacerbated osteoclastogenic potential, implying that osteoclast progenitors are affected at a very primitive stage in this disorder. Scurfy LSK HSCs exhibit greater sensitivity to M-CSF and contain abundant PU.1+ Sf LSK HSCs compared with WT. Accordingly, genetic or pharmacological inhibition of M-CSF or mTOR signaling, but not IL-17 signaling, attenuates osteoclastogenesis and osteopenia in scurfy. Thus, our study suggests that Foxp3 deficiency leads to osteopenia owing to dysregulated NF-κB activity and subsequent cytokine-mediated hyper-proliferation of myeloid precursors, and positions the NF-κB pathway as a potential target for therapeutic intervention for this disorder. PMID:25880090

  6. t(3;21)(q26;q22): a recurring chromosomal abnormality in therapy-related myelodysplastic syndrome and acute myeloid leukemia.

    PubMed

    Rubin, C M; Larson, R A; Anastasi, J; Winter, J N; Thangavelu, M; Vardiman, J W; Rowley, J D; Le Beau, M M

    1990-12-15

    We have identified an identical reciprocal translocation between the long arms of chromosomes 3 and 21 with breakpoints at bands 3q26 and 21q22, [t(3;21)(q26;q22)], in the malignant cells from five adult patients with therapy-related myelodysplastic syndrome (t-MDS) or acute myeloid leukemia (t-AML). Primary diagnoses were Hodgkin's disease in two patients and ovarian carcinoma, breast cancer, and polycythemia vera in one patient each. Patients had been treated with chemotherapy including an alkylating agent for their primary disease 1 to 18 years before the development of t-MDS or t-AML. We have not observed the t(3;21) in over 1,500 patients with a myelodysplastic syndrome or acute myeloid leukemia arising de novo or in over 1,000 patients with lymphoid malignancies. We have previously reported that the t(3;21) occurs in Philadelphia chromosome-positive chronic myelogenous leukemia (CML). Thus, the t(3;21) appears to be limited to t-MDS/t-AML and CML, both of which represent malignant disorders of an early hematopoietic precursor cell. These results provide a new focus for the study of therapy-related leukemia at the molecular level. PMID:2265251

  7. GABP transcription factor is required for myeloid differentiation, in part, through its control of Gfi-1 expression

    PubMed Central

    Yang, Zhong-Fa; Drumea, Karen; Cormier, James; Wang, Junling; Zhu, Xuejun

    2011-01-01

    GABP is an ets transcription factor that regulates genes that are required for myeloid differentiation. The tetrameric GABP complex includes GABPα, which binds DNA via its ets domain, and GABPβ, which contains the transcription activation domain. To examine the role of GABP in myeloid differentiation, we generated mice in which Gabpa can be conditionally deleted in hematopoietic tissues. Gabpa knockout mice rapidly lost myeloid cells, and residual myeloid cells were dysplastic and immunophenotypically abnormal. Bone marrow transplantation demonstrated that Gabpα null cells could not contribute to the myeloid compartment because of cell intrinsic defects. Disruption of Gabpa was associated with a marked reduction in myeloid progenitor cells, and Gabpα null myeloid cells express reduced levels of the transcriptional repressor, Gfi-1. Gabp bound and activated the Gfi1 promoter, and transduction of Gabpa knockout bone marrow with Gfi1 partially rescued defects in myeloid colony formation and myeloid differentiation. We conclude that Gabp is required for myeloid differentiation due, in part, to its regulation of the tran-scriptional repressor Gfi-1. PMID:21705494

  8. Hematopoietic tissue repair under chronic low daily dose irradiation

    SciTech Connect

    Seed, T.M.

    1994-12-01

    The capacity of the hematopoietic system to repair constantly accruing cellular damage under chronic, low daily dose gamma irradiation is essential for the maintenance of a functional hematopoietic system, and, in turn, long term survival. In certain individuals, however, such continuous cycles of damage and repair provide an essential inductive environment for selected types of hematopathologies, e.g., myeloid leukemia (ML). We have been studying temporal and causal relationships between hematopoietic capacity, associated repair functions, and propensities for hematologic disease in canines under variable levels of chronic radiation stress (0.3{minus}26.3 cGy d{sup {minus}1}). Results indicate that the maximum exposure rate tolerated by the hematopoietic system is highly individual-specific and is based largely on the degree to which repair capacity, and, in turn, hematopoietic restoration, is augmented under chronic exposure. In low-tolerance individuals (prone to aplastic anemia, subgroup (1), the failure to augment basic m-pair functions seemingly results in a progressive accumulation of genetic and cellular damage within vital progenitorial marrow compartments particularly marked within erythroid compartments. that results in loss of reproductive capacity and ultimately in collapse of the hematopoietic system. The high-tolerance individuals (radioaccomodated and either prone- or not prone to ML, subgroup 2 & 3 appear to minimize the accumulating damage effect of daily exposures by extending repair functions, which preserves reproductive integrity and fosters regenerative hematopoietic responses. As the strength of the regenerative response manifests the extent of repair augmentation, the relatively strong response of high- tolerance individuals progressing to patent ML suggests an insufficiency of repair quality rather than repair quantity.

  9. BRAF-V600E expression in precursor versus differentiated dendritic cells defines clinically distinct LCH risk groups

    PubMed Central

    Berres, Marie-Luise; Lim, Karen Phaik Har; Peters, Tricia; Price, Jeremy; Takizawa, Hitoshi; Salmon, Hélène; Idoyaga, Juliana; Ruzo, Albert; Lupo, Philip J.; Hicks, M. John; Shih, Albert; Simko, Stephen J.; Abhyankar, Harshal; Chakraborty, Rikhia; Leboeuf, Marylene; Beltrão, Monique; Lira, Sérgio A.; Heym, Kenneth M.; Clausen, Björn E.; Bigley, Venetia; Collin, Matthew; Manz, Markus G.; McClain, Kenneth

    2014-01-01

    Langerhans cell histiocytosis (LCH) is a clonal disorder with elusive etiology, characterized by the accumulation of CD207+ dendritic cells (DCs) in inflammatory lesions. Recurrent BRAF-V600E mutations have been reported in LCH. In this study, lesions from 100 patients were genotyped, and 64% carried the BRAF-V600E mutation within infiltrating CD207+ DCs. BRAF-V600E expression in tissue DCs did not define specific clinical risk groups but was associated with increased risk of recurrence. Strikingly, we found that patients with active, high-risk LCH also carried BRAF-V600E in circulating CD11c+ and CD14+ fractions and in bone marrow (BM) CD34+ hematopoietic cell progenitors, whereas the mutation was restricted to lesional CD207+ DC in low-risk LCH patients. Importantly, BRAF-V600E expression in DCs was sufficient to drive LCH-like disease in mice. Consistent with our findings in humans, expression of BRAF-V600E in BM DC progenitors recapitulated many features of the human high-risk LCH, whereas BRAF-V600E expression in differentiated DCs more closely resembled low-risk LCH. We therefore propose classification of LCH as a myeloid neoplasia and hypothesize that high-risk LCH arises from somatic mutation of a hematopoietic progenitor, whereas low-risk disease arises from somatic mutation of tissue-restricted precursor DCs. PMID:24638167

  10. Comparative study of hematopoietic differentiation between human embryonic stem cell lines.

    PubMed

    Melichar, Heather; Li, Ou; Ross, Jenny; Haber, Hilary; Cado, Dragana; Nolla, Hector; Robey, Ellen A; Winoto, Astar

    2011-01-01

    Directed differentiation of human embryonic stem cells (hESCs) into any desired cell type has been hailed as a therapeutic promise to cure many human diseases. However, substantial roadblocks still exist for in vitro differentiation of hESCs into distinct cell types, including T lymphocytes. Here we examined the hematopoietic differentiation potential of six different hESC lines. We compare their ability to develop into CD34(+) or CD34(+)CD45(+) hematopoietic precursor populations under several differentiation conditions. Comparison of lymphoid potential of hESC derived- and fetal tissue derived-hematopoietic precursors was also made. We found diverse hematopoietic potential between hESC lines depending on the culture or passage conditions. In contrast to fetal-derived hematopoietic precursors, none of the CD34(+) precursors differentiated from hESCs were able to develop further into T cells. These data underscore the difficulties in the current strategy of hESC forward differentiation and highlight distinct differences between CD34(+) hematopoietic precursors generated in vitro versus in vivo. PMID:21603627

  11. [Clinical and genetic background of familial myelodysplasia and acute myeloid leukemia].

    PubMed

    Király, Péter Attila; Kállay, Krisztián; Marosvári, Dóra; Benyó, Gábor; Szőke, Anita; Csomor, Judit; Bödör, Csaba

    2016-02-21

    Myelodysplastic syndrome and acute myeloid leukaemia are mainly sporadic diseases, however, rare familial cases exist. These disorders are considered rare, but are likely to be more common than currently appreciated, and are characterized by the autosomal dominant mutations of hematopoietic transcription factors. These syndromes have typical phenotypic features and are associated with an increased risk for developing overt malignancy. Currently, four recognized syndromes could be separated: familial acute myeloid leukemia with mutated CEBPA, familial myelodysplastic syndrome/acute myeloid leukemia with mutated GATA2, familial platelet disorder with propensity to myeloid malignancy with RUNX1 mutations, and telomere biology disorders due to mutations of TERC or TERT. Furthermore, there are new, emerging syndromes associated with germline mutations in novel genes including ANKRD26, ETV6, SRP72 or DDX41. This review will discuss the current understanding of the genetic basis and clinical presentation of familial leukemia and myelodysplasia. PMID:26876264

  12. Functions of TET Proteins in Hematopoietic Transformation

    PubMed Central

    Han, Jae-A; An, Jungeun; Ko, Myunggon

    2015-01-01

    DNA methylation is a well-characterized epigenetic modification that plays central roles in mammalian development, genomic imprinting, X-chromosome inactivation and silencing of retrotransposon elements. Aberrant DNA methylation pattern is a characteristic feature of cancers and associated with abnormal expression of oncogenes, tumor suppressor genes or repair genes. Ten-eleven-translocation (TET) proteins are recently characterized dioxygenases that catalyze progressive oxidation of 5-methylcytosine to produce 5-hydroxymethylcytosine and further oxidized derivatives. These oxidized methylcytosines not only potentiate DNA demethylation but also behave as independent epigenetic modifications per se. The expression or activity of TET proteins and DNA hydroxymethylation are highly dysregulated in a wide range of cancers including hematologic and non-hematologic malignancies, and accumulating evidence points TET proteins as a novel tumor suppressor in cancers. Here we review DNA demethylation-dependent and -independent functions of TET proteins. We also describe diverse TET loss-of-function mutations that are recurrently found in myeloid and lymphoid malignancies and their potential roles in hematopoietic transformation. We discuss consequences of the deficiency of individual Tet genes and potential compensation between different Tet members in mice. Possible mechanisms underlying facilitated oncogenic transformation of TET-deficient hematopoietic cells are also described. Lastly, we address non-mutational mechanisms that lead to suppression or inactivation of TET proteins in cancers. Strategies to restore normal 5mC oxidation status in cancers by targeting TET proteins may provide new avenues to expedite the development of promising anti-cancer agents. PMID:26552488

  13. Hematopoietic ontogeny and its relevance for pediatric leukemias.

    PubMed

    Udroiu, Ion; Sgura, Antonella

    2016-03-01

    Fetal and infant hematopoiesis display characteristics different from the adult one: our suggestion is that these features may help to explain the peculiar incidence rates of acute leukemias. Hematopoietic stem cells (HSCs) are fast-cycling (those in adults instead are largely quiescent) and studies in mice demonstrated that their relative contribution to myelo- and lymphopoiesis varies during development. We hypothesize that during development some of the "hits" needed for the onset of leukemia are usually occurring (being part of the normal development), so leukemogenesis needs less mutations than in adults to take place and therefore it's more probable. The switch between the relative incidence of acute myeloid and lymphoid leukemias may be related to the changes of the percentage of lymphoid-deficient and lymphoid-proficient sub-set of HSCs during development. Further investigations may clarify this hypothesis, elucidating also the roles of the different microenvironments in determining the myeloid/lymphoid predisposition of the HSCs. PMID:26880643

  14. Erythropoietin guides multipotent hematopoietic progenitor cells toward an erythroid fate

    PubMed Central

    Grover, Amit; Mancini, Elena; Moore, Susan; Mead, Adam J.; Atkinson, Deborah; Rasmussen, Kasper D.; O’Carroll, Donal; Jacobsen, Sten Eirik W.

    2014-01-01

    The erythroid stress cytokine erythropoietin (Epo) supports the development of committed erythroid progenitors, but its ability to act on upstream, multipotent cells remains to be established. We observe that high systemic levels of Epo reprogram the transcriptomes of multi- and bipotent hematopoietic stem/progenitor cells in vivo. This induces erythroid lineage bias at all lineage bifurcations known to exist between hematopoietic stem cells (HSCs) and committed erythroid progenitors, leading to increased erythroid and decreased myeloid HSC output. Epo, therefore, has a lineage instructive role in vivo, through suppression of non-erythroid fate options, demonstrating the ability of a cytokine to systematically bias successive lineage choices in favor of the generation of a specific cell type. PMID:24493804

  15. Aging, Clonality, and Rejuvenation of Hematopoietic Stem Cells.

    PubMed

    Akunuru, Shailaja; Geiger, Hartmut

    2016-08-01

    Aging is associated with reduced organ function and increased disease incidence. Hematopoietic stem cell (HSC) aging driven by both cell intrinsic and extrinsic factors is linked to impaired HSC self-renewal and regeneration, aging-associated immune remodeling, and increased leukemia incidence. Compromised DNA damage responses and the increased production of reactive oxygen species (ROS) have been previously causatively attributed to HSC aging. However, recent paradigm-shifting concepts, such as global epigenetic and cytoskeletal polarity shifts, cellular senescence, as well as the clonal selection of HSCs upon aging, provide new insights into HSC aging mechanisms. Rejuvenating agents that can reprogram the epigenetic status of aged HSCs or senolytic drugs that selectively deplete senescent cells provide promising translational avenues for attenuating hematopoietic aging and, potentially, alleviating aging-associated immune remodeling and myeloid malignancies. PMID:27380967

  16. Changes in the use of hematopoietic stem cell transplantation: a model for diffusion of medical technology

    PubMed Central

    Gratwohl, Alois; Schwendener, Alvin; Baldomero, Helen; Gratwohl, Michael; Apperley, Jane; Niederwieser, Dietger; Frauendorfer, Karl

    2010-01-01

    Background Innovations in hematology spread rapidly. Factors affecting the speed of introduction, international diffusion, and durability of use of innovations are, however, poorly understood. Design and Methods We used data on 251,106 hematopoietic stem cell transplants from 591 teams in 36 European countries to analyze the increase and decrease in such transplants for breast cancer and chronic myeloid leukemia and the replacement of bone marrow by peripheral blood as the source of stem cells as processes of diffusion. Regression analyses were used to measure the quantitative impact of defined macro- and microeconomic factors, to look for significant associations (t-test), and to describe the coefficient of determination or explanatory content (R2). Results Gross national income per capita, World Bank category, team density, team distribution, team size, team experience and, team innovator status were all significantly associated with some or all of the changes. The analyses revealed different patterns of associations and a wide range of explanatory content. Macro- and micro-economic factors were sufficient to explain the increase of allogeneic hematopoietic stem cell transplants in general (R2 = 78.41%) and for chronic myeloid leukemia in particular (R2 = 79.39%). They were insufficient to explain the changes in stem cell source (R2 =26.79% autologous hematopoietic stem cell transplants; R2 = 9.67% allogeneic hematopoietic stem cell transplants) or the decreases in hematopoietic stem cell transplants (R2 =10.22% breast cancer; R2=33.17% chronic myeloid leukemia). Conclusions The diffusion of hematopoietic stem cell transplants is more complex than previously thought. Availability of resources, evidence, external regulations and, expectations were identified as key determinants. These data might serve as a model for diffusion of medical technology in general. PMID:20378578

  17. In vivo evidence for an instructive role of fms-like tyrosine kinase-3 (FLT3) ligand in hematopoietic development.

    PubMed

    Tsapogas, Panagiotis; Swee, Lee Kim; Nusser, Anja; Nuber, Natko; Kreuzaler, Matthias; Capoferri, Giuseppina; Rolink, Hannie; Ceredig, Rhodri; Rolink, Antonius

    2014-04-01

    Cytokines are essential regulators of hematopoiesis, acting in an instructive or permissive way. Fms-like tyrosine kinase 3 ligand (FLT3L) is an important cytokine for the development of several hematopoietic populations. Its receptor (FLT3) is expressed on both myeloid and lymphoid progenitors and deletion of either the receptor or its ligand leads to defective developmental potential of hematopoietic progenitors. In vivo administration of FLT3L promotes expansion of progenitors with combined myeloid and lymphoid potential. To investigate further the role of this cytokine in hematopoietic development, we generated transgenic mice expressing high levels of human FLT3L. These transgenic mice displayed a dramatic expansion of dendritic and myeloid cells, leading to splenomegaly and blood leukocytosis. Bone marrow myeloid and lymphoid progenitors were significantly increased in numbers but retained their developmental potential. Furthermore, the transgenic mice developed anemia together with a reduction in platelet numbers. FLT3L was shown to rapidly reduce the earliest erythroid progenitors when injected into wild-type mice, indicating a direct negative role of the cytokine on erythropoiesis. We conclude that FLT3L acts on multipotent progenitors in an instructive way, inducing their development into myeloid/lymphoid lineages while suppressing their megakaryocyte/erythrocyte potential. PMID:24463214

  18. In vivo evidence for an instructive role of fms-like tyrosine kinase-3 (FLT3) ligand in hematopoietic development

    PubMed Central

    Tsapogas, Panagiotis; Swee, Lee Kim; Nusser, Anja; Nuber, Natko; Kreuzaler, Matthias; Capoferri, Giuseppina; Rolink, Hannie; Ceredig, Rhodri; Rolink, Antonius

    2014-01-01

    Cytokines are essential regulators of hematopoiesis, acting in an instructive or permissive way. Fms-like tyrosine kinase 3 ligand (FLT3L) is an important cytokine for the development of several hematopoietic populations. Its receptor (FLT3) is expressed on both myeloid and lymphoid progenitors and deletion of either the receptor or its ligand leads to defective developmental potential of hematopoietic progenitors. In vivo administration of FLT3L promotes expansion of progenitors with combined myeloid and lymphoid potential. To investigate further the role of this cytokine in hematopoietic development, we generated transgenic mice expressing high levels of human FLT3L. These transgenic mice displayed a dramatic expansion of dendritic and myeloid cells, leading to splenomegaly and blood leukocytosis. Bone marrow myeloid and lymphoid progenitors were significantly increased in numbers but retained their developmental potential. Furthermore, the transgenic mice developed anemia together with a reduction in platelet numbers. FLT3L was shown to rapidly reduce the earliest erythroid progenitors when injected into wild-type mice, indicating a direct negative role of the cytokine on erythropoiesis. We conclude that FLT3L acts on multipotent progenitors in an instructive way, inducing their development into myeloid/lymphoid lineages while suppressing their megakaryocyte/erythrocyte potential. PMID:24463214

  19. The SKI proto-oncogene enhances the in vivo repopulation of hematopoietic stem cells and causes myeloproliferative disease

    PubMed Central

    Singbrant, Sofie; Wall, Meaghan; Moody, Jennifer; Karlsson, Göran; Chalk, Alistair M.; Liddicoat, Brian; Russell, Megan R.; Walkley, Carl R.; Karlsson, Stefan

    2014-01-01

    The proto-oncogene SKI is highly expressed in human myeloid leukemia and also in murine hematopoietic stem cells. However, its operative relevance in these cells remains elusive. We have over-expressed SKI to define its intrinsic role in hematopoiesis and myeloid neoplasms, which resulted in a robust competitive advantage upon transplantation, a complete dominance of the stem and progenitor compartments, and a marked enhancement of myeloid differentiation at the expense of other lineages. Accordingly, enforced expression of SKI induced a gene signature associated with hematopoietic stem cells and myeloid differentiation, as well as hepatocyte growth factor signaling. Here we demonstrate that, in contrast to what has generally been assumed, the significant impact of SKI on hematopoiesis is independent of its ability to inhibit TGF-beta signaling. Instead, myeloid progenitors expressing SKI are partially dependent on functional hepatocyte growth factor signaling. Collectively our results demonstrate that SKI is an important regulator of hematopoietic stem cell activity and its overexpression leads to myeloproliferative disease. PMID:24415629

  20. What Is Acute Myeloid Leukemia?

    MedlinePlus

    ... about acute myeloid leukemia? What is acute myeloid leukemia? Cancer starts when cells in a part of ... the body from doing their jobs. Types of leukemia Not all leukemias are the same. There are ...

  1. Ectopic bone formation in severely combat-injured orthopedic patients -- a hematopoietic niche.

    PubMed

    Davis, Thomas A; Lazdun, Yelena; Potter, Benjamin K; Forsberg, Jonathan A

    2013-09-01

    Combat-related heterotopic ossification (HO) has emerged as a common and problematic complication of modern wartime extremity injuries, contributing to substantial patient morbidity and loss of function. We have previously reported that HO-forming patients exhibit a more pronounced systemic and local inflammatory response very early in the wound healing process. Moreover, traumatized muscle-derived mesenchymal progenitor cells from these patients have a skewed differentiation potential toward bone. Here, we demonstrate that HO lesions excised from this patient population contain highly vascularized, mature, cancellous bone containing adipogenic marrow. Histologic analysis showed immature hematopoietic cells located within distinct foci in perivascular regions. The adipogenic marrow often contained low numbers of functional erythroid (BFU-E), myeloid (CFU-GM, CFU-M) and multilineage (CFU-GEMM) colony-forming hematopoietic progenitor cells (HPCs). Conversely, tissue from control muscle and non-HO traumatic wound granulation tissue showed no evidence of hematopoietic progenitor cell activity. In summary, our findings suggest that ectopic bone can provide an appropriate hematopoietic microenvironment for supporting the proliferation and differentiation of HPCs. This reactive and vibrant cell population may help maintain normal hematopoietic function, particularly in those with major extremity amputations who have sustained both massive blood loss, prompting systemic marrow stimulation, as well as loss of available native active marrow space. These findings begin to characterize the functional biology of ectopic bone and elucidate the interactions between HPC and non-hematopoietic cell types within the ectopic intramedullary hematopoietic microenvironmental niche identified. PMID:23727270

  2. The enhanced in vitro hematopoietic activity of leridistim, a chimeric dual G-CSF and IL-3 receptor agonist.

    PubMed

    Abegg, A L; Vickery, L E; Bremer, M E; Donnelly, A M; Doshi, P D; Evans, M L; Thurman, T L; Braford, S R; Caparon, M H; Bauer, S C; Giri, J G; Welply, J K; McKearn, J P; Smith, W G

    2002-03-01

    The in vitro activity of leridistim was characterized for cell proliferation, generation of colony-forming units (CFU) and differentiation of CD34+ cells. In AML-193.1.3 cells, leridistim exhibited a significant increase in potency compared to rhG-CSF, SC-65303 (an IL-3 receptor agonist) or an equimolar combination of rhG-CSF and SC-65303. CFU-GM assays demonstrated that at 50% of the maximum response, the relative potency of leridistim was 12-fold greater than the combination of rhG-CSF and rhIL-3 and 44-fold more potent than rhG-CSF alone. In multi-lineage CFU assays, a combination of erythropoietin (rhEPO) and leridistim resulted in greater numbers of BFU-E, CFU-GEMM and CFU-Mk than rhEPO alone. Ex vivo culture of peripheral blood or bone marrow CD34+ cells with leridistim substantially increased total viable cells over cultures stimulated with rhG-CSF, SC-65303, or a combination of rhG-CSF and SC-65303. Culture with leridistim, resulted in a greater increase in myeloid (CD15+/CD11b+), monocytic (CD41-/CD14+) and megakaryocytic (CD41+/CD14-) precursor cells without depleting the progenitor pool (CD34+/CD15-/CD11b-). These results demonstrate that leridistim is a more potent stimulator of hematopoietic proliferation and differentiation than the single receptor agonists (rhG-CSF and SC-65303) either alone or combined. These unique attributes suggest that leridistim may enhance hematopoietic reconstitution following myelosuppressive chemotherapy. PMID:11896534

  3. 'Acute myeloid leukemia: a comprehensive review and 2016 update'.

    PubMed

    De Kouchkovsky, I; Abdul-Hay, M

    2016-01-01

    Acute myeloid leukemia (AML) is the most common acute leukemia in adults, with an incidence of over 20 000 cases per year in the United States alone. Large chromosomal translocations as well as mutations in the genes involved in hematopoietic proliferation and differentiation result in the accumulation of poorly differentiated myeloid cells. AML is a highly heterogeneous disease; although cases can be stratified into favorable, intermediate and adverse-risk groups based on their cytogenetic profile, prognosis within these categories varies widely. The identification of recurrent genetic mutations, such as FLT3-ITD, NMP1 and CEBPA, has helped refine individual prognosis and guide management. Despite advances in supportive care, the backbone of therapy remains a combination of cytarabine- and anthracycline-based regimens with allogeneic stem cell transplantation for eligible candidates. Elderly patients are often unable to tolerate such regimens, and carry a particularly poor prognosis. Here, we review the major recent advances in the treatment of AML. PMID:27367478

  4. A Rare Complication Developing After Hematopoietic Stem Cell Transplantation: Wernicke’s Encephalopathy

    PubMed Central

    Solmaz, Soner; Gereklioğlu, Çiğdem; Tan, Meliha; Demir, Şenay; Yeral, Mahmut; Korur, Aslı; Boğa, Can; Özdoğu, Hakan

    2015-01-01

    Thiamine is a water-soluble vitamin. Thiamine deficiency can present as a central nervous system disorder known as Wernicke’s encephalopathy, which classically manifests as confusion, ataxia, and ophthalmoplegia. Wernicke’s encephalopathy has rarely been reported following hematopoietic stem cell transplantation. Herein, we report Wernicke’s encephalopathy in a patient with acute myeloid leukemia who had been receiving prolonged total parenteral nutrition after haploidentical allogeneic hematopoietic stem cell transplantation. To the best of our knowledge, this is the first case reported from Turkey in the literature. PMID:25912759

  5. Leukomogenic factors downregulate heparanase expression in acute myeloid leukemia cells

    SciTech Connect

    Eshel, Rinat; Ben-Zaken, Olga; Vainas, Oded; Nadir, Yona; Minucci, Saverio; Polliack, Aaron; Naparstek, Ella; Vlodavsky, Israel; Katz, Ben-Zion; E-mail: bkatz@tasmc.healt.gov.il

    2005-10-07

    Heparanase is a heparan sulfate-degrading endoglycosidase expressed by mature monocytes and myeloid cells, but not by immature hematopoietic progenitors. Heparanase gene expression is upregulated during differentiation of immature myeloid cells. PML-RAR{alpha} and PLZF-RAR{alpha} fusion gene products associated with acute promyelocytic leukemia abrogate myeloid differentiation and heparanase expression. AML-Eto, a translocation product associated with AML FAB M2, also downregulates heparanase gene expression. The common mechanism that underlines the activity of these three fusion gene products involves the recruitment of histone deacetylase complexes to specific locations within the DNA. We found that retinoic acid that dissociates PML-RAR{alpha} from the DNA, and which is used to treat acute promyelocytic leukemia patients, restores heparanase expression to normal levels in an acute promyelocytic leukemia cell line. The retinoic acid effects were also observed in primary acute promyelocytic leukemia cells and in a retinoic acid-treated acute promyelocytic leukemia patient. Histone deacetylase inhibitor reverses the downregulation of heparanase expression induced by the AML-Eto fusion gene product in M2 type AML. In summary, we have characterized a link between leukomogenic factors and the downregulation of heparanase in myeloid leukemic cells.

  6. Human herpesvirus 7 infection of lymphoid and myeloid cell lines transduced with an adenovirus vector containing the CD4 gene.

    PubMed Central

    Yasukawa, M; Inoue, Y; Ohminami, H; Sada, E; Miyake, K; Tohyama, T; Shimada, T; Fujita, S

    1997-01-01

    It has been reported recently that CD4 is a major component of the receptor for human herpesvirus 7 (HHV-7), which has been newly identified as a T-lymphotropic virus. To investigate further the role of CD4 in HHV-7 infection, we examined the susceptibility to HHV-7 infection of various CD4-negative or weakly positive cell lines into which the cDNA for CD4 was transferred using an adenovirus vector (Adex1CACD4). Of 13 cell lines transduced with Adex1CACD4, including T-lymphoid, B-lymphoid, monocytoid, and myeloid cell lines, one T-lymphoid cell line, one monocytoid cell line, and two cell lines established from the blast crisis of chronic myelogenous leukemia showed high susceptibility to HHV-7 infection. Taken together with the results of previous studies, these data suggest strongly that CD4 is a major component of the binding receptor for HHV-7. This study also shows that HHV-7 may be able to infect CD4-positive hematopoietic precursor cells as well as T lymphocytes. PMID:8995705

  7. Brachial Plexus Involvement of Myeloid Sarcoma Detected by Reconstruction Magnetic Resonance Neurography.

    PubMed

    Sugiyama, Atsuhiko; Ito, Shoichi; Sugita, Yasumasa; Shimada, Jun-Ichiro; Takeuchi, Masahiro; Hirano, Shigeki; Kuwabara, Satoshi

    2015-01-01

    Myeloid sarcoma is a rare hematological disorder that presents as an extramedullary mass of immature myeloid precursors. We herein present the case of a 57-year-old man with a seven-month history of progressive weakness in the right upper extremity. Reconstruction magnetic resonance neurography showed a marked enlargement of the right brachial plexus. Fluorodeoxyglucose positron emission tomography revealed a radioactive lesion in the sacrum, in addition to the right brachial plexus, and a biopsy of the sacrum revealed myeloid sarcoma. The brachial plexus lesion was also regarded as myeloid sarcoma because of the treatment response. Isolated myeloid sarcoma involving the brachial plexus is very rare and its diagnosis is difficult as there was neither a history of leukemia nor bone marrow involvement in this patient. In this case, reconstructed magnetic resonance neurography was useful for detecting the brachial plexus mass lesion which led to an early diagnosis and good recovery. PMID:26328656

  8. EVOLUTION OF MYELOID CELLS

    PubMed Central

    Barreda, Daniel R.; Neely, Harold R.; Flajnik, Martin F.

    2015-01-01

    In 1882, Elie Metchnikoff identified myeloid-like cells from starfish larvae responding to the invasion by a foreign body (rose thorn). This marked the origins of the study of innate immunity, and an appreciation that cellular immunity is already well established in these “primitive” organisms. This chapter focuses on these myeloid cells as well as the newest members of this family, the dendritic cells (DC), and explores their evolutionary origins. Our goal is to provide evolutionary context for the development of the multilayered immune system of mammals, where myeloid cells now serve as central effectors of innate immunity and regulators of adaptive immunity. Overall, we find that core contributions of myeloid cells to the regulation of inflammation are based on mechanisms that have been honed over hundreds of millions of years of evolution. Using phagocytosis as a platform, we show how fairly simple beginnings have offered a robust foundation onto which additional control features have been integrated, resulting in central regulatory nodes that now manage multi-factorial aspects of homeostasis and immunity. PMID:27337471

  9. Spleens of myelofibrosis patients contain malignant hematopoietic stem cells

    PubMed Central

    Wang, Xiaoli; Prakash, Sonam; Lu, Min; Tripodi, Joseph; Ye, Fei; Najfeld, Vesna; Li, Yan; Schwartz, Myron; Weinberg, Rona; Roda, Paul; Orazi, Attilio; Hoffman, Ronald

    2012-01-01

    Cancer stem cell behavior is thought to be largely determined by intrinsic properties and by regulatory signals provided by the microenvironment. Myelofibrosis (MF) is characterized by hematopoiesis occurring not only in the marrow but also in extramedullary sites such as the spleen. In order to study the effects of these different microenvironments on primitive malignant hematopoietic cells, we phenotypically and functionally characterized splenic and peripheral blood (PB) MF CD34+ cells from patients with MF. MF spleens contained greater numbers of malignant primitive HPCs than PB. Transplantation of PB MF CD34+ cells into immunodeficient (NOD/SCID/IL2Rγnull) mice resulted in a limited degree of donor cell chimerism and a differentiation program skewed toward myeloid lineages. By contrast, transplanted splenic MF CD34+ cells achieved a higher level of chimerism and generated both myeloid and lymphoid cells that contained molecular or cytogenetic abnormalities indicating their malignant nature. Only splenic MF CD34+ cells were able to sustain hematopoiesis for prolonged periods (9 months) and were able to engraft secondary recipients. These data document the existence of MF stem cells (MF-SCs) that reside in the spleens of MF patients and demonstrate that these MF-SCs retain a differentiation program identical to that of normal hematopoietic stem cells. PMID:23023702

  10. Two Hemocyte Lineages Exist in Silkworm Larval Hematopoietic Organ

    PubMed Central

    Nakahara, Yuichi; Kanamori, Yasushi; Kiuchi, Makoto; Kamimura, Manabu

    2010-01-01

    Background Insects have multiple hemocyte morphotypes with different functions as do vertebrates, however, their hematopoietic lineages are largely unexplored with the exception of Drosophila melanogaster. Methodology/Principal Findings To study the hematopoietic lineage of the silkworm, Bombyx mori, we investigated in vivo and in vitro differentiation of hemocyte precursors in the hematopoietic organ (HPO) into the four mature hemocyte subsets, namely, plasmatocytes, granulocytes, oenocytoids, and spherulocytes. Five days after implantation of enzymatically-dispersed HPO cells from a GFP-expressing transgenic line into the hemocoel of normal larvae, differentiation into plasmatocytes, granulocytes and oenocytoids, but not spherulocytes, was observed. When the HPO cells were cultured in vitro, plasmatocytes appeared rapidly, and oenocytoids possessing prophenol oxidase activity appeared several days later. HPO cells were also able to differentiate into a small number of granulocytes, but not into spherulocytes. When functionally mature plasmatocytes were cultured in vitro, oenocytoids were observed 10 days later. These results suggest that the hemocyte precursors in HPO first differentiate into plasmatocytes, which further change into oenocytoids. Conclusions/Significance From these results, we propose that B. mori hemocytes can be divided into two major lineages, a granulocyte lineage and a plasmatocyte-oenocytoid lineage. The origins of the spherulocytes could not be determined in this study. We construct a model for the hematopoietic lineages at the larval stage of B. mori. PMID:20676370

  11. Redefining Langerhans Cell Histiocytosis as a Myeloid Dysplasia and Identifying B | Division of Cancer Prevention

    Cancer.gov

    DESCRIPTION (provided by applicant): Redefining Langerhans Cell Histiocytosis as a Myeloid Dysplasia and Identifying Biomarkers for Early Detection and Risk Assessment. This application addresses Program Announcement PA-09-197: Biomarkers for Early Detection of Hematopoietic Malignancies (R01). The overall aim of this project is to identify novel biomarkers that may be used to diagnose and treat patients with Langerhans Cell Histiocytosis (LCH). LCH occurs with similar frequency as other rare malignancies including Hodgkin's lymphoma and AML. |

  12. IPC: professional type 1 interferon-producing cells and plasmacytoid dendritic cell precursors.

    PubMed

    Liu, Yong-Jun

    2005-01-01

    Type 1 interferon-(alpha, beta, omega)-producing cells (IPCs), also known as plasmacytoid dendritic cell precursors (pDCs), represent 0.2%-0.8% of peripheral blood mononuclear cells in both humans and mice. IPCs display plasma cell morphology, selectively express Toll-like receptor (TLR)-7 and TLR9, and are specialized in rapidly secreting massive amounts of type 1 interferon following viral stimulation. IPCs can promote the function of natural killer cells, B cells, T cells, and myeloid DCs through type 1 interferons during an antiviral immune response. At a later stage of viral infection, IPCs differentiate into a unique type of mature dendritic cell, which directly regulates the function of T cells and thus links innate and adaptive immune responses. After more than two decades of effort by researchers, IPCs finally claim their place in the hematopoietic chart as the most important cell type in antiviral innate immunity. Understanding IPC biology holds future promise for developing cures for infectious diseases, cancer, and autoimmune diseases. PMID:15771572

  13. Immature MEF2C-dysregulated T-cell leukemia patients have an early T-cell precursor acute lymphoblastic leukemia gene signature and typically have non-rearranged T-cell receptors

    PubMed Central

    Zuurbier, Linda; Gutierrez, Alejandro; Mullighan, Charles G.; Canté-Barrett, Kirsten; Gevaert, A. Olivier; de Rooi, Johan; Li, Yunlei; Smits, Willem K.; Buijs-Gladdines, Jessica G.C.A.M.; Sonneveld, Edwin; Look, A. Thomas; Horstmann, Martin; Pieters, Rob; Meijerink, Jules P.P.

    2014-01-01

    Three distinct immature T-cell acute lymphoblastic leukemia entities have been described including cases that express an early T-cell precursor immunophenotype or expression profile, immature MEF2C-dysregulated T-cell acute lymphoblastic leukemia cluster cases based on gene expression analysis (immature cluster) and cases that retain non-rearranged TRG@ loci. Early T-cell precursor acute lymphoblastic leukemia cases exclusively overlap with immature cluster samples based on the expression of early T-cell precursor acute lymphoblastic leukemia signature genes, indicating that both are featuring a single disease entity. Patients lacking TRG@ rearrangements represent only 40% of immature cluster cases, but no further evidence was found to suggest that cases with absence of bi-allelic TRG@ deletions reflect a distinct and even more immature disease entity. Immature cluster/early T-cell precursor acute lymphoblastic leukemia cases are strongly enriched for genes expressed in hematopoietic stem cells as well as genes expressed in normal early thymocyte progenitor or double negative-2A T-cell subsets. Identification of early T-cell precursor acute lymphoblastic leukemia cases solely by defined immunophenotypic criteria strongly underestimates the number of cases that have a corresponding gene signature. However, early T-cell precursor acute lymphoblastic leukemia samples correlate best with a CD1 negative, CD4 and CD8 double negative immunophenotype with expression of CD34 and/or myeloid markers CD13 or CD33. Unlike various other studies, immature cluster/early T-cell precursor acute lymphoblastic leukemia patients treated on the COALL-97 protocol did not have an overall inferior outcome, and demonstrated equal sensitivity levels to most conventional therapeutic drugs compared to other pediatric T-cell acute lymphoblastic leukemia patients. PMID:23975177

  14. CCAAT/enhancer binding protein alpha is a regulatory switch sufficient for induction of granulocytic development from bipotential myeloid progenitors.

    PubMed

    Radomska, H S; Huettner, C S; Zhang, P; Cheng, T; Scadden, D T; Tenen, D G

    1998-07-01

    The transcription factor CCAAT/enhancer binding protein alpha (C/EBPalpha) regulates a number of myeloid cell-specific genes. To delineate the role of C/EBPalpha in human granulopoiesis, we studied its expression and function in human primary cells and bipotential (granulocytic/monocytic) myeloid cell lines. We show that the expression of C/EBPalpha initiates with the commitment of multipotential precursors to the myeloid lineage, is specifically upregulated during granulocytic differentiation, and is rapidly downregulated during the alternative monocytic pathway. Conditional expression of C/EBPalpha alone in stably transfected bipotential cells triggers neutrophilic differentiation, concomitant with upregulation of the granulocyte-specific granulocyte colony-stimulating factor receptor and secondary granule protein genes. Moreover, induced expression of C/EBPalpha in bipotential precursors blocks their monocytic differentiation program. These results indicate that C/EBPalpha serves as a myeloid differentiation switch acting on bipotential precursors and directing them to mature to granulocytes. PMID:9632814

  15. Hematopoietic stem cell transplantation

    PubMed Central

    Hatzimichael, Eleftheria; Tuthill, Mark

    2010-01-01

    More than 25,000 hematopoietic stem cell transplantations (HSCTs) are performed each year for the treatment of lymphoma, leukemia, immune-deficiency illnesses, congenital metabolic defects, hemoglobinopathies, and myelodysplastic and myeloproliferative syndromes. Before transplantation, patients receive intensive myeloablative chemoradiotherapy followed by stem cell “rescue.” Autologous HSCT is performed using the patient’s own hematopoietic stem cells, which are harvested before transplantation and reinfused after myeloablation. Allogeneic HSCT uses human leukocyte antigen (HLA)-matched stem cells derived from a donor. Survival after allogeneic transplantation depends on donor–recipient matching, the graft-versus-host response, and the development of a graft versus leukemia effect. This article reviews the biology of stem cells, clinical efficacy of HSCT, transplantation procedures, and potential complications. PMID:24198516

  16. Antagonism between MCL-1 and PUMA governs stem/progenitor cell survival during hematopoietic recovery from stress

    PubMed Central

    Delbridge, Alex R. D.; Opferman, Joseph T.; Grabow, Stephanie

    2015-01-01

    Understanding the critical factors that govern recovery of the hematopoietic system from stress, such as during anticancer therapy and bone marrow transplantation, is of clinical significance. We investigated the importance of the prosurvival proteins myeloid cell leukemia-1 (MCL-1) and B-cell lymphoma–extra large (BCL-XL) in stem/progenitor cell survival and fitness during hematopoietic recovery from stress. Loss of a single Mcl-1 allele, which reduced MCL-1 protein levels, severely compromised hematopoietic recovery from myeloablative challenge and following bone marrow transplantation, whereas BCL-XL was dispensable in both contexts. We identified inhibition of proapoptotic p53 upregulated modulator of apoptosis (PUMA) as the key role of MCL-1 in both settings, with Mcl-1+/−;Puma−/− mice completely protected from the deleterious effects of loss of 1 Mcl-1 allele. These results reveal the molecular mechanisms that govern cell survival during hematopoietic recovery from stress. PMID:25847014

  17. A NEW ROLE FOR THE HUMAN PLACENTA AS A HEMATOPOIETIC SITE THROUGHOUT GESTATION

    PubMed Central

    Bárcena, Alicia; Muench, Marcus O.; Kapidzic, Mirhan; Fisher, Susan J.

    2009-01-01

    We investigated whether the human placenta plays a role in embryonic and fetal hematopoietic development. Two cell populations—CD34++CD45low and CD34+CD45low—were found in chorionic villi. CD34++CD45low cells display many markers that are characteristic of multipotent primitive hematopoietic progenitors and hematopoietic stem cells (HSCs). Clonogenic in vitro assays showed that CD34++CD45low cells contained colony-forming units-culture (CFU-C) with myeloid and erythroid potential and differentiated into CD56+ NK cells and CD19+ B cells in culture. CD34+CD45low cells were mostly enriched in erythroid- and myeloid-committed progenitors. The number of CD34++CD45low cells increased throughout gestation in parallel with placental mass. However, their density (cells per gram of tissue) reached its peak at 5–8 weeks, decreasing more than sevenfold from the ninth week onward. In addition to multipotent progenitors, the placenta contained intermediate progenitors, indicative of active hematopoiesis. Together, these data suggest that the human placenta is potentially an important hematopoietic organ, opening the possibility of banking placental HSCs along with cord blood for transplantation. PMID:19208786

  18. IL12B expression is sustained by a heterogenous population of myeloid lineages during tuberculosis

    PubMed Central

    Reeme, Allison E.; Miller, Halli E.; Robinson, Richard T.

    2015-01-01

    Summary IL12B is required for resistance to Mycobacterium tuberculosis (Mtb) infection, promoting the initiation and maintenance of Mtb-specific effector responses. While this makes the IL12-pathway an attractive target for experimental tuberculosis (TB) therapies, data regarding what lineages express IL12B after infection is established are limited. This is not obvious in the lung, an organ in which both hematopoietic and non-hematopoietic lineages produce IL12p40 upon pathogen encounter. Here, we use radiation bone marrow chimeras and Yet40 reporter mice to determine what lineages produce IL12p40 during experimental TB. We observed that hematopoietic IL12p40-production was sufficient to control Mtb, with no contribution by non-hematopoietic lineages. Furthermore, rather than being produced by a single subset, IL12p40 was produced by cells that were heterogenous in their size, granularity, autofluorescence and expression of CD11c, CD11b and CD8α. While depending on the timepoint and tissue examined, the surface phenotype of IL12p40-producers most closely resembled macrophages based on previous surveys of lung myeloid lineages. Importantly, depletion of CDllchi cells during infection had no affect on lung IL12p40-concentrations. Collectively, our data demonstrate that IL12p40 production is sustained by a heterogenous population of myeloid lineages during experimental TB, and that redundant mechanisms of IL12p40-production exist when CD11chi lineages are absent. PMID:23491716

  19. Discovery of survival factor for primitive chronic myeloid leukemia cells using induced pluripotent stem cells.

    PubMed

    Suknuntha, Kran; Ishii, Yuki; Tao, Lihong; Hu, Kejin; McIntosh, Brian E; Yang, David; Swanson, Scott; Stewart, Ron; Wang, Jean Y J; Thomson, James; Slukvin, Igor

    2015-11-01

    A definitive cure for chronic myeloid leukemia (CML) requires identifying novel therapeutic targets to eradicate leukemia stem cells (LSCs). However, the rarity of LSCs within the primitive hematopoietic cell compartment remains a major limiting factor for their study in humans. Here we show that primitive hematopoietic cells with typical LSC features, including adhesion defect, increased long-term survival and proliferation, and innate resistance to tyrosine kinase inhibitor (TKI) imatinib, can be generated de novo from reprogrammed primary CML cells. Using CML iPSC-derived primitive leukemia cells, we discovered olfactomedin 4 (OLFM4) as a novel factor that contributes to survival and growth of somatic lin(-)CD34(+) cells from bone marrow of patients with CML in chronic phase, but not primitive hematopoietic cells from normal bone marrow. Overall, this study shows the feasibility and advantages of using reprogramming technology to develop strategies for targeting primitive leukemia cells. PMID:26561938

  20. Discovery of survival factor for primitive chronic myeloid leukemia cells using induced pluripotent stem cells

    PubMed Central

    Suknuntha, Kran; Ishii, Yuki; Tao, Lihong; Hu, Kejin; McIntosh, Brian E.; Yang, David; Swanson, Scott; Stewart, Ron; Wang, Jean Y.J.; Thomson, James; Slukvin, Igor

    2016-01-01

    A definitive cure for chronic myeloid leukemia (CML) requires identifying novel therapeutic targets to eradicate leukemia stem cells (LSCs). However, the rarity of LSCs within the primitive hematopoietic cell compartment remains a major limiting factor for their study in humans. Here we show that primitive hematopoietic cells with typical LSC features, including adhesion defect, increased long-term survival and proliferation, and innate resistance to tyrosine kinase inhibitor (TKI) imatinib, can be generated de novo from reprogrammed primary CML cells. Using CML iPSC-derived primitive leukemia cells, we discovered olfactomedin 4 (OLFM4) as a novel factor that contributes to survival and growth of somatic lin−CD34+ cells from bone marrow of patients with CML in chronic phase, but not primitive hematopoietic cells from normal bone marrow. Overall, this study shows the feasibility and advantages of using reprogramming technology to develop strategies for targeting primitive leukemia cells. PMID:26561938

  1. Genetically Modified T-cell Immunotherapy in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia

    ClinicalTrials.gov

    2016-08-10

    Adult Acute Myeloid Leukemia in Remission; Donor; Early Relapse of Acute Myeloid Leukemia; Late Relapse of Acute Myeloid Leukemia; Recurrent Adult Acute Myeloid Leukemia; Secondary Acute Myeloid Leukemia

  2. Identification of Reprogrammed Myeloid Cell Transcriptomes in NSCLC

    PubMed Central

    Gupta, Ravi; Fischer, Kari R.; Choi, Hyejin; El Rayes, Tina; Ryu, Seongho; Nasar, Abu; Spinelli, Cathy F.; Andrews, Weston; Elemento, Olivier; Nolan, Daniel; Stiles, Brendon; Rafii, Shahin; Narula, Navneet; Davuluri, Ramana; Altorki, Nasser K.; Mittal, Vivek

    2015-01-01

    Lung cancer is the leading cause of cancer related mortality worldwide, with non-small cell lung cancer (NSCLC) as the most prevalent form. Despite advances in treatment options including minimally invasive surgery, CT-guided radiation, novel chemotherapeutic regimens, and targeted therapeutics, prognosis remains dismal. Therefore, further molecular analysis of NSCLC is necessary to identify novel molecular targets that impact prognosis and the design of new-targeted therapies. In recent years, tumor “activated/reprogrammed” stromal cells that promote carcinogenesis have emerged as potential therapeutic targets. However, the contribution of stromal cells to NSCLC is poorly understood. Here, we show increased numbers of bone marrow (BM)-derived hematopoietic cells in the tumor parenchyma of NSCLC patients compared with matched adjacent non-neoplastic lung tissue. By sorting specific cellular fractions from lung cancer patients, we compared the transcriptomes of intratumoral myeloid compartments within the tumor bed with their counterparts within adjacent non-neoplastic tissue from NSCLC patients. The RNA sequencing of specific myeloid compartments (immature monocytic myeloid cells and polymorphonuclear neutrophils) identified differentially regulated genes and mRNA isoforms, which were inconspicuous in whole tumor analysis. Genes encoding secreted factors, including osteopontin (OPN), chemokine (C-C motif) ligand 7 (CCL7) and thrombospondin 1 (TSP1) were identified, which enhanced tumorigenic properties of lung cancer cells indicative of their potential as targets for therapy. This study demonstrates that analysis of homogeneous stromal populations isolated directly from fresh clinical specimens can detect important stromal genes of therapeutic value. PMID:26046767

  3. Large-Scale Hematopoietic Differentiation of Human Induced Pluripotent Stem Cells Provides Granulocytes or Macrophages for Cell Replacement Therapies

    PubMed Central

    Lachmann, Nico; Ackermann, Mania; Frenzel, Eileen; Liebhaber, Steffi; Brennig, Sebastian; Happle, Christine; Hoffmann, Dirk; Klimenkova, Olga; Lüttge, Doreen; Buchegger, Theresa; Kühnel, Mark Philipp; Schambach, Axel; Janciauskiene, Sabina; Figueiredo, Constanca; Hansen, Gesine; Skokowa, Julia; Moritz, Thomas

    2015-01-01

    Summary Interleukin-3 (IL-3) is capable of supporting the proliferation of a broad range of hematopoietic cell types, whereas granulocyte colony-stimulating factor (G-CSF) and macrophage CSF (M-CSF) represent critical cytokines in myeloid differentiation. When this was investigated in a pluripotent-stem-cell-based hematopoietic differentiation model, IL-3/G-CSF or IL-3/M-CSF exposure resulted in the continuous generation of myeloid cells from an intermediate myeloid-cell-forming complex containing CD34+ clonogenic progenitor cells for more than 2 months. Whereas IL-3/G-CSF directed differentiation toward CD45+CD11b+CD15+CD16+CD66b+ granulocytic cells of various differentiation stages up to a segmented morphology displaying the capacity of cytokine-directed migration, respiratory burst response, and neutrophil-extracellular-trap formation, exposure to IL-3/M-CSF resulted in CD45+CD11b+CD14+CD163+CD68+ monocyte/macrophage-type cells capable of phagocytosis and cytokine secretion. Hence, we show here that myeloid specification of human pluripotent stem cells by IL-3/G-CSF or IL-3/M-CSF allows for prolonged and large-scale production of myeloid cells, and thus is suited for cell-fate and disease-modeling studies as well as gene- and cell-therapy applications. PMID:25680479

  4. Use of chromosome engineering to model a segmental deletion of chromosome band 7q22 found in myeloid malignancies.

    PubMed

    Wong, Jasmine C Y; Zhang, Yan; Lieuw, Kenneth H; Tran, Mary T; Forgo, Erna; Weinfurtner, Kelley; Alzamora, Pilar; Kogan, Scott C; Akagi, Keiko; Wolff, Linda; Le Beau, Michelle M; Killeen, Nigel; Shannon, Kevin

    2010-06-01

    Monosomy 7 and del(7q) are associated with adverse features in myeloid malignancies. A 2.5-Mb commonly deleted segment (CDS) of chromosome band 7q22 is implicated as harboring a myeloid tumor suppressor gene (TSG); however, molecular analysis of candidate TSGs has not uncovered loss of function. To determine whether haploinsufficiency for the 7q22 CDS contributes to myeloid leukemogenesis, we performed sequential gene targeting to flank a region of orthologous synteny on mouse chromosome band 5A3 with loxP sites. We then generated Mx1-Cre, 5A3(fl) mutant mice and deleted the targeted interval in vivo. Although excision was inefficient, we confirmed somatic deletion of the 5A3 CDS in the hematopoietic stem cell compartment. Mx1-Cre, 5A3(fl) mice show normal hematologic parameters and do not spontaneously develop myeloid malignancies. The 5A3(fl) deletion does not cooperate with oncogenic Kras(G12D) expression, Nf1 inactivation, or retroviral mutagenesis to accelerate leukemia development and did not modulate responsiveness to antileukemia drugs. These studies demonstrate that it is feasible to somatically delete a large chromosomal segment implicated in tumor suppression in hematopoietic cell populations in vivo; however, our data do not support the hypothesis that the 7q22/5A3 CDS interval contains a myeloid TSG. PMID:20233966

  5. The regulation of hematopoietic stem cell populations

    PubMed Central

    Mayani, Hector

    2016-01-01

    Evidence presented over the last few years indicates that the hematopoietic stem cell (HSC) compartment comprises not just one but a number of different cell populations. Based on HSCs’ proliferation and engraftment potential, it has been suggested that there are two classes of HSC, with long- and short-term engraftment potential. HSC heterogeneity seems to involve differentiation capacities as well, since it has been shown that some HSC clones are able to give rise to both myeloid and lymphoid progeny, whereas others are lymphoid deficient. It has been recognized that HSC function depends on intrinsic cell regulators, which are modulated by external signals. Among the former, we can include transcription factors and non-coding RNAs as well as epigenetic modifiers. Among the latter, cytokines and extracellular matrix molecules have been implicated. Understanding the elements and mechanisms that regulate HSC populations is of significant relevance both in biological and in clinical terms, and research in this area still has to face several complex and exciting challenges. PMID:27408695

  6. Common marmoset CD117+ hematopoietic cells possess multipotency.

    PubMed

    Shimada, Shin; Nunomura, Satoshi; Mori, Shuya; Suemizu, Hiroshi; Itoh, Toshio; Takabayashi, Shuji; Okada, Yoshinori; Yahata, Takashi; Shiina, Takashi; Katoh, Hideki; Suzuki, Ryuji; Tani, Kenzaburo; Ando, Kiyoshi; Yagita, Hideo; Habu, Sonoko; Sasaki, Erika; Kametani, Yoshie

    2015-11-01

    Analysis of the hematopoiesis of non-human primates is important to clarify the evolution of primate-specific hematopoiesis and immune regulation. However, the engraftment and development of the primate hematopoietic system are well-documented only in humans and are not clear in non-human primates. Callithrix jacchus (common marmoset, CM) is a New World monkey with a high rate of pregnancy and small size that lives in closed colonies. As stem cell factor (SCF) is an essential molecule for hematopoietic stem cell development in mice and humans, we focused on CD117, the SCF receptor, and examined whether CD117-expressing cells possess the hematopoietic stem/progenitor cell characteristics of newborn marmoset-derived hematopoietic cells that can develop into T cells and B cells. When CD117(+) cell fractions of the bone marrow were transplanted into immunodeficient NOD (non-obese diabetic)/Shi-scid, common γc-null (NOG) mice, these cells engrafted efficiently in the bone marrow and spleens of the NOG mice. The CD117(+) cells developed into myeloid lineage cells, CD20(+) B cells and CD3(+) T cells, which could express CM cytokines in vivo. The development of B cells did not precede that of T cells. The development of CD8(+) T cells was dominant in NOG mice. The engraftment was comparable for both CD117(+)CD34(+) cells and CD117(+)CD34(-) cells. These results suggest that the CD117(+) cell fraction can differentiate into all three cell lineages, and the development of marmoset immunity in the xenogeneic environment follows diverse developmental pathways compared with human immunity. PMID:25977306

  7. Myeloid derived suppressor cells

    PubMed Central

    Waldron, Todd J.; Quatromoni, Jon G.; Karakasheva, Tatiana A.; Singhal, Sunil; Rustgi, Anil K.

    2013-01-01

    The goal of achieving measurable response with cancer immunotherapy requires counteracting the immunosuppressive characteristics of tumors. One of the mechanisms that tumors utilize to escape immunosurveillance is the activation of myeloid derived suppressor cells (MDSCs). Upon activation by tumor-derived signals, MDSCs inhibit the ability of the host to mount an anti-tumor immune response via their capacity to suppress both the innate and adaptive immune systems. Despite their relatively recent discovery and characterization, anti-MDSC agents have been identified, which may improve immunotherapy efficacy. PMID:23734336

  8. The allometry of chronic myeloid leukemia.

    PubMed

    Pacheco, Jorge M; Traulsen, Arne; Dingli, David

    2009-08-01

    Chronic myeloid leukemia (CML) is an acquired neoplastic hematopoietic stem cell (HSC) disorder characterized by the expression of the BCR-ABL oncoprotein. This gene product is necessary and sufficient to explain the chronic phase of CML. The only known cause of CML is radiation exposure leading to a mutation of at least one HSC, although the vast majority of patients with CML do not have a history of radiation exposure. Nonetheless, in humans, significant radiation exposure (after exposure to atomic bomb fallout) leads to disease diagnosis in 3-5 years. In murine models, disease dynamics are much faster and CML is fatal over the span of a few months. Our objective is to develop a model that accounts for CML across all mammals. In the following, we combine a model of CML dynamics in humans with allometric scaling of hematopoiesis across mammals to illustrate the natural history of chronic phase CML in various mammals. We show how a single cell can lead to a fatal illness in mice and humans but a higher burden of CML stem cells is necessary to induce disease in larger mammals such as elephants. The different dynamics of the disease is rationalized in terms of mammalian mass. Our work illustrates the relevance of animal models to understand human disease and highlights the importance of considering the re-scaling of the dynamics that accrues to the same biological process when planning experiments involving different species. PMID:19362566

  9. Induction of Chronic Myeloid Leukemia in Mice.

    PubMed

    Zhang, Haojian; Li, Shaoguang

    2016-01-01

    Chronic myeloid leukemia (CML) is a myeloproliferative disorder derived from a hematopoietic stem cell (HSC), harboring Philadelphia chromosome (Ph chromosome). Formation of the Ph chromosome is caused by a reciprocal translocation between the chromosomes 9 and 22 t(9;22)(q34;q11), resulting in a fusion protein known as BCR-ABL which has constitutive tyrosine kinase activity and promotes the proliferation of leukemia cells via multiple mechanisms. Studies on CML have led to the identification of the first cancer-associated chromosomal abnormality and the subsequent development of tyrosine kinase inhibitors (TKIs) that inhibit BCR-ABL kinase activity in CML. It has become clear that leukemia stem cells (LSCs) in CML are insensitive to inhibition by TKIs, and eradication of LSCs appears to be difficult. Therefore, some of the major issues in current CML therapy are to understand the biology of LSCs and to investigate why LSCs are insensitive to TKIs for developing curative therapeutic strategies. In this regard, application of mouse models recapitulating human CML disease will be critical. In this chapter, we describe methods for induction of CML in mice with BCR-ABL. PMID:27581135

  10. Non-Hematopoietic and Hematopoietic SIRPα Signaling Differently Regulates Murine B Cell Maturation in Bone Marrow and Spleen

    PubMed Central

    Kolan, Shrikant Shantilal; Lejon, Kristina; Koskinen Holm, Cecilia; Sulniute, Rima; Lundberg, Pernilla; Matozaki, Takashi; Oldenborg, Per-Arne

    2015-01-01

    B lymphocyte development occurs in the bone marrow, while final differentiation and maturation can occur in both the bone marrow and the spleen. Here we provide evidence that signal regulatory protein α (SIRPα), an Ig-superfamily ITIM-receptor expressed by myeloid but not by lymphoid cells, is involved in regulating B cell maturation. Lack of SIRPα signaling in adult SIRPα-mutant mice resulted in a reduced maturation of B cells in the bone marrow, evident by reduced numbers of semi-mature IgD+IgMhi follicular type-II (F-II) and mature IgD+IgMlo follicular type-I (F-I) B cells, as well as reduced blood B cell numbers. In addition, lack of SIRPα signaling also impaired follicular B cell maturation in the spleen. Maturing BM or splenic B cells of SIRPα-mutant mice were found to express higher levels of the pro-apoptotic protein BIM and apoptosis was increased among these B cells. Bone marrow reconstitution experiments revealed that the B cell maturation defect in bone marrow and blood was due to lack of SIRPα signaling in non-hematopoietic cells, while hematopoietic SIRPα signaling was important for follicular B cell maturation in the spleen. Adding on to our previous findings of a stromal cell defect in SIRPα-mutant mice was the finding that gene expression of receptor activator of nuclear factor-ĸB ligand (RANKL) was significantly lower in cultured bone marrow stromal cells of SIRPα mutant mice. These data suggest a novel and opposite contribution of SIRPα signaling within non-hematopoietic and hematopoietic cells, respectively, to maintain B cell maturation and to prevent apoptosis in the bone marrow and spleen of adult mice. PMID:26222253

  11. The effects of proliferation and DNA damage on hematopoietic stem cell function determine aging.

    PubMed

    Khurana, Satish

    2016-07-01

    In most of the mammalian tissues, homeostasis as well as injury repair depend upon a small number of resident adult stem cells. The decline in tissue/organ function in aged organisms has been directly linked with poorly functioning stem cells. Altered function of hematopoietic stem cells (HSCs) is at the center of an aging hematopoietic system, a tissue with high cellular turnover. Poorly engrafting, myeloid-biased HSCs with higher levels of DNA damage accumulation are the hallmark features of an aged hematopoietic system. These cells show a higher proliferation rate than their younger counterparts. It was proposed that quiescence of these cells over long period of time leads to accumulation of DNA damage, eventually resulting in poor function/pathological conditions in hematopoietic system. However, various mouse models with premature aging phenotype also show highly proliferative HSCs. This review examines the evidence that links proliferation of HSCs with aging, which leads to functional changes in the hematopoietic system. Developmental Dynamics 245:739-750, 2016. © 2016 Wiley Periodicals, Inc. PMID:26813236

  12. LAPTM5: A novel lysosomal-associated multispanning membrane protein preferentially expressed in hematopoietic cells

    SciTech Connect

    Adra, C.N.; Zhu, Shaochun; Ko, Jone-Long

    1996-07-15

    While a large body of knowledge about cell membrane proteins exists, much less is known about the repertoire and function of integral membrane proteins of intracellular organelles. In looking for novel classes of genes that are functionally important to hematopoietic cells, we have cloned the cDNA for a gene preferentially expressed in adult hematopoietic tissues. During embryonic development the gene is expressed in both hematopoietic and nonhematopoietic tissues. In cell lines the gene is expressed specifically in hematopoietic lineages, whereas in normal adult tissues the mRNA is preferentially detected at high levels in lymphoid and myeloid tissues. The predicted protein is a pentaspanner with no homology to known genes and conserved across evolution. Immunocytological and cell fractionation studies with a specific antibody revealed a protein localizing in lysosomes. The gene, provisionally named LAPTM5, maps to chromosome 1p34. The expression pattern of the gene together with preliminary evidence that the protein interacts with ubiquitin indicates that the protein may have a special functional role during embryogenesis and in adult hematopoietic cells. 53 refs., 9 figs.

  13. The autophagy protein Atg7 is essential for hematopoietic stem cell maintenance

    PubMed Central

    Mortensen, Monika; Soilleux, Elizabeth J.; Djordjevic, Gordana; Tripp, Rebecca; Lutteropp, Michael; Sadighi-Akha, Elham; Stranks, Amanda J.; Glanville, Julie; Knight, Samantha; W. Jacobsen, Sten-Eirik; Kranc, Kamil R.

    2011-01-01

    The role of autophagy, a lysosomal degradation pathway which prevents cellular damage, in the maintenance of adult mouse hematopoietic stem cells (HSCs) remains unknown. Although normal HSCs sustain life-long hematopoiesis, malignant transformation of HSCs leads to leukemia. Therefore, mechanisms protecting HSCs from cellular damage are essential to prevent hematopoietic malignancies. In this study, we crippled autophagy in HSCs by conditionally deleting the essential autophagy gene Atg7 in the hematopoietic system. This resulted in the loss of normal HSC functions, a severe myeloproliferation, and death of the mice within weeks. The hematopoietic stem and progenitor cell compartment displayed an accumulation of mitochondria and reactive oxygen species, as well as increased proliferation and DNA damage. HSCs within the Lin−Sca-1+c-Kit+ (LSK) compartment were significantly reduced. Although the overall LSK compartment was expanded, Atg7-deficient LSK cells failed to reconstitute the hematopoietic system of lethally irradiated mice. Consistent with loss of HSC functions, the production of both lymphoid and myeloid progenitors was impaired in the absence of Atg7. Collectively, these data show that Atg7 is an essential regulator of adult HSC maintenance. PMID:21339326

  14. Hematopoietic activity in putative mouse primordial germ cell populations.

    PubMed

    Scaldaferri, Maria Lucia; Klinger, Francesca Gioia; Farini, Donatella; Di Carlo, Anna; Carsetti, Rita; Giorda, Ezio; De Felici, Massimo

    2015-05-01

    In the present paper, starting from the observation of heterogeneous expression of the GOF-18ΔPE-GFP Pou5f1 (Oct3/4) transgene in putative mouse PGC populations settled in the aorta-gonad-mesonephros (AGM) region, we identified various OCT3/4 positive populations showing distinct expression of PGC markers (BLIMP-1, AP, TG-1, STELLA) and co-expressing several proteins (CD-34, CD-41, FLK-1) and genes (Brachyury, Hox-B4, Scl/Tal-1 and Gata-2) of hematopoietic precursors. Moreover, we found that Oct3/4-GFP(weak) CD-34(weak/high) cells possess robust hematopoietic colony forming activity (CFU) in vitro. These data indicate that the cell population usually considered PGCs moving toward the gonadal ridges encompasses a subset of cells co-expressing several germ cell and hematopoietic markers and possessing hematopoietic activity. These results are discussed within of the current model of germline segregation. PMID:25684074

  15. Acute myeloid leukaemia.

    PubMed

    Khwaja, Asim; Bjorkholm, Magnus; Gale, Rosemary E; Levine, Ross L; Jordan, Craig T; Ehninger, Gerhard; Bloomfield, Clara D; Estey, Eli; Burnett, Alan; Cornelissen, Jan J; Scheinberg, David A; Bouscary, Didier; Linch, David C

    2016-01-01

    Acute myeloid leukaemia (AML) is a disorder characterized by a clonal proliferation derived from primitive haematopoietic stem cells or progenitor cells. Abnormal differentiation of myeloid cells results in a high level of immature malignant cells and fewer differentiated red blood cells, platelets and white blood cells. The disease occurs at all ages, but predominantly occurs in older people (>60 years of age). AML typically presents with a rapid onset of symptoms that are attributable to bone marrow failure and may be fatal within weeks or months when left untreated. The genomic landscape of AML has been determined and genetic instability is infrequent with a relatively small number of driver mutations. Mutations in genes involved in epigenetic regulation are common and are early events in leukaemogenesis. The subclassification of AML has been dependent on the morphology and cytogenetics of blood and bone marrow cells, but specific mutational analysis is now being incorporated. Improvements in treatment in younger patients over the past 35 years has largely been due to dose escalation and better supportive care. Allogeneic haematopoietic stem cell transplantation may be used to consolidate remission in those patients who are deemed to be at high risk of relapse. A plethora of new agents - including those targeted at specific biochemical pathways and immunotherapeutic approaches - are now in trial based on improved understanding of disease pathophysiology. These advances provide good grounds for optimism, although mortality remains high especially in older patients. PMID:27159408

  16. C/EBPβ promotes BCR-ABL-mediated myeloid expansion and leukemic stem cell exhaustion.

    PubMed

    Hayashi, Y; Hirai, H; Kamio, N; Yao, H; Yoshioka, S; Miura, Y; Ashihara, E; Fujiyama, Y; Tenen, D G; Maekawa, T

    2013-03-01

    The BCR-ABL fusion oncoprotein accelerates differentiation and proliferation of myeloid cells during the chronic phase of chronic myeloid leukemia (CP-CML). Here, the role of CCAAT/enhancer binding protein β (C/EBPβ), a regulator for 'emergency granulopoiesis,' in the pathogenesis of CP-CML was examined. C/EBPβ expression was upregulated in Lineage(-) CD34(+) CD38(-) hematopoietic stem cells (HSCs) and myeloid progenitors isolated from bone marrow of patients with CP-CML. In EML cells, a mouse HSC line, BCR-ABL upregulated C/EBPβ, at least in part, through the activation of STAT5. Myeloid differentiation and proliferation induced by BCR-ABL was significantly impaired in C/EBPβ-deficient bone marrow cells in vitro. Mice that were transplanted with BCR-ABL-transduced C/EBPβ knockout bone marrow cells survived longer than mice that received BCR-ABL-transduced wild-type (WT) bone marrow cells. Significantly higher levels of leukemic stem cells were maintained in BCR-ABL-transduced C/EBPβ-deficient cells than in BCR-ABL-transduced WT cells. These results suggest that C/EBPβ is involved in BCR-ABL-mediated myeloid expansion. Further elucidation of the molecular mechanisms underlying the C/EBPβ-mediated stem cell loss might reveal a novel therapeutic strategy for eradication of CML stem cells. PMID:22948537

  17. Hypoxia-inducible factors in human pulmonary arterial hypertension: a link to the intrinsic myeloid abnormalities.

    PubMed

    Farha, Samar; Asosingh, Kewal; Xu, Weiling; Sharp, Jacqueline; George, Deepa; Comhair, Suzy; Park, Margaret; Tang, W H Wilson; Loyd, James E; Theil, Karl; Tubbs, Raymond; Hsi, Eric; Lichtin, Alan; Erzurum, Serpil C

    2011-03-31

    Pulmonary arterial hypertension (PAH) is a proliferative vasculopathy characterized by high circulating CD34(+)CD133(+) proangiogenic progenitors, and endothelial cells that have pathologic expression of hypoxia-inducible factor 1 α (HIF-1α). Here, CD34(+)CD133(+) progenitor cell numbers are shown to be higher in PAH bone marrow, blood, and pulmonary arteries than in healthy controls. The HIF-inducible myeloid-activating factors erythropoietin, stem cell factor (SCF), and hepatocyte growth factor (HGF) are also present at higher than normal levels in PAH blood, and related to disease severity. Primary endothelial cells harvested from human PAH lungs produce greater HGF and progenitor recruitment factor stromal-derived factor 1 α (SDF-1α) than control lung endothelial cells, and thus may contribute to bone marrow activation. Even though PAH patients had normal numbers of circulating blood elements, hematopoietic alterations in myeloid and erythroid lineages and reticulin fibrosis identified a subclinical myeloproliferative process. Unexpectedly, evaluation of bone marrow progenitors and reticulin in nonaffected family members of patients with familial PAH revealed similar myeloid abnormalities. Altogether, the results show that PAH is linked to myeloid abnormalities, some of which may be related to increased production of HIF-inducible factors by diseased pulmonary vasculature, but findings in nonaffected family suggest myeloid abnormalities may be intrinsic to the disease process. PMID:21258008

  18. Hypoxia-inducible factors in human pulmonary arterial hypertension: a link to the intrinsic myeloid abnormalities

    PubMed Central

    Asosingh, Kewal; Xu, Weiling; Sharp, Jacqueline; George, Deepa; Comhair, Suzy; Park, Margaret; Tang, W. H. Wilson; Loyd, James E.; Theil, Karl; Tubbs, Raymond; Hsi, Eric; Lichtin, Alan

    2011-01-01

    Pulmonary arterial hypertension (PAH) is a proliferative vasculopathy characterized by high circulating CD34+CD133+ proangiogenic progenitors, and endothelial cells that have pathologic expression of hypoxia-inducible factor 1 α (HIF-1α). Here, CD34+CD133+ progenitor cell numbers are shown to be higher in PAH bone marrow, blood, and pulmonary arteries than in healthy controls. The HIF-inducible myeloid-activating factors erythropoietin, stem cell factor (SCF), and hepatocyte growth factor (HGF) are also present at higher than normal levels in PAH blood, and related to disease severity. Primary endothelial cells harvested from human PAH lungs produce greater HGF and progenitor recruitment factor stromal-derived factor 1 α (SDF-1α) than control lung endothelial cells, and thus may contribute to bone marrow activation. Even though PAH patients had normal numbers of circulating blood elements, hematopoietic alterations in myeloid and erythroid lineages and reticulin fibrosis identified a subclinical myeloproliferative process. Unexpectedly, evaluation of bone marrow progenitors and reticulin in nonaffected family members of patients with familial PAH revealed similar myeloid abnormalities. Altogether, the results show that PAH is linked to myeloid abnormalities, some of which may be related to increased production of HIF-inducible factors by diseased pulmonary vasculature, but findings in nonaffected family suggest myeloid abnormalities may be intrinsic to the disease process. PMID:21258008

  19. MiR-181 family: regulators of myeloid differentiation and acute myeloid leukemia as well as potential therapeutic targets.

    PubMed

    Su, R; Lin, H-S; Zhang, X-H; Yin, X-L; Ning, H-M; Liu, B; Zhai, P-F; Gong, J-N; Shen, C; Song, L; Chen, J; Wang, F; Zhao, H-L; Ma, Y-N; Yu, J; Zhang, J-W

    2015-06-01

    MicroRNAs have been shown to play an important role in normal hematopoisis and leukemogenesis. Here, we report function and mechanisms of miR-181 family in myeloid differentiation and acute myeloid leukemia (AML). The aberrant overexpression of all the miR-181 family members (miR-181a/b/c/d) was detected in French-American-British M1, M2 and M3 subtypes of adult AML patients. By conducting gain- and loss-of-function experiments, we demonstrated that miR-181a inhibits granulocytic and macrophage-like differentiation of HL-60 cells and CD34+ hematopoietic stem/progenitor cells (HSPCs) by directly targeting and downregulating the expression of PRKCD (which then affected the PRKCD-P38-C/EBPα pathway), CTDSPL (which then affected the phosphorylation of retinoblastoma protein) and CAMKK1. The three genes were also demonstrated to be the targets of miR-181b, miR-181c and miR-181d, respectively. Significantly decreases in the expression levels of the target proteins were detected in AML patients. Inhibition of the expression of miR-181 family members owing to Lenti-miRZip-181a infection in bone marrow blasts of AML patients increased target protein expression levels and partially reversed myeloid differentiation blockage. In the mice implanted with AML CD34+ HSPCs, expression inhibition of the miR-181 family by Lenti-miRZip-181a injection improved myeloid differentiation, inhibited engraftment and infiltration of the leukemic CD34+ cells into the bone marrow and spleen, and released leukemic symptoms. In conclusion, our findings revealed new mechanism of miR-181 family in normal hematopoiesis and AML development, and suggested that expression inhibition of the miR-181 family could provide a new strategy for AML therapy. PMID:25174404

  20. General Information about Childhood Acute Myeloid Leukemia and Other Myeloid Malignancies

    MedlinePlus

    ... Other Myeloid Malignancies Treatment (PDQ®)–Patient Version General Information About Childhood Acute Myeloid Leukemia and Other Myeloid ... the PDQ Pediatric Treatment Editorial Board . Clinical Trial Information A clinical trial is a study to answer ...

  1. The role of tumor suppressor p15Ink4b in the regulation of hematopoietic progenitor cell fate

    PubMed Central

    Humeniuk, R; Rosu-Myles, M; Fares, J; Koller, R; Bies, J; Wolff, L

    2013-01-01

    Epigenetic silencing of the tumor suppressor gene p15Ink4b (CDKN2B) is a frequent event in blood disorders like acute myeloid leukemia and myelodysplastic syndromes. The molecular function of p15Ink4b in hematopoietic differentiation still remains to be elucidated. Our previous study demonstrated that loss of p15Ink4b in mice results in skewing of the differentiation pattern of the common myeloid progenitor towards the myeloid lineage. Here, we investigated a function of p15Ink4b tumor suppressor gene in driving erythroid lineage commitment in hematopoietic progenitors. It was found that p15Ink4b is expressed more highly in committed megakaryocyte–erythroid progenitors than granulocyte–macrophage progenitors. More importantly, mice lacking p15Ink4b have lower numbers of primitive red cell progenitors and a severely impaired response to 5-fluorouracil- and phenylhydrazine-induced hematopoietic stress. Introduction of p15Ink4b into multipotential progenitors produced changes at the molecular level, including activation of mitogen-activated protein kinase\\extracellular signal-regulated kinase (MEK/ERK) signaling, increase GATA-1, erythropoietin receptor (EpoR) and decrease Pu1, GATA-2 expression. These changes rendered cells more permissive to erythroid commitment and less permissive to myeloid commitment, as demonstrated by an increase in early burst-forming unit-erythroid formation with concomitant decrease in myeloid colonies. Our results indicate that p15Ink4b functions in hematopoiesis, by maintaining proper lineage commitment of progenitors and assisting in rapid red blood cells replenishment following stress. PMID:23359317

  2. Dnmt3a loss predisposes murine hematopoietic stem cells to malignant transformation

    PubMed Central

    Mayle, Allison; Yang, Liubin; Rodriguez, Benjamin; Zhou, Ting; Chang, Edmund; Curry, Choladda V.; Challen, Grant A.; Li, Wei; Wheeler, David; Rebel, Vivienne I.

    2015-01-01

    DNA methyltransferase 3A (DNMT3A) is mutated in hematologic malignancies affecting myeloid, mixed, and lymphoid lineages, and these mutations are associated with poor prognosis. Past studies in mice revealed Dnmt3a-knockout (KO) hematopoietic stem cells (HSCs) had increased self-renewal, but no leukemia was observed. Here, all lethally irradiated mice transplanted with Dnmt3a-deleted HSCs died within 1 year. Animals were diagnosed with a spectrum of malignancies similar to those seen in patients with DNMT3A mutations, including myelodysplastic syndrome, acute myeloid leukemia, primary myelofibrosis, and T- and B-cell acute lymphocytic leukemia. In some cases, acquired malignancies exhibited secondary mutations similar to those identified in patients. Loss of Dnmt3a led to disturbed methylation patterns that were distinct in lymphoid and myeloid disease, suggesting lineage-specific methylation aberrations promoted by Dnmt3a loss. Global hypomethylation was observed in all of the malignancies, but lymphoid malignancies also exhibited hypermethylation, particularly at promoter regions. This mouse model underscores the important role of Dnmt3a in normal hematopoietic development and demonstrates that Dnmt3a loss of function confers a preleukemic phenotype on murine HSCs. This model may serve as a tool to study DNMT3A mutation-associated malignancies and for developing targeted strategies for eliminating preleukemic cells for prevention and treatment of hematologic malignancies in the future. PMID:25416277

  3. Reticular dysgenesis–associated AK2 protects hematopoietic stem and progenitor cell development from oxidative stress

    PubMed Central

    Rissone, Alberto; Weinacht, Katja Gabriele; la Marca, Giancarlo; Bishop, Kevin; Giocaliere, Elisa; Jagadeesh, Jayashree; Felgentreff, Kerstin; Dobbs, Kerry; Al-Herz, Waleed; Jones, Marypat; Chandrasekharappa, Settara; Kirby, Martha; Wincovitch, Stephen; Simon, Karen Lyn; Itan, Yuval; DeVine, Alex; Schlaeger, Thorsten; Schambach, Axel; Sood, Raman

    2015-01-01

    Adenylate kinases (AKs) are phosphotransferases that regulate the cellular adenine nucleotide composition and play a critical role in the energy homeostasis of all tissues. The AK2 isoenzyme is expressed in the mitochondrial intermembrane space and is mutated in reticular dysgenesis (RD), a rare form of severe combined immunodeficiency (SCID) in humans. RD is characterized by a maturation arrest in the myeloid and lymphoid lineages, leading to early onset, recurrent, and overwhelming infections. To gain insight into the pathophysiology of RD, we studied the effects of AK2 deficiency using the zebrafish model and induced pluripotent stem cells (iPSCs) derived from fibroblasts of an RD patient. In zebrafish, Ak2 deficiency affected hematopoietic stem and progenitor cell (HSPC) development with increased oxidative stress and apoptosis. AK2-deficient iPSCs recapitulated the characteristic myeloid maturation arrest at the promyelocyte stage and demonstrated an increased AMP/ADP ratio, indicative of an energy-depleted adenine nucleotide profile. Antioxidant treatment rescued the hematopoietic phenotypes in vivo in ak2 mutant zebrafish and restored differentiation of AK2-deficient iPSCs into mature granulocytes. Our results link hematopoietic cell fate in AK2 deficiency to cellular energy depletion and increased oxidative stress. This points to the potential use of antioxidants as a supportive therapeutic modality for patients with RD. PMID:26150473

  4. What Is Chronic Myeloid Leukemia?

    MedlinePlus

    ... leukemia? Next Topic Normal bone marrow and blood What is chronic myeloid leukemia? Cancer starts when cells ... their treatment is the same as for adults. What is leukemia? Leukemia is a cancer that starts ...

  5. Lung epithelium and myeloid cells cooperate to clear acute pneumococcal infection.

    PubMed

    Dudek, M; Puttur, F; Arnold-Schrauf, C; Kühl, A A; Holzmann, B; Henriques-Normark, B; Berod, L; Sparwasser, T

    2016-09-01

    The Gram-positive bacterium Streptococcus pneumoniae causes life-threatening infections, especially among immunocompromised patients. The host's immune system senses S. pneumoniae via different families of pattern recognition receptors, in particular the Toll-like receptor (TLR) family that promotes immune cell activation. Yet, while single TLRs are dispensable for initiating inflammatory responses against S. pneumoniae, the central TLR adapter protein myeloid differentiation factor 88 (MyD88) is of vital importance, as MyD88-deficient mice succumb rapidly to infection. Since MyD88 is ubiquitously expressed in hematopoietic and non-hematopoietic cells, the extent to which MyD88 signaling is required in different cell types to control S. pneumoniae is unknown. Therefore, we used novel conditional knockin mice to investigate the necessity of MyD88 signaling in distinct lung-resident myeloid and epithelial cells for the initiation of a protective immune response against S. pneumoniae. Here, we show that MyD88 signaling in lysozyme M (LysM)- and CD11c-expressing myeloid cells, as well as in pulmonary epithelial cells, is critical to restore inflammatory cytokine and antimicrobial peptide production, leading to efficient neutrophil recruitment and enhanced bacterial clearance. Overall, we show a novel synergistic requirement of compartment-specific MyD88 signaling in S. pneumoniae immunity. PMID:26627460

  6. Lung epithelium and myeloid cells cooperate to clear acute pneumococcal infection

    PubMed Central

    Dudek, M; Puttur, F; Arnold-Schrauf, C; Kühl, A A; Holzmann, B; Henriques-Normark, B; Berod, L; Sparwasser, T

    2016-01-01

    The Gram-positive bacterium Streptococcus pneumoniae causes life-threatening infections, especially among immunocompromised patients. The host's immune system senses S. pneumoniae via different families of pattern recognition receptors, in particular the Toll-like receptor (TLR) family that promotes immune cell activation. Yet, while single TLRs are dispensable for initiating inflammatory responses against S. pneumoniae, the central TLR adapter protein myeloid differentiation factor 88 (MyD88) is of vital importance, as MyD88-deficient mice succumb rapidly to infection. Since MyD88 is ubiquitously expressed in hematopoietic and non-hematopoietic cells, the extent to which MyD88 signaling is required in different cell types to control S. pneumoniae is unknown. Therefore, we used novel conditional knockin mice to investigate the necessity of MyD88 signaling in distinct lung-resident myeloid and epithelial cells for the initiation of a protective immune response against S. pneumoniae. Here, we show that MyD88 signaling in lysozyme M (LysM)– and CD11c-expressing myeloid cells, as well as in pulmonary epithelial cells, is critical to restore inflammatory cytokine and antimicrobial peptide production, leading to efficient neutrophil recruitment and enhanced bacterial clearance. Overall, we show a novel synergistic requirement of compartment-specific MyD88 signaling in S. pneumoniae immunity. PMID:26627460

  7. Occupational exposure to formaldehyde, hematotoxicity and leukemia-specific chromosome changes in cultured myeloid progenitor cells

    PubMed Central

    Zhang, Luoping; Tang, Xiaojiang; Rothman, Nathaniel; Vermeulen, Roel; Ji, Zhiying; Shen, Min; Qiu, Chuangyi; Guo, Weihong; Liu, Songwang; Reiss, Boris; Laura Beane, Freeman; Ge, Yichen; Hubbard, Alan E.; Hua, Ming; Blair, Aaron; Galvan, Noe; Ruan, Xiaolin; Alter, Blanche P.; Xin, Kerry X.; Li, Senhua; Moore, Lee E.; Kim, Sungkyoon; Xie, Yuxuan; Hayes, Richard B.; Azuma, Mariko; Hauptmann, Michael; Xiong, Jun; Stewart, Patricia; Li, Laiyu; Rappaport, Stephen M.; Huang, Hanlin; Fraumeni, Joseph F.; Smith, Martyn T.; Lan, Qing

    2010-01-01

    There are concerns about the health effects of formaldehyde exposure, including carcinogenicity, in light of elevated indoor air levels in new homes and occupational exposures experienced by workers in health care, embalming, manufacturing and other industries. Epidemiological studies suggest that formaldehyde exposure is associated with an increased risk of leukemia. However, the biological plausibility of these findings has been questioned because limited information is available on formaldehyde’s ability to disrupt hematopoietic function. Our objective was to determine if formaldehyde exposure disrupts hematopoietic function and produces leukemia-related chromosome changes in exposed humans. We examined the ability of formaldehyde to disrupt hematopoiesis in a study of 94 workers in China (43 exposed to formaldehyde and 51 frequency-matched controls) by measuring complete blood counts and peripheral stem/progenitor cell colony formation. Further, myeloid progenitor cells, the target for leukemogenesis, were cultured from the workers to quantify the level of leukemia-specific chromosome changes, including monosomy 7 and trisomy 8, in metaphase spreads of these cells. Among exposed workers, peripheral blood cell counts were significantly lowered in a manner consistent with toxic effects on the bone marrow and leukemia-specific chromosome changes were significantly elevated in myeloid blood progenitor cells. These findings suggest that formaldehyde exposure can have an adverse impact on the hematopoietic system and that leukemia induction by formaldehyde is biologically plausible, which heightens concerns about its leukemogenic potential from occupational and environmental exposures. PMID:20056626

  8. The Polycomb Group Protein L3MBTL1 Represses a SMAD5-Mediated Hematopoietic Transcriptional Program in Human Pluripotent Stem Cells

    PubMed Central

    Perna, Fabiana; Vu, Ly P.; Themeli, Maria; Kriks, Sonja; Hoya-Arias, Ruben; Khanin, Raya; Hricik, Todd; Mansilla-Soto, Jorge; Papapetrou, Eirini P.; Levine, Ross L.; Studer, Lorenz; Sadelain, Michel; Nimer, Stephen D.

    2015-01-01

    Summary Epigenetic regulation of key transcriptional programs is a critical mechanism that controls hematopoietic development, and, thus, aberrant expression patterns or mutations in epigenetic regulators occur frequently in hematologic malignancies. We demonstrate that the Polycomb protein L3MBTL1, which is monoallelically deleted in 20q- myeloid malignancies, represses the ability of stem cells to drive hematopoietic-specific transcriptional programs by regulating the expression of SMAD5 and impairing its recruitment to target regulatory regions. Indeed, knockdown of L3MBTL1 promotes the development of hematopoiesis and impairs neural cell fate in human pluripotent stem cells. We also found a role for L3MBTL1 in regulating SMAD5 target gene expression in mature hematopoietic cell populations, thereby affecting erythroid differentiation. Taken together, we have identified epigenetic priming of hematopoietic-specific transcriptional networks, which may assist in the development of therapeutic approaches for patients with anemia. PMID:25754204

  9. Transcriptional Heterogeneity and Lineage Commitment in Myeloid Progenitors.

    PubMed

    Paul, Franziska; Arkin, Ya'ara; Giladi, Amir; Jaitin, Diego Adhemar; Kenigsberg, Ephraim; Keren-Shaul, Hadas; Winter, Deborah; Lara-Astiaso, David; Gury, Meital; Weiner, Assaf; David, Eyal; Cohen, Nadav; Lauridsen, Felicia Kathrine Bratt; Haas, Simon; Schlitzer, Andreas; Mildner, Alexander; Ginhoux, Florent; Jung, Steffen; Trumpp, Andreas; Porse, Bo Torben; Tanay, Amos; Amit, Ido

    2015-12-17

    Within the bone marrow, stem cells differentiate and give rise to diverse blood cell types and functions. Currently, hematopoietic progenitors are defined using surface markers combined with functional assays that are not directly linked with in vivo differentiation potential or gene regulatory mechanisms. Here, we comprehensively map myeloid progenitor subpopulations by transcriptional sorting of single cells from the bone marrow. We describe multiple progenitor subgroups, showing unexpected transcriptional priming toward seven differentiation fates but no progenitors with a mixed state. Transcriptional differentiation is correlated with combinations of known and previously undefined transcription factors, suggesting that the process is tightly regulated. Histone maps and knockout assays are consistent with early transcriptional priming, while traditional transplantation experiments suggest that in vivo priming may still allow for plasticity given strong perturbations. These data establish a reference model and general framework for studying hematopoiesis at single-cell resolution. PMID:26627738

  10. Novel Prognostic and Therapeutic Mutations in Acute Myeloid Leukemia.

    PubMed

    Medinger, Michael; Lengerke, Claudia; Passweg, Jakob

    Acute myeloid leukemia (AML) is a biologically complex and molecularly and clinically heterogeneous disease, and its incidence increases with age. Cytogenetics and mutation testing remain important prognostic tools for treatment after induction therapy. The post-induction treatment is dependent on risk stratification. Despite rapid advances in determination of gene mutations involved in the pathophysiology and biology of AML, and the rapid development of new drugs, treatment improvements changed slowly over the past 30 years, with the majority of patients eventually experiencing relapse and dying of their disease. Allogenic hematopoietic stem cell transplantation remains the best chance of cure for patients with intermediate- or high-risk disease. This review gives an overview about advances in prognostic markers and novel treatment options for AML, focusing on new prognostic and probably therapeutic mutations, and novel drug therapies such as tyrosine kinase inhibitors. PMID:27566651

  11. Decitabine in Treating Patients With Previously Untreated Acute Myeloid Leukemia

    ClinicalTrials.gov

    2016-05-18

    Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Secondary Acute Myeloid Leukemia; Untreated Adult Acute Myeloid Leukemia

  12. Sclerosing extramedullary hematopoietic tumor presenting as an inguinal mass in a patient with primary myelofibrosis: a diagnostic pitfall

    PubMed Central

    Gu, Mi-Jin

    2015-01-01

    Sclerosing extramedullary hematopoietic tumor (SEMHT) is a rare lesion and presented as retroperitoneal or serosal-based mass. A 53-year-old man with a long history of primary myelofibrosis, presented with abdominal distension and inguinal mass. Pathologic examination of inguinal mass revealed a prominent sclerotic background with thick collagen deposits and mono, bi, or tri-lineage hematopoietic tissue containing atypical megakaryocytes and variable proportions of myeloid and erythroid series. The atypical megakaryocytes were positive for Factor VIII and CD61. SEMHT may be misdiagnosed as lymphocyte depleted Hodgkin’s disease, as a mesenchymal neoplasm, or as carcinoma, because of the presence of large atypical cells and marked fibrosis when clinical information regarding PMF is unknown. Awareness of the bizarre atypical megakaryocyte morphology with immature hematopoietic cells and of clinical history is essential to prevent misdiagnosis. PMID:26045874

  13. C/EBP- and Tat-mediated activation of the HIV-1 LTR in CD34+ hematopoietic progenitor cells.

    PubMed

    Quiterio, Shane; Grant, Christian; Hogan, Tricia H; Krebs, Fred C; Wigdahl, Brian

    2003-01-01

    Human immunodeficiency virus type 1 (HIV-1) infection of cells of the monocyte/macrophage lineage within the bone marrow and peripheral blood plays an important role in the pathologic events leading to the development of the acquired immune deficiency syndrome (AIDS) as well as HIV-1 dementia (HIVD). The TF-1 erythro-myeloid cell line is being utilized as a model cellular phenotype to examine HIV-1 infection of a hematopoietic progenitor cell population. Expression of TF-1 cell surface marker RNAs and proteins was characterized by RT-PCR and FACS, respectively, and compared to those of the well characterized U-937 monocytic cell line. Transcription factors in TF-1 and U-937 cells that have been shown to be important for sustaining the expression of HIV-1 LTR activity were also examined. TF-1 cells were shown to contain the transcription factors C/EBP, Sp1, and NF-kappaB. C/EBP- and Tat-mediated induction of the YU-2 LTR was examined. Relative C/EBP induction of the HIV-1 strain YU-2 LTR was greater in TF-1 cells than in U-937 cells. When the C/EBP sites I and II were mutated to sequences with a low relative affinity for C/EBP factors, there was a reduction of Tat-mediated trans-activation in TF-1 cells, but not in U-937 cells. These studies form the foundation for investigations into the relationship between HIV-1 infection of bone marrow and peripheral blood precursor cells of the monocyte/macrophage lineage and pathogenesis associated with HIV-1 infection of the immune and central nervous system (CNS). PMID:12642037

  14. ¹⁹F MRI tracer preserves in vitro and in vivo properties of hematopoietic stem cells.

    PubMed

    Helfer, Brooke M; Balducci, Anthony; Sadeghi, Zhina; O'Hanlon, Charles; Hijaz, Adonis; Flask, Chris A; Wesa, Amy

    2013-01-01

    Hematopoietic stem cells (HSCs) have numerous therapeutic applications including immune reconstitution, enzyme replacement, regenerative medicine, and immunomodulation. The trafficking and persistence of these cells after administration is a fundamental question for future therapeutic applications of HSCs. Here, we describe the safe and efficacious labeling of human CD34(+) HSCs with a novel, self-delivering perfluorocarbon ¹⁹F magnetic resonance imaging (MRI) tracer, which has recently been authorized for use in a clinical trial to track therapeutic cells. While various imaging contrast agents have been used to track cellular therapeutics, the impact of this MRI tracer on HSC function has not previously been studied. Both human CD34(+) and murine bone marrow (BM) HSCs were effectively labeled with the MRI tracer, with only a slight reduction in viability, relative to mock-labeled cells. In a pilot study, ¹⁹F MRI enabled the rapid evaluation of HSC delivery/retention following administration into a rat thigh muscle, revealing the dispersal of HSCs after injection, but not after surgical implantation. To investigate effects on cell functionality, labeled and unlabeled human HSCs were tested in in vitro colony forming unit (CFU) assays, which resulted in equal numbers of total CFU as well as individual CFU types, indicating that labeling did not alter multipotency. Cobblestone assay forming cell precursor frequency was also unaffected, providing additional evidence that stem cell function was preserved after labeling. In vivo tests of multipotency and reconstitution studies in mice with murine BM containing labeled HSCs resulted in normal development of CFU in the spleen, compared to unlabeled cells, and reconstitution of both lymphoid and myeloid compartments. The lack of interference in these complex biological processes provides strong evidence that the function and therapeutic potential of the HSCs are likely maintained after labeling. These data support

  15. Identification of an interleukin-3-regulated aldoketo reductase gene in myeloid cells which may function in autocrine regulation of myelopoiesis.

    PubMed

    Du, Y; Tsai, S; Keller, J R; Williams, S C

    2000-03-10

    The EML hematopoietic progenitor cell line is a model system for studying molecular events regulating myeloid commitment and terminal differentiation. We used representational difference analysis to identify genes that are expressed differentially during myeloid differentiation of EML cells. One gene (named mAKRa) encoded a novel member of the aldoketo reductase (AKR) superfamily of cytosolic NAD(P)(H)-dependent oxidoreductases. mAKRa mRNA was detected in murine hematopoietic tissues including bone marrow, spleen, and thymus. In myeloid cell lines, mAKRa was expressed at highest levels in cells representative of promyelocytes. mAKRa mRNA levels increased rapidly in response to interleukin-3 over the first 24 h of EML cell differentiation when the cells undergo lineage commitment and extensive proliferation. mAKRa mRNA levels decreased later in the differentiation process particularly when the EML cells were cultured with granulocyte/macrophage colony-stimulating factor and retinoic acid to induce terminal granulocytic maturation. mAKRa mRNA levels decreased during retinoic acid-induced terminal granulocytic differentiation of the MPRO promyelocyte cell line. AKRs act as molecular switches by catalyzing the interconversion or inactivation of bioactive molecules including steroids and prostaglandins. We propose that mAKRa may catalyze the production or catabolism of autocrine factors that promote the proliferation and/or lineage commitment of early myeloid progenitors. PMID:10702227

  16. High-affinity FRβ-specific CAR T cells eradicate AML and normal myeloid lineage without HSC toxicity.

    PubMed

    Lynn, R C; Feng, Y; Schutsky, K; Poussin, M; Kalota, A; Dimitrov, D S; Powell, D J

    2016-06-01

    Acute myeloid leukemia (AML) is an aggressive malignancy, and development of new treatments to prolong remissions is warranted. Chimeric antigen receptor (CAR) T-cell therapies appear promising but on-target, off-tumor recognition of antigen in healthy tissues remains a concern. Here we isolated a high-affinity (HA) folate receptor beta (FRβ)-specific single-chain variable fragment (2.48 nm KD) for optimization of FRβ-redirected CAR T-cell therapy for AML. T cells stably expressing the HA-FRβ CAR exhibited greatly enhanced antitumor activity against FRβ(+) AML in vitro and in vivo compared with a low-affinity FRβ CAR (54.3 nm KD). Using the HA-FRβ immunoglobulin G, FRβ expression was detectable in myeloid-lineage hematopoietic cells; however, expression in CD34(+) hematopoietic stem cells (HSCs) was nearly undetectable. Accordingly, HA-FRβ CAR T cells lysed mature CD14(+) monocytes, while HSC colony formation was unaffected. Because of the potential for elimination of mature myeloid lineage, mRNA CAR electroporation for transient CAR expression was evaluated. mRNA-electroporated HA-FRβ CAR T cells retained effective antitumor activity in vitro and in vivo. Together, our results highlight the importance of antibody affinity in target protein detection and CAR development and suggest that transient delivery of potent HA-FRβ CAR T cells is highly effective against AML and reduces the risk for long-term myeloid toxicity. PMID:26898190

  17. Hematopoietic stem cell transplantation in China: current status and prospects

    PubMed Central

    Huang, Xiao-Jun

    2011-01-01

    During the past four decades, a substantial progress has been made in the field of hematopoietic stem cell transplantation (HSCT). From July, 2007 to December, 2010, a transplant survey from 42 HSCT units indicates that the types of transplantation performed are related identical (43%), related mismatched/haploidentical (28%), unrelated donor matched (11%), unrelated donor mismatched (7%), umbilical cord blood (UCB, 2%) and autologous (9%). The distribution of disease entities being transplanted in allogeneic settings is acute myeloid leukemia (AML) (34%), acute lymphoblastic leukemia(ALL) (24%), chronic myeloid leukemia (CML) (20%), myelodysplastic syndrome (MDS) (8%), aplastic anemia (AA) (7%), Mediterranean anemia (MIA) (2%), non-Hodgkin's lymphoma (NHL) (3%), and other diseases (3%). Clinical data from Peking University Institute of Hematology and other transplant centers suggest that haploidentical transplantation has been a choice of the best alternative source of stem cells for individual patients without matched sibling donors. A modified donor lymphocyte infusion (DLI) approach can be safely used for prophylaxis and treatment of leukemia relapse in patients with advanced leukemia following mismatched transplant. The number of transplants from unrelated donor or related mismatched/haploidentical donor has increased significantly during recent years. Double UCBT is a promising strategy for the therapy of hematological disease. In addition, mesenchymal stem cell (MSC) transplantation may be a potential therapeutic approach for treating systemic lupus erythematosus (SLE). PMID:22432069

  18. Myeloid sarcoma presenting as a colon polyp and harbinger of chronic myelogenous leukemia

    PubMed Central

    Rogers, Robert; Ettel, Mark; Cho, Margaret; Chan, Alexander; Wu, Xiao-Jun; Neto, Antonio G

    2016-01-01

    Myeloid sarcoma, also known as granulocytic sarcoma or chloroma is an unusual accumulation of malignant myeloid precursor cells in an extramedullary site, which disrupts the normal architecture of the involved tissue. It is known to occur more commonly in patients with acute myelogenous leukemia and less commonly in those with myelodysplastic syndrome and myeloproliferative neoplasm, such as chronic myelogenous leukemia. The most common sites of involvement include bone, skin and lymph nodes. However, rare cases have been reported in the gastrointestinal tract, genitourinary tract, or breast. Most commonly, a neoplastic extramedullary proliferation of myeloid precursors in a patient would have systemic involvement of a myeloid neoplasm, including in the bone marrow and peripheral blood. Infrequently, extramedullary disease may be the only site of involvement. It may also occur as a localized antecedent to more generalized disease or as a site of recurrence. Herein, we present the first case in the English literature of a patient presenting with an isolated site of myeloid sarcoma arising in the form of a colonic polyp which, after subsequent bone marrow biopsy, was found to be a harbinger of chronic myelogenous leukemia. PMID:26989468

  19. Hematopoietic bone marrow recovery after radiation therapy: MRI evaluation

    SciTech Connect

    Casamassima, F.; Ruggiero, C.; Caramella, D.; Tinacci, E.; Villari, N.; Ruggiero, M. )

    1989-05-01

    Magnetic resonance imaging (MRI) is able to detect the increase of adipocytes in the hematopoietic bone marrow that occurs as a consequence of radiotherapy and is indicative of the loss of myeloid tissue. By monitoring this process, it is also possible to determine the recovery of the bone marrow. The amount of viable hematopoietic tissue plays a fundamental role in determining whether the patient is able to undergo further antineoplastic therapy, particularly chemotherapy. We examined 35 patients who had been treated with radiotherapy for Hodgkin's lymphoma (12), uterine cervix carcinoma (nine), ovarian dysgerminoma (six), testicular seminoma (four), and non-Hodgkin's lymphoma (four). We observed that radiation-induced modifications of the MRI pattern in the bone marrow are tightly linked to two parameters; the administered radiation dose and the length of time passed after the treatment. Bone marrow recovery was observed only when patients were treated with doses lower than 50 Gy. The earlier radiation-induced modifications of the bone marrow MRI pattern occurred 6 to 12 months after irradiation, and they were most evident 5 to 6 years after the treatment. From 2 to 9 years after radiotherapy, we observed partial recovery. Complete recovery, when it occurred, was observed only 10 to 23 years after the treatment. Our results indicate that MRI studies are likely to be useful in the assessment of radiation-induced injuries.

  20. Hematopoietic Neoplasias in Horses: Myeloproliferative and Lymphoproliferative Disorders

    PubMed Central

    MUÑOZ, Ana; RIBER, Cristina; TRIGO, Pablo; CASTEJÓN, Francisco

    2010-01-01

    Leukemia, i.e., the neoplasia of one or more cell lines of the bone marrow, although less common than in other species, it is also reported in horses. Leukemia can be classified according to the affected cells (myeloproliferative or lymphoproliferative disorders), evolution of clinical signs (acute or chronic) and the presence or lack of abnormal cells in peripheral blood (leukemic, subleukemic and aleukemic leukemia). The main myeloproliferative disorders in horses are malignant histiocytosis and myeloid leukemia, the latter being classified as monocytic and myelomonocytic, granulocytic, primary erythrocytosis or polycythemia vera and megakaryocytic leukemia. The most common lymphoproliferative disorders in horses are lymphoid leukemia, plasma cell or multiple myeloma and lymphoma. Lymphoma is the most common hematopoietic neoplasia in horses and usually involves lymphoid organs, without leukemia, although bone marrow may be affected after metastasis. Lymphoma could be classified according to the organs involved and four main clinical categories have been established: generalized-multicentric, alimentary-gastrointestinal, mediastinal-thymic-thoracic and cutaneous. The clinical signs, hematological and clinical pathological findings, results of bone marrow aspirates, involvement of other organs, prognosis and treatment, if applicable, are presented for each type of neoplasia. This paper aims to provide a guide for equine practitioners when approaching to clinical cases with suspicion of hematopoietic neoplasia. PMID:24833969

  1. Mll5 contributes to hematopoietic stem cell fitness and homeostasis

    PubMed Central

    Zhang, Yan; Wong, Jasmine; Klinger, Mark; Tran, Mary T.; Shannon, Kevin M.

    2009-01-01

    MLL5 is a novel trithorax group gene and a candidate tumor suppressor gene located within a 2.5-Mb interval of chromosome band 7q22 that frequently is deleted in human myeloid malignancy. Here we show that inactivation of the Mll5 gene in mice results in a 30% reduction in the average representation of hematopoietic stem cells and in functional impairment of long-term hematopoietic repopulation potential under competitive conditions. Bone marrow cells from Mll5-deficient mice were defective in spleen colony-forming assays, and the mutant mice showed enhanced susceptibility to 5-fluorouracil–induced myelosuppression. Heterozygous and homozygous Mll5 mutant mice did not spontaneously develop hematologic cancers, and loss of Mll5 did not alter the phenotype of a fatal myeloproliferative disorder induced by oncogenic Kras in vivo. Collectively, the data reveal an important role for Mll5 in HSC homeostasis and provide a basis for further studies to explore its role in leukemogenesis. PMID:18818388

  2. Vosaroxin and Infusional Cytarabine in Treating Patients With Untreated Acute Myeloid Leukemia

    ClinicalTrials.gov

    2016-03-10

    Acute Myeloid Leukemia; Acute Myeloid Leukemia Arising From Previous Myelodysplastic Syndrome; Acute Myeloid Leukemia With Multilineage Dysplasia; Myeloid Sarcoma; Secondary Acute Myeloid Leukemia; Therapy-Related Acute Myeloid Leukemia; Therapy-Related Myelodysplastic Syndrome

  3. Ophthalmic Manifestations of Hematopoietic Malignancy.

    PubMed

    Yoshida-Hata, Natsuyo; Katai, Naomichi; Oshitari, Toshiyuki

    2016-01-01

    Purpose. To report the ocular findings in patients with hematopoietic malignancy with optic nerve involvement and abducens nerve palsy. Methods. The medical records of all cases of hematopoietic cancer with ophthalmic involvements seen in the Department of Ophthalmology of the National Center for Global Health and Medicine between 2009 and 2014 were reviewed. Results. Eight patients with hematopoietic cancer with optic nerve invasion or abducens nerve palsy were studied. The primary diseases were 3 cases of multiple myeloma, 1 case of acute lymphocytic leukemia, 1 case of follicular lymphoma, and 3 cases of AIDS-related lymphoma. Six cases had optic nerve invasion, 2 cases had abducens nerve palsy, and 1 case had optic nerve invasion of both eyes. The median visual acuity of eyes with optic nerve invasion was 0.885 logarithm of the minimum angle of resolution (logMAR) units. The final visual acuity of eyes with optic nerve invasion was 1.25 logMAR units, and that of those with sixth-nerve palsy was -0.1 logMAR units. Six cases died during the five-year follow-up period. An ophthalmic involvement in patients with hematopoietic cancer, especially AIDS-related lymphoma, was associated with poor prognosis. Conclusion. Because ophthalmic involvement in patients with hematopoietic malignancy has a poor prognosis, an early diagnosis of the cancers by the ophthalmologic findings by ophthalmologists could improve the prognosis. PMID:27375913

  4. Ophthalmic Manifestations of Hematopoietic Malignancy

    PubMed Central

    2016-01-01

    Purpose. To report the ocular findings in patients with hematopoietic malignancy with optic nerve involvement and abducens nerve palsy. Methods. The medical records of all cases of hematopoietic cancer with ophthalmic involvements seen in the Department of Ophthalmology of the National Center for Global Health and Medicine between 2009 and 2014 were reviewed. Results. Eight patients with hematopoietic cancer with optic nerve invasion or abducens nerve palsy were studied. The primary diseases were 3 cases of multiple myeloma, 1 case of acute lymphocytic leukemia, 1 case of follicular lymphoma, and 3 cases of AIDS-related lymphoma. Six cases had optic nerve invasion, 2 cases had abducens nerve palsy, and 1 case had optic nerve invasion of both eyes. The median visual acuity of eyes with optic nerve invasion was 0.885 logarithm of the minimum angle of resolution (logMAR) units. The final visual acuity of eyes with optic nerve invasion was 1.25 logMAR units, and that of those with sixth-nerve palsy was −0.1 logMAR units. Six cases died during the five-year follow-up period. An ophthalmic involvement in patients with hematopoietic cancer, especially AIDS-related lymphoma, was associated with poor prognosis. Conclusion. Because ophthalmic involvement in patients with hematopoietic malignancy has a poor prognosis, an early diagnosis of the cancers by the ophthalmologic findings by ophthalmologists could improve the prognosis. PMID:27375913

  5. Signaling pathways implicated in hematopoietic progenitor cell proliferation and differentiation.

    PubMed

    Bugarski, Diana; Krstic, Aleksandra; Mojsilovic, Slavko; Vlaski, Marija; Petakov, Marijana; Jovcic, Gordana; Stojanovic, Nevenka; Milenkovic, Pavle

    2007-01-01

    The objective of this study was to investigate the signal transduction pathways associated with the clonal development of myeloid and erythroid progenitor cells. The contribution of particular signaling molecules of protein tyrosine kinases (PTKs), mitogen-activated protein (MAP) kinase, and PI-3 kinase signaling to the growth of murine bone marrow colony forming unit-granulocyte-macrophage (CFU-GM) and erythroid (burst forming unit-erythroid [BFU-E] and colony forming unit-erythroid [CFU-E]) progenitors was examined in studies performed in the presence or absence of specific signal transduction inhibitors. The results clearly pointed to different signal transducing intermediates that are involved in cell proliferation and differentiation depending on the cell lineage, as well as on the progenitors' maturity. Lineage-specific differences were obtained when chemical inhibitors specific for receptor- or nonreceptor-PTKs, as well as for the main groups of distinctly regulated MAPK cascades, were used because all of these compounds suppressed the growth of erythroid progenitors, with no major effects on myeloid progenitors. At the same time, differential involvement of MEK/extracellular signal-regulated kinase (ERK) MAPK transduction pathway was observed in the proliferation and/or differentiation of early, BFU-E, and late, CFU-E, erythroid progenitor cells. The results also demonstrated that phosphatydylinositol (PI)-3 kinase and nuclear factor kappaB (NF-kappaB) transcriptional factor were required for maintenance of both myeloid and erythroid progenitor cell function. Overall, the data obtained indicated that committed hematopoietic progenitors express a certain level of constitutive signaling activity that participates in the regulation of normal steady-state hematopoiesis and point to the importance of evaluating the impact of signal transduction inhibitors on normal bone marrow when used as potential therapeutic agents. PMID:17202596

  6. Systems biological analyses reveal the HCV-specific regulation of hematopoietic development

    PubMed Central

    Velazquez, Victoria M.; Uebelhoer, Luke S.; Thapa, Manoj; Ibegbu, Chris; Courtney, Cynthia; Bosinger, Steven E.; Magliocca, Joseph F.; Adams, Andrew B.; Kirk, Allan D.; Knechtle, Stuart J.; Kalman, Daniel; Suthar, Mehul; Grakoui, Arash

    2014-01-01

    Chronic liver disease is characterized by the liver enrichment of myeloid DCs. To assess the role of disease on myelopoiesis, we utilized a systems biology approach to study development in liver-resident cells expressing stem cell marker CD34. In patients with end-stage liver disease, liver CD34+ cells were comprised by two subsets, designated CD34+CD146+ and CD34+CD146−, and hematopoietic function was restricted to CD34+CD146− cells. Liver CD34 frequencies were reduced during nonalcoholic steatohepatitis (NASH) and chronic hepatitis C virus (HCV) compared to alcohol liver disease (ALD), and this reduction correlated with viral load in the HCV cohort. To better understand the relationship between liver CD34+CD146+ and CD34+CD146− subsets and any effects of disease on CD34 development, we used gene expression profiling and computational modeling to compare each subset during ALD and HCV. For CD34+CD146+ cells, increased expression of endothelial cell genes including von Willebrand factor, VE-cadherin and eNOS were observed when compared to CD34+CD146− cells, and minimal effects of ALD and HCV diseases on gene expression were observed. Importantly for CD34+CD146− cells, chronic HCV was associated with a distinct ‘imprint’ of programs related to cell cycle, DNA repair, chemotaxis, development, and activation, with an emphasis on myeloid and B lymphocyte lineages. This HCV signature was further translated in side-by-side analyses, where HCV CD34+CD146− cells demonstrated superior hematopoietic growth, colony formation, and diversification compared to ALD and NASH when cultured identically. Disease-associated effects on hematopoiesis were also evident by phenotypic alterations in the expression of CD14, HLA-DR and CD16 by myeloid progeny cells. Conclusion Etiology drives progenitor fate within diseased tissues. The liver may be a useful source of hematopoietic cells for therapy, or as therapeutic targets. PMID:25331524

  7. c-kit mRNA expression in human and murine hematopoietic cell lines.

    PubMed

    André, C; d'Auriol, L; Lacombe, C; Gisselbrecht, S; Galibert, F

    1989-08-01

    The c-kit proto-oncogene belongs to the tyrosine kinase receptor family. Although its ligand is still unknown, there is increasing evidence to suggest its involvement in hematopoiesis. In order to detect lineage or differentiation related specificity, we have studied c-kit mRNA expression in both human and murine hematopoietic organs and cell lines. We show that c-kit mRNA expression is found at early stages of erythroid and myeloid differentiation. There is however, no evidence of c-kit expression in the lymphoid lineage. Our results suggest a possible role for c-kit as a receptor in the early stages of the erythroid/myeloid differentiation. PMID:2474787

  8. Acute myeloid leukemia in children: Current status and future directions.

    PubMed

    Taga, Takashi; Tomizawa, Daisuke; Takahashi, Hiroyuki; Adachi, Souichi

    2016-02-01

    Acute myeloid leukemia (AML) accounts for 25% of pediatric leukemia and affects approximately 180 patients annually in Japan. The treatment outcome for pediatric AML has improved through advances in chemotherapy, hematopoietic stem cell transplantation (HSCT), supportive care, and optimal risk stratification. Currently, clinical pediatric AML studies are conducted separately according to the AML subtypes: de novo AML, acute promyelocytic leukemia (APL), and myeloid leukemia with Down syndrome (ML-DS). Children with de novo AML are treated mainly with anthracyclines and cytarabine, in some cases with HSCT, and the overall survival (OS) rate now approaches 70%. Children with APL are treated with an all-trans retinoic acid (ATRA)-combined regimen with an 80-90% OS. Children with ML-DS are treated with a less intensive regimen compared with non-DS patients, and the OS is approximately 80%. HSCT in first remission is restricted to children with high-risk de novo AML only. To further improve outcomes, it will be necessary to combine more accurate risk stratification strategies using molecular genetic analysis with assessment of minimum residual disease, and the introduction of new drugs in international collaborative clinical trials. PMID:26645706

  9. Complete response of myeloid sarcoma with cardiac involvement to radiotherapy.

    PubMed

    Yang, Wen-Chi; Yao, Ming; Chen, Yu-Hsuan; Kuo, Sung-Hsin

    2016-06-01

    We present a rare case of intracardiac myeloid sarcoma (MS) of acute myeloid leukemia (AML) and who responds completely well to low-dose radiotherapy. This 19-year-old young man initially presented with AML and received standard chemotherapy followed by allogeneic hematopoietic stem cell transplantation (HSCT). However, he developed intracardiac isolated MS relapse with the presentation of exertional dyspnea and superior vena cava (SVC) syndrome 3 years later. He then received radiotherapy with 24 Gy at a 12 daily fractions using forward "field in field" intensity modulated radiotherapy technique. He dramatically had improved clinical symptoms, and complete remission was achieved one month after completing radiotherapy. Our result is in line with anecdotal case reports showed that radiotherapy with 15 Gy in 10 fractions or with 24 Gy in 12 fractions resulted in good response and less toxicity of 2 cases of MS with cardiac involvement. These results indicate that a modest radiotherapy dose, 24 Gy, achieves good local control of MS with cardiac involvement. PMID:27293853

  10. Complete response of myeloid sarcoma with cardiac involvement to radiotherapy

    PubMed Central

    Yang, Wen-Chi; Yao, Ming; Chen, Yu-Hsuan

    2016-01-01

    We present a rare case of intracardiac myeloid sarcoma (MS) of acute myeloid leukemia (AML) and who responds completely well to low-dose radiotherapy. This 19-year-old young man initially presented with AML and received standard chemotherapy followed by allogeneic hematopoietic stem cell transplantation (HSCT). However, he developed intracardiac isolated MS relapse with the presentation of exertional dyspnea and superior vena cava (SVC) syndrome 3 years later. He then received radiotherapy with 24 Gy at a 12 daily fractions using forward “field in field” intensity modulated radiotherapy technique. He dramatically had improved clinical symptoms, and complete remission was achieved one month after completing radiotherapy. Our result is in line with anecdotal case reports showed that radiotherapy with 15 Gy in 10 fractions or with 24 Gy in 12 fractions resulted in good response and less toxicity of 2 cases of MS with cardiac involvement. These results indicate that a modest radiotherapy dose, 24 Gy, achieves good local control of MS with cardiac involvement. PMID:27293853

  11. General Information about Adult Acute Myeloid Leukemia

    MedlinePlus

    ... Acute Myeloid Leukemia Treatment (PDQ®)–Patient Version General Information About Adult Acute Myeloid Leukemia Go to Health ... the PDQ Adult Treatment Editorial Board . Clinical Trial Information A clinical trial is a study to answer ...

  12. Treatment Options for Adult Acute Myeloid Leukemia

    MedlinePlus

    ... Treatment Childhood AML Treatment Research Adult Acute Myeloid Leukemia Treatment (PDQ®)–Patient Version General Information About Adult Acute Myeloid Leukemia Go to Health Professional Version Key Points Adult ...

  13. Stages of Adult Acute Myeloid Leukemia

    MedlinePlus

    ... Treatment Childhood AML Treatment Research Adult Acute Myeloid Leukemia Treatment (PDQ®)–Patient Version General Information About Adult Acute Myeloid Leukemia Go to Health Professional Version Key Points Adult ...

  14. Treatment Option Overview (Adult Acute Myeloid Leukemia)

    MedlinePlus

    ... Treatment Childhood AML Treatment Research Adult Acute Myeloid Leukemia Treatment (PDQ®)–Patient Version General Information About Adult Acute Myeloid Leukemia Go to Health Professional Version Key Points Adult ...

  15. Identifying States along the Hematopoietic Stem Cell Differentiation Hierarchy with Single Cell Specificity via Raman Spectroscopy.

    PubMed

    Ilin, Yelena; Choi, Ji Sun; Harley, Brendan A C; Kraft, Mary L

    2015-11-17

    A major challenge for expanding specific types of hematopoietic cells ex vivo for the treatment of blood cell pathologies is identifying the combinations of cellular and matrix cues that direct hematopoietic stem cells (HSC) to self-renew or differentiate into cell populations ex vivo. Microscale screening platforms enable minimizing the number of rare HSCs required to screen the effects of numerous cues on HSC fate decisions. These platforms create a strong demand for label-free methods that accurately identify the fate decisions of individual hematopoietic cells at specific locations on the platform. We demonstrate the capacity to identify discrete cells along the HSC differentiation hierarchy via multivariate analysis of Raman spectra. Notably, cell state identification is accurate for individual cells and independent of the biophysical properties of the functionalized polyacrylamide gels upon which these cells are cultured. We report partial least-squares discriminant analysis (PLS-DA) models of single cell Raman spectra enable identifying four dissimilar hematopoietic cell populations across the HSC lineage specification. Successful discrimination was obtained for a population enriched for long-term repopulating HSCs (LT-HSCs) versus their more differentiated progeny, including closely related short-term repopulating HSCs (ST-HSCs) and fully differentiated lymphoid (B cells) and myeloid (granulocytes) cells. The lineage-specific differentiation states of cells from these four subpopulations were accurately identified independent of the stiffness of the underlying biomaterial substrate, indicating subtle spectral variations that discriminated these populations were not masked by features from the culture substrate. This approach enables identifying the lineage-specific differentiation stages of hematopoietic cells on biomaterial substrates of differing composition and may facilitate correlating hematopoietic cell fate decisions with the extrinsic cues that

  16. Stem Cell Modeling of Core Binding Factor Acute Myeloid Leukemia

    PubMed Central

    Mosna, Federico

    2016-01-01

    Even though clonally originated from a single cell, acute leukemia loses its homogeneity soon and presents at clinical diagnosis as a hierarchy of cells endowed with different functions, of which only a minority possesses the ability to recapitulate the disease. Due to their analogy to hematopoietic stem cells, these cells have been named “leukemia stem cells,” and are thought to be chiefly responsible for disease relapse and ultimate survival after chemotherapy. Core Binding Factor (CBF) Acute Myeloid Leukemia (AML) is cytogenetically characterized by either the t(8;21) or the inv(16)/t(16;16) chromosomal abnormalities, which, although being pathognomonic, are not sufficient per se to induce overt leukemia but rather determine a preclinical phase of disease when preleukemic subclones compete until the acquisition of clonal dominance by one of them. In this review we summarize the concepts regarding the application of the “leukemia stem cell” theory to the development of CBF AML; we will analyze the studies investigating the leukemogenetic role of t(8;21) and inv(16)/t(16;16), the proposed theories of its clonal evolution, and the role played by the hematopoietic niches in preserving the disease. Finally, we will discuss the clinical implications of stem cell modeling of CBF AML for the therapy of the disease. PMID:26880987

  17. Secondary solid cancers after allogeneic hematopoietic cell transplantation using busulfan-cyclophosphamide conditioning

    PubMed Central

    Brazauskas, Ruta; Rizzo, J. Douglas; Sobecks, Ronald M.; Wang, Zhiwei; Horowitz, Mary M.; Bolwell, Brian; Wingard, John R.; Socie, Gerard

    2011-01-01

    Risks of secondary solid cancers among allogeneic hematopoietic cell transplant (HCT) recipients who receive conditioning without total body irradiation are not well known. We evaluated the incidence and risk factors for solid cancers after HCT using high-dose busulfan-cyclophosphamide conditioning in 4318 recipients of first allogeneic HCT for acute myeloid leukemia in first complete remission (N = 1742) and chronic myeloid leukemia in first chronic phase (N = 2576). Our cohort represented 22 041 person-years at risk. Sixty-six solid cancers were reported at a median of 6 years after HCT. The cumulative-incidence of solid cancers at 5 and 10 years after HCT was 0.6% and 1.2% among acute myeloid leukemia and 0.9% and 2.4% among chronic myeloid leukemia patients. In comparison to general population incidence rates, HCT recipients had 1.4× higher than expected rate of invasive solid cancers (95% confidence interval, 1.08-1.79, P = .01). Significantly elevated risks were observed for tumors of the oral cavity, esophagus, lung, soft tissue, and brain. Chronic graft-versus-host disease was an independent risk factor for all solid cancers, and especially cancers of the oral cavity. Recipients of allogeneic HCT using busulfan-cyclophosphamide conditioning are at risk for developing solid cancers. Their incidence continues to increase with time, and lifelong cancer surveillance is warranted in this population. PMID:20926773

  18. Myeloid leukemia after hematotoxins.

    PubMed Central

    Larson, R A; LeBeau, M M; Vardiman, J W; Rowley, J D

    1996-01-01

    One of the most serious consequences of cancer therapy is the development of a second cancer, especially leukemia. Several distinct subsets of therapy-related leukemia can now be distinguished. Classic therapy-related myeloid leukemia typically occurs 5 to 7 years after exposure to alkylating agents and/or irradiation, has a myelodysplastic phase with trilineage involvement, and is characterized by abnormalities of the long arms of chromosomes 5 and/or 7. Response to treatment is poor, and allogenic bone marrow transplantation is recommended. Leukemia following treatment with agents that inhibit topoisomerase II, however, has a shorter latency, no preleukemic phase, a monoblastic, myelomonocytic, or myeloblastic phenotype, and balanced translocations, most commonly involving chromosome bands 11q23 or 21q22. The MLL gene at 11q23 or the AML1 gene at 21q22 are almost uniformly rearranged. MLL is involved with many fusion gene partners. Therapy-related acute lymphoblastic leukemia also occurs with 11q23 rearrangements. Therapy-related leukemias with 11q23 or 21q22 rearrangements, inv(16) or t(15;17), have a more favorable response to treatment and a clinical course similar to their de novo counterparts. PMID:9118910

  19. Myeloid leukemia after hematotoxins

    SciTech Connect

    Larson, R.A.; LeBeau, M.M.; Vardiman, J.W.; Rowley, J.D.

    1996-12-01

    One of the most serious consequences of cancer therapy is the development of a second cancer, especially leukemia. Several distinct subsets of therapy-related leukemia can now be distinguished. Classic therapy-related myeloid leukemia typically occurs 5 to 7 years after exposure to alkylating agents and/or irradiation, has a myelodysplastic phase with trilineage involvement, and is characterized by abnormalities of the long arms of chromosomes 5 and/or 7. Response to treatment is poor, and allogeneic bone marrow transplantation is recommended. Leukemia following treatment with agents that inhibit topoisomerase 11, however, has a shorter latency, no preleukemic phase, a monoblastic, myelomonocytic, or myeloblastic phenotype, and balanced translocations, most commonly involving chromosome bands 11 q23 or 21 q22. The MLL gene at 11 q23 or the AML1 gene at 21 q22 are almost uniformly rearranged. MLL is involved with many fusion gene partners. Therapy-related acute lymphoblastic leukemia also occurs with 1 1 q23 rearrangements. Therapy-related leukemias with 11 q23 or 21 q22 rearrangements, inv(16) or t(15;17), have a more favorable response to treatment and a clinical course similar to their de novo counterparts. 32 refs., 4 tabs.

  20. Omental sclerosing extramedullary hematopoietic tumors in Janus kinase-2 negative myelofibrosis: caveat at frozen section.

    PubMed

    Shinde, Sweety V; Shenoy, Asha S; Balsarkar, Dharmesh J; Shah, Vinaya B

    2014-01-01

    Sclerosing extramedullary hematopoietic tumors (SEMHTs) are associated with chronic myeloproliferative neoplasms. These extremely rare mass lesions were first described in kidney and peritoneum. On histopathology, they are characterized by sclerosis, entrapped fat, atypical megakaryocytes with myeloid and erythroid elements. Only approximately ten cases have been subsequently reported in orbit, lacrimal system, liver, omentum, and skin. The authors present a case of SEMHTs as incidentally detected omental nodules, while the patient was undergoing splenectomy for Janus kinase-2 negative myelofibrosis. The authors postulate their origin in omentum-associated lymphoid tissue; and highlight the diagnostic dilemma presented by SEMHTs at frozen section. PMID:25118752

  1. Flotillins Are Involved in the Polarization of Primitive and Mature Hematopoietic Cells

    PubMed Central

    Rajendran, Lawrence; Beckmann, Julia; Magenau, Astrid; Boneberg, Eva-Maria; Gaus, Katharina; Viola, Antonella; Giebel, Bernd; Illges, Harald

    2009-01-01

    Background Migration of mature and immature leukocytes in response to chemokines is not only essential during inflammation and host defense, but also during development of the hematopoietic system. Many molecules implicated in migratory polarity show uniform cellular distribution under non-activated conditions, but acquire a polarized localization upon exposure to migratory cues. Methodology/Principal Findings Here, we present evidence that raft-associated endocytic proteins (flotillins) are pre-assembled in lymphoid, myeloid and primitive hematopoietic cells and accumulate in the uropod during migration. Furthermore, flotillins display a polarized distribution during immunological synapse formation. Employing the membrane lipid-order sensitive probe Laurdan, we show that flotillin accumulation in the immunological synapse is concomittant with membrane ordering in these regions. Conclusions Together with the observation that flotillin polarization does not occur in other polarized cell types such as polarized epithelial cells, our results suggest a specific role for flotillins in hematopoietic cell polarization. Based on our results, we propose that in hematopoietic cells, flotillins provide intrinsic cues that govern segregation of certain microdomain-associated molecules during immune cell polarization. PMID:20027317

  2. 8-Chloro-Adenosine in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia

    ClinicalTrials.gov

    2016-05-11

    Recurrent Adult Acute Myeloid Leukemia; Relapsed Adult Acute Myeloid Leukemia; Acute Myeloid Leukemia Arising From Previous Myelodysplastic Syndrome; Acute Myeloid Leukemia Arising From Previous Myeloproliferative Disorder

  3. [Research Progress on the Role of Chromatin Remodeling Factor BRG1 in Acute Myeloid Leukemia].

    PubMed

    Gao, Shuo; Xu, Xue-Jing; Zhang, Kui

    2016-06-01

    BRG1 (Brahma-related gene 1, BRG1) is the ATPase subunit of SWI/SNF chromatin remodeling complexes, which plays an important role in cell cycle regulation, DNA repair and tumor development. Unlike the evidence as tumor suppressor genes in the past reports, latest researches show that BRG1 plays an important role in sustaining the growth of leukemia cells in acute myeloid leukemia, and these effects on normal hematopoietic stem cells are dispensable. Further studies of the role and mechanism of BRG1 in acute myeloid leukemia will contribute to the development of a new and promising targeted therapy strategy. This article reviews the role of BRG1 on leukemia cells and leukemia stem cells in AML and discusses the related mechanism, which providing some reference for the targeted treatment strategy of AML. PMID:27342536

  4. A 54-Year-Old Woman with Donor Cell Origin of Multiple Myeloma after Allogeneic Hematopoietic Stem Cell Transplantation for the Treatment of CML

    PubMed Central

    Maestas, Erika; Jain, Shikha; Stiff, Patrick

    2016-01-01

    Chronic myeloid leukemia is a myeloproliferative disorder that may be treated with hematopoietic stem cell transplantation (HSCT). While posttransplantation relapse of disease resulting from a failure to eradicate the patient's original leukemia could occur, patients may also rarely develop a secondary malignancy or myelodysplastic syndrome (MDS) of donor origin termed donor cell leukemia (DCL). Cases of donor-derived acute myeloid leukemia (AML) or MDS after HSCT or solid tumor transplantation have been published. However, very few cases of donor-derived multiple myeloma (MM) exist. We describe a patient who developed a donor-derived MM following allogeneic HSCT from a sibling donor. PMID:26989529

  5. Hematopoietic stem cells: multiparameter regulation.

    PubMed

    Song, Kedong; Li, Liying; Wang, Yiwei; Liu, Tianqing

    2016-04-01

    Hematopoietic stem cells (HSCs) are capable to self-renew with multi-potency which generated much excitement in clinical therapy. However, the main obstacle of HSCs in clinical application was insufficient number of HSCs which were derived from either bone marrow, peripheral blood or umbilical cord blood. This review briefly discusses the indispensable utility of growth factors and cytokines, stromal cells, extracellular matrix, bionic scaffold and microenvironment aiming to control the hematopoiesis in all directions and provide a better and comprehensive understanding for in vitro expansion of hematopoietic stem cells. PMID:26883144

  6. Diagnosing and managing advanced chronic myeloid leukemia.

    PubMed

    Deininger, Michael W

    2015-01-01

    Clinical staging of chronic myeloid leukemia (CML) distinguishes between chronic phase (CP-CML), accelerated phase (AP-CML), and blastic phase (BP-CML), reflecting its natural history in the absence of effective therapy. Morphologically, transformation from CP-CML to AP/BP-CML is characterized by a progressive or sudden loss of differentiation. Multiple different somatic mutations have been implicated in transformation from CP-CML to AP/BC-CML, but no characteristic mutation or combination of mutations have emerged. Gene expression profiles of AP-CML and BP-CML are similar, consistent with biphasic evolution at the molecular level. Gene expression of tyrosine kinase inhibitor (TKI)-resistant CP-CML and second CP-CML resemble AP/BP-CML, suggesting that morphology alone is a poor predictor of biologic behavior. At the clinical level, progression to AP/BP-CML or resistance to first-line TKI therapy distinguishes a good risk condition with survival close to the general population from a disease likely to reduce survival. Progression while receiving TKI therapy is frequently caused by mutations in the target kinase BCR-ABL1, but progression may occur in the absence of explanatory BCR-ABL1 mutations, suggesting involvement of alternative pathways. Identifying patients in whom milestones of TKI response fail to occur or whose disease progress while receiving therapy requires appropriate molecular monitoring. Selection of salvage TKI depends on prior TKI history, comorbidities, and BCR-ABL1 mutation status. Despite the introduction of novel TKIs, therapy of AP/BP-CML remains challenging and requires accepting modalities with substantial toxicity, such as hematopoietic stem cell transplantation (HSCT). PMID:25993200

  7. Multipotent hematopoietic cell lines derived from C/EBPalpha(-/-) knockout mice display granulocyte macrophage-colony-stimulating factor, granulocyte- colony-stimulating factor, and retinoic acid-induced granulocytic differentiation.

    PubMed

    Collins, S J; Ulmer, J; Purton, L E; Darlington, G

    2001-10-15

    The transcription factor C/EBPalpha is an important mediator of granulocyte differentiation and regulates the expression of multiple granulocyte-specific genes including the granulocyte-colony-stimulating factor (G-CSF) receptor, neutrophil elastase, and myeloperoxidase. Indeed C/EBPalpha knockout mice display a profound block in granulocyte differentiation. To study this block in granulocytic differentiation in more detail, retroviral vector-mediated transduction of a dominant-negative retinoic acid receptor was used to establish hematopoietic growth factor-dependent, lympho-myeloid progenitor cell lines from the fetal livers of both the C/EBPalpha knockout animals (C/EBPalpha(-/-)) and their heterozygous littermates (C/EBPalpha(+/-)). Surprisingly, the C/EBPalpha(-/-) cell lines displayed significant spontaneous granulocytic differentiation, and this differentiation was markedly enhanced when the cells were stimulated with granulocyte macrophage (GM)-CSF. This GM-CSF-mediated differentiation was associated with the up-regulation of G-CSF receptor mRNA, and the combination of GM-CSF and G-CSF generated more than 95% mature neutrophils in the C/EBPalpha(-/-) cultures. The addition of all-trans retinoic acid also enhanced this granulocytic differentiation of the cultured C/EBPalpha(-/-) cells, indicating that the activated retinoic acid receptors can enhance granulocytic differentiation through a molecular pathway that is independent of C/EBPalpha. These studies clearly indicate that terminal granulocytic differentiation associated with the up-regulation of C/EBPalpha-responsive genes can occur in the absence of C/EBPalpha, and they indicate the existence of multiple independent molecular pathways potentially used by primitive hematopoietic precursors that can lead to the development of mature granulocytes. PMID:11588034

  8. Essential role for telomerase in chronic myeloid leukemia induced by BCR-ABL in mice

    PubMed Central

    Vicente-Dueñas, Carolina; Barajas-Diego, Marcos; Romero-Camarero, Isabel; González-Herrero, Inés; Flores, Teresa; Sánchez-García, Isidro

    2012-01-01

    The telomerase protein is constitutively activated in malignant cells from many patients with cancer, including the chronic myeloid leukemia (CML), but whether telomerase is essential for the pathogenesis of this disease is not known. Here, we used telomerase deficient mice to determine the requirement for telomerase in CML induced by BCR-ABL in mouse models of CML. Loss of one telomerase allele or complete deletion of telomerase prevented the development of leukemia induced by BCR-ABL. However, BCR-ABL was expressed and active in telomerase heterozygous and null leukemic hematopoietic stem cells. These results demonstrate that telomerase is essential for oncogene-induced reprogramming of hematopoietic stem cells in CML development and validate telomerase and the genes it regulates as targets for therapy in CML. PMID:22408137

  9. Cancer-Associated Myeloid Regulatory Cells.

    PubMed

    De Vlaeminck, Yannick; González-Rascón, Anna; Goyvaerts, Cleo; Breckpot, Karine

    2016-01-01

    Myeloid cells are critically involved in the pathophysiology of cancers. In the tumor microenvironment (TME), they comprise tumor-associated macrophages (TAMs), neutrophils (TANs), dendritic cells, and myeloid-derived suppressor cells, which are further subdivided into a monocytic subset and a granulocytic subset. Some of these myeloid cells, in particular TAMs and TANs, are divided into type 1 or type 2 cells, according to the paradigm of T helper type 1 or type 2 cells. Type 1-activated cells are generally characterized as cells that aid tumor rejection, while all other myeloid cells are shown to favor tumor progression. Moreover, these cells are often at the basis of resistance to various therapies. Much research has been devoted to study the biology of myeloid cells. This endeavor has proven to be challenging, as the markers used to categorize myeloid cells in the TME are not restricted to particular subsets. Also from a functional and metabolic point of view, myeloid cells share many features. Finally, myeloid cells are endowed with a certain level of plasticity, which further complicates studying them outside their environment. In this article, we challenge the exclusive use of cell markers to unambiguously identify myeloid cell subsets in the TME. We further propose to divide myeloid cells into myeloid regulatory or stimulatory cells according to their pro- or antitumor function, because we contend that for therapeutic purposes it is not targeting the cell subsets but rather targeting their protumor traits; hence, myeloid regulatory cells will push antitumor immunotherapy to the next level. PMID:27065074

  10. Cancer-Associated Myeloid Regulatory Cells

    PubMed Central

    De Vlaeminck, Yannick; González-Rascón, Anna; Goyvaerts, Cleo; Breckpot, Karine

    2016-01-01

    Myeloid cells are critically involved in the pathophysiology of cancers. In the tumor microenvironment (TME), they comprise tumor-associated macrophages (TAMs), neutrophils (TANs), dendritic cells, and myeloid-derived suppressor cells, which are further subdivided into a monocytic subset and a granulocytic subset. Some of these myeloid cells, in particular TAMs and TANs, are divided into type 1 or type 2 cells, according to the paradigm of T helper type 1 or type 2 cells. Type 1-activated cells are generally characterized as cells that aid tumor rejection, while all other myeloid cells are shown to favor tumor progression. Moreover, these cells are often at the basis of resistance to various therapies. Much research has been devoted to study the biology of myeloid cells. This endeavor has proven to be challenging, as the markers used to categorize myeloid cells in the TME are not restricted to particular subsets. Also from a functional and metabolic point of view, myeloid cells share many features. Finally, myeloid cells are endowed with a certain level of plasticity, which further complicates studying them outside their environment. In this article, we challenge the exclusive use of cell markers to unambiguously identify myeloid cell subsets in the TME. We further propose to divide myeloid cells into myeloid regulatory or stimulatory cells according to their pro- or antitumor function, because we contend that for therapeutic purposes it is not targeting the cell subsets but rather targeting their protumor traits; hence, myeloid regulatory cells will push antitumor immunotherapy to the next level. PMID:27065074

  11. An autonomous CEBPA enhancer specific for myeloid-lineage priming and neutrophilic differentiation.

    PubMed

    Avellino, Roberto; Havermans, Marije; Erpelinck, Claudia; Sanders, Mathijs A; Hoogenboezem, Remco; van de Werken, Harmen J G; Rombouts, Elwin; van Lom, Kirsten; van Strien, Paulina M H; Gebhard, Claudia; Rehli, Michael; Pimanda, John; Beck, Dominik; Erkeland, Stefan; Kuiken, Thijs; de Looper, Hans; Gröschel, Stefan; Touw, Ivo; Bindels, Eric; Delwel, Ruud

    2016-06-16

    Neutrophilic differentiation is dependent on CCAAT enhancer-binding protein α (C/EBPα), a transcription factor expressed in multiple organs including the bone marrow. Using functional genomic technologies in combination with clustered regularly-interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 genome editing and in vivo mouse modeling, we show that CEBPA is located in a 170-kb topological-associated domain that contains 14 potential enhancers. Of these, 1 enhancer located +42 kb from CEBPA is active and engages with the CEBPA promoter in myeloid cells only. Germ line deletion of the homologous enhancer in mice in vivo reduces Cebpa levels exclusively in hematopoietic stem cells (HSCs) and myeloid-primed progenitor cells leading to severe defects in the granulocytic lineage, without affecting any other Cebpa-expressing organ studied. The enhancer-deleted progenitor cells lose their myeloid transcription program and are blocked in differentiation. Deletion of the enhancer also causes loss of HSC maintenance. We conclude that a single +42-kb enhancer is essential for CEBPA expression in myeloid cells only. PMID:26966090

  12. BMP signaling balances murine myeloid potential through SMAD-independent p38MAPK and NOTCH pathways.

    PubMed

    Cook, Brandoch D; Evans, Todd

    2014-07-17

    Bone morphogenetic protein (BMP) signaling regulates early hematopoietic development, proceeding from mesoderm patterning through the progressive commitment and differentiation of progenitor cells. The BMP pathway signals largely through receptor-mediated activation of Mothers Against Decapentaplegic homolog (SMAD) proteins, although alternate pathways are modulated through various components of mitogen-activated protein kinase (MAPK) signaling. Using a conditional, short hairpin RNA (shRNA)-based knockdown system in the context of differentiating embryonic stem cells (ESCs), we demonstrated previously that Smad1 promotes hemangioblast specification, but then subsequently restricts primitive progenitor potential. Here we show that co-knockdown of Smad5 restores normal progenitor potential of Smad1-depleted cells, suggesting opposing functions for Smad1 and Smad5. This balance was confirmed by cotargeting Smad1/5 with a specific chemical antagonist, LDN193189 (LDN). However, we discovered that LDN treatment after hemangioblast commitment enhanced primitive myeloid potential. Moreover, inhibition with LDN (but not SMAD depletion) increased expression of Delta-like ligands Dll1 and Dll3 and NOTCH activity; abrogation of NOTCH activity restored LDN-enhanced myeloid potential back to normal, corresponding with expression levels of the myeloid master regulator, C/EBPα. LDN but not SMAD activity was also associated with activation of the p38MAPK pathway, and blocking this pathway was sufficient to enhance myelopoiesis. Therefore, NOTCH and p38MAPK pathways balance primitive myeloid progenitor output downstream of the BMP pathway. PMID:24894772

  13. Therapeutically targeting SELF-reinforcing leukemic niches in acute myeloid leukemia: A worthy endeavor?

    PubMed

    Bernasconi, Paolo; Farina, Mirko; Boni, Marina; Dambruoso, Irene; Calvello, Celeste

    2016-05-01

    A tight relationship between the acute myeloid leukemia (AML) population and the bone marrow (BM) microenvironment has been convincingly established. The AML clone contains leukemic stem cells (LSCs) that compete with normal hematopoietic stem cells (HSCs) for niche occupancy and remodel the niche; whereas, the BM microenvironment might promote AML development and progression not only through hypoxia and homing/adhesion molecules, but also through genetic defects. Although it is still unknown whether the niche influences treatment results or contains any potential target for treatment, this dynamic AML-niche interaction might be a promising therapeutic objective to significantly improve the AML cure rate. PMID:26822317

  14. Germline duplication of ATG2B and GSKIP predisposes to familial myeloid malignancies.

    PubMed

    Saliba, Joseph; Saint-Martin, Cécile; Di Stefano, Antonio; Lenglet, Gaëlle; Marty, Caroline; Keren, Boris; Pasquier, Florence; Valle, Véronique Della; Secardin, Lise; Leroy, Gwendoline; Mahfoudhi, Emna; Grosjean, Sarah; Droin, Nathalie; Diop, M'boyba; Dessen, Philippe; Charrier, Sabine; Palazzo, Alberta; Merlevede, Jane; Meniane, Jean-Côme; Delaunay-Darivon, Christine; Fuseau, Pascal; Isnard, Françoise; Casadevall, Nicole; Solary, Eric; Debili, Najet; Bernard, Olivier A; Raslova, Hana; Najman, Albert; Vainchenker, William; Bellanné-Chantelot, Christine; Plo, Isabelle

    2015-10-01

    No major predisposition gene for familial myeloproliferative neoplasms (MPN) has been identified. Here we demonstrate that the autosomal dominant transmission of a 700-kb duplication in four genetically related families predisposes to myeloid malignancies, including MPN, frequently progressing to leukemia. Using induced pluripotent stem cells and primary cells, we demonstrate that overexpression of ATG2B and GSKIP enhances hematopoietic progenitor differentiation, including of megakaryocytes, by increasing progenitor sensitivity to thrombopoietin (TPO). ATG2B and GSKIP cooperate with acquired JAK2, MPL and CALR mutations during MPN development. Thus, the germline duplication may change the fitness of cells harboring signaling pathway mutations and increases the probability of disease development. PMID:26280900

  15. Acute myeloid leukemia.

    PubMed

    Appelbaum, F R; Rowe, J M; Radich, J; Dick, J E

    2001-01-01

    Through the hard work of a large number of investigators, the biology of acute myeloid leukemia (AML) is becoming increasingly well understood, and as a consequence, new therapeutic targets have been identified and new model systems have been developed for testing novel therapies. How these new therapies can be most effectively studied in the clinic and whether they will ultimately improve cure rates are questions of enormous importance. In this article, Dr. Jacob Rowe presents a summary of the current state-of-the-art therapy for adult AML. His contribution emphasizes the fact that AML is not a single disease, but a number of related diseases each distinguished by unique cytogenetic markers which in turn help determine the most appropriate treatment. Dr. Jerald Radich continues on this theme, emphasizing how these cytogenetic abnormalities, as well as other mutations, give rise to abnormal signal transduction and how these abnormal pathways may represent ideal targets for the development of new therapeutics. A third contribution by Dr. Frederick Appelbaum describes how AML might be made the target of immunologic attack. Specifically, strategies using antibody-based or cell-based immunotherapies are described including the use of unmodified antibodies, drug conjugates, radioimmunoconjugates, non-ablative allogeneic transplantation, T cell adoptive immunotherapy and AML vaccines. Finally, Dr. John Dick provides a review of the development of the NOD/SCID mouse model of human AML emphasizing both what it has taught us about the biology of the disease as well as how it can be used to test new therapies. Taken together, these reviews are meant to help us understand more about where we are in the treatment of AML, where we can go and how we might get there. PMID:11722979

  16. Gemtuzumab Ozogamicin in Treating Patients With Acute Myeloid Leukemia

    ClinicalTrials.gov

    2013-09-23

    Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Adult Acute Promyelocytic Leukemia (M3); Recurrent Adult Acute Myeloid Leukemia

  17. A fast and simple approach for the simultaneous detection of hematopoietic chimerism, NPM1, and FLT3-ITD mutations after allogeneic stem cell transplantation.

    PubMed

    Waterhouse, Miguel; Bertz, Hartmut; Finke, Juergen

    2014-02-01

    Hematopoietic chimerism can be used as a tool for patient management after allogeneic hematopoietic stem cell transplantation (HSCT). An increase in the proportion of recipient cells after transplantation is strongly associated with relapse in chronic myeloid leukemia. However, in acute myeloid leukemia (AML) the significance of increasing mixed chimerism (MC) as a predictive marker for relapse is less clear. Several mutations frequently found in AML have been employed for minimal residual disease detection and relapse prediction. Therefore, a combined analysis of hematopoietic chimerism and of the molecular aberrations found in AML could be used to improve MC characterization. We developed a multiplex PCR for use in the simultaneous detection of hematopoietic chimerism and mutations in nucleophosmin (NPM1) and fms-like tyrosine kinase-3 internal tandem duplication (FLT3-ITD). A total of 303 samples from 20 AML patients were analyzed after HSCT. The microsatellite markers used for hematopoietic chimerism detection were D1S80, D7S1517, D4S2366, THO1, and SE33. A total of 149 samples from 18 patients showed MC with a mean detection time of 9.7 months. From the 18 patients with MC, in 6 of the patients, no FLT3-ITD or NPM1 mutation was found at any time point tested, and these patients remained in complete hematological remission. In 12 patients with MC, FLT3-ITD and NPM1 mutations were found, and these patients showed signs of hematological relapse. Our combined analysis of NPM1/FLT3-ITD mutations and hematopoietic chimerism improved the characterization of patients with MC after HSCT. The present approach may be further expanded by combining additional mutations found in AML with hematopoietic chimerism detection. PMID:23907410

  18. Molecular Pathways: Myeloid Complicity in Cancer

    PubMed Central

    Stromnes, Ingunn M.; Greenberg, Philip D.; Hingorani, Sunil R.

    2014-01-01

    Cancer-induced inflammation results in accumulation of myeloid cells. It has become increasingly evident that tumor-dependent factors condition myeloid cells toward an immunosuppressive and pro-tumorigenic phenotype. These myeloid cells include progenitors and progeny of monocytes, granulocytes, macrophages, and dendritic cells. Myeloid cells are not simply bystanders in malignancy or barometers of disease burden. Reflecting their dynamic and plastic nature, myeloid cells manifesta continuum of cellular differentiation and are intimately involved at all stages of neoplastic progression. They can promote tumorigenesis through both immune-dependent and independent mechanisms and can dictate response to therapies. A greater understanding of the inherent plasticity and relationships among myeloid subsets is needed to inform therapeutic targeting. New clinical trials are being designed to modulate the activities of myeloid cells in cancer, which may be essential to maximize the efficacy of both conventional cytotoxic and immune-based therapies for solid tumors. PMID:25047706

  19. Adult neurogenesis in the decapod crustacean brain: A hematopoietic connection?

    PubMed Central

    Beltz, Barbara S.; Zhang, Yi; Benton, Jeanne L.; Sandeman, David C.

    2011-01-01

    New neurons are produced and integrated into circuits in the adult brains of many organisms, including crustaceans. In some crustacean species, the 1st- generation neuronal precursors reside in a niche exhibiting characteristics analogous to mammalian neurogenic niches. However, unlike mammalian niches where several generations of neuronal precursors coexist, the lineage of precursor cells in crayfish is spatially separated allowing the influence of environmental and endogenous regulators on specific generations in the neuronal precursor lineage to be defined. Experiments also demonstrate that the 1st-generation neuronal precursors in the crayfish Procambarus clarkii are not self-renewing. A source external to the neurogenic niche must therefore provide cells that replenish the 1st-generation precursor pool, because although these cells divide and produce a continuous efflux of 2nd-generation cells from the niche, the population of 1st-generation niche precursors is not diminished with growth and aging. In vitro studies show that cells extracted from the hemolymph, but not other tissues, are attracted to and incorporated into the neurogenic niche, a phenomenon that appears to involve serotonergic mechanisms. We propose that in crayfish, the hematopoietic system may be a source of cells that replenish the niche cell pool. These and other studies reviewed here establish decapod crustaceans as model systems in which the processes underlying adult neurogenesis, such as stem cell origins and transformation, can be readily explored. Studies in diverse species where adult neurogenesis occurs will result in a broader understanding of fundamental mechanisms and how evolutionary processes may have shaped the vertebrate/mammalian condition. PMID:21929622

  20. Phosphatase of regenerating liver in hematopoietic stem cells and hematological malignancies

    PubMed Central

    Kobayashi, Michihiro; Chen, Sisi; Gao, Rui; Bai, Yunpeng; Zhang, Zhong-Yin; Liu, Yan

    2014-01-01

    The phosphatases of regenerating liver (PRLs), consisting PRL1, PRL2 and PRL3, are dual-specificity protein phosphatases that have been implicated as biomarkers and therapeutic targets in several solid tumors. However, their roles in hematological malignancies are largely unknown. Recent findings demonstrate that PRL2 is important for hematopoietic stem cell self-renewal and proliferation. In addition, both PRL2 and PRL3 are highly expressed in some hematological malignancies, including acute myeloid leukemia (AML), chronic myeloid leukemia (CML), multiple myeloma (MM) and acute lymphoblastic leukemia (ALL). Moreover, PRL deficiency impairs the proliferation and survival of leukemia cells through regulating oncogenic signaling pathways. While PRLs are potential novel therapeutic targets in hematological malignancies, their exact biological function and cellular substrates remain unclear. This review will discuss how PRLs regulate hematopoietic stem cell behavior, what signaling pathways are regulated by PRLs, and how to target PRLs in hematological malignancies. An improved understanding of how PRLs function and how they are regulated may facilitate the development of PRL inhibitors that are effective in cancer treatment. PMID:25486470

  1. Dasatinib promotes the activation of quiescent hematopoietic stem cells in mice.

    PubMed

    Duyvestyn, Johanna M; Taylor, Samuel J; Dagger, Samantha A; Langdon, Wallace Y

    2016-05-01

    Dasatinib is an orally available broad-spectrum tyrosine kinase inhibitor that is widely used to treat chronic myeloid leukemia. It is also in clinical trials for the treatment of other malignancies, including solid tumors. Despite its wide use, little is known of its effects on normal hematopoietic stem and progenitor cells. Here, we study wild-type mice dosed with dasatinib and find that it causes the transient induction of proliferation of quiescent hematopoietic stem cells (HSCs). This finding was unexpected given the ability of dasatinib to inhibit c-Kit signaling and promote cell cycle arrest in many cell types. The transient induction of HSC proliferation in dasatinib-dosed mice coincided with a marked induction in the expression of Sca-1 and phospho-S6. Also evident at this time was a rapid but transient loss of lineage-committed hematopoietic progenitors that express high levels of c-Kit and the induction of stem cell factor in the serum. These findings suggest that activation of quiescent HSCs is part of a rapid rescue response that restores hematopoietic progenitors to pretreatment levels. This restoration coincides with HSCs returning to quiescence, and the expression of Sca-1 and phospho-S6 reverting to pre-treatment levels, even though dasatinib dosing is maintained. These data suggest that equilibrium is reached between the opposing forces of dasatinib and hematopoietic growth factors. The transient induction of HSC proliferation provided a window of opportunity whereby these cells became sensitive to killing by the cytotoxic drug 5-fluorouracil. PMID:26921649

  2. Spliceosomal component Sf3b1 is essential for hematopoietic differentiation in zebrafish.

    PubMed

    De La Garza, Adriana; Cameron, Rosannah C; Nik, Sara; Payne, Sara G; Bowman, Teresa V

    2016-09-01

    SF3B1 (Splicing factor 3b, subunit 1) is one of the most commonly mutated factors in myelodysplastic syndrome (MDS). Although the genetic correlation between SF3B1 mutations and MDS etiology are quite strong, no in vivo model currently exists to explore how SF3B1 loss alters blood cell development. Using zebrafish mutants, we show here that proper function of Sf3b1 is required for all hematopoietic lineages. As in MDS patients, zebrafish sf3b1 mutants develop a macrocytic-anemia-like phenotype due to a block in maturation at a late progenitor stage. The mutant embryos also develop neutropenia, because their primitive myeloid cells fail to mature and turn on differentiation markers such as l-plastin and myeloperoxidase. In contrast, production of definitive hematopoietic stem and progenitor cells (HSPCs) from hemogenic endothelial cells within the dorsal aorta is greatly diminished, whereas arterial endothelial cells are correctly fated. Notch signaling, imperative for the endothelial-to-hematopoietic transition, is also normal, indicating that HSPC induction is blocked in sf3b1 mutants downstream or independent of Notch signaling. The data demonstrate that Sf3b1 function is necessary during key differentiation fate decisions in multiple blood cell types. Zebrafish sf3b1 mutants offer a novel animal model with which to explore the role of splicing in hematopoietic development and provide an excellent in vivo system with which to delve into the question of why and how Sf3b1 dysfunction is detrimental to hematopoietic differentiation, which could improve MDS diagnosis and treatment. PMID:27260753

  3. Embryonic hematopoiesis in vertebrate somites gives rise to definitive hematopoietic stem cells.

    PubMed

    Qiu, Juhui; Fan, Xiaoying; Wang, Yixia; Jin, Hongbin; Song, Yixiao; Han, Yang; Huang, Shenghong; Meng, Yaping; Tang, Fuchou; Meng, Anming

    2016-08-01

    Hematopoietic stem cells (HSCs) replenish all types of blood cells. It is debating whether HSCs in adults solely originate from the aorta-gonad-mesonephros (AGM) region, more specifically, the dorsal aorta, during embryogenesis. Here, we report that somite hematopoiesis, a previously unwitnessed hematopoiesis, can generate definitive HSCs (dHSCs) in zebrafish. By transgenic lineage tracing, we found that a subset of cells within the forming somites emigrate ventromedially and mix with lateral plate mesoderm-derived primitive hematopoietic cells before the blood circulation starts. These somite-derived hematopoietic precursors and stem cells (sHPSCs) subsequently enter the circulation and colonize the kidney of larvae and adults. RNA-seq analysis reveals that sHPSCs express hematopoietic genes with sustained expression of many muscle/skeletal genes. Embryonic sHPSCs transplanted into wild-type embryos expand during growth and survive for life time with differentiation into various hematopoietic lineages, indicating self-renewal and multipotency features. Therefore, the embryonic origin of dHSCs in adults is not restricted to the AGM. PMID:27252540

  4. Role of Hematopoietic Stem Cells in Inflammation of the Pancreas during Diabetes Mellitus.

    PubMed

    Dygai, A M; Skurikhin, E G; Pershina, O V; Ermakova, N N; Krupin, V A; Ermolaeva, L A; Stakheeva, M N; Choinzonov, E L; Goldberg, V E; Reikhart, D V; Ellinidi, V N; Kravtsov, V Yu

    2016-02-01

    The model of streptozotocin-induced diabetes mellitus in C57Bl/6 mice was employed to study the role of precursors of insulin-producing β-cells, hematopoietic stem cells, and progenitor hematopoietic cells in inflammation. In addition to provoking hyperglycemia, streptozotocin elevated serum levels of IL-1β and hyaluronic acid, induced edema in the pancreatic insular tissue and its infiltration by inflammatory cells (neutrophils, lymphocytes, and macrophages) and fibroblasts. Inflammation in pancreatic islets was accompanied by necrotic processes and decreasing counts of multipotent progenitor β-cells (CD45(-), TER119(-), c-kit-1(-), and Flk-1(-)), oligopotent progenitor β-cells (CD45(-), TER119(-), CD133(+), and CD49f(low)), and insulinproducing β-cells (Pdx1(+)). Pancreatic infl ammation was preceded by elevation of the number of short-term hematopoietic stem cells (Lin-Sca-1(+)c-kit(+)CD34(+)) relative to long-term cells (Lin(-)Sca-1(+)c-kit(+)CD34(-)) in the bone marrow as well as recruitment of hematopoietic stem and progenitor cells into circulation. Transplantation of bone marrow hematopoietic stem and progenitor cells from diabetic C57Bl/6 donor mice to recipient CBA mice with 5-fluorouracilinduced leukopenia accelerated regeneration of granulocytopoiesis in recipient mice. PMID:26906195

  5. Nonmyeloablative allogeneic hematopoietic cell transplantation

    PubMed Central

    Storb, Rainer; Sandmaier, Brenda M.

    2016-01-01

    Most hematological malignancies occur in older patients. Until recently these patients and those with comorbidities were not candidates for treatment with allogeneic hematopoietic transplantation because they were unable to tolerate the heretofore used high-dose conditioning regimens. The finding that many of the cures achieved with allogeneic hematopoietic transplantation were due to graft-versus-tumor effects led to the development of less toxic and well-tolerated reduced intensity and nonmyeloablative regimens. These regimens enabled allogeneic engraftment, thereby setting the stage for graft-versus-tumor effects. This review summarizes the encouraging early results seen with the new regimens and discusses the two hurdles that need to be overcome for achieving even greater success, disease relapse and graft-versus-host disease. PMID:27132278

  6. Making a Hematopoietic Stem Cell

    PubMed Central

    Daniel, Michael G.; Pereira, Carlos-Filipe; Lemischka, Ihor R.; Moore, Kateri A.

    2016-01-01

    Previous attempts to either generate or expand hematopoietic stem cells (HSCs) in vitro have involved either ex vivo expansion of pre-existing patient or donor HSCs or de novo generation from pluripotent stem cells (PSCs), comprising both embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). iPSCs alleviated ESC ethical issues but attempts to generate functional mature hematopoietic stem and progenitor cells (HSPCs) have been largely unsuccessful. New efforts focus on directly reprogramming somatic cells into definitive HSCs and HSPCs. To meet clinical needs and to advance drug discovery and stem cell therapy, alternative approaches are necessary. In this review, we synthesize the strategies used and the key findings made in recent years by those trying to make an HSC. PMID:26526106

  7. The role of Lin28b in myeloid and mast cell differentiation and mast cell malignancy

    PubMed Central

    Wang, Leo D.; Rao, Tata Nageswara; Rowe, R. Grant; Nguyen, Phi T.; Sullivan, Jessica L.; Pearson, Daniel S.; Doulatov, Sergei; Wu, Linwei; Lindsley, R. Coleman; Zhu, Hao; DeAngelo, Daniel J.; Daley, George Q.; Wagers, Amy J.

    2015-01-01

    Mast cells are critical components of the innate immune system and important for host defense, allergy, autoimmunity, tissue regeneration, and tumor progression. Dysregulated mast cell development leads to systemic mastocytosis, a clinically variable but often devastating family of hematologic disorders. Here we report that induced expression of Lin28, a heterochronic gene and pluripotency factor implicated in driving a fetal hematopoietic program, caused mast cell accumulation in adult mice in target organs such as the skin and peritoneal cavity. In vitro assays revealed a skewing of myeloid commitment in LIN28B-expressing hematopoietic progenitors, with increased levels of LIN28B in common myeloid and basophil-mast cell progenitors altering gene expression patterns to favor cell fate choices that enhanced mast cell specification. In addition, LIN28B-induced mast cells appeared phenotypically and functionally immature, and in vitro assays suggested a slowing of mast cell terminal differentiation in the context of LIN28B upregulation. Finally, interrogation of human mast cell leukemia samples revealed upregulation of LIN28B in abnormal mast cells from patients with systemic mastocytosis (SM). This work identifies Lin28 as a novel regulator of innate immune function and a new protein of interest in mast cell disease. PMID:25655194

  8. JAK2 V617F in Myeloid Disorders: Molecular Diagnostic Techniques and Their Clinical Utility

    PubMed Central

    Steensma, David P.

    2006-01-01

    In early 2005, several groups of investigators studying myeloid malignancies described a novel somatic point mutation (V617F) in the conserved autoinhibitory pseudokinase domain of the Janus kinase 2 (JAK2) protein, which plays an important role in normal hematopoietic growth factor signaling. The V617F mutation is present in blood and marrow from a large proportion of patients with classic BCR/ABL-negative chronic myeloproliferative disorders and of a few patients with other clonal hematological diseases such as myelodysplastic syndrome, atypical myeloproliferative disorders, and acute myeloid leukemia. The JAK2 V617F mutation causes constitutive activation of the kinase, with deregulated intracellular signaling that mimics continuous hematopoietic growth factor stimulation. Within 7 months of the first electronic publication describing this new mutation, clinical molecular diagnostic laboratories in the United States and Europe began offering JAK2 mutation testing on a fee-for-service basis. Here, I review the various techniques used by research groups and clinical laboratories to detect the genetic mutation underlying JAK2 V617F, including fluorescent dye chemistry sequencing, allele-specific polymerase chain reaction (PCR), real-time PCR, DNA-melting curve analysis, pyrosequencing, and others. I also discuss diagnostic sensitivity, performance, and other practical concerns relevant to the clinical laboratorian in addition to the potential diagnostic utility of JAK2 mutation tests. PMID:16931578

  9. Aberrant Myeloid Differentiation Contributes to the Development of Osteoporosis in Neurofibromatosis Type 1.

    PubMed

    Rhodes, Steven D; Yang, Feng-Chun

    2016-02-01

    Neurofibromatosis type 1 (NF1), also known as von Recklinghausen disease, is a common autosomal dominant genetic disorder affecting approximately 1 in 3000 individuals worldwide. NF1 results from heritable or spontaneous mutations of the NF1 tumor suppressor gene. NF1 encodes the protein neurofibromin, which functions to negatively regulate Ras-activity. Approximately 50 % of NF1 patients develop osteopenia or osteoporosis, resulting in significantly increased rates of long-bone fracture and morbidity. While defective osteoblast bone anabolism has been implicated as a central factor in the pathogenesis of NF1 associated skeletal deficits, recent data suggest that NF1 (Nf1) haploinsufficiency within the hematopoietic compartment, particularly in osteoclasts and myeloid progenitors, plays a pivotal role in engendering NF1 osseous manifestations. In this chapter, we review the latest data from clinical studies and murine models delineating a critical role for hematopoietic compartment, myeloid progenitors of NF1 (Nf1) haploinsufficient and their progeny-osteoclasts, in the pathogenesis of NF1 associated osteopenia/osteoporosis and discuss putative targets for future therapeutics. PMID:26932441

  10. Drosophila as a model for the two myeloid blood cell systems in vertebrates

    PubMed Central

    Gold, Katrina S.; Brückner, Katja

    2016-01-01

    Fish, mice and men rely on two coexisting myeloid blood cell systems. One is sustained by hematopoietic progenitor cells, which reside in specialized microenvironments in hematopoietic organs and give rise to cells of the monocyte lineage. The other system corresponds to the independent lineage of self-renewing tissue macrophages, which colonize organs during embryonic development and are maintained during later life by proliferation in local tissue microenvironments. However, little is known about the nature of these microenvironments and their regulation. Moreover, many vertebrate tissues contain a mix of both tissue-resident and monocyte-derived macrophages, posing a challenge to the study of lineage-specific regulatory mechanisms and function. This review highlights how research in the simple model organism Drosophila melanogaster can address many of these outstanding questions in the field. Drawing parallels between hematopoiesis in Drosophila and vertebrates, we illustrate the evolutionary conservation of the two myeloid systems across animal phyla. Much like vertebrates, Drosophila possesses a lineage of self-renewing tissue-resident macrophages, as well as a ‘definitive’ lineage of macrophages that derive from hematopoiesis in the progenitor-based lymph gland. We summarize key findings from Drosophila hematopoiesis that illustrate how local microenvironments, systemic signals, immune challenges and nervous inputs regulate adaptive responses of tissue-resident macrophages and progenitor-based hematopoiesis to achieve optimal fitness of the animal. PMID:24946019

  11. Biological implications of somatic DDX41 p.R525H mutation in acute myeloid leukemia.

    PubMed

    Kadono, Moe; Kanai, Akinori; Nagamachi, Akiko; Shinriki, Satoru; Kawata, Jin; Iwato, Koji; Kyo, Taiichi; Oshima, Kumi; Yokoyama, Akihiko; Kawamura, Takeshi; Nagase, Reina; Inoue, Daichi; Kitamura, Toshio; Inaba, Toshiya; Ichinohe, Tatsuo; Matsui, Hirotaka

    2016-08-01

    The DDX41 gene, encoding a DEAD-box type ATP-dependent RNA helicase, is rarely but reproducibly mutated in myeloid diseases. The acquired mutation in DDX41 is highly concentrated at c.G1574A (p.R525H) in the conserved motif VI located at the C-terminus of the helicase core domain where ATP interacts and is hydrolyzed. Therefore, it is likely that the p.R525H mutation perturbs ATPase activity in a dominant-negative manner. In this study, we screened for the DDX41 mutation of CD34-positive tumor cells based on mRNA sequencing and identified the p.R525H mutation in three cases among 23 patients. Intriguingly, these patients commonly exhibited acute myeloid leukemia (AML) with peripheral blood cytopenias and low blast counts, suggesting that the mutation inhibits the growth and differentiation of hematopoietic cells. Data from cord blood cells and leukemia cell lines suggest a role for DDX41 in preribosomal RNA processing, in which the expression of the p.R525H mutant causes a certain ribosomopathy phenotype in hematopoietic cells by suppressing MDM2-mediated RB degradation, thus triggering the inhibition of E2F activity. This study uncovered a pathogenic role of p.R525H DDX41 in the slow growth rate of tumor cells. Age-dependent epigenetic alterations or other somatic changes might collaborate with the mutation to cause AML. PMID:27174803

  12. What Are the Key Statistics about Acute Myeloid Leukemia?

    MedlinePlus

    ... for acute myeloid leukemia? What are the key statistics about acute myeloid leukemia? The American Cancer Society’s ... myeloid leukemia .” Visit the American Cancer Society’s Cancer Statistics Center for more key statistics. Last Medical Review: ...

  13. Genetics Home Reference: core binding factor acute myeloid leukemia

    MedlinePlus

    ... acute myeloid leukemia core binding factor acute myeloid leukemia Enable Javascript to view the expand/collapse boxes. ... Close All Description Core binding factor acute myeloid leukemia (CBF-AML) is one form of a cancer ...

  14. Deficiency of the ribosome biogenesis gene Sbds in hematopoietic stem and progenitor cells causes neutropenia in mice by attenuating lineage progression in myelocytes.

    PubMed

    Zambetti, Noemi A; Bindels, Eric M J; Van Strien, Paulina M H; Valkhof, Marijke G; Adisty, Maria N; Hoogenboezem, Remco M; Sanders, Mathijs A; Rommens, Johanna M; Touw, Ivo P; Raaijmakers, Marc H G P

    2015-10-01

    Shwachman-Diamond syndrome is a congenital bone marrow failure disorder characterized by debilitating neutropenia. The disease is associated with loss-of-function mutations in the SBDS gene, implicated in ribosome biogenesis, but the cellular and molecular events driving cell specific phenotypes in ribosomopathies remain poorly defined. Here, we established what is to our knowledge the first mammalian model of neutropenia in Shwachman-Diamond syndrome through targeted downregulation of Sbds in hematopoietic stem and progenitor cells expressing the myeloid transcription factor CCAAT/enhancer binding protein α (Cebpa). Sbds deficiency in the myeloid lineage specifically affected myelocytes and their downstream progeny while, unexpectedly, it was well tolerated by rapidly cycling hematopoietic progenitor cells. Molecular insights provided by massive parallel sequencing supported cellular observations of impaired cell cycle exit and formation of secondary granules associated with the defect of myeloid lineage progression in myelocytes. Mechanistically, Sbds deficiency activated the p53 tumor suppressor pathway and induced apoptosis in these cells. Collectively, the data reveal a previously unanticipated, selective dependency of myelocytes and downstream progeny, but not rapidly cycling progenitors, on this ubiquitous ribosome biogenesis protein, thus providing a cellular basis for the understanding of myeloid lineage biased defects in Shwachman-Diamond syndrome. PMID:26185170

  15. Deficiency of the ribosome biogenesis gene Sbds in hematopoietic stem and progenitor cells causes neutropenia in mice by attenuating lineage progression in myelocytes

    PubMed Central

    Zambetti, Noemi A.; Bindels, Eric M. J.; Van Strien, Paulina M. H.; Valkhof, Marijke G.; Adisty, Maria N.; Hoogenboezem, Remco M.; Sanders, Mathijs A.; Rommens, Johanna M.; Touw, Ivo P.; Raaijmakers, Marc H. G. P.

    2015-01-01

    Shwachman-Diamond syndrome is a congenital bone marrow failure disorder characterized by debilitating neutropenia. The disease is associated with loss-of-function mutations in the SBDS gene, implicated in ribosome biogenesis, but the cellular and molecular events driving cell specific phenotypes in ribosomopathies remain poorly defined. Here, we established what is to our knowledge the first mammalian model of neutropenia in Shwachman-Diamond syndrome through targeted downregulation of Sbds in hematopoietic stem and progenitor cells expressing the myeloid transcription factor CCAAT/enhancer binding protein α (Cebpa). Sbds deficiency in the myeloid lineage specifically affected myelocytes and their downstream progeny while, unexpectedly, it was well tolerated by rapidly cycling hematopoietic progenitor cells. Molecular insights provided by massive parallel sequencing supported cellular observations of impaired cell cycle exit and formation of secondary granules associated with the defect of myeloid lineage progression in myelocytes. Mechanistically, Sbds deficiency activated the p53 tumor suppressor pathway and induced apoptosis in these cells. Collectively, the data reveal a previously unanticipated, selective dependency of myelocytes and downstream progeny, but not rapidly cycling progenitors, on this ubiquitous ribosome biogenesis protein, thus providing a cellular basis for the understanding of myeloid lineage biased defects in Shwachman-Diamond syndrome. PMID:26185170

  16. Chronic myeloid leukemia with monoclonal gammopathy terminating in myeloid crisis and immunoblastic lymphoma.

    PubMed

    Larocca, L M; Zollino, M; Carbone, A; Eboli, M L; Mango, G; Leone, G

    1989-04-30

    A patient, with chronic myeloid leukemia and IgA monoclonal gammopathy, who contemporaneously developed myeloid blast crisis and immunoblastic lymphoma is reported. Cytogenetic studies showed complex chromosome abnormalities concerning chromosomes 8, 14 and 22, other than the Ph chromosome. A possible relationship between the emergence of immunoblasts from slow proliferating lymphoplasmacytoid cells, myeloid blasts crisis and chromosomal changes is discussed. PMID:2741214

  17. Cohesin loss alters adult hematopoietic stem cell homeostasis, leading to myeloproliferative neoplasms

    PubMed Central

    Mullenders, Jasper; Aranda-Orgilles, Beatriz; Lhoumaud, Priscillia; Keller, Matthew; Pae, Juhee; Wang, Kun; Kayembe, Clarisse; Rocha, Pedro P.; Raviram, Ramya; Gong, Yixiao; Premsrirut, Prem K.; Tsirigos, Aristotelis; Bonneau, Richard; Skok, Jane A.; Cimmino, Luisa; Hoehn, Daniela

    2015-01-01

    The cohesin complex (consisting of Rad21, Smc1a, Smc3, and Stag2 proteins) is critically important for proper sister chromatid separation during mitosis. Mutations in the cohesin complex were recently identified in a variety of human malignancies including acute myeloid leukemia (AML). To address the potential tumor-suppressive function of cohesin in vivo, we generated a series of shRNA mouse models in which endogenous cohesin can be silenced inducibly. Notably, silencing of cohesin complex members did not have a deleterious effect on cell viability. Furthermore, knockdown of cohesin led to gain of replating capacity of mouse hematopoietic progenitor cells. However, cohesin silencing in vivo rapidly altered stem cells homeostasis and myelopoiesis. Likewise, we found widespread changes in chromatin accessibility and expression of genes involved in myelomonocytic maturation and differentiation. Finally, aged cohesin knockdown mice developed a clinical picture closely resembling myeloproliferative disorders/neoplasms (MPNs), including varying degrees of extramedullary hematopoiesis (myeloid metaplasia) and splenomegaly. Our results represent the first successful demonstration of a tumor suppressor function for the cohesin complex, while also confirming that cohesin mutations occur as an early event in leukemogenesis, facilitating the potential development of a myeloid malignancy. PMID:26438359

  18. Hematopoietic stem-cell transplantation in the developing world: experience from a center in Western India.

    PubMed

    Shah, Chirag A; Karanwal, Arun; Desai, Maharshi; Pandya, Munjal; Shah, Ravish; Shah, Rutvij

    2015-01-01

    We describe our experience of first 50 consecutive hematopoietic stem-cell transplants (HSCT) done between 2007 and 2012 at the Apollo Hospital, Gandhinagar, 35 autologous HSCT and 15 allogeneic HSCT. Indications for autologous transplant were multiple myeloma, non-Hodgkin lymphoma, Hodgkin lymphoma, and acute myeloid leukemia, and indications for allogeneic transplants were thalassemia major, aplastic anaemia, chronic myeloid leukemia, and acute lymphoblastic and myeloid leukaemia. The median age of autologous and allogeneic patient's cohort was 50 years and 21 years, respectively. Median follow-up period for all patients was 39 months. Major early complications were infections, mucositis, acute graft versus host disease, and venoocclusive disease. All of our allogeneic and autologous transplant patients survived during the first month of transplant. Transplant related mortality (TRM) was 20% (N = 3) in our allogeneic and 3% (N = 1) in autologous patients. Causes of these deaths were disease relapse, sepsis, hemorrhagic complications, and GVHD. 46% of our autologous and 47% of our allogeneic patients are in complete remission phase after a median follow-up of 39 months. 34% of our autologous patients and 13% of our allogeneic patients had disease relapse. Overall survival rate in our autologous and allogeneic patients is 65.7% and 57.1%, respectively. Our results are comparable to many national and international published reports. PMID:25722722

  19. Hematopoietic lineage skewing and intestinal epithelia degeneration in aged mice with telomerase RNA component deletion.

    PubMed

    Chen, Jichun; Bryant, Mark A; Dent, James J; Sun, Yu; Desierto, Marie J; Young, Neal S

    2015-12-01

    A deletion of a telomerase RNA component (Terc(-/-)) in C57BL/6 (B6) mice resulted in hematopoietic lineage skewing with increased neutrophils and CD11b(+) myeloid cells and decreased red blood cells and CD45R(+) B lymphocytes when animals reach ages older than 12 months. There was no decline in bone marrow (BM) c-Kit(+)Sca-1(+)Lin(-) (KSL) cells in old Terc(-/-) mice, and the lineage skewing phenomenon was not transferred when BM cells from old Terc(-/-) donors were transplanted into young B6 recipients. Necropsy and histological examinations found minimal to no change in the lung, spleen and liver but detected severe epithelia degeneration, ulceration and infection in small and large intestines, leading to enteritis, typhlitis and colitis in old Terc(-/-) mice. In a mouse model of dextran-sulfate-sodium-induced typhlitis and colitis, development of intestinal pathology was associated with increases in neutrophils and CD11b(+) myeloid cells and a decrease in CD45R(+) B cells, similar to those observed in old Terc(-/-) mice. Treatment of 11-13 month old Terc(-/-) mice with antibiotic trimethoprim-sulfa water reduced neutrophils and myeloid cells and increased B lymphocytes in the blood, indicating that mitigation of intestinal infection and inflammation could alleviate hematological abnormalities in old Terc(-/-) animals. PMID:26523501

  20. Hematopoietic Stem-Cell Transplantation in the Developing World: Experience from a Center in Western India

    PubMed Central

    Shah, Chirag A.; Karanwal, Arun; Desai, Maharshi; Pandya, Munjal; Shah, Ravish; Shah, Rutvij

    2015-01-01

    We describe our experience of first 50 consecutive hematopoietic stem-cell transplants (HSCT) done between 2007 and 2012 at the Apollo Hospital, Gandhinagar, 35 autologous HSCT and 15 allogeneic HSCT. Indications for autologous transplant were multiple myeloma, non-Hodgkin lymphoma, Hodgkin lymphoma, and acute myeloid leukemia, and indications for allogeneic transplants were thalassemia major, aplastic anaemia, chronic myeloid leukemia, and acute lymphoblastic and myeloid leukaemia. The median age of autologous and allogeneic patient's cohort was 50 years and 21 years, respectively. Median follow-up period for all patients was 39 months. Major early complications were infections, mucositis, acute graft versus host disease, and venoocclusive disease. All of our allogeneic and autologous transplant patients survived during the first month of transplant. Transplant related mortality (TRM) was 20% (N = 3) in our allogeneic and 3% (N = 1) in autologous patients. Causes of these deaths were disease relapse, sepsis, hemorrhagic complications, and GVHD. 46% of our autologous and 47% of our allogeneic patients are in complete remission phase after a median follow-up of 39 months. 34% of our autologous patients and 13% of our allogeneic patients had disease relapse. Overall survival rate in our autologous and allogeneic patients is 65.7% and 57.1%, respectively. Our results are comparable to many national and international published reports. PMID:25722722

  1. Sustained expression of microRNA-155 in hematopoietic stem cells causes a myeloproliferative disorder.

    PubMed

    O'Connell, Ryan M; Rao, Dinesh S; Chaudhuri, Aadel A; Boldin, Mark P; Taganov, Konstantin D; Nicoll, John; Paquette, Ronald L; Baltimore, David

    2008-03-17

    Mammalian microRNAs are emerging as key regulators of the development and function of the immune system. Here, we report a strong but transient induction of miR-155 in mouse bone marrow after injection of bacterial lipopolysaccharide (LPS) correlated with granulocyte/monocyte (GM) expansion. Demonstrating the sufficiency of miR-155 to drive GM expansion, enforced expression in mouse bone marrow cells caused GM proliferation in a manner reminiscent of LPS treatment. However, the miR-155-induced GM populations displayed pathological features characteristic of myeloid neoplasia. Of possible relevance to human disease, miR-155 was found to be overexpressed in the bone marrow of patients with certain subtypes of acute myeloid leukemia (AML). Furthermore, miR-155 repressed a subset of genes implicated in hematopoietic development and disease. These data implicate miR-155 as a contributor to physiological GM expansion during inflammation and to certain pathological features associated with AML, emphasizing the importance of proper miR-155 regulation in developing myeloid cells during times of inflammatory stress. PMID:18299402

  2. Transformation of human mesenchymal cells and skin fibroblasts into hematopoietic cells.

    PubMed

    Harris, David M; Hazan-Haley, Inbal; Coombes, Kevin; Bueso-Ramos, Carlos; Liu, Jie; Liu, Zhiming; Li, Ping; Ravoori, Murali; Abruzzo, Lynne; Han, Lin; Singh, Sheela; Sun, Michael; Kundra, Vikas; Kurzrock, Razelle; Estrov, Zeev

    2011-01-01

    Patients with prolonged myelosuppression require frequent platelet and occasional granulocyte transfusions. Multi-donor transfusions induce alloimmunization, thereby increasing morbidity and mortality. Therefore, an autologous or HLA-matched allogeneic source of platelets and granulocytes is needed. To determine whether nonhematopoietic cells can be reprogrammed into hematopoietic cells, human mesenchymal stromal cells (MSCs) and skin fibroblasts were incubated with the demethylating agent 5-azacytidine (Aza) and the growth factors (GF) granulocyte-macrophage colony-stimulating factor and stem cell factor. This treatment transformed MSCs to round, non-adherent cells expressing T-, B-, myeloid-, or stem/progenitor-cell markers. The transformed cells engrafted as hematopoietic cells in bone marrow of immunodeficient mice. DNA methylation and mRNA array analysis suggested that Aza and GF treatment demethylated and activated HOXB genes. Indeed, transfection of MSCs or skin fibroblasts with HOXB4, HOXB5, and HOXB2 genes transformed them into hematopoietic cells. Further studies are needed to determine whether transformed MSCs or skin fibroblasts are suitable for therapy. PMID:21731684

  3. Association of acute myeloid leukemia's most immature phenotype with risk groups and outcomes.

    PubMed

    Gerber, Jonathan M; Zeidner, Joshua F; Morse, Sarah; Blackford, Amanda L; Perkins, Brandy; Yanagisawa, Breann; Zhang, Hao; Morsberger, Laura; Karp, Judith; Ning, Yi; Gocke, Christopher D; Rosner, Gary L; Smith, B Douglas; Jones, Richard J

    2016-05-01

    The precise phenotype and biology of acute myeloid leukemia stem cells remain controversial, in part because the "gold standard" immunodeficient mouse engraftment assay fails in a significant fraction of patients and identifies multiple cell-types in others. We sought to analyze the clinical utility of a novel assay for putative leukemia stem cells in a large prospective cohort. The leukemic clone's most primitive hematopoietic cellular phenotype was prospectively identified in 109 newly-diagnosed acute myeloid leukemia patients, and analyzed against clinical risk groups and outcomes. Most (80/109) patients harbored CD34(+)CD38(-) leukemia cells. The CD34(+)CD38(-) leukemia cells in 47 of the 80 patients displayed intermediate aldehyde dehydrogenase expression, while normal CD34(+)CD38(-) hematopoietic stem cells expressed high levels of aldehyde dehydrogenase. In the other 33/80 patients, the CD34(+)CD38(-) leukemia cells exhibited high aldehyde dehydrogenase activity, and most (28/33, 85%) harbored poor-risk cytogenetics or FMS-like tyrosine kinase 3 internal tandem translocations. No CD34(+) leukemia cells could be detected in 28/109 patients, including 14/21 patients with nucleophosmin-1 mutations and 6/7 acute promyelocytic leukemia patients. The patients with CD34(+)CD38(-) leukemia cells with high aldehyde dehydrogenase activity manifested a significantly lower complete remission rate, as well as poorer event-free and overall survivals. The leukemic clone's most immature phenotype was heterogeneous with respect to CD34, CD38, and ALDH expression, but correlated with acute myeloid leukemia risk groups and outcomes. The strong clinical correlations suggest that the most immature phenotype detectable in the leukemia might serve as a biomarker for "clinically-relevant" leukemia stem cells. ClinicalTrials.gov: NCT01349972. PMID:26819054

  4. Mechanisms of resistance in patients with chronic myeloid leukemia treated with tyrosine kinase inhibitors.

    PubMed

    Perekhrestenko, T; Diachenko, M; Sviezhentseva, I; Gordienko, A; Bilko, D

    2015-03-01

    Up to date, two major mechanisms have been proposed as an explanation for myeloid cells expansion in chronic myeloid leukemia (CML). One is a reduced susceptibility of hematopoietic stem or progenitor cells to apoptosis, while the other one is an increased activity within the hematopoietic progenitor cell population. The aim of the study was to identify specific features of functional activity, proliferation rates and differentiation potential of CML hematopoietic progenitor cells of patients treated with tyrosine kinase inhibitors (TKI) by identifying number of Ki-67, Bcl-2 and CD34 positive cells in bone marrow, as well as in vitro colony-forming unit assay in patients with different response to the TKI therapy. Our results indicated that there was a significant decline in proliferation activity of HSCs and HPCs in group of patients with optimal response to the TKI therapy. Correlation analysis, performed on individual basis for patients independently of response to the TKI therapy demonstrated that there was a negative correlation (ρ=0.7648) between the number of Ki67+ and CD34+ cells. As to colony to cluster ratio our results showed, that there is a correlation (ρ=0.6783) between CCR index and number of bone marrow cells with Philadelphia chromosome. It was indicated, that index of maturation correlates with level of bone marrow cells, containing Philadelphia chromosome, so as with percentage of CD34+, Bcl-2+, Pgp-170+ and Ki67+ cells in bone marrow of CML patients. In summary, obtained results suggest that different mechanisms (bcr-abl dependent and independent) may be involved in CML progression process in the same time. Disease prognosis should be preferably carried out on an individual basis. PMID:25879558

  5. Targeted alpha-particle immunotherapy for acute myeloid leukemia.

    PubMed

    Jurcic, Joseph G; Rosenblat, Todd L

    2014-01-01

    Because alpha-particles have a shorter range and a higher linear energy transfer (LET) compared with beta-particles, targeted alpha-particle immunotherapy offers the potential for more efficient tumor cell killing while sparing surrounding normal cells. To date, clinical studies of alpha-particle immunotherapy for acute myeloid leukemia (AML) have focused on the myeloid cell surface antigen CD33 as a target using the humanized monoclonal antibody lintuzumab. An initial phase I study demonstrated the safety, feasibility, and antileukemic effects of bismuth-213 ((213)Bi)-labeled lintuzumab. In a subsequent study, (213)Bi-lintuzumab produced remissions in some patients with AML after partial cytoreduction with cytarabine, suggesting the utility of targeted alpha-particle therapy for small-volume disease. The widespread use of (213)Bi, however, is limited by its short half-life. Therefore, a second-generation construct containing actinium-225 ((225)Ac), a radiometal that generates four alpha-particle emissions, was developed. A phase I trial demonstrated that (225)Ac-lintuzumab is safe at doses of 3 μCi/kg or less and has antileukemic activity across all dose levels studied. Fractionated-dose (225)Ac-lintuzumab in combination with low-dose cytarabine (LDAC) is now under investigation for the management of older patients with untreated AML in a multicenter trial. Preclinical studies using (213)Bi- and astatine-211 ((211)At)-labeled anti-CD45 antibodies have shown that alpha-particle immunotherapy may be useful as part conditioning before hematopoietic cell transplantation. The use of novel pretargeting strategies may further improve target-to-normal organ dose ratios. PMID:24857092

  6. Chronic myeloid leukemia relapsing ten years after allogenic bone marrow transplantation.

    PubMed

    Hino, Yutaro; Doki, Noriko; Yamamoto, Keita; Senoo, Yasushi; Sasajima, Satoshi; Sakaguchi, Masahiro; Hattori, Keiichiro; Kaito, Satoshi; Kurosawa, Shuhei; Harada, Kaito; Ikegawa, Shuntaro; Watanabe, Daisuke; Hagino, Takeshi; Yoshioka, Kosuke; Watakabe, Kyoko; Igarashi, Aiko; Najima, Yuho; Kobayashi, Takeshi; Kakihana, Kazuhiko; Sakamaki, Hisashi; Ohashi, Kazuteru

    2016-05-01

    A 58-year-old female was diagnosed with Philadelphia chromosome positive chronic myeloid leukemia (CML) in blast crisis (BC) in 2004. The patient received imatinib, which quickly induced molecular remission, and subsequently underwent bone marrow transplantation (BMT) from an unrelated human leukocyte antigen (HLA)-identical donor. The post-transplant clinical course was essentially uneventful. In 2014, ten years after the BMT, the patient was admitted to our hospital complaining of lymphadenopathy, and blasts were observed in peripheral blood. The patient was diagnosed as having a CML relapse in myeloid BC, with leukemic infiltration in lymph nodes, and was treated with dasatinib. Subsequently, pleural effusion developed and nilotinib was administered, which induced normal blood counts without blasts and partial cytogenetic remission, one month after administration. Six months after the relapse, this patient underwent a second BMT from an HLA-matched unrelated donor. Recent studies have demonstrated the cumulative incidence of CML relapse more than five years after allogeneic hematopoietic stem cell transplantation (allo-HSCT) to be higher than in acute myeloid leukemia. Although rare, the possibility of late relapse should be considered in patients diagnosed with CML after allo-HSCT. PMID:27263786

  7. FOXP1 Expression in Normal and Neoplastic Erythroid and Myeloid Cells.

    PubMed

    Lovrić, Eva; Pavlov, Katarina Horvat; Korać, Petra; Dominis, Mara

    2015-09-01

    FOXP1 protein was firstly analyzed in normal tissues, and afterwards in different tumor tissues, mainly carcinoma and lymphoma. In B-cell malignancies, its role was well explored; its expression was shown to be connected with disease prognosis in certain B-non Hodgkin lymphomas. In this study, 16 bone marrow trephine samples from patients with no hematopoietic malignancies and 10 samples from peripheral blood of healthy individuals were immunostained with anti-FOXP1 antibody. Positive cells in bone marrows were not only lymphocytes, but also cells that are immunohistochemically positive for glycophorin C or myeloperoxidase. Peripheral blood samples showed no other positive cells, but small round lymphocytes. Additionally 60 samples from patients with myeloid lineage neoplasms were analyzed. 25 samples from patients with myelodysplastic syndrome (MDS) and 35 patients with myeloproliferative disease (MPD) were double immunostained with anti-FOXP1/anti-glycophorin C and anti-FOXP1/anti-myeloperoxidase antibodies. FOXP1 was found to be expressed in 22 cases of MDS and in none of MPD cases. Its expression in MDS was observed mostly in myeloperoxidase positive cells in contrast to gylcophorin C positive cells. Only two cases revealed both myeloperoxidase positive cells and gylcophorin C positive cells expressing FOXP1 transcription factor. Our results show that FOXP1 is present in normal cells of erythroid and myeloid linages and thus suggest its possible role in development of all hematopoetic cells as well as possible involvement in neoplasm development of myeloid disorders. PMID:26898077

  8. Neurofibromin Deficient Myeloid Cells are Critical Mediators of Aneurysm Formation In Vivo

    PubMed Central

    Li, Fang; Downing, Brandon D.; Smiley, Lucy C.; Mund, Julie A.; DiStasi, Matthew R.; Bessler, Waylan K.; Sarchet, Kara N.; Hinds, Daniel M.; Kamendulis, Lisa M.; Hingtgen, Cynthia M.; Case, Jamie; Clapp, D. Wade; Conway, Simon J.; Stansfield, Brian K.; Ingram, David A.

    2014-01-01

    Background Neurofibromatosis Type 1 (NF1) is a genetic disorder resulting from mutations in the NF1 tumor suppressor gene. Neurofibromin, the protein product of NF1, functions as a negative regulator of Ras activity in circulating hematopoietic and vascular wall cells, which are critical for maintaining vessel wall homeostasis. NF1 patients have evidence of chronic inflammation resulting in development of premature cardiovascular disease, including arterial aneurysms, which may manifest as sudden death. However, the molecular pathogenesis of NF1 aneurysm formation is unknown. Method and Results Utilizing an angiotensin II-induced aneurysm model, we demonstrate that heterozygous inactivation of Nf1 (Nf1+/−) enhanced aneurysm formation with myeloid cell infiltration and increased oxidative stress in the vessel wall. Using lineage-restricted transgenic mice, we show loss of a single Nf1 allele in myeloid cells is sufficient to recapitulate the Nf1+/− aneurysm phenotype in vivo. Finally, oral administration of simvastatin or the antioxidant apocynin, reduced aneurysm formation in Nf1+/− mice. Conclusion These data provide genetic and pharmacologic evidence that Nf1+/− myeloid cells are the cellular triggers for aneurysm formation in a novel model of NF1 vasculopathy and provide a potential therapeutic target. PMID:24370551

  9. Splenic myeloid metaplasia, histiocytosis, and hypersplenism in the dog (65 cases).

    PubMed

    Spangler, W L; Kass, P H

    1999-11-01

    Splenectomy specimens from 65 dogs with severe, diffuse, sustained, and progressive splenomegaly were examined. The clinical signs, hematology, and serum chemistry values in for the dogs were not useful diagnostic features. Microscopic changes in the spleens were distinctive and consisted of 1) myeloid metaplasia, 2) histiocytosis, 3) erythrophagocytosis, and 4) thrombosis with segmental infarction. Ultrastructural features suggested proliferative changes in the splenic reticular cells and macrophages (reticular meshwork) that described a continuum from reactive changes associated with immunologic damage of erythrocytes to neoplastic proliferation of histiocytic components. Thirty percent of the dogs survived 12 months. Approximately one half (53%) of the dogs with complete postmortem evaluations showed multiorgan involvement with a tissue distribution and cell morphology consistent with histiocytic neoplasia. For the remaining dogs (47%), only splenic pathology was consistently present, and a specific cause of death was often not evident. Distinctive histologic changes in the splenic tissues-including mitotic activity, erythrophagocytosis, giant cell formation, thrombosis/ infarction, and the proportion and distribution of histiocytic and hematopoietic cells-were statistically evaluated for prognostic relevance. The presence of giant cells was the only reliable prognostic feature, and that was indicative of a fatal outcome. These descriptive changes of myeloid metaplasia in the canine spleen are compared with the human clinical and pathologic syndromes of 1) agnogenic myeloid metaplasia, 2) hemophagocytic syndromes, and 3) hypersplenism. These diseases in humans produce histopathologic changes in the spleen that are similar to those observed in the canine splenic tissue we examined in this study. PMID:10568439

  10. Cryopreserved Ex Vivo-Expanded Allogeneic Myeloid Progenitor Cell Product Protects Neutropenic Mice From a Lethal Fungal Infection.

    PubMed

    Domen, Jos; Christensen, Julie L; Gille, Daphne; Smith-Berdan, Stephanie; Fong, Timothy; Brown, Janice M Y; Sedello, Anna K

    2016-01-01

    Severe neutropenia induced by chemotherapy or conditioning for hematopoietic cell transplantation often results in morbidity and mortality due to infection by opportunistic pathogens. A system has been developed to generate ex vivo-expanded mouse myeloid progenitor cells (mMPCs) that produce functional neutrophils in vivo upon transplantation in a pathogen challenge model. It has previously been demonstrated that transplantation of large numbers of freshly isolated myeloid progenitors from a single donor provides survival benefit in radiation-induced neutropenic mice. In the present work, an ex vivo-expanded and cryopreserved mMPC product generated from an allogeneic donor pool retains protective activity in vivo in a lethal fungal infection model. Infusion of the allogeneic pooled mMPC product is effective in preventing death from invasive Aspergillus fumigatus in neutropenic animals, and protection is dose dependent. Cell progeny from the mMPC product is detected in the bone marrow, spleen, blood, and liver by flow cytometry 1 week postinfusion but is no longer evident in most animals 4 weeks posttransplant. In this model, the ex vivo-generated pooled allogeneic mMPC product (i) expands and differentiates in vivo; (ii) is functional and prevents death from invasive fungal infection; and (iii) does not permanently engraft or cause allosensitization. These data suggest that an analogous ex vivo-expanded human myeloid progenitor cell product may be an effective off-the-shelf bridging therapy for the infectious complications that develop during hematopoietic recovery following hematopoietic cell transplantation or intensive chemotherapy. PMID:25812169

  11. Plasticity of hematopoietic stem cells.

    PubMed

    Ogawa, Makio; LaRue, Amanda C; Mehrotra, Meenal

    2015-01-01

    Almost two decades ago, a number of cell culture and preclinical transplantation studies suggested the striking concept of the tissue-reconstituting ability of hematopoietic stem cells (HSCs). While this heralded an exciting time of radically new therapies for disorders of many organs and tissues, the concept was soon mired by controversy and remained dormant. This chapter provides a brief review of evidence for HSC plasticity including our findings based on single HSC transplantation in mouse. These studies strongly support the concept that HSCs are pluripotent and may be the source for the majority, if not all, of the cell types in our body. PMID:26590762

  12. Acute myeloid leukemia in the era of precision medicine: recent advances in diagnostic classification and risk stratification

    PubMed Central

    Kansal, Rina

    2016-01-01

    Acute myeloid leukemia (AML) is a genetically heterogeneous myeloid malignancy that occurs more commonly in adults, and has an increasing incidence, most likely due to increasing age. Precise diagnostic classification of AML requires clinical and pathologic information, the latter including morphologic, immunophenotypic, cytogenetic and molecular genetic analysis. Risk stratification in AML requires cytogenetics evaluation as the most important predictor, with genetic mutations providing additional necessary information. AML with normal cytogenetics comprises about 40%-50% of all AML, and has been intensively investigated. The currently used 2008 World Health Organization classification of hematopoietic neoplasms has been proposed to be updated in 2016, also to include an update on the classification of AML, due to the continuously increasing application of genomic techniques that have led to major advances in our knowledge of the pathogenesis of AML. The purpose of this review is to describe some of these recent major advances in the diagnostic classification and risk stratification of AML. PMID:27144061

  13. Myeloid Leukemias and Virally Induced Lymphomas in Miniature Inbred Swine: Development of a Large Animal Tumor Model.

    PubMed

    Duran-Struuck, Raimon; Matar, Abraham J; Huang, Christene A

    2015-01-01

    The lack of a large animal transplantable tumor model has limited the study of novel therapeutic strategies for the treatment of liquid cancers. Swine as a species provide a natural option based on their similarities with humans and their already extensive use in biomedical research. Specifically, the Massachusetts General Hospital miniature swine herd retains unique genetic characteristics that facilitate the study of hematopoietic cell and solid organ transplantation. Spontaneously arising liquid cancers in these swine, specifically myeloid leukemias and B cell lymphomas, closely resemble human malignancies. The ability to establish aggressive tumor cell lines in vitro from these naturally occurring malignancies makes a transplantable tumor model a close reality. Here, we discuss our experience with myeloid and lymphoid tumors in major histocompatibility characterized miniature swine and future approaches regarding the development of a large animal transplantable tumor model. PMID:26635868

  14. Myeloid Leukemias and Virally Induced Lymphomas in Miniature Inbred Swine: Development of a Large Animal Tumor Model

    PubMed Central

    Duran-Struuck, Raimon; Matar, Abraham J.; Huang, Christene A.

    2015-01-01

    The lack of a large animal transplantable tumor model has limited the study of novel therapeutic strategies for the treatment of liquid cancers. Swine as a species provide a natural option based on their similarities with humans and their already extensive use in biomedical research. Specifically, the Massachusetts General Hospital miniature swine herd retains unique genetic characteristics that facilitate the study of hematopoietic cell and solid organ transplantation. Spontaneously arising liquid cancers in these swine, specifically myeloid leukemias and B cell lymphomas, closely resemble human malignancies. The ability to establish aggressive tumor cell lines in vitro from these naturally occurring malignancies makes a transplantable tumor model a close reality. Here, we discuss our experience with myeloid and lymphoid tumors in major histocompatibility characterized miniature swine and future approaches regarding the development of a large animal transplantable tumor model. PMID:26635868

  15. Olive leaf components apigenin 7-glucoside and luteolin 7-glucoside direct human hematopoietic stem cell differentiation towards erythroid lineage.

    PubMed

    Samet, Imen; Villareal, Myra O; Motojima, Hideko; Han, Junkyu; Sayadi, Sami; Isoda, Hiroko

    2015-06-01

    The generation of blood cellular components from hematopoietic stem cells is important for the therapy of a broad spectrum of hematological disorders. In recent years, several lines of evidence suggested that certain nutrients, vitamins and flavonoids may have important roles in controlling the stem cell fate decision by maintaining their self-renewal or stimulating the lineage-specific differentiation. In this study, main olive leaf phytochemicals oleuropein (Olp), apigenin 7-glucoside (Api7G) and luteolin 7-glucoside (Lut7G) were investigated for their potential effects on hematopoietic stem cell differentiation using both phenotypic and molecular analysis. Oleuropein and the combination of the three compounds enhanced the differentiation of CD34+ cells into myelomonocytic cells and lymphocytes progenitors and inhibited the commitment to megakaryocytic and erythroid lineages. Treatment with Lut7G stimulated both the erythroid and the myeloid differentiation, while treatment with Api7G specifically induced the differentiation of CD34+ cells towards the erythroid lineage and inhibited the myeloid differentiation. Erythroid differentiation induced by Api7G and Lut7G treatments was confirmed by the increase in hemoglobin genes expressions (α-hemoglobin, β-hemoglobin and γ-hemoglobin) and erythroid transcription factor GATA1 expression. As revealed by microarray analysis, the mechanisms underlying the erythroid differentiation-inducing effect of Api7G on hematopoietic stem cells involves the activation of JAK/STAT signaling pathway. These findings prove the differentiation-inducing effects of olive leaf compounds on hematopoietic stem cells and highlight their potential use in the ex vivo generation of blood cells. PMID:26299581

  16. Deregulated KLF4 Expression in Myeloid Leukemias Alters Cell Proliferation and Differentiation through MicroRNA and Gene Targets

    PubMed Central

    Morris, Valerie A.; Cummings, Carrie L.; Korb, Brendan; Boaglio, Sean

    2015-01-01

    Acute myeloid leukemia (AML) is characterized by increased proliferation and blocked differentiation of hematopoietic progenitors mediated, in part, by altered myeloid transcription factor expression. Decreased Krüppel-like factor 4 (KLF4) expression has been observed in AML, but how decreased KLF4 contributes to AML pathogenesis is largely unknown. We demonstrate decreased KLF4 expression in AML patient samples with various cytogenetic aberrations, confirm that KLF4 overexpression promotes myeloid differentiation and inhibits cell proliferation in AML cell lines, and identify new targets of KLF4. We have demonstrated that microRNA 150 (miR-150) expression is decreased in AML and that reintroducing miR-150 expression induces myeloid differentiation and inhibits proliferation of AML cells. We show that KLF family DNA binding sites are necessary for miR-150 promoter activity and that KLF2 or KLF4 overexpression induces miR-150 expression. miR-150 silencing, alone or in combination with silencing of CDKN1A, a well-described KLF4 target, did not fully reverse KLF4-mediated effects. Gene expression profiling and validation identified putative KLF4-regulated genes, including decreased MYC and downstream MYC-regulated gene expression in KLF4-overexpressing cells. Our findings indicate that decreased KLF4 expression mediates antileukemic effects through regulation of gene and microRNA networks, containing miR-150, CDKN1A, and MYC, and provide mechanistic support for therapeutic strategies increasing KLF4 expression. PMID:26644403

  17. A novel, myeloid transcription factor, C/EBP epsilon, is upregulated during granulocytic, but not monocytic, differentiation.

    PubMed

    Morosetti, R; Park, D J; Chumakov, A M; Grillier, I; Shiohara, M; Gombart, A F; Nakamaki, T; Weinberg, K; Koeffler, H P

    1997-10-01

    Human C/EBP epsilon is a newly cloned CCAAT/enhancer-binding transcription factor. Initial studies indicated it may be an important regulator of human myelopoiesis. To elucidate the range of expression of C/EBP epsilon, we used reverse transcription-polymerase chain reaction (RT-PCR) analysis and examined its expression in 28 hematopoietic and 14 nonhematopoietic cell lines, 16 fresh myeloid leukemia samples, and normal human hematopoietic stem cells and their mature progeny. Prominent expression of C/EBP epsilon mRNA occurred in the late myeloblastic and promyelocytic cell lines (NB4, HL60, GFD8), the myelomonoblastic cell lines (U937 and THP-1), the early myeloblast cell lines (ML1, KCL22, MDS92), and the T-cell lymphoblastic leukemia cell lines CEM and HSB-2. For the acute promyelocytic leukemia cell line NB4, C/EBP epsilon was the only C/EBP family member that was easily detected by RT-PCR. No C/EBP epsilon mRNA was found in erythroid, megakaryocyte, basophil, B lymphoid, or nonhematopoietic cell lines. Most acute myeloid leukemia samples (11 of 12) from patients expressed C/EBP epsilon. Northern blot and RT-PCR analyses showed that C/EBP epsilon mRNA decreased when the HL60 and KG-1 myeloblast cell lines were induced to differentiate toward macrophages. Similarly, Western blot analysis showed that expression of C/EBP epsilon protein was either unchanged or decreased slightly as the promyelocytic cell line NB4 differentiated down the macrophage-like pathway after treatment with a potent vitamin D3 analog (KH1060). In contrast, C/EBP epsilon protein levels increased dramatically as NB4 cells were induced to differentiate down the granulocytic pathway after exposure to 9-cis retinoic acid. Furthermore, very early, normal hematopoietic stem cells (CD34+/CD38-), purified from humans had very weak expression of C/EBP epsilon mRNA, but levels increased as these cells differentiated towards granulocytes. Likewise, purified granulocytes appeared to express higher

  18. [Neutrophil disorders: diagnosis and hematopoietic stem cell transplantation].

    PubMed

    Kobayashi, Masao

    2015-10-01

    Neutrophil disorders are classified into abnormal neutrophil function and granulopoiesis. The identification of genetic defects causing neutropenia and neutrophil dysfunction has revealed the mechanisms controlling myeloid differentiation and their functions. The International Union of Immunological Societies of Primary Immunodeficiencies represents the most current catalog of approximately 30 neutrophil disorders. In this report, we show the progress made in studies of the pathophysiology and treatment of these disorders, focusing on chronic granulomatous disease (CGD) and severe congenital neutropenia (SCN). Hematopoietic stem cell transplantation (HSCT) is the only available curative therapy for CGD and SCN. However, the use of HSCT as treatment for both diseases is limited by transplant-related mortality (TRM) because of active infections and intractable inflammatory complications. Recently, reduced-intensity conditioning regimens have been introduced to minimize the TRM and the late adverse effects of HSCT for both diseases. The results of HSCT using the RIC regimen for 40 patients with CGD and SCN in Hiroshima University Hospital are summarized herein. Determining the optimal line of treatment will require further accumulation to cases to refine HSCT for both diseases. PMID:26458464

  19. Inherited BCL10 deficiency impairs hematopoietic and nonhematopoietic immunity.

    PubMed

    Torres, Juan Manuel; Martinez-Barricarte, Rubén; García-Gómez, Sonia; Mazariegos, Marina S; Itan, Yuval; Boisson, Bertrand; Rholvarez, Rita; Jiménez-Reinoso, Anaïs; del Pino, Lucia; Rodríguez-Pena, Rebeca; Ferreira, Antonio; Hernández-Jiménez, Enrique; Toledano, Victor; Cubillos-Zapata, Carolina; Díaz-Almirón, Mariana; López-Collazo, Eduardo; Unzueta-Roch, José L; Sánchez-Ramón, Silvia; Regueiro, Jose R; López-Granados, Eduardo; Casanova, Jean-Laurent; Pérez de Diego, Rebeca

    2014-12-01

    Heterotrimers composed of B cell CLL/lymphoma 10 (BCL10), mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1), and caspase recruitment domain-containing (CARD) family adaptors play a role in NF-κB activation and have been shown to be involved in both the innate and the adaptive arms of immunity in murine models. Moreover, individuals with inherited defects of MALT1, CARD9, and CARD11 present with immunological and clinical phenotypes. Here, we characterized a case of autosomal-recessive, complete BCL10 deficiency in a child with a broad immunodeficiency, including defects of both hematopoietic and nonhematopoietic immunity. The patient died at 3 years of age and was homozygous for a loss-of-expression, loss-of-function BCL10 mutation. The effect of BCL10 deficiency was dependent on the signaling pathway, and, for some pathways, the cell type affected. Despite the noted similarities to BCL10 deficiency in mice, including a deficient adaptive immune response, human BCL10 deficiency in this patient resulted in a number of specific features within cell populations. Treatment of the patient's myeloid cells with a variety of pathogen-associated molecular pattern molecules (PAMPs) elicited a normal response; however, NF-κB-mediated fibroblast functions were dramatically impaired. The results of this study indicate that inherited BCL10 deficiency should be considered in patients with combined immunodeficiency with B cell, T cell, and fibroblast defects. PMID:25365219

  20. Inherited BCL10 deficiency impairs hematopoietic and nonhematopoietic immunity

    PubMed Central

    Torres, Juan Manuel; Martinez-Barricarte, Rubén; García-Gómez, Sonia; Mazariegos, Marina S.; Itan, Yuval; Boisson, Bertrand; ρlvarez, Rita; Jiménez-Reinoso, Anaïs; del Pino, Lucia; Rodríguez-Pena, Rebeca; Ferreira, Antonio; Hernández-Jiménez, Enrique; Toledano, Victor; Cubillos-Zapata, Carolina; Díaz-Almirón, Mariana; López-Collazo, Eduardo; Unzueta-Roch, José L.; Sánchez-Ramón, Silvia; Regueiro, Jose R.; López-Granados, Eduardo; Casanova, Jean-Laurent; Pérez de Diego, Rebeca

    2014-01-01

    Heterotrimers composed of B cell CLL/lymphoma 10 (BCL10), mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1), and caspase recruitment domain–containing (CARD) family adaptors play a role in NF-κB activation and have been shown to be involved in both the innate and the adaptive arms of immunity in murine models. Moreover, individuals with inherited defects of MALT1, CARD9, and CARD11 present with immunological and clinical phenotypes. Here, we characterized a case of autosomal-recessive, complete BCL10 deficiency in a child with a broad immunodeficiency, including defects of both hematopoietic and nonhematopoietic immunity. The patient died at 3 years of age and was homozygous for a loss-of-expression, loss-of-function BCL10 mutation. The effect of BCL10 deficiency was dependent on the signaling pathway, and, for some pathways, the cell type affected. Despite the noted similarities to BCL10 deficiency in mice, including a deficient adaptive immune response, human BCL10 deficiency in this patient resulted in a number of specific features within cell populations. Treatment of the patient’s myeloid cells with a variety of pathogen-associated molecular pattern molecules (PAMPs) elicited a normal response; however, NF-κB–mediated fibroblast functions were dramatically impaired. The results of this study indicate that inherited BCL10 deficiency should be considered in patients with combined immunodeficiency with B cell, T cell, and fibroblast defects. PMID:25365219

  1. Hematopoietic stem cells: an overview.

    PubMed

    Mosaad, Youssef Mohamed

    2014-12-01

    Considerable efforts have been made in recent years in understanding the mechanisms that govern hematopoietic stem cell (HSC) origin, development, differentiation, self-renewal, aging, trafficking, plasticity and transdifferentiation. Hematopoiesis occurs in sequential waves in distinct anatomical locations during development and these shifts in location are accompanied by changes in the functional status of the stem cells and reflect the changing needs of the developing organism. HSCs make a choice of either self-renewal or committing to differentiation. The balance between self-renewal and differentiation is considered to be critical to the maintenance of stem cell numbers. It is still under debate if HSC can rejuvenate infinitely or if they do not possess ''true" self-renewal and undergo replicative senescence such as any other somatic cell. Gene therapy applications that target HSCs offer a great potential for the treatment of hematologic and immunologic diseases. However, the clinical success has been limited by many factors. This review is intended to summarize the recent advances made in the human HSC field, and will review the hematopoietic stem cell from definition through development to clinical applications. PMID:25457002

  2. The histone H2A deubiquitinase Usp16 regulates hematopoiesis and hematopoietic stem cell function

    PubMed Central

    Gu, Yue; Jones, Amanda E.; Yang, Wei; Liu, Shanrun; Dai, Qian; Liu, Yudong; Swindle, C. Scott; Zhou, Dewang; Zhang, Zhuo; Ryan, Thomas M.; Townes, Tim M.; Klug, Christopher A.; Chen, Dongquan; Wang, Hengbin

    2016-01-01

    Epigenetic mechanisms play important regulatory roles in hematopoiesis and hematopoietic stem cell (HSC) function. Subunits of polycomb repressive complex 1 (PRC1), the major histone H2A ubiquitin ligase, are critical for both normal and pathological hematopoiesis; however, it is unclear which of the several counteracting H2A deubiquitinases functions along with PRC1 to control H2A ubiquitination (ubH2A) level and regulates hematopoiesis in vivo. Here we investigated the function of Usp16 in mouse hematopoiesis. Conditional deletion of Usp16 in bone marrow resulted in a significant increase of global ubH2A level and lethality. Usp16 deletion did not change HSC number but was associated with a dramatic reduction of mature and progenitor cell populations, revealing a role in governing HSC lineage commitment. ChIP- and RNA-sequencing studies in HSC and progenitor cells revealed that Usp16 bound to many important hematopoietic regulators and that Usp16 deletion altered the expression of genes in transcription/chromosome organization, immune response, hematopoietic/lymphoid organ development, and myeloid/leukocyte differentiation. The altered gene expression was partly rescued by knockdown of PRC1 subunits, suggesting that Usp16 and PRC1 counterbalance each other to regulate cellular ubH2A level and gene expression in the hematopoietic system. We further discovered that knocking down Cdkn1a (p21cip1), a Usp16 target and regulated gene, rescued the altered cell cycle profile and differentiation defect of Usp16-deleted HSCs. Collectively, these studies identified Usp16 as one of the histone H2A deubiquitinases, which coordinates with the H2A ubiquitin ligase PRC1 to regulate hematopoiesis, and revealed cell cycle regulation by Usp16 as key for HSC differentiation. PMID:26699484

  3. The histone H2A deubiquitinase Usp16 regulates hematopoiesis and hematopoietic stem cell function.

    PubMed

    Gu, Yue; Jones, Amanda E; Yang, Wei; Liu, Shanrun; Dai, Qian; Liu, Yudong; Swindle, C Scott; Zhou, Dewang; Zhang, Zhuo; Ryan, Thomas M; Townes, Tim M; Klug, Christopher A; Chen, Dongquan; Wang, Hengbin

    2016-01-01

    Epigenetic mechanisms play important regulatory roles in hematopoiesis and hematopoietic stem cell (HSC) function. Subunits of polycomb repressive complex 1 (PRC1), the major histone H2A ubiquitin ligase, are critical for both normal and pathological hematopoiesis; however, it is unclear which of the several counteracting H2A deubiquitinases functions along with PRC1 to control H2A ubiquitination (ubH2A) level and regulates hematopoiesis in vivo. Here we investigated the function of Usp16 in mouse hematopoiesis. Conditional deletion of Usp16 in bone marrow resulted in a significant increase of global ubH2A level and lethality. Usp16 deletion did not change HSC number but was associated with a dramatic reduction of mature and progenitor cell populations, revealing a role in governing HSC lineage commitment. ChIP- and RNA-sequencing studies in HSC and progenitor cells revealed that Usp16 bound to many important hematopoietic regulators and that Usp16 deletion altered the expression of genes in transcription/chromosome organization, immune response, hematopoietic/lymphoid organ development, and myeloid/leukocyte differentiation. The altered gene expression was partly rescued by knockdown of PRC1 subunits, suggesting that Usp16 and PRC1 counterbalance each other to regulate cellular ubH2A level and gene expression in the hematopoietic system. We further discovered that knocking down Cdkn1a (p21cip1), a Usp16 target and regulated gene, rescued the altered cell cycle profile and differentiation defect of Usp16-deleted HSCs. Collectively, these studies identified Usp16 as one of the histone H2A deubiquitinases, which coordinates with the H2A ubiquitin ligase PRC1 to regulate hematopoiesis, and revealed cell cycle regulation by Usp16 as key for HSC differentiation. PMID:26699484

  4. Human Olfactory Mucosa Multipotent Mesenchymal Stromal Cells Promote Survival, Proliferation, and Differentiation of Human Hematopoietic Cells

    PubMed Central

    Diaz-Solano, Dylana; Wittig, Olga; Ayala-Grosso, Carlos; Pieruzzini, Rosalinda

    2012-01-01

    Multipotent mesenchymal stromal cells (MSCs) from the human olfactory mucosa (OM) are cells that have been proposed as a niche for neural progenitors. OM-MSCs share phenotypic and functional properties with bone marrow (BM) MSCs, which constitute fundamental components of the hematopoietic niche. In this work, we investigated whether human OM-MSCs may promote the survival, proliferation, and differentiation of human hematopoietic stem cells (HSCs). For this purpose, human bone marrow cells (BMCs) were co-cultured with OM-MSCs in the absence of exogenous cytokines. At different intervals, nonadherent cells (NACs) were harvested from BMC/OM-MSC co-cultures, and examined for the expression of blood cell markers by flow cytometry. OM-MSCs supported the survival (cell viability >90%) and proliferation of BMCs, after 54 days of co-culture. At 20 days of co-culture, flow cytometric and microscopic analyses showed a high percentage (73%) of cells expressing the pan-leukocyte marker CD45, and the presence of cells of myeloid origin, including polymorphonuclear leukocytes, monocytes, basophils, eosinophils, erythroid cells, and megakaryocytes. Likewise, T (CD3), B (CD19), and NK (CD56/CD16) cells were detected in the NAC fraction. Colony-forming unit–granulocyte/macrophage (CFU-GM) progenitors and CD34+ cells were found, at 43 days of co-culture. Reverse transcriptase–polymerase chain reaction (RT-PCR) studies showed that OM-MSCs constitutively express early and late-acting hematopoietic cytokines (i.e., stem cell factor [SCF] and granulocyte- macrophage colony-stimulating factor [GM-CSF]). These results constitute the first evidence that OM-MSCs may provide an in vitro microenvironment for HSCs. The capacity of OM-MSCs to support the survival and differentiation of HSCs may be related with the capacity of OM-MSCs to produce hematopoietic cytokines. PMID:22471939

  5. Hematopoietic Stem Cell Origin of BRAFV600E Mutations in Hairy Cell Leukemia

    PubMed Central

    Chung, Young Rock; Lito, Piro; Teruya-Feldstein, Julie; Hu, Wenhuo; Beguelin, Wendy; Monette, Sebastien; Duy, Cihangir; Rampal, Raajit; Telis, Leon; Patel, Minal; Kim, Min Kyung; Huberman, Kety; Bouvier, Nancy; Berger, Michael F.; Melnick, Ari M.; Rosen, Neal; Tallman, Martin S.

    2014-01-01

    Hairy cell leukemia (HCL) is a chronic lymphoproliferative disorder characterized by somatic BRAFV600E mutations. The malignant cell in HCL has immunophenotypic features of a mature B cell, but no normal counterpart along the continuum of developing B lymphocytes has been delineated as the cell of origin. We find that the BRAFV600E mutation is present in hematopoietic stem cells (HSCs) in HCL patients, and that these patients exhibit marked alterations in hematopoietic stem/progenitor cell (HSPC) frequencies. Quantitative sequencing analysis revealed a mean BRAFV600E-mutant allele frequency of 4.97% in HSCs from HCL patients. Moreover, transplantation of BRAFV600E-mutant HSCs from an HCL patient into immunodeficient mice resulted in stable engraftment of BRAFV600E-mutant human hematopoietic cells, revealing the functional self-renewal capacity of HCL HSCs. Consistent with the human genetic data, expression of BRafV600E in murine HSPCs resulted in a lethal hematopoietic disorder characterized by splenomegaly, anemia, thrombocytopenia, increased circulating soluble CD25, and increased clonogenic capacity of B lineage cells—all classic features of human HCL. In contrast, restricting expression of BRafV600E to the mature B cell compartment did not result in disease. Treatment of HCL patients with vemurafenib, an inhibitor of mutated BRAF, resulted in normalization of HSPC frequencies and increased myeloid and erythroid output from HSPCs. These findings link the pathogenesis of HCL to somatic mutations that arise in HSPCs and further suggest that chronic lymphoid malignancies may be initiated by aberrant HSCs. PMID:24871132

  6. Hematopoietic effects of benzene inhalation assessed by long-term bone marrow culture

    SciTech Connect

    Abraham, N.G.

    1996-12-01

    The strong and long-lasting hematotoxic effect after benzene exposure in vivo (300 ppm, 6 hr/day, 5 days/week for 2 weeks) was assessed in mice with bone marrow cells grown in long-term bone marrow culture (LTBMC). Bone marrow cultures initiated 1 day after the last benzene exposure did not produce adequate numbers of hematopoietic cells over 3 weeks and, in most cases, no erythroid or myeloid clonogenic cells could be recovered. The adherent cell layer of these cultures had a lower capacity for supporting in vitro hematopoiesis after the second seeding with normal bone marrow cells compared with control cultures. Two weeks after the last benzene exposure, body weight, hematocrit, bone marrow cellularity, and committed hematopoietic progenitor content (BFU-E and CFU-GM) were regenerated to normal or subnormal values, whereas hematopoiesis in LTB MC was very poor. Over 8 weeks, little or no significant committed progenitor production was observed. Treatment of mice exposed to benzene with hemin (three doses of 3 {mu}g/g bw iv over 2 weeks for a total dose of 9 {mu}g/g) partially overcame the toxic effect of benzene on the hematopoietic system as measured by the LTBMC method. Cultures from mice treated with hemin had a modest recovery of BFU-E and CFU-GM clonogenic potential after 5 to 6 weeks in LTBMC. In contrast, little or no recovery was obtained for the adherent cell layer clonogenic capacity, even after hemin treatment. These results clearly indicate a strong, long-lasting toxic effect on the bone marrow stroma and a limited recovery of hematopoietic potential by clonogenic cells of the nonadherent population after in vivo hemin treatment. 35 refs., 3 figs., 1 tab.

  7. New approaches for the immunotherapy of Acute Myeloid Leukemia

    PubMed Central

    Geiger, Terrence L.; Rubnitz, Jeffrey E.

    2015-01-01

    Acute Myeloid Leukemia (AML) is a set of related diseases characterized by the immortalization and uncontrolled expansion of myeloid precursors. Core therapy for AML has remained unchanged for nearly 30 years, and survival rates remain unsatisfactory. However, advances in the immunotherapy of AML have created opportunities for improved outcomes. Enforcing a tumor-specific immune response through the re-direction of the adaptive immune system, which links remarkable specificity with potent cytotoxic effector functions, has proven particularly compelling. This may be coupled with immune checkpoint blockade and conventional therapies for optimal effect. Engineered antibodies are currently in use in AML and the repertoire of available therapeutics will expand. NK cells have shown effectiveness in this disease. New methods to optimize the targeting and activation of AML cells show potential. Most significantly, adoptive immunotherapy with tumor-specific T cells, and particularly T cells re-directed using genetically introduced TCR or chimeric antigen receptors, have particular promise. Each of these approaches has unique benefits and challenges that we explore in this review. PMID:25977190

  8. An overview of chronic myeloid leukemia and its animal models.

    PubMed

    Ma, WeiXu; Ma, Ning; Chen, XiaoHui; Zhang, YiYue; Zhang, WenQing

    2015-12-01

    Chronic myeloid leukemia (CML) is a form of leukemia characterized by the presence of clonal bone marrow stem cells with the proliferation of mature granulocytes (neutrophils, eosinophils, and basophils) and their precursors. CML is a type of myeloproliferative disease associated with a characteristic chromosomal translocation called the Philadelphia (Ph) chromosome or t (9;22) translocation (BCR-ABL). CML is now usually treated with targeted drugs called tyrosine kinase inhibitors (TKIs). The mechanism and natural history of CML is still unclear. Here, we summarize the present CML animal disease models and compare them with each other. Meanwhile, we propose that it is a very wise choice to establish zebrafish (Danio rerio) CML model mimics clinical CML. This model could be used to learn more about the mechanism of CML, and to aid in the development of new drugs to treat CML. PMID:26582013

  9. Clostridium difficile infection in Chilean patients submitted to hematopoietic stem cell transplantation

    PubMed Central

    Pilcante, Javier; Rojas, Patricio; Ernst, Daniel; Sarmiento, Mauricio; Ocqueteau, Mauricio; Bertin, Pablo; García, Maria; Rodriguez, Maria; Jara, Veronica; Ajenjo, Maria; Ramirez, Pablo

    2015-01-01

    Introduction Patients submitted to hematopoietic stem cell transplantation have an increased risk of Clostridium difficile infection and multiple risk factors have been identified. Published reports have indicated an incidence from 9% to 30% of transplant patients however to date there is no information about infection in these patients in Chile. Methods A retrospective analysis was performed of patients who developed C. difficile infection after hematopoietic stem cell transplantations from 2000 to 2013. Statistical analysis used the Statistical Package for the Social Sciences software. Results Two hundred and fifty patients were studied (mean age: 39 years; range: 17–69), with 147 (59%) receiving allogeneic transplants and 103 (41%) receiving autologous transplants. One hundred and ninety-two (77%) patients had diarrhea, with 25 (10%) cases of C. difficile infection being confirmed. Twenty infected patients had undergone allogeneic transplants, of which ten had acute lymphoblastic leukemia, three had acute myeloid leukemia and seven had other diseases (myelodysplastic syndrome, chronic myeloid leukemia, severe aplastic anemia). In the autologous transplant group, five patients had C. difficile infection; two had multiple myeloma, one had amyloidosis, one had acute myeloid leukemia and one had germinal carcinoma. The overall incidence of C. difficile infection was 4% within the first week, 6.4% in the first month and 10% in one year, with no difference in overall survival between infected and non-infected groups (72.0% vs. 67.6%, respectively; p-value = 0.56). Patients infected after allogeneic transplants had a slower time to neutrophil engraftment compared to non-infected patients (17.5 vs. 14.9 days, respectively; p-value = 0.008). In the autologous transplant group there was no significant difference in the neutrophil engraftment time between infected and non-infected patients (12.5 days vs. 11.8 days, respectively; p-value = 0.71). In the allogeneic

  10. Acute Myeloid Leukemia and Myelodysplastic Syndromes in Older Adults

    PubMed Central

    Klepin, Heidi D.; Rao, Arati V.; Pardee, Timothy S.

    2014-01-01

    Treatment of older adults with acute myeloid leukemia (AML) or myelodysplastic syndromes (MDS) is challenging because of disease morbidity and associated treatments. Both diseases represent a genetically heterogeneous group of disorders primarily affecting older adults, with treatment strategies ranging from supportive care to hematopoietic stem-cell transplantation. Although selected older adults can benefit from intensive therapies, as a group they experience increased treatment-related morbidity, are more likely to relapse, and have decreased survival. Age-related outcome disparities are attributed to both tumor and patient characteristics, requiring an individualized approach to treatment decision making beyond consideration of chronologic age alone. Selection of therapy for any individual requires consideration of both disease-specific risk factors and estimates of treatment tolerance and life expectancy derived from evaluation of functional status and comorbidity. Although treatment options for older adults are expanding, clinical trials accounting for the heterogeneity of tumor biology and aging are needed to define standard-of-care treatments for both disease groups. In addition, trials should include outcomes addressing quality of life, maintenance of independence, and use of health care services to assist in patient-centered decision making. This review will highlight available evidence in treatment of older adults with AML or MDS and unanswered clinical questions for older adults with these diseases. PMID:25071138

  11. Myeloid suppressor cells and immune modulation in lung cancer

    PubMed Central

    Srivastava, Minu K.; Andersson, Åsa; Zhu, Li; Harris-White, Marni; Lee, Jay M.; Dubinett, Steven; Sharma, Sherven

    2012-01-01

    Many tumors, including lung cancers, promote immune tolerance to escape host immune surveillance and facilitate tumor growth. Tumors utilize numerous pathways to inhibit immune responses, including the elaboration of immune-suppressive mediators such as PGE2, TGF-β, IL-10, VEGF, GM-CSF, IL-6, S100A8/A9 and SCF, which recruit and/or activate myeloid-derived suppressor cells (MDSCs). MDSCs, a subset of heterogeneous bone marrow-derived hematopoietic cells, are found in the peripheral blood of cancer patients and positively correlate to malignancy. Solid tumors contain MDSCs that maintain an immune-suppressive network in the tumor microenvironment. This review will focus on the interaction of tumors with MDSCs that lead to dysregulation of antigen presentation and T-cell activities in murine tumor models. Specific genetic signatures in lung cancer modulate the activities of MDSCs and impact tumor progression. Targeting MDSCs may have a long-term antitumor benefit and is at the forefront of anticancer therapeutic strategies. PMID:22401635

  12. Sex differences in the incidence of chronic myeloid leukemia.

    PubMed

    Radivoyevitch, Tomas; Jankovic, Gradimir M; Tiu, Ramon V; Saunthararajah, Yogen; Jackson, Robert C; Hlatky, Lynn R; Gale, Robert Peter; Sachs, Rainer K

    2014-03-01

    The incidence of chronic myeloid leukemia (CML), which is caused by BCR/ABL chimeric oncogene formation in a pluripotent hematopoietic stem cell (HSC), increases with age and exposure to ionizing radiation. CML is a comparatively well-characterized neoplasm, important for its own sake and useful for insights into other neoplasms. Here, Surveillance, Epidemiology and End Results (SEER) CML data are analyzed after considering possible misclassification of chronic myelo-monocytic leukemia as CML. For people older than 25 years, plots of male and female CML log incidences versus age at diagnosis are approximately parallel straight lines with males either above or to the left of females. This is consistent with males having a higher risk of developing CML or a shorter latency from initiation to diagnosis of CML. These distinct mechanisms cannot be distinguished using SEER data alone. Therefore, CML risks among male and female Japanese A-bomb survivors are also analyzed. The present analyses suggest that sex differences in CML incidence more likely result from differences in risk than in latency. The simplest but not the sole interpretation of this is that males have more target cells at risk to develop CML. Comprehensive mathematical models of CML could lead to a better understanding of the role of HSCs in CML and other preleukemias that can progress to acute leukemia. PMID:24337217

  13. An update of current treatments for adult acute myeloid leukemia

    PubMed Central

    Gardin, Claude

    2016-01-01

    Recent advances in acute myeloid leukemia (AML) biology and its genetic landscape should ultimately lead to more subset-specific AML therapies, ideally tailored to each patient's disease. Although a growing number of distinct AML subsets have been increasingly characterized, patient management has remained disappointingly uniform. If one excludes acute promyelocytic leukemia, current AML management still relies largely on intensive chemotherapy and allogeneic hematopoietic stem cell transplantation (HSCT), at least in younger patients who can tolerate such intensive treatments. Nevertheless, progress has been made, notably in terms of standard drug dose intensification and safer allogeneic HSCT procedures, allowing a larger proportion of patients to achieve durable remission. In addition, improved identification of patients at relatively low risk of relapse should limit their undue exposure to the risks of HSCT in first remission. The role of new effective agents, such as purine analogs or gemtuzumab ozogamicin, is still under investigation, whereas promising new targeted agents are under clinical development. In contrast, minimal advances have been made for patients unable to tolerate intensive treatment, mostly representing older patients. The availability of hypomethylating agents likely represents an encouraging first step for this latter population, and it is hoped will allow for more efficient combinations with novel agents. PMID:26660429

  14. Differential regulation of myeloid leukemias by the bone marrow microenvironment.

    PubMed

    Krause, Daniela S; Fulzele, Keertik; Catic, André; Sun, Chia Chi; Dombkowski, David; Hurley, Michael P; Lezeau, Sanon; Attar, Eyal; Wu, Joy Y; Lin, Herbert Y; Divieti-Pajevic, Paola; Hasserjian, Robert P; Schipani, Ernestina; Van Etten, Richard A; Scadden, David T

    2013-11-01

    Like their normal hematopoietic stem cell counterparts, leukemia stem cells (LSCs) in chronic myelogenous leukemia (CML) and acute myeloid leukemia (AML) are presumed to reside in specific niches in the bone marrow microenvironment (BMM) and may be the cause of relapse following chemotherapy. Targeting the niche is a new strategy to eliminate persistent and drug-resistant LSCs. CD44 (refs. 3,4) and interleukin-6 (ref. 5) have been implicated previously in the LSC niche. Transforming growth factor-β1 (TGF-β1) is released during bone remodeling and plays a part in maintenance of CML LSCs, but a role for TGF-β1 from the BMM has not been defined. Here, we show that alteration of the BMM by osteoblastic cell-specific activation of the parathyroid hormone (PTH) receptor attenuates BCR-ABL1 oncogene-induced CML-like myeloproliferative neoplasia (MPN) but enhances MLL-AF9 oncogene-induced AML in mouse transplantation models, possibly through opposing effects of increased TGF-β1 on the respective LSCs. PTH treatment caused a 15-fold decrease in LSCs in wild-type mice with CML-like MPN and reduced engraftment of immune-deficient mice with primary human CML cells. These results demonstrate that LSC niches in CML and AML are distinct and suggest that modulation of the BMM by PTH may be a feasible strategy to reduce LSCs, a prerequisite for the cure of CML. PMID:24162813

  15. Hsp90 Inhibitors for the Treatment of Chronic Myeloid Leukemia

    PubMed Central

    Khajapeer, Kalubai Vari; Baskaran, Rajasekaran

    2015-01-01

    Chronic myeloid leukemia (CML) is a hematological malignancy that arises due to reciprocal translocation of 3′ sequences from c-Abelson (ABL) protooncogene of chromosome 9 with 5′ sequence of truncated break point cluster region (BCR) on chromosome 22. BCR-ABL is a functional oncoprotein p210 that exhibits constitutively activated tyrosine kinase causing genomic alteration of hematopoietic stem cells. BCR-ABL specific tyrosine kinase inhibitors (TKIs) successfully block CML progression. However, drug resistance owing to BCR-ABL mutations and overexpression is still an issue. Heat-shock proteins (Hsps) function as molecular chaperones facilitating proper folding of nascent polypeptides. Their increased expression under stressful conditions protects cells by stabilizing unfolded or misfolded peptides. Hsp90 is the major mammalian protein and is required by BCR-ABL for stabilization and maturation. Hsp90 inhibitors destabilize the binding of BCR-ABL protein thus leading to the formation of heteroprotein complex that is eventually degraded by the ubiquitin-proteasome pathway. Results of many novel Hsp90 inhibitors that have entered into various clinical trials are encouraging. The present review targets the current development in the CML treatment by availing Hsp90 specific inhibitors. PMID:26770832

  16. Sex differences in the incidence of chronic myeloid leukemia

    PubMed Central

    Jankovic, Gradimir M.; Tiu, Ramon V.; Saunthararajah, Yogen; Jackson, Robert C.; Hlatky, Lynn R.; Gale, Robert Peter; Sachs, Rainer K.

    2014-01-01

    The incidence of chronic myeloid leukemia (CML), which is caused by BCR/ABL chimeric oncogene formation in a pluripotent hematopoietic stem cell (HSC), increases with age and exposure to ionizing radiation. CML is a comparatively well-characterized neoplasm, important for its own sake and useful for insights into other neoplasms. Here, Surveillance, Epidemiology and End Results (SEER) CML data are analyzed after considering possible misclassification of chronic myelo-monocytic leukemia as CML. For people older than 25 years, plots of male and female CML log incidences versus age at diagnosis are approximately parallel straight lines with males either above or to the left of females. This is consistent with males having a higher risk of developing CML or a shorter latency from initiation to diagnosis of CML. These distinct mechanisms cannot be distinguished using SEER data alone. Therefore, CML risks among male and female Japanese A-bomb survivors are also analyzed. The present analyses suggest that sex differences in CML incidence more likely result from differences in risk than in latency. The simplest but not the sole interpretation of this is that males have more target cells at risk to develop CML. Comprehensive mathematical models of CML could lead to a better understanding of the role of HSCs in CML and other preleukemias that can progress to acute leukemia. PMID:24337217

  17. Prognosis of patients with core binding factor acute myeloid leukemia after first relapse

    PubMed Central

    Kurosawa, Saiko; Miyawaki, Shuichi; Yamaguchi, Takuhiro; Kanamori, Heiwa; Sakura, Toru; Moriuchi, Yukiyoshi; Sano, Fumiaki; Kobayashi, Takeshi; Yasumoto, Atsushi; Hatanaka, Kazuo; Yanada, Masamitsu; Nawa, Yuichiro; Takeuchi, Jin; Nakamura, Yukinori; Fujisawa, Shin; Shibayama, Hirohiko; Miura, Ikuo; Fukuda, Takahiro

    2013-01-01

    Core binding factor acute myeloid leukemia is known to have a favorable prognosis, however, there have been no detailed analyses on prognostic factors after first relapse. Using a nationwide database, we retrospectively analyzed core binding factor acute myeloid leukemia patients who relapsed after being treated with chemotherapy alone during their first complete remission. Of a total of 397 patients who were diagnosed with core binding factor acute myeloid leukemia, 208 experienced a first relapse, and analyses were performed in 139 patients for whom additional data were available. In the entire cohort, the overall survival rate after relapse was 48% at 3 years. By multivariate analysis, younger age at diagnosis, a longer interval before relapse, and inv(16) were shown to be independently associated with better survival after relapse. Although there was no significant difference in survival after relapse between patients who underwent allogeneic hematopoietic cell transplantation and those who did not in the overall series of relapsed patients, we found that transplantation significantly improved survival among patients who had t(8;21) (54% versus 26% at 3 years, P=0.002). In addition, among patients with t(8;21), those who had different cytogenetics at relapse had a significantly improved survival after transplantation, while those who had same cytogenetics did not. We showed that the prognosis differs significantly and optimal treatment strategies may vary between groups of patients with core binding factor acute myeloid leukemia with different cytogenetic profiles at relapse. These findings may help to guide therapeutic decisions after first relapse. PMID:23716553

  18. Acute Myeloid Leukemia with Isolated Trisomy 19 Associated with Diffuse Myelofibrosis and Osteosclerosis

    PubMed Central

    Stelling, Adam; Jonas, Brian A.; Rashidi, Hooman H.; Abedi, Mehrdad; Chen, Mingyi

    2015-01-01

    Primary myelofibrosis (PMF), per WHO criteria, is a clonal myeloproliferative neoplasm that usually presents with a proliferation of granulocytic and megakaryocytic lineages with an associated fibrous deposition and extramedullary hematopoiesis. The bone marrow histologic findings of this disorder are typically characterized by the presence of myeloid metaplasia with an associated reactive fibrosis, angiogenesis, and osteosclerosis. However, marked myelofibrosis is not solely confined to PMF and may also be associated with other conditions including but not limited to acute megakaryoblastic leukemias (FAB AML-M7). Here, we describe a rare case of a non-megakaryoblastic acute myeloid leukemia with marked myelofibrosis with osteosclerosis and an isolated trisomy 19. A 19-year-old male presented with severe bone pain of one week duration with a complete blood cell count and peripheral smear showing a mild anemia and occasional circulating blasts. A follow up computed tomography (CT) scan showed diffuse osteosclerosis with no evidence of hepatosplenomegaly or lymphadenopathy. Subsequently, the bone marrow biopsy showed markedly sclerotic bony trabeculae and a hypercellular marrow with marked fibrosis and intervening sheets of immature myeloid cells consistent with myeloblasts with monocytic differentiation. Importantly, these myeloblasts were negative for megakaryocytic markers (CD61 and vWF), erythroid markers (hemoglobin and E-cadherin), and lymphoid markers (CD3, CD19, and TdT). Metaphase cytogenetics showed an isolated triosomy 19 with no JAK2 V617F mutation. The patient was treated with induction chemotherapy followed by allogenic hematopoietic stem cell transplantation which subsequently resulted in a rapid resolution of bone marrow fibrosis, suggesting graft-anti-fibrosis effect. This is a rare case of a non-megakaryoblastic acute myeloid leukemia with myelofibrosis and osteosclerosis with trisomy 19 that may provide insights into the prognosis and therapeutic

  19. Tipifarnib in Treating Older Patients With Acute Myeloid Leukemia

    ClinicalTrials.gov

    2015-03-19

    Adult Acute Megakaryoblastic Leukemia; Adult Acute Monoblastic Leukemia; Adult Acute Monocytic Leukemia; Adult Acute Myeloid Leukemia With Inv(16)(p13.1q22); CBFB-MYH11; Adult Acute Myeloid Leukemia With Maturation; Adult Acute Myeloid Leukemia With Minimal Differentiation; Adult Acute Myeloid Leukemia With t(16;16)(p13.1;q22); CBFB-MYH11; Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); RUNX1-RUNX1T1; Adult Acute Myeloid Leukemia With t(9;11)(p22;q23); MLLT3-MLL; Adult Acute Myeloid Leukemia Without Maturation; Adult Acute Myelomonocytic Leukemia; Adult Erythroleukemia; Adult Pure Erythroid Leukemia; Alkylating Agent-Related Acute Myeloid Leukemia; Secondary Acute Myeloid Leukemia; Untreated Adult Acute Myeloid Leukemia

  20. Endothelium and NOTCH specify and amplify aorta-gonad-mesonephros-derived hematopoietic stem cells.

    PubMed

    Hadland, Brandon K; Varnum-Finney, Barbara; Poulos, Michael G; Moon, Randall T; Butler, Jason M; Rafii, Shahin; Bernstein, Irwin D

    2015-05-01

    Hematopoietic stem cells (HSCs) first emerge during embryonic development within vessels such as the dorsal aorta of the aorta-gonad-mesonephros (AGM) region, suggesting that signals from the vascular microenvironment are critical for HSC development. Here, we demonstrated that AGM-derived endothelial cells (ECs) engineered to constitutively express AKT (AGM AKT-ECs) can provide an in vitro niche that recapitulates embryonic HSC specification and amplification. Specifically, nonengrafting embryonic precursors, including the VE-cadherin-expressing population that lacks hematopoietic surface markers, cocultured with AGM AKT-ECs specified into long-term, adult-engrafting HSCs, establishing that a vascular niche is sufficient to induce the endothelial-to-HSC transition in vitro. Subsequent to hematopoietic induction, coculture with AGM AKT-ECs also substantially increased the numbers of HSCs derived from VE-cadherin⁺CD45⁺ AGM hematopoietic cells, consistent with a role in supporting further HSC maturation and self-renewal. We also identified conditions that included NOTCH activation with an immobilized NOTCH ligand that were sufficient to amplify AGM-derived HSCs following their specification in the absence of AGM AKT-ECs. Together, these studies begin to define the critical niche components and resident signals required for HSC induction and self-renewal ex vivo, and thus provide insight for development of defined in vitro systems targeted toward HSC generation for therapeutic applications. PMID:25866967

  1. Parasitic Infections in Hematopoietic Stem Cell Transplantation

    PubMed Central

    Jarque, Isidro; Salavert, Miguel; Pemán, Javier

    2016-01-01

    Parasitic infections are rarely documented in hematopoietic stem cell transplant recipients. However they may be responsible for fatal complications that are only diagnosed at autopsy. Increased awareness of the possibility of parasitic diseases both in autologous and allogeneic stem cell transplant patients is relevant not only for implementing preventive measures but also for performing an early diagnosis and starting appropriate therapy for these unrecognized but fatal infectious complications in hematopoietic transplant recipients. In this review, we will focus on parasitic diseases occurring in this population especially those with major clinical relevance including toxoplasmosis, American trypanosomiasis, leishmaniasis, malaria, and strongyloidiasis, among others, highlighting the diagnosis and management in hematopoietic transplant recipients. PMID:27413527

  2. Parasitic Infections in Hematopoietic Stem Cell Transplantation.

    PubMed

    Jarque, Isidro; Salavert, Miguel; Pemán, Javier

    2016-01-01

    Parasitic infections are rarely documented in hematopoietic stem cell transplant recipients. However they may be responsible for fatal complications that are only diagnosed at autopsy. Increased awareness of the possibility of parasitic diseases both in autologous and allogeneic stem cell transplant patients is relevant not only for implementing preventive measures but also for performing an early diagnosis and starting appropriate therapy for these unrecognized but fatal infectious complications in hematopoietic transplant recipients. In this review, we will focus on parasitic diseases occurring in this population especially those with major clinical relevance including toxoplasmosis, American trypanosomiasis, leishmaniasis, malaria, and strongyloidiasis, among others, highlighting the diagnosis and management in hematopoietic transplant recipients. PMID:27413527

  3. Delineation of Natural Killer Cell Differentiation from Myeloid Progenitors in Human

    PubMed Central

    Chen, Qingfeng; Ye, Weijian; Jian Tan, Wei; Mei Yong, Kylie Su; Liu, Min; Qi Tan, Shu; Loh, Eva; TE Chang, Kenneth; Chye Tan, Thiam; Preiser, Peter R.; Chen, Jianzhu

    2015-01-01

    Understanding of natural killer (NK) cell development in human is incomplete partly because of limited access to appropriate human tissues. We have developed a cytokine-enhanced humanized mouse model with greatly improved reconstitution and function of human NK cells. Here we report the presence of a cell population in the bone marrow of the cytokine-treated humanized mice that express both NK cell marker CD56 and myeloid markers such as CD36 and CD33. The CD56+CD33+CD36+ cells are also found in human cord blood, fetal and adult bone marrow. Although the CD56+CD33+CD36+ cells do not express the common NK cell functional receptors and exhibit little cytotoxic and cytokine-producing activities, they readily differentiate into mature NK cells by acquiring expression of NK cell receptors and losing expression of the myeloid markers. Further studies show that CD33+CD36+ myeloid NK precursors are derived from granulo-myelomonocytic progenitors. These results delineate the pathway of human NK cell differentiation from myeloid progenitors in the bone marrow and suggest the utility of humanized mice for studying human hematopoiesis. PMID:26456148

  4. Technical Advance: Transcription factor, promoter, and enhancer utilization in human myeloid cells

    PubMed Central

    Joshi, Anagha; Pooley, Christopher; Freeman, Tom C.; Lennartsson, Andreas; Babina, Magda; Schmidl, Christian; Geijtenbeek, Teunis; Michoel, Tom; Severin, Jessica; Itoh, Masayoshi; Lassmann, Timo; Kawaji, Hideya; Hayashizaki, Yoshihide; Carninci, Piero; Forrest, Alistair R. R.; Rehli, Michael; Hume, David A.

    2015-01-01

    The generation of myeloid cells from their progenitors is regulated at the level of transcription by combinatorial control of key transcription factors influencing cell-fate choice. To unravel the global dynamics of this process at the transcript level, we generated transcription profiles for 91 human cell types of myeloid origin by use of CAGE profiling. The CAGE sequencing of these samples has allowed us to investigate diverse aspects of transcription control during myelopoiesis, such as identification of novel transcription factors, miRNAs, and noncoding RNAs specific to the myeloid lineage. We further reconstructed a transcription regulatory network by clustering coexpressed transcripts and associating them with enriched cis-regulatory motifs. With the use of the bidirectional expression as a proxy for enhancers, we predicted over 2000 novel enhancers, including an enhancer 38 kb downstream of IRF8 and an intronic enhancer in the KIT gene locus. Finally, we highlighted relevance of these data to dissect transcription dynamics during progressive maturation of granulocyte precursors. A multifaceted analysis of the myeloid transcriptome is made available (www.myeloidome.roslin.ed.ac.uk). This high-quality dataset provides a powerful resource to study transcriptional regulation during myelopoiesis and to infer the likely functions of unannotated genes in human innate immunity. PMID:25717144

  5. Delineation of Natural Killer Cell Differentiation from Myeloid Progenitors in Human.

    PubMed

    Chen, Qingfeng; Ye, Weijian; Jian Tan, Wei; Mei Yong, Kylie Su; Liu, Min; Qi Tan, Shu; Loh, Eva; Te Chang, Kenneth; Chye Tan, Thiam; Preiser, Peter R; Chen, Jianzhu

    2015-01-01

    Understanding of natural killer (NK) cell development in human is incomplete partly because of limited access to appropriate human tissues. We have developed a cytokine-enhanced humanized mouse model with greatly improved reconstitution and function of human NK cells. Here we report the presence of a cell population in the bone marrow of the cytokine-treated humanized mice that express both NK cell marker CD56 and myeloid markers such as CD36 and CD33. The CD56(+)CD33(+)CD36(+) cells are also found in human cord blood, fetal and adult bone marrow. Although the CD56(+)CD33(+)CD36(+) cells do not express the common NK cell functional receptors and exhibit little cytotoxic and cytokine-producing activities, they readily differentiate into mature NK cells by acquiring expression of NK cell receptors and losing expression of the myeloid markers. Further studies show that CD33(+)CD36(+) myeloid NK precursors are derived from granulo-myelomonocytic progenitors. These results delineate the pathway of human NK cell differentiation from myeloid progenitors in the bone marrow and suggest the utility of humanized mice for studying human hematopoiesis. PMID:26456148

  6. A monoclonal antibody that recognizes B cells and B cell precursors in mice

    SciTech Connect

    Coffman, R.L.; Weissman, I.L.

    1981-02-01

    The monoclonal antibody, RA3-2C2, appears to be specific for cells within the B cell lineage. This antibody does not recognize thymocytes, peripheral T cells, or nonlymphoid hematopoietic cells in the spleen or bone marrow. Nor does it recognize the pluripotent hematopoietic stem cells, the spleen colony-forming unit, All sIg+ B cells and most plasma cells are RA3-2C2+. In addition, approximately 20% of nucleated bone marrow cells are RA3-2C2+ but sIg-. This population contains B cell precursors that can give rise to sIg+ cells within 2 d in vitro.

  7. Molecular pathways: myeloid complicity in cancer.

    PubMed

    Stromnes, Ingunn M; Greenberg, Philip D; Hingorani, Sunil R

    2014-10-15

    Cancer-induced inflammation results in accumulation of myeloid cells. These myeloid cells include progenitors and progeny of monocytes, granulocytes, macrophages, and dendritic cells. It has become increasingly evident that tumor-dependent factors can condition myeloid cells toward an immunosuppressive and protumorigenic phenotype. Thus, myeloid cells are not simply bystanders in malignancy or barometers of disease burden. Reflecting their dynamic and plastic nature, myeloid cells manifest a continuum of cellular differentiation and are intimately involved at all stages of neoplastic progression. They can promote tumorigenesis through both immune-dependent and -independent mechanisms and can dictate response to therapies. A greater understanding of the inherent plasticity and relationships among myeloid subsets is needed to inform therapeutic targeting. New clinical trials are being designed to modulate the activities of myeloid cells in cancer, which may be essential to maximize the efficacy of both conventional cytotoxic and immune-based therapies for solid tumors. Clin Cancer Res; 20(20); 5157-70. ©2014 AACR. PMID:25047706

  8. Generation of axolotl hematopoietic chimeras

    PubMed Central

    Lopez, David; Scott, Edward W.

    2015-01-01

    Wound repair is an extremely complex process that requires precise coordination between various cell types including immune cells. Unfortunately, in mammals this usually results in scar formation instead of restoration of the original fully functional tissue, otherwise known as regeneration. Various animal models like frogs and salamanders are currently being studied to determine the intracellular and intercellular pathways, controlled by gene expression, that elicit cell proliferation, differentiation, and migration of cells during regenerative healing. Now, the necessary genetic tools to map regenerative pathways are becoming available for the axolotl salamander, thus allowing comparative studies between scarring and regeneration. Here, we describe in detail three methods to produce axolotl hematopoietic cell-tagged chimeras for the study of hematopoiesis and regeneration. PMID:26366424

  9. Radioimmunotherapy for hematopoietic cell transplantation.

    PubMed

    Jurcic, Joseph G

    2013-04-01

    Radioimmunotherapy (RIT) represents an attractive strategy to deliver radiation selectively to tumor and other target organs while minimizing toxicity to normal tissues. RIT with β-particle-emitting isotopes targeting CD33, CD45 and CD66 can potentially allow intensification of conditioning before hematopoietic cell transplantation (HCT) in leukemia. Similarly, RIT directed against CD20 has shown promise in the setting of autologous and allogeneic HCT for B-cell lymphomas. α-particle immunotherapy with isotopes such as bismuth-213, actinium-225 and astatinine-211 offers the possibility of more selective and efficient killing of target cells while sparing the surrounding normal cells. Pretargeting strategies may further improve target:normal organ dose ratios. While RIT has demonstrated significant antitumor activity, ultimately, randomized studies will be required to determine if conditioning regimens that include this therapeutic modality can improve patient outcomes after HCT. PMID:23557421

  10. mTOR masters monocytic myeloid-derived suppressor cells in mice with allografts or tumors

    PubMed Central

    Wu, Tingting; Zhao, Yang; Wang, Hao; Li, yang; Shao, Lijuan; Wang, Ruoyu; Lu, Jun; Yang, Zhongzhou; Wang, Junjie; Zhao, Yong

    2016-01-01

    CD11b+ Gr1+ myeloid-derived suppressor cells (MDSCs) play critical roles in controlling the processes of tumors, infections, autoimmunity and graft rejection. Immunosuppressive drug rapamycin (RPM), targeting on the key cellular metabolism molecule mTOR, is currently used in clinics to treat patients with allo-grafts, autoimmune diseases and tumors. However, the effect of RPM on MDSCs has not been studied. RPM significantly decreases the cell number and the immunosuppressive ability on T cells of CD11b+ Ly6Chigh monocytic MDSCs (M-MDSCs) in both allo-grafts-transplanted and tumor-bearing mice respectively. Mice with a myeloid-specific deletion of mTOR have poor M-MDSCs after grafting with allo-skin tissue or a tumor. Grafting of allo-skin or tumors significantly activates glycolysis pathways in myeloid precursor cells in bone marrow, which is inhibited by RPM or mTOR deletion. 2-deoxyglucose (2-DG), an inhibitor of the glycolytic pathway, inhibits M-MDSC differentiation from precursors, while enhancing glycolysis by metformin significantly rescues the RPM-caused deficiency of M-MDSCs. Therefore, we offer evidence supporting that mTOR is an intrinsic factor essential for the differentiation and immunosuppressive function of M-MDSCs and that these metabolism-relevant medicines may impact MDSCs-mediated immunosuppression or immune tolerance induction, which is of considerable clinical importance in treating graft rejection, autoimmune diseases and cancers. PMID:26833095

  11. Polyimide Precursor Solid Residuum

    NASA Technical Reports Server (NTRS)

    Weiser, Erik S. (Inventor); St.Clair, Terry L. (Inventor); Echigo, Yoshiaki (Inventor); Kaneshiro, Hisayasu (Inventor)

    2001-01-01

    A polyimide precursor solid residuum is an admixture of an aromatic dianhydride or derivative thereof and an aromatic diamine or derivative thereof plus a complexing agent, which is complexed with the admixture by hydrogen bonding. The polyimide precursor solid residuum is effectively employed in the preparation of polyimide foam and the fabrication of polyimide foam structures.

  12. The effect of smoking on myeloid-related protein-8 and myeloid-related protein-14.

    PubMed

    Ertugrul, Abdullah Seckin; Sahin, Hacer

    2016-05-20

    The aim of this study was to determine the myeloid-related protein-8 and myeloid-related protein-14 levels in the gingival crevicular fluid of smoker patients with generalized aggressive periodontitis (SAgP), smoker patients with chronic periodontitis (SCP), smoker patients with gingivitis (SG-smoker control), non-smoker patients with generalized aggressive periodontitis (AgP), non-smoker patients with chronic periodontitis (CP), and non-smoker patients with gingivitis (G-non-smoker control). The periodontal statuses of the patients were determined by periodontal clinical measurements and radiographical evaluations. The levels of myeloid-related protein-8 and myeloid-related protein-14 in the gingival crevicular fluid were assessed using enzyme-linked immuno sorbent assay. The myeloid-related protein-8 and myeloid-related protein-14 levels in the gingival crevicular fluid of patients with generalized aggressive periodontitis (non-smoker and smoker) were found to be statistically higher than patients with chronic periodontitis (non-smoker and smoker) and patients with gingivitis (non-smoker and smoker). Myeloid-related protein-8 and myeloid-related protein-14 levels of non-smokers were significantly higher than smokers in all types of periodontitis and gingivitis. The decreased myeloid-related protein-8 and myeloid-related protein-14 level could have prevented the haemostasis of calcium which plays a significant role in the migration of neutrophiles. Smoking affects myeloid-related protein-8 and myeloid-related protein-14 levels and may inhibit the antimicrobial efficiency against microorganisms. Due to these reasons smoker generalized aggressive periodontitis patients need to be treated in detail and their maintenance durations should be shortened. PMID:27223132

  13. Omacetaxine Mepesuccinate for Chronic Myeloid Leukemia.

    PubMed

    Rosshandler, Yasmin; Shen, Ann Q; Cortes, Jorge; Khoury, Hanna Jean

    2016-05-01

    Omacetaxine mepesuccinate is approved by the Food and Drug Administration in the United States for the treatment of chronic myeloid leukemia in chronic or accelerated phase resistant to two or more tyrosine kinase inhibitors. This review summarizes the mode of action, pharmacokinetics, efficacy and safety of omacetaxine mepesuccinate. Omacetaxine mepesuccinate has activity in chronic myeloid leukemia, especially in the chronic phase, regardless of the presence of ABL1 kinase domain mutations. Omacetaxine mepesuccinate has distinct but manageable adverse events profile. Omacetaxine mepesuccinate is a treatment option for a subset of patients with refractory chronic myeloid leukemia. PMID:26853281

  14. Metalloproteinases: A functional pathway for myeloid cells

    PubMed Central

    Chou, Jonathan; Chan, Matilda F.; Werb, Zena

    2015-01-01

    Myeloid cells have diverse roles in regulating immunity, inflammation, and extracellular matrix (ECM) turnover. To accomplish these tasks, myeloid cells carry an arsenal of metalloproteinases, which include the matrix metalloproteinases (MMPs) and the adamalysins. These enzymes have diverse substrate repertoires, and are thus involved in mediating proteolytic cascades, cell migration and cell signaling. Dysregulation of metalloproteinases contributes to pathogenic processes, including inflammation, fibrosis and cancer. Metalloproteinases also have important non-proteolytic functions in controlling cytoskeletal dynamics during macrophage fusion and enhancing transcription to promote anti-viral immunity. This review highlights the diverse contributions of metalloproteinases to myeloid cell functions. PMID:27227311

  15. The Biology of Allogeneic Hematopoietic Cell Resistance

    PubMed Central

    Shizuru, Judith A.; Bhattacharya, Deepta; Cavazzana-Calvo, Marina

    2016-01-01

    At the most basic level, success of an allogeneic hematopoietic cell transplantation (HCT) procedure relies upon the engraftment of recipients with donor hematopoietic stem cells (HSCs) that will generate blood formation for the life of that individual. The formula to achieve durable HSC engraftment involves multiple factors including the recipient conditioning regimen, the nature of the genetic disparity between donor and recipient, and the content of the hematopoietic graft. Animal and clinical studies have shown that the biology of host resistance is complex, involving both immune and nonimmune elements. In this article, we review the factors that contribute to host resistance, describe emerging concepts on the basic biology of resistance, and discuss hematopoietic resistance as it relates specifically to patients with severe combined immunodeficiencies (SCID)— disorders that bring unique insights into the dynamics of cell replacement by allogeneic HSCs and progenitor cells. PMID:19913629

  16. A retrospective cohort study of cause-specific mortality and incidence of hematopoietic malignancies in Chinese benzene-exposed workers.

    PubMed

    Linet, Martha S; Yin, Song-Nian; Gilbert, Ethel S; Dores, Graça M; Hayes, Richard B; Vermeulen, Roel; Tian, Hao-Yuan; Lan, Qing; Portengen, Lutzen; Ji, Bu-Tian; Li, Gui-Lan; Rothman, Nathaniel

    2015-11-01

    Benzene exposure has been causally linked with acute myeloid leukemia (AML), but inconsistently associated with other hematopoietic, lymphoproliferative and related disorders (HLD) or solid tumors in humans. Many neoplasms have been described in experimental animals exposed to benzene. We used Poisson regression to estimate adjusted relative risks (RR) and the likelihood ratio statistic to derive confidence intervals for cause-specific mortality and HLD incidence in 73,789 benzene-exposed compared with 34,504 unexposed workers in a retrospective cohort study in 12 cities in China. Follow-up and outcome assessment was based on factory, medical and other records. Benzene-exposed workers experienced increased risks for all-cause mortality (RR = 1.1, 95% CI = 1.1, 1.2) due to excesses of all neoplasms (RR = 1.3, 95% CI = 1.2, 1.4), respiratory diseases (RR = 1.7, 95% CI = 1.2, 2.3) and diseases of blood forming organs (RR = ∞, 95% CI = 3.4, ∞). Lung cancer mortality was significantly elevated (RR = 1.5, 95% CI = 1.2, 1.9) with similar RRs for males and females, based on three-fold more cases than in our previous follow-up. Significantly elevated incidence of all myeloid disorders reflected excesses of myelodysplastic syndrome/acute myeloid leukemia (RR = 2.7, 95% CI = 1.2, 6.6) and chronic myeloid leukemia (RR = 2.5, 95% CI = 0.8, 11), and increases of all lymphoid disorders included excesses of non-Hodgkin lymphoma (RR = 3.9, 95%CI = 1.5, 13) and all lymphoid leukemia (RR = 5.4, 95%CI = 1.0, 99). The 28-year follow-up of Chinese benzene-exposed workers demonstrated increased risks of a broad range of myeloid and lymphoid neoplasms, lung cancer, and respiratory diseases and suggested possible associations with other malignant and non-malignant disorders. PMID:25944549

  17. Hematopoietic G-protein-coupled receptor kinase 2 deficiency decreases atherosclerotic lesion formation in LDL receptor-knockout mice

    PubMed Central

    Otten, Jeroen J. T.; de Jager, Saskia C. A.; Kavelaars, Annemieke; Seijkens, Tom; Bot, Ilze; Wijnands, Erwin; Beckers, Linda; Westra, Marijke M.; Bot, Martine; Busch, Matthias; Bermudez, Beatriz; van Berkel, Theo J. C.; Heijnen, Cobi J.; Biessen, Erik A. L.

    2013-01-01

    Leukocyte chemotaxis is deemed instrumental in initiation and progression of atherosclerosis. It is mediated by G-protein-coupled receptors (e.g., CCR2 and CCR5), the activity of which is controlled by G-protein-coupled receptor kinases (GRKs). In this study, we analyzed the effect of hematopoietic deficiency of a potent regulator kinase of chemotaxis (GRK2) on atherogenesis. LDL receptor-deficient (LDLr−/−) mice with heterozygous hematopoietic GRK2 deficiency, generated by bone marrow transplantation (n=15), displayed a dramatic attenuation of plaque development, with 79% reduction in necrotic core and increased macrophage content. Circulating monocytes decreased and granulocytes increased in GRK2+/− chimeras, which could be attributed to diminished granulocyte colony-forming units in bone marrow. Collectively, these data pointed to myeloid cells as major mediators of the impaired atherogenic response in GRK2+/− chimeras. LDLr−/− mice with macrophage/granulocyte-specific GRK2 deficiency (LysM-Cre GRK2flox/flox; n=8) failed to mimic the aforementioned phenotype, acquitting these cells as major responsible subsets for GRK2 deficiency-associated atheroprotection. To conclude, even partial hematopoietic GRK2 deficiency prevents atherosclerotic lesion progression beyond the fatty streak stage, identifying hematopoietic GRK2 as a potential target for intervention in atherosclerosis.—Otten, J. J. T., de Jager, S. C. A., Kavelaars, A., Seijkens, T., Bot, I., Wijnands, E., Beckers, L., Westra, M. M., Bot, M., Busch, M., Bermudez, B., van Berkel, T. J. C., Heijnen, C. J., Biessen, E. A. L. Hematopoietic G-protein-coupled receptor kinase 2 deficiency decreases atherosclerotic lesion formation in LDL receptor-knockout mice. PMID:23047899

  18. TGFβ restores hematopoietic homeostasis after myelosuppressive chemotherapy

    PubMed Central

    Brenet, Fabienne; Kermani, Pouneh; Spektor, Roman; Rafii, Shahin

    2013-01-01

    Myelosuppression is a life-threatening complication of antineoplastic therapy, but treatment is restricted to a few cytokines with unilineage hematopoietic activity. Although hematopoietic stem cells (HSCs) are predominantly quiescent during homeostasis, they are rapidly recruited into cell cycle by stresses, including myelosuppressive chemotherapy. Factors that induce HSCs to proliferate during stress have been characterized, but it is not known how HSC quiescence is then reestablished. In this study, we show that TGFβ signaling is transiently activated in hematopoietic stem and progenitor cells (HSPCs) during hematopoietic regeneration. Blockade of TGFβ signaling after chemotherapy accelerates hematopoietic reconstitution and delays the return of cycling HSCs to quiescence. In contrast, TGFβ blockade during homeostasis fails to induce cycling of HSPCs. We identified the cyclin-dependent kinase inhibitor Cdkn1c (p57) as a key downstream mediator of TGFβ during regeneration because the recovery of chimeric mice, incapable of expressing p57 in HSPCs, phenocopies blockade of TGFβ signaling after chemotherapy. This study demonstrates that context-dependent activation of TGFβ signaling is central to an unrecognized counterregulatory mechanism that promotes homeostasis once hematopoiesis has sufficiently recovered from myelosuppressive chemotherapy. These results open the door to new, potentially superior, approaches to promote multilineage hematopoietic recovery by blocking the TGFβ signaling that dampens regeneration. PMID:23440043

  19. SNP Array in Hematopoietic Neoplasms: A Review

    PubMed Central

    Song, Jinming; Shao, Haipeng

    2015-01-01

    Cytogenetic analysis is essential for the diagnosis and prognosis of hematopoietic neoplasms in current clinical practice. Many hematopoietic malignancies are characterized by structural chromosomal abnormalities such as specific translocations, inversions, deletions and/or numerical abnormalities that can be identified by karyotype analysis or fluorescence in situ hybridization (FISH) studies. Single nucleotide polymorphism (SNP) arrays offer high-resolution identification of copy number variants (CNVs) and acquired copy-neutral loss of heterozygosity (LOH)/uniparental disomy (UPD) that are usually not identifiable by conventional cytogenetic analysis and FISH studies. As a result, SNP arrays have been increasingly applied to hematopoietic neoplasms to search for clinically-significant genetic abnormalities. A large numbers of CNVs and UPDs have been identified in a variety of hematopoietic neoplasms. CNVs detected by SNP array in some hematopoietic neoplasms are of prognostic significance. A few specific genes in the affected regions have been implicated in the pathogenesis and may be the targets for specific therapeutic agents in the future. In this review, we summarize the current findings of application of SNP arrays in a variety of hematopoietic malignancies with an emphasis on the clinically significant genetic variants. PMID:27600067

  20. Rapid Inflammation in Mice Lacking Both SOCS1 and SOCS3 in Hematopoietic Cells.

    PubMed

    Ushiki, Takashi; Huntington, Nicholas D; Glaser, Stefan P; Kiu, Hiu; Georgiou, Angela; Zhang, Jian-Guo; Metcalf, Donald; Nicola, Nicos A; Roberts, Andrew W; Alexander, Warren S

    2016-01-01

    The Suppressors of Cytokine Signalling (SOCS) proteins are negative regulators of cytokine signalling required to prevent excess cellular responses. SOCS1 and SOCS3 are essential to prevent inflammatory disease, SOCS1 by attenuating responses to IFNγ and gamma-common (γc) cytokines, and SOCS3 via regulation of G-CSF and IL-6 signalling. SOCS1 and SOCS3 show significant sequence homology and are the only SOCS proteins to possess a KIR domain. The possibility of overlapping or redundant functions was investigated in inflammatory disease via generation of mice lacking both SOCS1 and SOCS3 in hematopoietic cells. Loss of SOCS3 significantly accelerated the pathology and inflammatory disease characteristic of SOCS1 deficiency. We propose a model in which SOCS1 and SOCS3 operate independently to control specific cytokine responses and together modulate the proliferation and activation of lymphoid and myeloid cells to prevent rapid inflammatory disease. PMID:27583437

  1. Allogeneic hematopoietic stem cell transplantation for inherited bone marrow failure syndromes.

    PubMed

    Dalle, Jean-Hugues; Peffault de Latour, Régis

    2016-04-01

    Inherited bone marrow failure (IBMF) syndromes are a heterogeneous group of rare hematological disorders characterized by the impairment of hematopoiesis, which harbor specific clinical presentations and pathogenic mechanisms. Some of these syndromes may progress through clonal evolution, myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Most prominent are failures of DNA repair such as Fanconi Anemia and much rarer failure of ribosomal apparatus, e.g., Diamond Blackfan Anemia or of telomere elongation such as dyskeratosis congenita. In these congenital disorders, hematopoietic stem cell transplantation (HSCT) is often a consideration. However, HSCT will not correct the underlying disease and possible co-existing extra-medullary (multi)-organ defects, but will improve BMF. Indications as well as transplantation characteristics are most of the time controversial in this setting because of the rarity of reported cases. The present paper proposes a short overview of current practices. PMID:26872907

  2. Wnt signaling induces transcription, spatial proximity, and translocation of fusion gene partners in human hematopoietic cells.

    PubMed

    Ugarte, Giorgia D; Vargas, Macarena F; Medina, Matías A; León, Pablo; Necuñir, David; Elorza, Alvaro A; Gutiérrez, Soraya E; Moon, Randall T; Loyola, Alejandra; De Ferrari, Giancarlo V

    2015-10-01

    Chromosomal translocations are frequently associated with a wide variety of cancers, particularly hematologic malignancies. A recurrent chromosomal abnormality in acute myeloid leukemia is the reciprocal translocation t(8;21) that fuses RUNX1 and ETO genes. We report here that Wnt/β-catenin signaling increases the expression of ETO and RUNX1 genes in human hematopoietic progenitors. We found that β-catenin is rapidly recruited into RNA polymerase II transcription factories (RNAPII-Ser5) and that ETO and RUNX1 genes are brought into close spatial proximity upon Wnt3a induction. Notably, long-term treatment of cells with Wnt3a induces the generation a frequent RUNX1-ETO translocation event. Thus, Wnt/β-catenin signaling induces transcription and translocation of RUNX1 and ETO fusion gene partners, opening a novel window to understand the onset/development of leukemia. PMID:26333776

  3. Hematopoietic stem cell dysfunction underlies the progressive lymphocytopenia in XLF/Cernunnos deficiency

    PubMed Central

    Avagyan, Serine; Churchill, Michael; Yamamoto, Kenta; Crowe, Jennifer L.; Li, Chen; Lee, Brian J.; Zheng, Tian; Mukherjee, Siddhartha

    2014-01-01

    XRCC4-like factor (XLF/Cernunnos) is a component of the nonhomologous end-joining (NHEJ) pathway of double-strand DNA break repair. XLF-deficient patients develop a severe progressive lymphocytopenia. Although NHEJ is required for V(D)J recombination and lymphocyte development, XLF-deficient mice have normal V(D)J recombination, highlighting the need for an alternative mechanism for the lymphocytopenia. Here, we report that XLF-deficient mice recapitulate the age-dependent lymphocytopenia of patients. We show that XLF deficiency leads to premature aging of hematopoietic stem cells (HSCs), measured by decreased functional capacity in transplantation assays, preferential myeloid reconstitution, and reduced self-renewal at a young age. We propose that premature aging of HSCs, together with previously reported defects in class-switch recombination and memory immune response, underlies the progressive and severe lymphocytopenia in XLF-deficient patients in the absence of measurable V(D)J recombination defects. PMID:25075129

  4. Hematopoietic stem cell dysfunction underlies the progressive lymphocytopenia in XLF/Cernunnos deficiency.

    PubMed

    Avagyan, Serine; Churchill, Michael; Yamamoto, Kenta; Crowe, Jennifer L; Li, Chen; Lee, Brian J; Zheng, Tian; Mukherjee, Siddhartha; Zha, Shan

    2014-09-01

    XRCC4-like factor (XLF/Cernunnos) is a component of the nonhomologous end-joining (NHEJ) pathway of double-strand DNA break repair. XLF-deficient patients develop a severe progressive lymphocytopenia. Although NHEJ is required for V(D)J recombination and lymphocyte development, XLF-deficient mice have normal V(D)J recombination, highlighting the need for an alternative mechanism for the lymphocytopenia. Here, we report that XLF-deficient mice recapitulate the age-dependent lymphocytopenia of patients. We show that XLF deficiency leads to premature aging of hematopoietic stem cells (HSCs), measured by decreased functional capacity in transplantation assays, preferential myeloid reconstitution, and reduced self-renewal at a young age. We propose that premature aging of HSCs, together with previously reported defects in class-switch recombination and memory immune response, underlies the progressive and severe lymphocytopenia in XLF-deficient patients in the absence of measurable V(D)J recombination defects. PMID:25075129

  5. Hematopoietic stem cell transplantation in immunocompetent hosts without radiation or chemotherapy.

    PubMed

    Chhabra, Akanksha; Ring, Aaron M; Weiskopf, Kipp; Schnorr, Peter John; Gordon, Sydney; Le, Alan C; Kwon, Hye-Sook; Ring, Nan Guo; Volkmer, Jens; Ho, Po Yi; Tseng, Serena; Weissman, Irving L; Shizuru, Judith A

    2016-08-10

    Hematopoietic stem cell (HSC) transplantation can cure diverse diseases of the blood system, including hematologic malignancies, anemias, and autoimmune disorders. However, patients must undergo toxic conditioning regimens that use chemotherapy and/or radiation to eliminate host HSCs and enable donor HSC engraftment. Previous studies have shown that anti-c-Kit monoclonal antibodies deplete HSCs from bone marrow niches, allowing donor HSC engraftment in immunodeficient mice. We show that host HSC clearance is dependent on Fc-mediated antibody effector functions, and enhancing effector activity through blockade of CD47, a myeloid-specific immune checkpoint, extends anti-c-Kit conditioning to fully immunocompetent mice. The combined treatment leads to elimination of >99% of host HSCs and robust multilineage blood reconstitution after HSC transplantation. This targeted conditioning regimen that uses only biologic agents has the potential to transform the practice of HSC transplantation and enable its use in a wider spectrum of patients. PMID:27510901

  6. FoxO3a Directs a Protective Autophagy Program in Hematopoietic Stem Cells

    PubMed Central

    Warr, Matthew R.; Binnewies, Mikhail; Flach, Johanna; Reynaud, Damien; Garg, Trit; Malhotra, Ritu; Debnath, Jayanta; Passegué, Emmanuelle

    2013-01-01

    Blood production is ensured by rare self-renewing hematopoietic stem cells (HSCs). How HSCs accommodate the diverse cellular stresses associated with their life-long activity remains elusive. Here, we identify autophagy as an essential mechanism protecting HSCs from metabolic stress. We show that HSCs, in contrast to their short-lived myeloid progeny, robustly induce autophagy following ex vivo cytokine withdrawal and in vivo caloric restriction. We demonstrate that FoxO3a is critical to maintain a gene expression program that poise HSCs for rapid induction of autophagy upon starvation. Notably, we find that old HSCs retain an intact FoxO3a-driven pro-autophagy gene program, and that ongoing autophagy is needed to mitigate an energy crisis and allow their survival. Our results demonstrate that autophagy is essential for the life-long maintenance of the HSC compartment and for supporting an old, failing blood system. PMID:23389440

  7. FGF signaling restricts hematopoietic stem cell specification via modulation of the BMP pathway

    PubMed Central

    Pouget, Claire; Peterkin, Tessa; Simões, Filipa Costa; Lee, Yoonsung; Traver, David; Patient, Roger

    2015-01-01

    SUMMARY Hematopoietic stem cells (HSCs) are produced during embryogenesis from the floor of the dorsal aorta. The localization of HSCs is dependent upon the presence of instructive signals on the ventral side of the vessel. The nature of the extrinsic molecular signals that control the aortic hematopoietic niche is currently poorly understood. Here we demonstrate a novel requirement for FGF signaling in the specification of aortic hemogenic endothelium. Our results demonstrate that FGF signaling normally acts to repress BMP activity in the subaortic mesenchyme through transcriptional inhibition of bmp4, as well as through activation of two BMP antagonists, noggin2 and gremlin1a. Taken together, these findings demonstrate a key role for FGF signaling in establishment of the developmental HSC niche via its regulation of BMP activity in the subaortic mesenchyme. These results should help inform strategies to recapitulate the development of HSCs in vitro from pluripotent precursors. PMID:25429520

  8. Progressive maturation toward hematopoietic stem cells in the mouse embryo aorta.

    PubMed

    Boisset, Jean-Charles; Clapes, Thomas; Klaus, Anna; Papazian, Natalie; Onderwater, Jos; Mommaas-Kienhuis, Mieke; Cupedo, Tom; Robin, Catherine

    2015-01-15

    Clusters of cells attached to the endothelium of the main embryonic arteries were first observed a century ago. Present in most vertebrate species, such clusters, or intraaortic hematopoietic clusters (IAHCs), derive from specialized hemogenic endothelial cells and contain the first few hematopoietic stem cells (HSCs) generated during embryonic development. However, some discrepancies remained concerning the spatio-temporal appearance and the numbers of IAHCs and HSCs. Therefore, the exact cell composition and function of IAHCs remain unclear to date. We show here that IAHCs contain pre-HSCs (or HSC precursors) that can mature into HSCs in vivo (as shown by the successful long-term multilineage reconstitution of primary neonates and secondary adult recipients). Such IAHC pre-HSCs could contribute to the HSC pool increase observed at midgestation. The novel insights in pre-HSC to HSC transition represent an important step toward generating transplantable HSCs in vitro that are needed for autologous HSC transplantation therapies. PMID:25301706

  9. Replication stress caused by low MCM expression limits fetal erythropoiesis and hematopoietic stem cell functionality

    PubMed Central

    Alvarez, Silvia; Díaz, Marcos; Flach, Johanna; Rodriguez-Acebes, Sara; López-Contreras, Andrés J.; Martínez, Dolores; Cañamero, Marta; Fernández-Capetillo, Oscar; Isern, Joan; Passegué, Emmanuelle; Méndez, Juan

    2015-01-01

    Replicative stress during embryonic development influences ageing and predisposition to disease in adults. A protective mechanism against replicative stress is provided by the licensing of thousands of origins in G1 that are not necessarily activated in the subsequent S-phase. These ‘dormant' origins provide a backup in the presence of stalled forks and may confer flexibility to the replication program in specific cell types during differentiation, a role that has remained unexplored. Here we show, using a mouse strain with hypomorphic expression of the origin licensing factor mini-chromosome maintenance (MCM)3 that limiting origin licensing in vivo affects the functionality of hematopoietic stem cells and the differentiation of rapidly-dividing erythrocyte precursors. Mcm3-deficient erythroblasts display aberrant DNA replication patterns and fail to complete maturation, causing lethal anemia. Our results indicate that hematopoietic progenitors are particularly sensitive to replication stress, and full origin licensing ensures their correct differentiation and functionality. PMID:26456157

  10. Hematopoietic microenvironment. Origin, lineage, and transplantability of the stromal cells in long-term bone marrow cultures from chimeric mice

    SciTech Connect

    Perkins, S.; Fleischman, R.A.

    1988-04-01

    Studies of bone marrow transplant patients have suggested that the stromal cells of the in vitro hematopoietic microenvironment are transplantable into conditioned recipients. Moreover, in patients with myeloproliferative disorders, all of the stromal cells, which include presumptive endothelial cells, appear to be derived from hematopoietic precursors. To confirm these findings, we have constructed two chimeric mouse models: (a) traditional radiation chimeras, and (b) fetal chimeras, produced by placental injection of bone marrow into genetically anemic Wx/Wv fetuses, a technique that essentially precludes engraftment of nonhematopoietic cells. Using two-color indirect immunofluorescence, the stromal cells in long-term bone marrow culture derived from these chimeras were analyzed for donor or host origin by strain-specific H-2 antigens, and for cell lineage by a variety of other specific markers. 75-95% of the stromal cells were shown to be hematopoietic cells of the monocyte-macrophage lineage, based upon donor origin, phagocytosis, and expression of specific hematopoietic surface antigens. The remaining 5-25% of the stromal cells were exclusively host in origin. Apart from occasional fat cells, these cells uniformly expressed collagen type IV, laminin, and a surface antigen associated with endothelial cells. Since these endothelial-like cells are not transplantable into radiation or fetal chimeras, they are not derived from hematopoietic stem cells. The contrast between our findings and human studies suggests either unexpected species differences in the origin of stromal lineages or limitations in the previous methodology used to detect nonhematopoietic stromal cells.

  11. Hematopoietic Acute Radiation Syndrome (Bone marrow syndrome, Aplastic Anemia): Molecular Mechanisms of Radiation Toxicity.

    NASA Astrophysics Data System (ADS)

    Popov, Dmitri

    Key Words: Aplastic Anemia (AA), Pluripotential Stem Cells (PSC) Introduction: Aplastic Anemia (AA) is a disorder of the pluripotential stem cells involve a decrease in the number of cells of myeloid, erythroid and megakaryotic lineage [Segel et al. 2000 ]. The etiology of AA include idiopathic cases and secondary aplastic anemia after exposure to drugs, toxins, chemicals, viral infections, lympho-proliferative diseases, radiation, genetic causes, myelodisplastic syndromes and hypoplastic anemias, thymomas, lymphomas. [Brodskyet al. 2005.,Modan et al. 1975., Szklo et al. 1975]. Hematopoietic Acute Radiation Syndrome (or Bone marrow syndrome, or Radiation-Acquired Aplastic Anemia) is the acute toxic syndrome which usually occurs with a dose of irradiation between 0.7 and 10 Gy (70- 1000 rads), depending on the species irradiated. [Waselenko et al., 2004]. The etiology of bone morrow damage from high-level radiation exposure results depends on the radiosensitivity of certain bone marrow cell lines. [Waselenko et al. 2004] Aplastic anemia after radiation exposure is a clinical syndrome that results from a marked disorder of bone marrow blood cell production. [Waselenko et al. 2004] Radiation hematotoxicity is mediated via genotoxic and other specific toxic mechanisms, leading to aplasia, cell apoptosis or necrosis, initiation via genetic mechanisms of clonal disorders, in cases such as the acute radiation-acquired form of AA. AA results from radiation injury to pluripotential and multipotential stem cells in the bone marrow. The clinical signs displayed in reticulocytopenia, anemia, granulocytopenia, monocytopenia, and thrombocytopenia. The number of marrow CD34+ cells (multipotential hematopoietic progenitors) and their derivative colony-forming unit{granulocyte-macrophage (CFU-GM) and burst forming unit {erythroid (BFU{E) are reduced markedly in patients with AA. [Guinan 2011, Brodski et al. 2005, Beutler et al.,2000] Cells expressing CD34 (CD34+ cell) are normally

  12. Recognizing familial myeloid leukemia in adults

    PubMed Central

    Nickels, Eric M.; Soodalter, Jesse; Churpek, Jane E.

    2013-01-01

    Germline testing for familial cases of myeloid leukemia in adults is becoming more common with the recognition of multiple genetic syndromes predisposing people to bone marrow disease. Currently, Clinical Laboratory Improvement Amendments approved testing exists for several myeloid leukemia predisposition syndromes: familial platelet disorder with propensity to acute myeloid leukemia (FPD/AML), caused by mutations in RUNX1; familial AML with mutated CEBPA; familial myelodysplastic syndrome and acute leukemia with mutated GATA2; and the inherited bone marrow failure syndromes, including dyskeratosis congenita, a disease of abnormal telomere maintenance. With the recognition of additional families with a genetic component to their leukemia, new predisposition alleles will likely be identified. We highlight how to recognize and manage these cases as well as outline the characteristics of the major known syndromes. We look forward to future research increasing our understanding of the scope of inherited myeloid leukemia syndromes. PMID:23926458

  13. Vorinostat in Treating Patients With Acute Myeloid Leukemia

    ClinicalTrials.gov

    2014-04-30

    Adult Acute Erythroid Leukemia (M6); Adult Acute Megakaryoblastic Leukemia (M7); Adult Acute Minimally Differentiated Myeloid Leukemia (M0); Adult Acute Monoblastic Leukemia (M5a); Adult Acute Monocytic Leukemia (M5b); Adult Acute Myeloblastic Leukemia With Maturation (M2); Adult Acute Myeloblastic Leukemia Without Maturation (M1); Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Adult Acute Myelomonocytic Leukemia (M4); Adult Acute Promyelocytic Leukemia (M3); Recurrent Adult Acute Myeloid Leukemia; Refractory Cytopenia With Multilineage Dysplasia; Secondary Acute Myeloid Leukemia; Untreated Adult Acute Myeloid Leukemia

  14. Green tea polyphenol epigallocatechin-O-gallate induces cell death by acid sphingomyelinase activation in chronic myeloid leukemia cells.

    PubMed

    Huang, Yuhui; Kumazoe, Motofumi; Bae, Jaehoon; Yamada, Shuhei; Takai, Mika; Hidaka, Shiori; Yamashita, Shuya; Kim, Yoonhee; Won, Yeongseon; Murata, Motoki; Tsukamoto, Shuntaro; Tachibana, Hirofumi

    2015-09-01

    An epidemiological study showed that green tea consumption is associated with a reduced risk of hematopoietic malignancy. The major green tea polyphenol epigallocatechin‑3-O-gallate (EGCG) is reported to have anticancer effects. Chronic myeloid leukemia (CML) is a major hematopoietic malignancy characterized by expansion of myeloid cells. In the present study, we showed EGCG-induced acid sphingomyelinase (ASM) activation and lipid raft clustering in CML cells. The ASM inhibitor desipramine significantly reduced EGCG-induced cell death. Protein kinase Cδ is a well‑known kinase that plays an important role in ASM activation. We observed EGCG-induced phosphorylation of protein kinase Cδ at Ser664. Importantly, EGCG-induced ASM activation was significantly reduced by pretreatment of CML cells with the soluble guanylate cyclase inhibitor NS2028, suggesting that EGCG induced ASM activation through the cyclic guanosine monophosphate (cGMP)-dependent pathway. Indeed, pharmacological inhibition of a cGMP-negative regulator enhanced the anti-CML effect of EGCG. These results indicate that EGCG-induced cell death via the cGMP/ASM pathway in CML cells. PMID:26135316

  15. Green tea polyphenol epigallocatechin-O-gallate induces cell death by acid sphingomyelinase activation in chronic myeloid leukemia cells

    PubMed Central

    HUANG, YUHUI; KUMAZOE, MOTOFUMI; BAE, JAEHOON; YAMADA, SHUHEI; TAKAI, MIKA; HIDAKA, SHIORI; YAMASHITA, SHUYA; KIM, YOONHEE; WON, YEONGSEON; MURATA, MOTOKI; TSUKAMOTO, SHUNTARO; TACHIBANA, HIROFUMI

    2015-01-01

    An epidemiological study showed that green tea consumption is associated with a reduced risk of hematopoietic malignancy. The major green tea polyphenol epigallocatechin-3-O-gallate (EGCG) is reported to have anticancer effects. Chronic myeloid leukemia (CML) is a major hematopoietic malignancy characterized by expansion of myeloid cells. In the present study, we showed EGCG-induced acid sphingomyelinase (ASM) activation and lipid raft clustering in CML cells. The ASM inhibitor desipramine significantly reduced EGCG-induced cell death. Protein kinase Cδ is a well-known kinase that plays an important role in ASM activation. We observed EGCG-induced phos-phorylation of protein kinase Cδ at Ser664. Importantly, EGCG-induced ASM activation was significantly reduced by pretreatment of CML cells with the soluble guanylate cyclase inhibitor NS2028, suggesting that EGCG induced ASM activation through the cyclic guanosine monophosphate (cGMP)-dependent pathway. Indeed, pharmacological inhibition of a cGMP-negative regulator enhanced the anti-CML effect of EGCG. These results indicate that EGCG-induced cell death via the cGMP/ASM pathway in CML cells. PMID:26135316

  16. Differentiation of hematopoietic stem cells in irradiated mouse thymic lobes. Kinetics and phenotype of progeny

    SciTech Connect

    Spangrude, G.J.; Scollay, R. )

    1990-12-01

    To define cell populations which participate in the very early stages of T cell development in the mouse thymus, we enriched hematopoietic stem cells from mouse bone marrow and injected them into thymic lobes of irradiated Ly-5 congenic recipients. The progeny of the stem cells were identified and their phenotypes were determined by two-color flow cytometry for the expression of various cell surface differentiation Ag during the course of their subsequent intrathymic development. The majority of the differentiation which occurred in the first 10 days after intrathymic cell transfer was myeloid in nature; hence, this study demonstrates that the irradiated thymus is not strictly selective for T cell development. Further, the maximum rate of T cell development was observed after intrathymic injection of 200 stem cells. Donor-derived cells which did not express Ag characteristic of the myeloid lineage could be detected and their phenotypes could be determined by flow cytometry as early as 7 days after intrathymic injection. At this time, the cells were still very similar phenotypically to the bone marrow hematopoietic stem cells. Exceptions to this were the expression of stem cell Ag 2 and a decrease in the level of MHC class I Ag expression. After 9 days, the donor-derived cells expressed high levels of the Thy-1 Ag and proceeded to change in cell surface phenotype as differentiation continued. These cell phenotypes are described for the time frame ending 18 days after injection, when most donor-derived cells were phenotypically small CD4+ CD8+ (double-positive) thymocytes.

  17. Hematopoietic Stem Cell Activity Is Regulated by Pten Phosphorylation Through a Niche-Dependent Mechanism.

    PubMed

    Li, Jing; Zhang, Jun; Tang, Minghui; Xin, Junping; Xu, Yan; Volk, Andrew; Hao, Caiqin; Hu, Chenglong; Sun, Jiewen; Wei, Wei; Cao, Quichan; Breslin, Peter; Zhang, Jiwang

    2016-08-01

    The phosphorylated form of Pten (p-Pten) is highly expressed in >70% of acute myeloid leukemia samples. However, the role of p-Pten in normal and abnormal hematopoiesis has not been studied. We found that Pten protein levels are comparable among long-term (LT) hematopoietic stem cells (HSCs), short-term (ST) HSCs, and multipotent progenitors (MPPs); however, the levels of p-Pten are elevated during the HSC-to-MPP transition. To study whether p-Pten is involved in regulating self-renewal and differentiation in HSCs, we compared the effects of overexpression of p-Pten and nonphosphorylated Pten (non-p-Pten) on the hematopoietic reconstitutive capacity (HRC) of HSCs. We found that overexpression of non-p-Pten enhances the LT-HRC of HSCs, whereas overexpression of p-Pten promotes myeloid differentiation and compromises the LT-HRC of HSCs. Such phosphorylation-regulated Pten functioning is mediated by repressing the cell:cell contact-induced activation of Fak/p38 signaling independent of Pten's lipid phosphatase activity because both p-Pten and non-p-Pten have comparable activity in repressing PI3K/Akt signaling. Our studies suggest that, in addition to repressing PI3K/Akt/mTor signaling, non-p-Pten maintains HSCs in bone marrow niches via a cell-contact inhibitory mechanism by inhibiting Fak/p38 signaling-mediated proliferation and differentiation. In contrast, p-Pten promotes the proliferation and differentiation of HSCs by enhancing the cell contact-dependent activation of Src/Fak/p38 signaling. Stem Cells 2016;34:2130-2144. PMID:27096933

  18. Immunotherapy with myeloid cells for tolerance induction

    PubMed Central

    Rodriguez-García, Mercedes; Boros, Peter; Bromberg, Jonathan S.; Ochando, Jordi C.

    2013-01-01

    Purpose of review Understanding the interplay between myeloid dendritic cells and T cells under tolerogenic conditions, and whether their interactions induce the development of antigen-specific regulatory T cells (Tregs) is critical to uncover the mechanisms involved in the induction of indefinite allograft survival. Recent findings Myeloid dendritic cell–T-cell interactions are seminal events that determine the outcome of the immune response, and multiple in-vitro protocols suggest the generation of tolerogenic myeloid dendritic cells that modulate T-cell responses, and determine the outcome of the immune response to an allograft following adoptive transfer. We believe that identifying specific conditions that lead to the generation of tolerogenic myeloid dendritic cells and Tregs are critical for the manipulation the immune response towards the development of transplantation tolerance. Summary We summarize recent findings regarding specific culture conditions that generate tolerogenic myeloid dendritic cells that induce T-cell hyporesponsiveness and Treg development, and represents a novel immunotherapeutic approach to promote the induction of indefinite graft survival prolongation. The interpretations presented here illustrate that different mechanisms govern the generation tolerogenic myeloid dendritic cells, and we discuss the concomitant therapeutic implications. PMID:20616727

  19. Cutaneous myeloid sarcoma of the penile foreskin.

    PubMed

    Afrose, Ruquiya; Nebhnani, Deepa; Wadhwa, Neelam

    2015-01-01

    Myeloid sarcoma, considered to herald the onset of a blast crisis in the setting of chronic myeloproliferative neoplasm/dysplasia, typically presents during the course of the disorder. Cutaneous involvement is uncommon and lesions on genital skin are seldom seen. We present a case of a well-differentiated myeloid sarcoma in the penile foreskin in an apparently healthy 29-year-old male presenting with phimosis. The unusual composition of the inflammatory cell infiltrate, and characteristic sparing of dermal blood vessels, nerves and smooth muscle fibres led to the correct diagnosis. Absence of commonly observed changes in the circumcision skin like those of balanitis xerotica was also helpful. Detailed hematological work up revealed a previously undiagnosed chronic myeloid leukemia in chronic phase. The patient also had simultaneous priapism, another rare presentation of chronic myeloid leukemia. One year hence, the patient is in hematological remission with no evidence of extramedullary disease. Although priapism has been described as a rare presenting symptom in chronic myeloid leukemia, the present case is unique as this is the first time a cutaneous myeloid sarcoma has been documented in the penile foreskin. PMID:24913300

  20. RIPK3 Restricts Myeloid Leukemogenesis by Promoting Cell Death and Differentiation of Leukemia Initiating Cells.

    PubMed

    Höckendorf, Ulrike; Yabal, Monica; Herold, Tobias; Munkhbaatar, Enkhtsetseg; Rott, Stephanie; Jilg, Stefanie; Kauschinger, Johanna; Magnani, Giovanni; Reisinger, Florian; Heuser, Michael; Kreipe, Hans; Sotlar, Karl; Engleitner, Thomas; Rad, Roland; Weichert, Wilko; Peschel, Christian; Ruland, Jürgen; Heikenwalder, Mathias; Spiekermann, Karsten; Slotta-Huspenina, Julia; Groß, Olaf; Jost, Philipp J

    2016-07-11

    Since acute myeloid leukemia (AML) is characterized by the blockade of hematopoietic differentiation and cell death, we interrogated RIPK3 signaling in AML development. Genetic loss of Ripk3 converted murine FLT3-ITD-driven myeloproliferation into an overt AML by enhancing the accumulation of leukemia-initiating cells (LIC). Failed inflammasome activation and cell death mediated by tumor necrosis factor receptor caused this accumulation of LIC exemplified by accelerated leukemia onset in Il1r1(-/-), Pycard(-/-), and Tnfr1/2(-/-) mice. RIPK3 signaling was partly mediated by mixed lineage kinase domain-like. This link between suppression of RIPK3, failed interleukin-1β release, and blocked cell death was supported by significantly reduced RIPK3 in primary AML patient cohorts. Our data identify RIPK3 and the inflammasome as key tumor suppressors in AML. PMID:27411587

  1. Selinexor and Chemotherapy in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia

    ClinicalTrials.gov

    2015-12-15

    Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Recurrent Adult Acute Myeloid Leukemia; Secondary Acute Myeloid Leukemia

  2. Earthquakes: hydrogeochemical precursors

    USGS Publications Warehouse

    Ingebritsen, Steven E.; Manga, Michael

    2014-01-01

    Earthquake prediction is a long-sought goal. Changes in groundwater chemistry before earthquakes in Iceland highlight a potential hydrogeochemical precursor, but such signals must be evaluated in the context of long-term, multiparametric data sets.

  3. Oblimersen, Cytarabine, and Daunorubicin in Treating Older Patients With Acute Myeloid Leukemia

    ClinicalTrials.gov

    2015-12-03

    Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Secondary Acute Myeloid Leukemia; Untreated Adult Acute Myeloid Leukemia

  4. Decitabine, Cytarabine, and Daunorubicin Hydrochloride in Treating Patients With Acute Myeloid Leukemia

    ClinicalTrials.gov

    2016-07-20

    Adult Acute Basophilic Leukemia; Adult Acute Eosinophilic Leukemia; Adult Acute Monoblastic Leukemia; Adult Acute Monocytic Leukemia; Adult Acute Myeloid Leukemia With Maturation; Adult Acute Myeloid Leukemia With t(9;11)(p22;q23); MLLT3-MLL; Adult Acute Myeloid Leukemia Without Maturation; Adult Acute Myelomonocytic Leukemia; Alkylating Agent-Related Acute Myeloid Leukemia; Secondary Acute Myeloid Leukemia; Untreated Adult Acute Myeloid Leukemia

  5. A focused review of hematopoietic neoplasms occurring in the therapy-related setting

    PubMed Central

    Zhang, Liping; Wang, Sa A

    2014-01-01

    Hematological neoplasms developed in patients with a history of cytotoxic therapies comprise a group of diseases with a poor clinical outcome, and collectively categorized as “therapy-related myeloid neoplasms” (t-MN) in the 2008 World Health Organization (WHO) Classification. In recent years, numerous publications have emerged, and these studies have greatly expanded the scope of our understanding in this field. We here focused our review on several selected areas including secondary malignancies occurring in patients with autoimmune diseases; radiation therapy alone as a causative agent; the similarity and differences between therapy-related myelodysplastic syndromes (t-MDS) and acute myeloid leukemia (t-AML); clinical behavior and treatment outcome of t-AML patients with favorable cytogenetics; the incidence and clinical features of myelodysplastic/myeloproliferative neoplasms, as well as acute lymphoblastic leukemia and myeloproliferative neoplasms in patients with prior cytotoxic exposure. These recent studies have shown that therapy-related hematopoietic neoplasms are heterogeneous, and may manifest in various forms, more complex than we have recognized previously. Cytogenetic abnormalities and underlying mutations are likely to be the major factors dictating prognosis. PMID:25120730

  6. DNMT3A and TET2 in the Pre-Leukemic Phase of Hematopoietic Disorders

    PubMed Central

    Sato, Hanae; Wheat, Justin C.; Steidl, Ulrich; Ito, Keisuke

    2016-01-01

    In recent years, advances in next-generation sequencing (NGS) technology have provided the opportunity to detect putative genetic drivers of disease, particularly cancers, with very high sensitivity. This knowledge has substantially improved our understanding of tumor pathogenesis. In hematological malignancies such as acute myeloid leukemia and myelodysplastic syndromes, pioneering work combining multi-parameter flow cytometry and targeted resequencing in leukemia have clearly shown that different classes of mutations appear to be acquired in particular sequences along the hematopoietic differentiation hierarchy. Moreover, as these mutations can be found in “normal” cells recovered during remission and can be detected at relapse, there is strong evidence for the existence of “pre-leukemic” stem cells (pre-LSC). These cells, while phenotypically normal by flow cytometry, morphology, and functional studies, are speculated to be molecularly poised to transform owing to a limited number of predisposing mutations. Identifying these “pre-leukemic” mutations and how they propagate a pre-malignant state has important implications for understanding the etiology of these disorders and for the development of novel therapeutics. NGS studies have found a substantial enrichment for mutations in epigenetic/chromatin remodeling regulators in pre-LSC, and elegant genetic models have confirmed that these mutations can predispose to a variety of hematological malignancies. In this review, we will discuss the current understanding of pre-leukemic biology in myeloid malignancies, and how mutations in two key epigenetic regulators, DNMT3A and TET2, may contribute to disease pathogenesis. PMID:27597933

  7. Reprogramming committed murine blood cells to induced hematopoietic stem cells with defined factors

    PubMed Central

    Riddell, Jonah; Gazit, Roi; Garrison, Brian S.; Guo, Guoji; Saadatpour, Assieh; Mandal, Pankaj K.; Ebina, Wataru; Volchkov, Pavel; Yuan, Guo-Cheng; Orkin, Stuart H.; Rossi, Derrick J.

    2014-01-01

    Hematopoietic stem cells (HSCs) sustain blood formation throughout life and are the functional units of bone marrow transplantation. We show that transient expression of six transcription factors RUNX1T1, HLF, LMO2, PRDM5, PBX1, and ZFP37 imparts multi-lineage transplantation potential onto otherwise committed lymphoid and myeloid progenitors, and myeloid effector cells. Inclusion of MYC-N and MEIS1, and use of polycistronic viruses increase reprogramming efficacy. The reprogrammed cells, designated induced-HSCs (iHSCs), possess clonal multi-lineage differentiation potential, reconstitute stem/progenitor compartments, and are serially transplantable. Single-cell analysis revealed that iHSCs derived under optimal conditions exhibit a gene expression profile that is highly similar to endogenous HSCs. These findings demonstrate that expression of a set of defined factors is sufficient to activate the gene networks governing HSC functional identity in committed blood cells. Our results raise the prospect that blood cell reprogramming may be a strategy for derivation of transplantable stem cells for clinical application. PMID:24766805

  8. Leukemia-related chromosomal loss detected in hematopoietic progenitor cells of benzene-exposed workers

    PubMed Central

    Zhang, Luoping; Lan, Qing; Ji, Zhiying; Li, Guilan; Shen, Min; Vermeulen, Roel; Guo, Weihong; Hubbard, Alan E.; McHale, Cliona M.; Rappaport, Stephen M.; Hayes, Richard B.; Linet, Martha S.; Yin, Songnian; Smith, Martyn T.; Rothman, Nathaniel

    2012-01-01

    Benzene exposure causes acute myeloid leukemia, and hematotoxicity, shown as suppression of mature blood and myeloid progenitor cell numbers. As the leukemia-related aneuploidies monosomy 7 and trisomy 8 previously had been detected in the mature peripheral blood cells of exposed workers, we hypothesized that benzene could cause leukemia through the induction of these aneuploidies in hematopoietic stem and progenitor cells. We measured loss and gain of chromosomes 7 and 8 by fluorescence in situ hybridization in interphase colony-forming unit-granulocyte-macrophage (CFU-GM) cells cultured from otherwise healthy benzene-exposed (n=28) and unexposed (n=14) workers. CFU-GM monosomy 7 and 8 levels (but not trisomy) were significantly increased in subjects exposed to benzene overall, compared to levels in the control subjects (p=0.0055 and p=0.0034, respectively). Levels of monosomy 7 and 8 were significantly increased in subjects exposed to <10 ppm (20%, p=0.0419 and 28%, p=0.0056, respectively) and ≥10 ppm (48%, p=0.0045 and 32%, p=0.0354) benzene, compared with controls, and significant exposure-response trends were detected (ptrend=0.0033 and 0.0057). These data show that monosomies 7 and 8 are produced in a dose-dependent fashion in the blood progenitor cells of workers exposed to benzene and may be mechanistically relevant biomarkers of early effect for benzene and other leukemogens. PMID:22643707

  9. Hematopoietic cell kinase (HCK) as a therapeutic target in immune and cancer cells

    PubMed Central

    Poh, Ashleigh R.; O'Donoghue, Robert J.J.; Ernst, Matthias

    2015-01-01

    The hematopoietic cell kinase (HCK) is a member of the SRC family of cytoplasmic tyrosine kinases (SFKs), and is expressed in cells of the myeloid and B-lymphocyte cell lineages. Excessive HCK activation is associated with several types of leukemia and enhances cell proliferation and survival by physical association with oncogenic fusion proteins, and with functional interactions with receptor tyrosine kinases. Elevated HCK activity is also observed in many solid malignancies, including breast and colon cancer, and correlates with decreased patient survival rates. HCK enhances the secretion of growth factors and pro-inflammatory cytokines from myeloid cells, and promotes macrophage polarization towards a wound healing and tumor-promoting alternatively activated phenotype. Within tumor associated macrophages, HCK stimulates the formation of podosomes that facilitate extracellular matrix degradation, which enhance immune and epithelial cell invasion. By virtue of functional cooperation between HCK and bona fide oncogenic tyrosine kinases, excessive HCK activation can also reduce drug efficacy and contribute to chemo-resistance, while genetic ablation of HCK results in minimal physiological consequences in healthy mice. Given its known crystal structure, HCK therefore provides an attractive therapeutic target to both, directly inhibit the growth of cancer cells, and indirectly curb the source of tumor-promoting changes in the tumor microenvironment. PMID:26087188

  10. DNMT3A and TET2 in the Pre-Leukemic Phase of Hematopoietic Disorders.

    PubMed

    Sato, Hanae; Wheat, Justin C; Steidl, Ulrich; Ito, Keisuke

    2016-01-01

    In recent years, advances in next-generation sequencing (NGS) technology have provided the opportunity to detect putative genetic drivers of disease, particularly cancers, with very high sensitivity. This knowledge has substantially improved our understanding of tumor pathogenesis. In hematological malignancies such as acute myeloid leukemia and myelodysplastic syndromes, pioneering work combining multi-parameter flow cytometry and targeted resequencing in leukemia have clearly shown that different classes of mutations appear to be acquired in particular sequences along the hematopoietic differentiation hierarchy. Moreover, as these mutations can be found in "normal" cells recovered during remission and can be detected at relapse, there is strong evidence for the existence of "pre-leukemic" stem cells (pre-LSC). These cells, while phenotypically normal by flow cytometry, morphology, and functional studies, are speculated to be molecularly poised to transform owing to a limited number of predisposing mutations. Identifying these "pre-leukemic" mutations and how they propagate a pre-malignant state has important implications for understanding the etiology of these disorders and for the development of novel therapeutics. NGS studies have found a substantial enrichment for mutations in epigenetic/chromatin remodeling regulators in pre-LSC, and elegant genetic models have confirmed that these mutations can predispose to a variety of hematological malignancies. In this review, we will discuss the current understanding of pre-leukemic biology in myeloid malignancies, and how mutations in two key epigenetic regulators, DNMT3A and TET2, may contribute to disease pathogenesis. PMID:27597933

  11. Comparative Analysis of the Hematopoietic Progenitor Cells from Placenta, Cord Blood, and Fetal Liver, Based on Their Immunophenotype

    PubMed Central

    Kuchma, Maria D.; Kyryk, Vitaliy M.; Svitina, Hanna M.; Shablii, Yulia M.; Lukash, Lubov L.; Lobyntseva, Galina S.; Shablii, Volodymyr A.

    2015-01-01

    We have investigated the characteristics of human hematopoietic progenitor cells (HPCs) with the CD34+CD45lowSSClow phenotype from full-term placental tissue (FTPT) as compared to cord blood (CB) and fetal liver (FL) cells. We demonstrated the presence of cell subpopulations at various stages of the differentiation with such immunophenotypes as CD34+/lowCD45low/−, CD34++CD45low/−, CD34+++CD45low/−, CD34+/lowCD45hi, and CD34++CD45hi in both first trimester placental tissue (FiTPT) and FTPT which implies their higher phenotypic heterogeneity compared to CB. HPCs of the FTPT origin expressed the CD90 antigen at a higher level compared to its expression by the CB HPCs and the CD133 antigen expression being at the same level in both cases. The HPCs compartment of FTPT versus CB contained higher number of myeloid and erythroid committed cells but lower number of myeloid and lymphoid ones compared to FL HPCs. HPCs of the FTPT and CB origin possess similar potentials for the multilineage differentiation in vitro and similar ratios of myeloid and erythroid progenitors among the committed cells. This observation suggests that the active hematopoiesis occurs in the FTPT. We obtained viable HPCs from cryopreserved placental tissue fragments allowing us to develop procedures for banking and testing of placenta-derived HPCs for clinical use. PMID:26347038

  12. Lineage-specific STAT5 target gene activation in hematopoietic progenitor cells predicts the FLT3(+)-mediated leukemic phenotype.

    PubMed

    Müller, T A; Grundler, R; Istvanffy, R; Rudelius, M; Hennighausen, L; Illert, A L; Duyster, J

    2016-08-01

    Mutations that activate FMS-like tyrosine kinase 3 (FLT3) are frequent occurrences in acute myeloid leukemia. Two distinct types of mutations have been described: internal duplication of the juxtamembranous domain (ITD) and point mutations of the tyrosine kinase domain (TKD). Although both mutations lead to constitutive FLT3 signaling, only FLT3-ITD strongly activates signal transducer and activator of transcription 5 (STAT5). In a murine transplantation model, FLT3-ITD induces a myeloproliferative neoplasm, whereas FLT3-TKD leads to a lymphoid malignancy with significantly longer latency. Here we report that the presence of STAT5 is critical for the development of a myeloproliferative disease by FLT3-ITD in mice. Deletion of Stat5 in FLT3-ITD-induced leukemogenesis leads not only to a significantly longer survival (82 vs 27 days) of the diseased mice, but also to an immunophenotype switch with expansion of the lymphoid cell compartment. Interestingly, we were able to show differential STAT5 activation in FLT3-ITD(+) myeloid and lymphoid murine progenitors. STAT5 target genes such as Oncostatin M were highly expressed in FLT3-ITD(+) myeloid but not in FLT3-ITD(+) lymphoid progenitor cells. Strikingly, FLT3-TKD expression in combination with Oncostatin M is sufficient to reverse the phenotype to a myeloproliferative disease in FLT3-TKD mice. Thus, lineage-specific STAT5 activation in hematopoietic progenitor cells predicts the FLT3(+)-mediated leukemic phenotype in mice. PMID:27046463

  13. Angiogenin Promotes Hematopoietic Regeneration by Dichotomously Regulating Quiescence of Stem and Progenitor Cells.

    PubMed

    Goncalves, Kevin A; Silberstein, Lev; Li, Shuping; Severe, Nicolas; Hu, Miaofen G; Yang, Hailing; Scadden, David T; Hu, Guo-Fu

    2016-08-11

    Regulation of stem and progenitor cell populations is critical in the development, maintenance, and regeneration of tissues. Here, we define a novel mechanism by which a niche-secreted RNase, angiogenin (ANG), distinctively alters the functional characteristics of primitive hematopoietic stem/progenitor cells (HSPCs) compared with lineage-committed myeloid-restricted progenitor (MyePro) cells. Specifically, ANG reduces the proliferative capacity of HSPC while simultaneously increasing proliferation of MyePro cells. Mechanistically, ANG induces cell-type-specific RNA-processing events: tRNA-derived stress-induced small RNA (tiRNA) generation in HSPCs and rRNA induction in MyePro cells, leading to respective reduction and increase in protein synthesis. Recombinant ANG protein improves survival of irradiated animals and enhances hematopoietic regeneration of mouse and human HSPCs in transplantation. Thus, ANG plays a non-cell-autonomous role in regulation of hematopoiesis by simultaneously preserving HSPC stemness and promoting MyePro proliferation. These cell-type-specific functions of ANG suggest considerable therapeutic potential. PMID:27518564

  14. Redefining endothelial progenitor cells via clonal analysis and hematopoietic stem/progenitor cell principals

    PubMed Central

    Mead, Laura E.; Prater, Daniel; Krier, Theresa R.; Mroueh, Karim N.; Li, Fang; Krasich, Rachel; Temm, Constance J.; Prchal, Josef T.

    2007-01-01

    The limited vessel-forming capacity of infused endothelial progenitor cells (EPCs) into patients with cardiovascular dysfunction may be related to a misunderstanding of the biologic potential of the cells. EPCs are generally identified by cell surface antigen expression or counting in a commercially available kit that identifies “endothelial cell colony-forming units” (CFU-ECs). However, the origin, proliferative potential, and differentiation capacity of CFU-ECs is controversial. In contrast, other EPCs with blood vessel-forming ability, termed endothelial colony-forming cells (ECFCs), have been isolated from human peripheral blood. We compared the function of CFU-ECs and ECFCs and determined that CFU-ECs are derived from the hematopoietic system using progenitor assays, and analysis of donor cells from polycythemia vera patients harboring a Janus kinase 2 V617F mutation in hematopoietic stem cell clones. Further, CFU-ECs possess myeloid progenitor cell activity, differentiate into phagocytic macrophages, and fail to form perfused vessels in vivo. In contrast, ECFCs are clonally distinct from CFU-ECs, display robust proliferative potential, and form perfused vessels in vivo. Thus, these studies establish that CFU-ECs are not EPCs and the role of these cells in angiogenesis must be re-examined prior to further clinical trials, whereas ECFCs may serve as a potential therapy for vascular regeneration. PMID:17053059

  15. Pediatric donor cell leukemia after allogeneic hematopoietic stem cell transplantation in AML patient from related donor.

    PubMed

    Bobadilla-Morales, Lucina; Pimentel-Gutiérrez, Helia J; Gallegos-Castorena, Sergio; Paniagua-Padilla, Jenny A; Ortega-de-la-Torre, Citlalli; Sánchez-Zubieta, Fernando; Silva-Cruz, Rocio; Corona-Rivera, Jorge R; Zepeda-Moreno, Abraham; González-Ramella, Oscar; Corona-Rivera, Alfredo

    2015-01-01

    Here we present a male patient with acute myeloid leukemia (AML) initially diagnosed as M5 and with karyotype 46,XY. After induction therapy, he underwent a HLA-matched allogeneic hematopoietic stem cell transplantation, and six years later he relapsed as AML M1 with an abnormal karyotype //47,XX,+10[2]/47,XX,+11[3]/48,XX,+10,+11[2]/46,XX[13]. Based on this, we tested the possibility of donor cell origin by FISH and molecular STR analysis. We found no evidence of Y chromosome presence by FISH and STR analysis consistent with the success of the allogeneic hematopoietic stem cell transplantation from the female donor. FISH studies confirmed trisomies and no evidence of MLL translocation either p53 or ATM deletion. Additionally 28 fusion common leukemia transcripts were evaluated by multiplex reverse transcriptase-polymerase chain reaction assay and were not rearranged. STR analysis showed a complete donor chimerism. Thus, donor cell leukemia (DCL) was concluded, being essential the use of cytological and molecular approaches. Pediatric DCL is uncommon, our patient seems to be the sixth case and additionally it presented a late donor cell leukemia appearance. Different extrinsic and intrinsic mechanisms have been considered to explain this uncommon finding as well as the implications to the patient. PMID:25674158

  16. Transcriptional, epigenetic and retroviral signatures identify regulatory regions involved in hematopoietic lineage commitment.

    PubMed

    Romano, Oriana; Peano, Clelia; Tagliazucchi, Guidantonio Malagoli; Petiti, Luca; Poletti, Valentina; Cocchiarella, Fabienne; Rizzi, Ermanno; Severgnini, Marco; Cavazza, Alessia; Rossi, Claudia; Pagliaro, Pasqualepaolo; Ambrosi, Alessandro; Ferrari, Giuliana; Bicciato, Silvio; De Bellis, Gianluca; Mavilio, Fulvio; Miccio, Annarita

    2016-01-01

    Genome-wide approaches allow investigating the molecular circuitry wiring the genetic and epigenetic programs of human somatic stem cells. Hematopoietic stem/progenitor cells (HSPC) give rise to the different blood cell types; however, the molecular basis of human hematopoietic lineage commitment is poorly characterized. Here, we define the transcriptional and epigenetic profile of human HSPC and early myeloid and erythroid progenitors by a combination of Cap Analysis of Gene Expression (CAGE), ChIP-seq and Moloney leukemia virus (MLV) integration site mapping. Most promoters and transcripts were shared by HSPC and committed progenitors, while enhancers and super-enhancers consistently changed upon differentiation, indicating that lineage commitment is essentially regulated by enhancer elements. A significant fraction of CAGE promoters differentially expressed upon commitment were novel, harbored a chromatin enhancer signature, and may identify promoters and transcribed enhancers driving cell commitment. MLV-targeted genomic regions co-mapped with cell-specific active enhancers and super-enhancers. Expression analyses, together with an enhancer functional assay, indicate that MLV integration can be used to identify bona fide developmentally regulated enhancers. Overall, this study provides an overview of transcriptional and epigenetic changes associated to HSPC lineage commitment, and a novel signature for regulatory elements involved in cell identity. PMID:27095295

  17. Redefining endothelial progenitor cells via clonal analysis and hematopoietic stem/progenitor cell principals.

    PubMed

    Yoder, Mervin C; Mead, Laura E; Prater, Daniel; Krier, Theresa R; Mroueh, Karim N; Li, Fang; Krasich, Rachel; Temm, Constance J; Prchal, Josef T; Ingram, David A

    2007-03-01

    The limited vessel-forming capacity of infused endothelial progenitor cells (EPCs) into patients with cardiovascular dysfunction may be related to a misunderstanding of the biologic potential of the cells. EPCs are generally identified by cell surface antigen expression or counting in a commercially available kit that identifies "endothelial cell colony-forming units" (CFU-ECs). However, the origin, proliferative potential, and differentiation capacity of CFU-ECs is controversial. In contrast, other EPCs with blood vessel-forming ability, termed endothelial colony-forming cells (ECFCs), have been isolated from human peripheral blood. We compared the function of CFU-ECs and ECFCs and determined that CFU-ECs are derived from the hematopoietic system using progenitor assays, and analysis of donor cells from polycythemia vera patients harboring a Janus kinase 2 V617F mutation in hematopoietic stem cell clones. Further, CFU-ECs possess myeloid progenitor cell activity, differentiate into phagocytic macrophages, and fail to form perfused vessels in vivo. In contrast, ECFCs are clonally distinct from CFU-ECs, display robust proliferative potential, and form perfused vessels in vivo. Thus, these studies establish that CFU-ECs are not EPCs and the role of these cells in angiogenesis must be re-examined prior to further clinical trials, whereas ECFCs may serve as a potential therapy for vascular regeneration. PMID:17053059

  18. Absence of WASp Enhances Hematopoietic and Megakaryocytic Differentiation in a Human Embryonic Stem Cell Model.

    PubMed

    Toscano, Miguel G; Muñoz, Pilar; Sánchez-Gilabert, Almudena; Cobo, Marién; Benabdellah, Karim; Anderson, Per; Ramos-Mejía, Verónica; Real, Pedro J; Neth, Olaf; Molinos-Quintana, Agueda; Gregory, Philip D; Holmes, Michael C; Martin, Francisco

    2016-02-01

    The Wiskott-Aldrich syndrome (WAS) is an X-linked primary immunodeficiency caused by mutations in the WAS gene and characterized by severe thrombocytopenia. Although the role of WASp in terminally differentiated lymphocytes and myeloid cells is well characterized, its role in early hematopoietic differentiation and in platelets (Plts) biology is poorly understood. In the present manuscript, we have used zinc finger nucleases targeted to the WAS locus for the development of two isogenic WAS knockout (WASKO) human embryonic stem cell lines (hESCs). Upon hematopoietic differentiation, hESCs-WASKO generated increased ratios of CD34(+)CD45(+) progenitors with altered responses to stem cell factor compared to hESCs-WT. When differentiated toward the megakaryocytic linage, hESCs-WASKO produced increased numbers of CD34(+)CD41(+) progenitors, megakaryocytes (MKs), and Plts. hESCs-WASKO-derived MKs and Plts showed altered phenotype as well as defective responses to agonist, mimicking WAS patients MKs and Plts defects. Interestingly, the defects were more evident in WASp-deficient MKs than in WASp-deficient Plts. Importantly, ectopic WAS expression using lentiviral vectors restored normal Plts development and MKs responses. These data validate the AND-1_WASKO cell lines as a human cellular model for basic research and for preclinical studies for WAS. PMID:26502776

  19. Total body irradiation, fludarabine, melphalan, and allogeneic hematopoietic stem cell transplantation for advanced pediatric hematologic malignancies.

    PubMed

    Petropoulos, D; Worth, L L; Mullen, C A; Madden, R; Mahajan, A; Choroszy, M; Ha, C S; Champlin, R C; Chan, K W

    2006-03-01

    We evaluated the efficacy and toxicity of adding 9 Gy of total body irradiation (TBI), in three single daily fractions of 3 Gy, to the reduced intensity regimen of fludarabine 30 mg/m2 i.v. x 4 days and melphalan 140 mg/m2 i.v. x 1 day in advanced pediatric hematologic malignancies. Twenty-two acute lymphoblastic leukemia (ALL), six acute myeloid leukemia (AML), and one non-Hodgkin lymphoma patients were transplanted. Of these, 13 were beyond second remission, and five had prior hematopoietic stem cell transplant (HSCT). Twenty-one donors were unrelated, of which 19 were from cord blood (CB) units. Three of the eight related donors were genotypically disparate. Oral mucositis and diarrhea were the most common toxicities. Twenty-seven patients achieved neutrophil engraftment (median 16 days), and 23 had platelet engraftment (median 42 days). One patient had primary graft failure. Seven patients died of non-relapse causes in the first 100 days. With a median follow-up of 52 months, seven of 22 ALL, five of six AML, and one of one lymphoma patients are alive and in remission. The regimen of TBI, fludarabine, and melphalan allows the engraftment of allogeneic hematopoietic stem cells (including mismatched CB). It was fairly well tolerated in pediatric patients, even for second transplants. Its efficacy requires further evaluation. PMID:16435013

  20. Transcriptional, epigenetic and retroviral signatures identify regulatory regions involved in hematopoietic lineage commitment

    PubMed Central

    Romano, Oriana; Peano, Clelia; Tagliazucchi, Guidantonio Malagoli; Petiti, Luca; Poletti, Valentina; Cocchiarella, Fabienne; Rizzi, Ermanno; Severgnini, Marco; Cavazza, Alessia; Rossi, Claudia; Pagliaro, Pasqualepaolo; Ambrosi, Alessandro; Ferrari, Giuliana; Bicciato, Silvio; De Bellis, Gianluca; Mavilio, Fulvio; Miccio, Annarita

    2016-01-01

    Genome-wide approaches allow investigating the molecular circuitry wiring the genetic and epigenetic programs of human somatic stem cells. Hematopoietic stem/progenitor cells (HSPC) give rise to the different blood cell types; however, the molecular basis of human hematopoietic lineage commitment is poorly characterized. Here, we define the transcriptional and epigenetic profile of human HSPC and early myeloid and erythroid progenitors by a combination of Cap Analysis of Gene Expression (CAGE), ChIP-seq and Moloney leukemia virus (MLV) integration site mapping. Most promoters and transcripts were shared by HSPC and committed progenitors, while enhancers and super-enhancers consistently changed upon differentiation, indicating that lineage commitment is essentially regulated by enhancer elements. A significant fraction of CAGE promoters differentially expressed upon commitment were novel, harbored a chromatin enhancer signature, and may identify promoters and transcribed enhancers driving cell commitment. MLV-targeted genomic regions co-mapped with cell-specific active enhancers and super-enhancers. Expression analyses, together with an enhancer functional assay, indicate that MLV integration can be used to identify bona fide developmentally regulated enhancers. Overall, this study provides an overview of transcriptional and epigenetic changes associated to HSPC lineage commitment, and a novel signature for regulatory elements involved in cell identity. PMID:27095295

  1. Absence of WASp Enhances Hematopoietic and Megakaryocytic Differentiation in a Human Embryonic Stem Cell Model

    PubMed Central

    Toscano, Miguel G; Muñoz, Pilar; Sánchez-Gilabert, Almudena; Cobo, Marién; Benabdellah, Karim; Anderson, Per; Ramos-Mejía, Verónica; Real, Pedro J; Neth, Olaf; Molinos-Quintana, Agueda; Gregory, Philip D; Holmes, Michael C; Martin, Francisco

    2016-01-01

    The Wiskott-Aldrich syndrome (WAS) is an X-linked primary immunodeficiency caused by mutations in the WAS gene and characterized by severe thrombocytopenia. Although the role of WASp in terminally differentiated lymphocytes and myeloid cells is well characterized, its role in early hematopoietic differentiation and in platelets (Plts) biology is poorly understood. In the present manuscript, we have used zinc finger nucleases targeted to the WAS locus for the development of two isogenic WAS knockout (WASKO) human embryonic stem cell lines (hESCs). Upon hematopoietic differentiation, hESCs-WASKO generated increased ratios of CD34+CD45+ progenitors with altered responses to stem cell factor compared to hESCs-WT. When differentiated toward the megakaryocytic linage, hESCs-WASKO produced increased numbers of CD34+CD41+ progenitors, megakaryocytes (MKs), and Plts. hESCs-WASKO-derived MKs and Plts showed altered phenotype as well as defective responses to agonist, mimicking WAS patients MKs and Plts defects. Interestingly, the defects were more evident in WASp-deficient MKs than in WASp-deficient Plts. Importantly, ectopic WAS expression using lentiviral vectors restored normal Plts development and MKs responses. These data validate the AND-1_WASKO cell lines as a human cellular model for basic research and for preclinical studies for WAS. PMID:26502776

  2. A diffusible signal derived from hematopoietic cells supports the survival and proliferation of regenerative cells during zebrafish fin fold regeneration.

    PubMed

    Hasegawa, Tomoya; Nakajima, Teruhiro; Ishida, Takashi; Kudo, Akira; Kawakami, Atsushi

    2015-03-01

    Multicellular organisms maintain body integrity by constantly regenerating tissues throughout their lives; however, the overall mechanism for regulating regeneration remains an open question. Studies of limb and fin regeneration in teleost fish and urodeles have shown the involvement of a number of locally activated signals at the wounded site during regeneration. Here, we demonstrate that a diffusible signal from a distance also play an essential role for regeneration. Among a number of zebrafish mutants, we found that the zebrafish cloche (clo) and tal1 mutants, which lack most hematopoietic tissues, displayed a unique regeneration defect accompanying apoptosis in primed regenerative tissue. Our analyses of the mutants showed that the cells in the primed regenerative tissue are susceptible to apoptosis, but their survival is normally supported by the presence of hematopoietic tissues, mainly the myeloid cells. We further showed that a diffusible factor in the wild-type body fluid mediates this signal. Thus, our study revealed a novel mechanism that the hematopoietic tissues regulate tissue regeneration through a diffusible signal. PMID:25533245

  3. Human and Murine Hematopoietic Stem Cell Aging Is Associated with Functional Impairments and Intrinsic Megakaryocytic/Erythroid Bias

    PubMed Central

    Rundberg Nilsson, Alexandra; Soneji, Shamit; Adolfsson, Sofia; Bryder, David; Pronk, Cornelis Jan

    2016-01-01

    Aging within the human hematopoietic system associates with various deficiencies and disease states, including anemia, myeloid neoplasms and reduced adaptive immune responses. Similar phenotypes are observed in mice and have been linked to alterations arising at the hematopoietic stem cell (HSC) level. Such an association is, however, less established in human hematopoiesis and prompted us here to detail characteristics of the most primitive human hematopoietic compartments throughout ontogeny. In addition, we also attempted to interrogate similarities between aging human and murine hematopoiesis. Coupled to the transition from human cord blood (CB) to young and aged bone marrow (BM), we observed a gradual increase in frequency of candidate HSCs. This was accompanied by functional impairments, including decreased lymphoid output and reduced proliferative potential. Downstream of human HSCs, we observed decreasing levels of common lymphoid progenitors (CLPs), and increasing frequencies of megakaryocyte/erythrocyte progenitors (MEPs) with age, which could be linked to changes in lineage-affiliated gene expression patterns in aged human HSCs. These findings were paralleled in mice. Therefore, our data support the notion that age-related changes also in human hematopoiesis involve the HSC pool, with a prominent skewing towards the megakaryocytic/erythroid lineages, and suggests conserved mechanisms underlying aging of the blood cell system. PMID:27368054

  4. Brief Report: Alternative Splicing of Extra Domain A (EIIIA) of Fibronectin Plays a Tissue-Specific Role in Hematopoietic Homeostasis.

    PubMed

    Malara, Alessandro; Gruppi, Cristian; Celesti, Giuseppe; Romano, Bina; Laghi, Luigi; De Marco, Luigi; Muro, Andrés F; Balduini, Alessandra

    2016-08-01

    Fibronectin (FN) is a major extracellular matrix protein implicated in cell adhesion and differentiation in the bone marrow (BM) environment. Alternative splicing of FN gene results in the generation of protein variants containing an additional EIIIA domain that sustains cell proliferation or differentiation during physiological or pathological tissue remodeling. To date its expression and role in adult hematopoiesis has not been explored. In our research, we demonstrate that during physiological hematopoiesis a small fraction of BM derived FN contains the EIIIA domain and that mice constitutively including (EIIIA(+/+) ) or excluding (EIIIA(-/-) ) the EIIIA exon present comparable levels of hematopoietic stem cells, myeloid and lymphoid progenitors within BM. Moreover, only minor alterations were detected in blood parameters and in hematopoietic frequencies of BM granulocytes/monocytes and B cells. As opposed to other tissues, unique compensatory mechanisms, such as increased FN accumulation and variable expression of the EIIIA receptors, Toll like receptor-4 and alpha9 integrin subunit, characterized the BM of these mice. Our data demonstrate that FN is a fundamental component of the hematopoietic tissue and that the EIIIA exon may play a key role in modulating hematopiesis in conditions of BM stress or diseases. Stem Cells 2016;34:2263-2268. PMID:27090359

  5. Global gene expression analyses of hematopoietic stem cell-like cell lines with inducible Lhx2 expression

    PubMed Central

    Richter, Karin; Wirta, Valtteri; Dahl, Lina; Bruce, Sara; Lundeberg, Joakim; Carlsson, Leif; Williams, Cecilia

    2006-01-01

    Background Expression of the LIM-homeobox gene Lhx2 in murine hematopoietic cells allows for the generation of hematopoietic stem cell (HSC)-like cell lines. To address the molecular basis of Lhx2 function, we generated HSC-like cell lines where Lhx2 expression is regulated by a tet-on system and hence dependent on the presence of doxycyclin (dox). These cell lines efficiently down-regulate Lhx2 expression upon dox withdrawal leading to a rapid differentiation into various myeloid cell types. Results Global gene expression of these cell lines cultured in dox was compared to different time points after dox withdrawal using microarray technology. We identified 267 differentially expressed genes. The majority of the genes overlapping with HSC-specific databases were those down-regulated after turning off Lhx2 expression and a majority of the genes overlapping with those defined as late progenitor-specific genes were the up-regulated genes, suggesting that these cell lines represent a relevant model system for normal HSCs also at the level of global gene expression. Moreover, in situ hybridisations of several genes down-regulated after dox withdrawal showed overlapping expression patterns with Lhx2 in various tissues during embryonic development. Conclusion Global gene expression analysis of HSC-like cell lines with inducible Lhx2 expression has identified genes putatively linked to self-renewal / differentiation of HSCs, and function of Lhx2 in organ development and stem / progenitor cells of non-hematopoietic origin. PMID:16600034

  6. Cytogenetic and molecular delineation of the smallest commonly deleted region of chromosome 5 in malignant myeloid diseases.

    PubMed Central

    Le Beau, M M; Espinosa, R; Neuman, W L; Stock, W; Roulston, D; Larson, R A; Keinanen, M; Westbrook, C A

    1993-01-01

    Loss of a whole chromosome 5 or a deletion of its long arm (5q) is a recurring abnormality in malignant myeloid neoplasms. To determine the location of genes on 5q that may be involved in leukemogenesis, we examined the deleted chromosome 5 homologs in a series of 135 patients with malignant myeloid diseases. By comparing the breakpoints, we identified a small segment of 5q, consisting of band 5q31, that was deleted in each patient. This segment has been termed the critical region. Distal 5q contains a number of genes encoding growth factors, hormone receptors, and proteins involved in signal transduction or transcriptional regulation. These include several genes that are good candidates for a tumor-suppressor gene, as well as the genes encoding five hematopoietic growth factors (CSF2, IL3, IL4, IL5, and IL9). By using fluorescence in situ hybridization, we have refined the localization of these genes to 5q31.1 and have determined the order of these genes and of other markers within 5q31. By hybridizing probes to metaphase cells with overlapping deletions involving 5q31, we have narrowed the critical region to a small segment of 5q31 containing the EGR1 gene. The five hematopoietic growth factor genes and seven other genes are excluded from this region. The EGR1 gene was not deleted in nine other patients with acute myeloid leukemia who did not have abnormalities of chromosome 5. By physical mapping, the minimum size of the critical region was estimated to be 2.8 megabases. This cytogenetic map of 5q31, together with the molecular characterization of the critical region, will facilitate the identification of a putative tumor-suppressor gene in this band. PMID:8516290

  7. Are hematopoietic stem cells involved in hepatocarcinogenesis?

    PubMed Central

    Antonino, Matteo; Del Prete, Valentina; Neve, Viviana; Scavo, Maria Principia; Barone, Michele

    2014-01-01

    The liver has three cell lineages able to proliferate after a hepatic injury: the mature hepatocyte, the ductular “bipolar” progenitor cell termed “oval cell” and the putative periductular stem cell. Hepatocytes can only produce other hepatocytes whereas ductular progenitor cells are considerate bipolar since they can give rise to biliary cells or hepatocytes. Periductular stem cells are rare in the liver, have a very long proliferation potential and may be multipotent, being this aspect still under investigation. They originate in the bone marrow since their progeny express genetic markers of donor hematopoietic cells after bone marrow transplantation. Since the liver is the hematopoietic organ of the fetus, it is possible that hematopoietic stem cells may reside in the liver of the adult. This assumption is proved by the finding that oval cells express hematopoietic markers like CD34, CD45, CD 109, Thy-1, c-kit, and others, which are also expressed by bone marrow-derived hematopoietic stem cells (BMSCs). Few and discordant studies have evaluated the role of BMSC in hepatocarcinogenesis so far and further studies in vitro and in vivo are warranted in order to definitively clarify such an issue. PMID:25202697

  8. Loss of sex chromosomes in the hematopoietic disorders: Questions, concerns and data interpretation

    SciTech Connect

    Slovak, M.L.

    1994-09-01

    The significance of sex chromosome aberrations in the hematopoietic disorders has not yet been defined. Interpretive problems stem from (1) the loss of a sex chromosome associated with aging, (2) sex chromosome loss as the sole aberration in leukemia is rare, (3) random -(X or Y) is observed frequently in bone marrow samples, and (4) constitutional sex chromosome anomalies must be ruled out in cancer and follow-up may not be possible. The COH database identified 41 patients (pts) with sex chromosome loss. Loss of a sex chromosome was common in myeloid disorders (21/41). In t(8;21) leukemia (n=10), -(X or Y) was a common secondary karyotypic change. Additionally, -Y was associated with clonal evolution in 2 Ph + CML pts. In 2 elderly pts with myeloid disorders, -(X or Y) was observed in complex karyotypes with dmins; however, in the lymphoproliferative disorders -(X or Y) was noted in elderly pts without apparent pathogenetic significance. Three pts had constitutional sex chromosome aberrations: CML in 45,X; ALL in 47, XXY; and RAEB-IT in mos45,X/46,XX. In the mos45,X/46,XX pt, the leukemic clone was associated with the 45,X line without other karyotypic changes. Non-clonal aberrations were observed in 11 cases; in 3 cases these non-clonal losses were observed in serial samples. In a sex-mismatched BMT case, -(X or Y) in 4 cells was one of the first pathogenetic signs of leukemia relapse. These data suggest (1) interpretation of sex chromosome loss in leukemia must be made with caution and after a baseline sample, (2) non-clonal aberrations should be recorded, and (3) -(X or Y) appears to have pathogenetic significance in the myeloid disorders. Multi-institutional studies are needed to define (1) the incidence of leukemia in pts with constitutional sex chromosome anomalies and (2) the incidence and significance of sex chromosome aberrations as the primary (sole) cytogenetic aberration in leukemia.

  9. Vascular niche promotes hematopoietic multipotent progenitor formation from pluripotent stem cells

    PubMed Central

    Gori, Jennifer L.; Butler, Jason M.; Chan, Yan-Yi; Chandrasekaran, Devikha; Poulos, Michael G.; Ginsberg, Michael; Nolan, Daniel J.; Elemento, Olivier; Wood, Brent L.; Adair, Jennifer E.; Rafii, Shahin; Kiem, Hans-Peter

    2015-01-01

    Pluripotent stem cells (PSCs) represent an alternative hematopoietic stem cell (HSC) source for treating hematopoietic disease. The limited engraftment of human PSC–derived (hPSC-derived) multipotent progenitor cells (MPP) has hampered the clinical application of these cells and suggests that MPP require additional cues for definitive hematopoiesis. We hypothesized that the presence of a vascular niche that produces Notch ligands jagged-1 (JAG1) and delta-like ligand-4 (DLL4) drives definitive hematopoiesis. We differentiated hes2 human embryonic stem cells (hESC) and Macaca nemestrina–induced PSC (iPSC) line-7 with cytokines in the presence or absence of endothelial cells (ECs) that express JAG1 and DLL4. Cells cocultured with ECs generated substantially more CD34+CD45+ hematopoietic progenitors compared with cells cocultured without ECs or with ECs lacking JAG1 or DLL4. EC-induced cells exhibited Notch activation and expressed HSC-specific Notch targets RUNX1 and GATA2. EC-induced PSC-MPP engrafted at a markedly higher level in NOD/SCID/IL-2 receptor γ chain–null (NSG) mice compared with cytokine-induced cells, and low-dose chemotherapy-based selection further increased engraftment. Long-term engraftment and the myeloid-to-lymphoid ratio achieved with vascular niche induction were similar to levels achieved for cord blood–derived MPP and up to 20-fold higher than those achieved with hPSC-derived MPP engraftment. Our findings indicate that endothelial Notch ligands promote PSC-definitive hematopoiesis and production of long-term engrafting CD34+ cells, suggesting these ligands are critical for HSC emergence. PMID:25664855

  10. Comparative analysis of the efficiency and specificity of myeloid-Cre deleting strains using ROSA-EYFP reporter mice.

    PubMed

    Abram, Clare L; Roberge, Gray L; Hu, Yongmei; Lowell, Clifford A

    2014-06-01

    Since the first example of conditional gene targeting in mice in 1994, the use of Cre recombinase and loxP flanked sequences has become an invaluable technique to generate tissue and temporal specific gene knockouts. The number of mouse strains expressing floxed-gene sequences, and tissue-specific or temporal-specific Cre-recombinase that have been reported in the literature has grown exponentially. However, increased use of this technology has highlighted several problems that can impact the interpretation of any phenotype observed in these mouse models. In particular, accurate knowledge of the specificity of Cre expression in each strain is critical in order to make conclusions about the role of specific cell types in the phenotypes observed. Cre-mediated deletion specificity and efficiency have been described in many different ways in the literature, making direct comparisons between these Cre strains impossible. Here we report crossing thirteen different myeloid-Cre mouse strains to ROSA-EYFP reporter mice and assaying YFP expression in a variety of naïve unstimulated hematopoietic cells, in parallel. By focusing on myeloid subsets, we directly compare the relative efficiency and specificity of myeloid deletion in these strains under steady-state conditions. PMID:24857755

  11. Comparative analysis of the efficiency and specificity of myeloid-Cre deleting strains using ROSA-EYFP reporter mice

    PubMed Central

    Abram, Clare L.; Roberge, Gray L.; Hu, Yongmei; Lowell, Clifford A.

    2014-01-01

    Since the first example of conditional gene targeting in mice in 1994, the use of Cre recombinase and loxP flanked sequences has become an invaluable technique to generate tissue and temporal specific gene knockouts. The number of mouse strains expressing floxed-gene sequences, and tissue-specific or temporal-specific Cre-recombinase that have been reported in the literature has grown exponentially. However, increased use of this technology has highlighted several problems that can impact the interpretation of any phenotype observed in these mouse models. In particular, accurate knowledge of the specificity of Cre expression in each strain is critical in order to make conclusions about the role of specific cell types in the phenotypes observed. Cre-mediated deletion specificity and efficiency has been described in many different ways in the literature, making direct comparisons between these Cre strains impossible. Here we report crossing thirteen different myeloid-Cre mouse strains to ROSA-EYFP reporter mice and assaying YFP expression in a variety of naïve unstimulated hematopoietic cells, in parallel. By focusing on myeloid subsets, we directly compare the relative efficiency and specificity of myeloid deletion in these strains under steady-state conditions. PMID:24857755

  12. High avidity myeloid leukemia-associated antigen-specific CD8+ T cells preferentially reside in the bone marrow

    PubMed Central

    Scheinberg, Phillip; Chattopadhyay, Pratip K.; Gostick, Emma; Ladell, Kristin; Roederer, Mario; Hensel, Nancy F.; Douek, Daniel C.; Barrett, A. John

    2009-01-01

    The activity of allogeneic CD8+ T cells specific for leukemia-associated antigens (LAAs) is thought to mediate, at least in part, the curative effects of hematopoietic stem cell transplantation (HSCT) in myeloid malignancies. However, the identity and nature of clinically relevant LAA-specific CD8+ T-cell populations have proven difficult to define. Here, we used a combination of coreceptor-mutated peptide-major histocompatibility complex class I (pMHCI) tetramers and polychromatic flow cytometry to examine the avidity profiles, phenotypic characteristics, and anatomical distribution of HLA A*0201-restricted CD8+ T-cell populations specific for LAAs that are over-expressed in myeloid leukemias. Remarkably, LAA-specific CD8+ T-cell populations, regardless of fine specificity, were confined almost exclusively to the bone marrow; in contrast, CD8+ T-cell populations specific for the HLA A*0201-restricted cytomegalovirus (CMV) pp65495-503 epitope were phenotypically distinct and evenly distributed between bone marrow and peripheral blood. Furthermore, bone marrow-resident LAA-specific CD8+ T cells frequently engaged cognate antigen with high avidity; notably, this was the case in all tested bone marrow samples derived from patients who achieved clinical remission after HSCT. These data suggest that concomitant examination of bone marrow specimens in patients with myeloid leukemias might yield more definitive information in the search for immunologic prognosticators of clinical outcome. PMID:18997173

  13. Targeting of folate receptor β on acute myeloid leukemia blasts with chimeric antigen receptor-expressing T cells.

    PubMed

    Lynn, Rachel C; Poussin, Mathilde; Kalota, Anna; Feng, Yang; Low, Philip S; Dimitrov, Dimiter S; Powell, Daniel J

    2015-05-28

    T cells expressing a chimeric antigen receptor (CAR) can produce dramatic results in lymphocytic leukemia patients; however, therapeutic strategies for myeloid leukemia remain limited. Folate receptor β (FRβ) is a myeloid-lineage antigen expressed on 70% of acute myeloid leukemia (AML) patient samples. Here, we describe the development and evaluation of the first CARs specific for human FRβ (m909) in vitro and in vivo. m909 CAR T cells exhibited selective activation and lytic function against engineered C30-FRβ as well as endogenous FRβ(+) AML cell lines in vitro. In mouse models of human AML, m909 CAR T cells mediated the regression of engrafted FRβ(+) THP1 AML in vivo. In addition, we demonstrated that treatment of AML with all-trans retinoic acid (ATRA) enhanced FRβ expression, resulting in improved immune recognition by m909 CAR T cells. Because many cell surface markers are shared between AML blasts and healthy hematopoietic stem and progenitor cells (HSCs), we evaluated FRβ expression and recognition of HSCs by CAR T cells. m909 CAR T cells were not toxic against healthy human CD34(+) HSCs in vitro. Our results indicate that FRβ is a promising target for CAR T-cell therapy of AML, which may be augmented by combination with ATRA. PMID:25887778

  14. Epigenetic therapy restores normal hematopoiesis in a zebrafish model of NUP98-HOXA9-induced myeloid disease.

    PubMed

    Deveau, A P; Forrester, A M; Coombs, A J; Wagner, G S; Grabher, C; Chute, I C; Léger, D; Mingay, M; Alexe, G; Rajan, V; Liwski, R; Hirst, M; Steigmaier, K; Lewis, S M; Look, A T; Berman, J N

    2015-10-01

    Acute myeloid leukemia (AML) occurs when multiple genetic aberrations alter white blood cell development, leading to hyperproliferation and arrest of cell differentiation. Pertinent animal models link in vitro studies with the use of new agents in clinical trials. We generated a transgenic zebrafish expressing human NUP98-HOXA9 (NHA9), a fusion oncogene found in high-risk AML. Embryos developed a preleukemic state with anemia and myeloid cell expansion, and adult fish developed a myeloproliferative neoplasm (MPN). We leveraged this model to show that NHA9 increases the number of hematopoietic stem cells, and that oncogenic function of NHA9 depends on downstream activation of meis1, the PTGS/COX pathway and genome hypermethylation through the DNA methyltransferase, dnmt1. We restored normal hematopoiesis in NHA9 embryos with knockdown of meis1 or dnmt1, as well as pharmacologic treatment with DNA (cytosine-5)-methyltransferase (DNMT) inhibitors or cyclo-oxygenase (COX) inhibitors. DNMT inhibitors reduced genome methylation to near normal levels. Strikingly, we discovered synergy when we combined sub-monotherapeutic doses of a histone deacetylase inhibitor plus either a DNMT inhibitor or COX inhibitor to block the effects of NHA9 on zebrafish blood development. Our work proposes novel drug targets in NHA9-induced myeloid disease, and suggests rational therapies by combining minimal doses of known bioactive compounds. PMID:26017032

  15. Distal regulation of c-myb expression during IL-6-induced differentiation in murine myeloid progenitor M1 cells.

    PubMed

    Zhang, Junfang; Han, Bingshe; Li, Xiaoxia; Bies, Juraj; Jiang, Penglei; Koller, Richard P; Wolff, Linda

    2016-01-01

    The c-Myb transcription factor is a major regulator that controls differentiation and proliferation of hematopoietic progenitor cells, which is frequently deregulated in hematological diseases, such as lymphoma and leukemia. Understanding of the mechanisms regulating the transcription of c-myb gene is challenging as it lacks a typical promoter and multiple factors are involved. Our previous studies identified some distal regulatory elements in the upstream regions of c-myb gene in murine myeloid progenitor M1 cells, but the detailed mechanisms still remain unclear. In the present study, we found that a cell differentiation-related DNase1 hypersensitive site is located at a -28k region upstream of c-myb gene and that transcription factors Hoxa9, Meis1 and PU.1 bind to the -28k region. Circular chromosome conformation capture (4C) assay confirmed the interaction between the -28k region and the c-myb promoter, which is supported by the enrichment of CTCF and Cohesin. Our analysis also points to a critical role for Hoxa9 and PU.1 in distal regulation of c-myb expression in murine myeloid cells and cell differentiation. Overexpression of Hoxa9 disrupted the IL-6-induced differentiation of M1 cells and upregulated c-myb expression through binding of the -28k region. Taken together, our results provide an evidence for critical role of the -28k region in distal regulatory mechanism for c-myb gene expression during differentiation of myeloid progenitor M1 cells. PMID:27607579

  16. Targeting of folate receptor β on acute myeloid leukemia blasts with chimeric antigen receptor–expressing T cells

    PubMed Central

    Lynn, Rachel C.; Poussin, Mathilde; Kalota, Anna; Feng, Yang; Low, Philip S.; Dimitrov, Dimiter S.

    2015-01-01

    T cells expressing a chimeric antigen receptor (CAR) can produce dramatic results in lymphocytic leukemia patients; however, therapeutic strategies for myeloid leukemia remain limited. Folate receptor β (FRβ) is a myeloid-lineage antigen expressed on 70% of acute myeloid leukemia (AML) patient samples. Here, we describe the development and evaluation of the first CARs specific for human FRβ (m909) in vitro and in vivo. m909 CAR T cells exhibited selective activation and lytic function against engineered C30-FRβ as well as endogenous FRβ+ AML cell lines in vitro. In mouse models of human AML, m909 CAR T cells mediated the regression of engrafted FRβ+ THP1 AML in vivo. In addition, we demonstrated that treatment of AML with all-trans retinoic acid (ATRA) enhanced FRβ expression, resulting in improved immune recognition by m909 CAR T cells. Because many cell surface markers are shared between AML blasts and healthy hematopoietic stem and progenitor cells (HSCs), we evaluated FRβ expression and recognition of HSCs by CAR T cells. m909 CAR T cells were not toxic against healthy human CD34+ HSCs in vitro. Our results indicate that FRβ is a promising target for CAR T-cell therapy of AML, which may be augmented by combination with ATRA. PMID:25887778

  17. Minimal PU.1 reduction induces a preleukemic state and promotes development of acute myeloid leukemia.

    PubMed

    Will, Britta; Vogler, Thomas O; Narayanagari, Swathi; Bartholdy, Boris; Todorova, Tihomira I; da Silva Ferreira, Mariana; Chen, Jiahao; Yu, Yiting; Mayer, Jillian; Barreyro, Laura; Carvajal, Luis; Neriah, Daniela Ben; Roth, Michael; van Oers, Johanna; Schaetzlein, Sonja; McMahon, Christine; Edelmann, Winfried; Verma, Amit; Steidl, Ulrich

    2015-10-01

    Modest transcriptional changes caused by genetic or epigenetic mechanisms are frequent in human cancer. Although loss or near-complete loss of the hematopoietic transcription factor PU.1 induces acute myeloid leukemia (AML) in mice, a similar degree of PU.1 impairment is exceedingly rare in human AML; yet, moderate PU.1 inhibition is common in AML patients. We assessed functional consequences of modest reductions in PU.1 expression on leukemia development in mice harboring DNA lesions resembling those acquired during human stem cell aging. Heterozygous deletion of an enhancer of PU.1, which resulted in a 35% reduction of PU.1 expression, was sufficient to induce myeloid-biased preleukemic stem cells and their subsequent transformation to AML in a DNA mismatch repair-deficient background. AML progression was mediated by inhibition of expression of a PU.1-cooperating transcription factor, Irf8. Notably, we found marked molecular similarities between the disease in these mice and human myelodysplastic syndrome and AML. This study demonstrates that minimal reduction of a key lineage-specific transcription factor, which commonly occurs in human disease, is sufficient to initiate cancer development, and it provides mechanistic insight into the formation and progression of preleukemic stem cells in AML. PMID:26343801

  18. The 2016 revision to the World Health Organization classification of myeloid neoplasms and acute leukemia.

    PubMed

    Arber, Daniel A; Orazi, Attilio; Hasserjian, Robert; Thiele, Jürgen; Borowitz, Michael J; Le Beau, Michelle M; Bloomfield, Clara D; Cazzola, Mario; Vardiman, James W

    2016-05-19

    The World Health Organization (WHO) classification of tumors of the hematopoietic and lymphoid tissues was last updated in 2008. Since then, there have been numerous advances in the identification of unique biomarkers associated with some myeloid neoplasms and acute leukemias, largely derived from gene expression analysis and next-generation sequencing that can significantly improve the diagnostic criteria as well as the prognostic relevance of entities currently included in the WHO classification and that also suggest new entities that should be added. Therefore, there is a clear need for a revision to the current classification. The revisions to the categories of myeloid neoplasms and acute leukemia will be published in a monograph in 2016 and reflect a consensus of opinion of hematopathologists, hematologists, oncologists, and geneticists. The 2016 edition represents a revision of the prior classification rather than an entirely new classification and attempts to incorporate new clinical, prognostic, morphologic, immunophenotypic, and genetic data that have emerged since the last edition. The major changes in the classification and their rationale are presented here. PMID:27069254

  19. MLL1 and DOT1L cooperate with meningioma-1 to induce acute myeloid leukemia.

    PubMed

    Riedel, Simone S; Haladyna, Jessica N; Bezzant, Matthew; Stevens, Brett; Pollyea, Daniel A; Sinha, Amit U; Armstrong, Scott A; Wei, Qi; Pollock, Roy M; Daigle, Scott R; Jordan, Craig T; Ernst, Patricia; Neff, Tobias; Bernt, Kathrin M

    2016-04-01

    Meningioma-1 (MN1) overexpression is frequently observed in patients with acute myeloid leukemia (AML) and is predictive of poor prognosis. In murine models, forced expression of MN1 in hematopoietic progenitors induces an aggressive myeloid leukemia that is strictly dependent on a defined gene expression program in the cell of origin, which includes the homeobox genes Hoxa9 and Meis1 as key components. Here, we have shown that this program is controlled by two histone methyltransferases, MLL1 and DOT1L, as deletion of either Mll1 or Dot1l in MN1-expressing cells abrogated the cell of origin-derived gene expression program, including the expression of Hoxa cluster genes. In murine models, genetic inactivation of either Mll1 or Dot1l impaired MN1-mediated leukemogenesis. We determined that HOXA9 and MEIS1 are coexpressed with MN1 in a subset of clinical MN1hi leukemia, and human MN1hi/HOXA9hi leukemias were sensitive to pharmacologic inhibition of DOT1L. Together, these data point to DOT1L as a potential therapeutic target in MN1hi AML. In addition, our findings suggest that epigenetic modulation of the interplay between an oncogenic lesion and its cooperating developmental program has therapeutic potential in AML. PMID:26927674

  20. Requirement for CDK6 in MLL-rearranged acute myeloid leukemia

    PubMed Central

    Placke, Theresa; Faber, Katrin; Nonami, Atsushi; Putwain, Sarah L.; Salih, Helmut R.; Heidel, Florian H.; Krämer, Alwin; Root, David E.; Barbie, David A.; Krivtsov, Andrei V.; Armstrong, Scott A.; Hahn, William C.; Huntly, Brian J.; Sykes, Stephen M.; Milsom, Michael D.; Scholl, Claudia

    2014-01-01

    Chromosomal rearrangements involving the H3K4 methyltransferase mixed-lineage leukemia (MLL) trigger aberrant gene expression in hematopoietic progenitors and give rise to an aggressive subtype of acute myeloid leukemia (AML). Insights into MLL fusion-mediated leukemogenesis have not yet translated into better therapies because MLL is difficult to target directly, and the identity of the genes downstream of MLL whose altered transcription mediates leukemic transformation are poorly annotated. We used a functional genetic approach to uncover that AML cells driven by MLL-AF9 are exceptionally reliant on the cell-cycle regulator CDK6, but not its functional homolog CDK4, and that the preferential growth inhibition induced by CDK6 depletion is mediated through enhanced myeloid differentiation. CDK6 essentiality is also evident in AML cells harboring alternate MLL fusions and a mouse model of MLL-AF9–driven leukemia and can be ascribed to transcriptional activation of CDK6 by mutant MLL. Importantly, the context-dependent effects of lowering CDK6 expression are closely phenocopied by a small-molecule CDK6 inhibitor currently in clinical development. These data identify CDK6 as critical effector of MLL fusions in leukemogenesis that might be targeted to overcome the differentiation block associated with MLL-rearranged AML, and underscore that cell-cycle regulators may have distinct, noncanonical, and nonredundant functions in different contexts. PMID:24764564

  1. Requirement for CDK6 in MLL-rearranged acute myeloid leukemia.

    PubMed

    Placke, Theresa; Faber, Katrin; Nonami, Atsushi; Putwain, Sarah L; Salih, Helmut R; Heidel, Florian H; Krämer, Alwin; Root, David E; Barbie, David A; Krivtsov, Andrei V; Armstrong, Scott A; Hahn, William C; Huntly, Brian J; Sykes, Stephen M; Milsom, Michael D; Scholl, Claudia; Fröhling, Stefan

    2014-07-01

    Chromosomal rearrangements involving the H3K4 methyltransferase mixed-lineage leukemia (MLL) trigger aberrant gene expression in hematopoietic progenitors and give rise to an aggressive subtype of acute myeloid leukemia (AML). Insights into MLL fusion-mediated leukemogenesis have not yet translated into better therapies because MLL is difficult to target directly, and the identity of the genes downstream of MLL whose altered transcription mediates leukemic transformation are poorly annotated. We used a functional genetic approach to uncover that AML cells driven by MLL-AF9 are exceptionally reliant on the cell-cycle regulator CDK6, but not its functional homolog CDK4, and that the preferential growth inhibition induced by CDK6 depletion is mediated through enhanced myeloid differentiation. CDK6 essentiality is also evident in AML cells harboring alternate MLL fusions and a mouse model of MLL-AF9-driven leukemia and can be ascribed to transcriptional activation of CDK6 by mutant MLL. Importantly, the context-dependent effects of lowering CDK6 expression are closely phenocopied by a small-molecule CDK6 inhibitor currently in clinical development. These data identify CDK6 as critical effector of MLL fusions in leukemogenesis that might be targeted to overcome the differentiation block associated with MLL-rearranged AML, and underscore that cell-cycle regulators may have distinct, noncanonical, and nonredundant functions in different contexts. PMID:24764564

  2. Bruceine D induces apoptosis in human chronic myeloid leukemia K562 cells via mitochondrial pathway

    PubMed Central

    Zhang, Jian-Ye; Lin, Min-Ting; Tung, Ho-Yi; Tang, Si-Li; Yi, Tao; Zhang, Ya-Zhou; Tang, Yi-Na; Zhao, Zhong-Zhen; Chen, Hu-Biao

    2016-01-01

    Chronic myeloid leukemia (CML), an acquired malignant myeloproliferative disorder of hematopoietic stem cells, is one of the three most common forms of leukemia. In this study, we investigated the effects of bruceine D, which have been isolated from Brucea javanica (L.) Merr. on human chronic myeloid leukemia K562 cells. MTT assay was used to evaluate cell growth inhibition. Flow cytometry was performed to analyze mitochondrial membrane potential (ΔΨm). Western blot was applied to detect expression of cytochrome c, caspases-9, -3, PARP and other proteins. Bruceine D exhibited potent cytotoxicity to K562 cells with IC50 of 6.37 ± 0.39 μM. It led to loss of ΔΨm, release of cytochrome c, activation of caspases-9, -3 and cleavage of PARP, which suggested that bruceine D induced apoptosis of K562 cells through mitochondrial pathway. In addition, bruceine D inhibited the phosphorylation of AKT and ERK. It’s indicative that the potent anticancer activity of bruceine D be related to MAPK and PI3K pathways. PMID:27186433

  3. MLL1 and DOT1L cooperate with meningioma-1 to induce acute myeloid leukemia

    PubMed Central

    Riedel, Simone S.; Haladyna, Jessica N.; Bezzant, Matthew; Stevens, Brett; Pollyea, Daniel A.; Sinha, Amit U.; Armstrong, Scott A.; Wei, Qi; Pollock, Roy M.; Daigle, Scott R.; Jordan, Craig T.; Ernst, Patricia; Bernt, Kathrin M.

    2016-01-01

    Meningioma-1 (MN1) overexpression is frequently observed in patients with acute myeloid leukemia (AML) and is predictive of poor prognosis. In murine models, forced expression of MN1 in hematopoietic progenitors induces an aggressive myeloid leukemia that is strictly dependent on a defined gene expression program in the cell of origin, which includes the homeobox genes Hoxa9 and Meis1 as key components. Here, we have shown that this program is controlled by two histone methyltransferases, MLL1 and DOT1L, as deletion of either Mll1 or Dot1l in MN1-expressing cells abrogated the cell of origin–derived gene expression program, including the expression of Hoxa cluster genes. In murine models, genetic inactivation of either Mll1 or Dot1l impaired MN1-mediated leukemogenesis. We determined that HOXA9 and MEIS1 are coexpressed with MN1 in a subset of clinical MN1hi leukemia, and human MN1hi/HOXA9hi leukemias were sensitive to pharmacologic inhibition of DOT1L. Together, these data point to DOT1L as a potential therapeutic target in MN1hi AML. In addition, our findings suggest that epigenetic modulation of the interplay between an oncogenic lesion and its cooperating developmental program has therapeutic potential in AML. PMID:26927674

  4. Runx1 repression by histone deacetylation is critical for Setbp1-induced mouse myeloid leukemia development

    PubMed Central

    Vishwakarma, Bandana A.; Nguyen, Nhu; Makishima, Hideki; Hosono, Naoko; Gudmundsson, Kristbjorn O.; Negi, Vijay; Oakley, Kevin; Han, Yufen; Przychodzen, Bartlomiej; Maciejewski, Jaroslaw P.; Du, Yang

    2015-01-01

    Abnormal activation of SETBP1 through overexpression or missense mutations is highly recurrent in various myeloid malignancies; however, it is unclear whether such activation alone is able to induce leukemia development. Here we show that Setbp1 overexpression in mouse bone marrow progenitors through retroviral transduction is capable of initiating leukemia development in irradiated recipient mice. Before leukemic transformation, Setbp1 overexpression significantly enhances the self-renewal of hematopoietic stem cells (HSCs) and expands granulocyte macrophage progenitors (GMPs). Interestingly, Setbp1 overexpression also causes transcriptional repression of critical hematopoiesis regulator gene Runx1 and this effect is crucial for Setbp1-induced transformation. Runx1 repression is induced by Setbp1-mediated recruitment of a nucleosome remodeling deacetylase (NuRD) complex to Runx1 promoters and can be reversed by treatment with histone deacetylase (HDAC) inhibitors Entinostat and Vorinostat. Moreover, treatment with these inhibitors caused efficient differentiation of Setbp1 activation-induced leukemia cells in vitro, and significantly extended the survival of mice transplanted with such leukemias, suggesting that HDAC inhibition could be an effective strategy for treating myeloid malignancies with SETBP1 activation. PMID:26205084

  5. DNA Methylation Profiles and Their Relationship with Cytogenetic Status in Adult Acute Myeloid Leukemia

    PubMed Central

    Alvarez, Sara; Suela, Javier; Valencia, Ana; Fernández, Agustín; Wunderlich, Mark; Agirre, Xabier; Prósper, Felipe; Martín-Subero, José Ignacio; Maiques, Alba; Acquadro, Francesco; Rodriguez Perales, Sandra; Calasanz, María José; Roman-Gómez, Jose; Siebert, Reiner; Mulloy, James C.; Cervera, José; Sanz, Miguel Angel; Esteller, Manel; Cigudosa, Juan C.

    2010-01-01

    Background Aberrant promoter DNA methylation has been shown to play a role in acute myeloid leukemia (AML) pathophysiology. However, further studies to discuss the prognostic value and the relationship of the epigenetic signatures with defined genomic rearrangements in acute myeloid leukemia are required. Methodology/Principal Findings We carried out high-throughput methylation profiling on 116 de novo AML cases and we validated the significant biomarkers in an independent cohort of 244 AML cases. Methylation signatures were associated with the presence of a specific cytogenetic status. In normal karyotype cases, aberrant methylation of the promoter of DBC1 was validated as a predictor of the disease-free and overall survival. Furthermore, DBC1 expression was significantly silenced in the aberrantly methylated samples. Patients with chromosome rearrangements showed distinct methylation signatures. To establish the role of fusion proteins in the epigenetic profiles, 20 additional samples of human hematopoietic stem/progenitor cells (HSPC) transduced with common fusion genes were studied and compared with patient samples carrying the same rearrangements. The presence of MLL rearrangements in HSPC induced the methylation profile observed in the MLL-positive primary samples. In contrast, fusion genes such as AML1/ETO or CBFB/MYH11 failed to reproduce the epigenetic signature observed in the patients. Conclusions/Significance Our study provides a comprehensive epigenetic profiling of AML, identifies new clinical markers for cases with a normal karyotype, and reveals relevant biological information related to the role of fusion proteins on the methylation signature. PMID:20808941

  6. The role of TLR8 signaling in acute myeloid leukemia differentiation.

    PubMed

    Ignatz-Hoover, J J; Wang, H; Moreton, S A; Chakrabarti, A; Agarwal, M K; Sun, K; Gupta, K; Wald, D N

    2015-04-01

    Acute myeloid leukemia (AML) is an aggressive disease with a poor 5-year survival of 21% that is characterized by the differentiation arrest of immature myeloid cells. For a rare subtype of AML (acute promyeloctyic leukemia, 5-10% of cases), all-trans retinoic acid therapy removes the differentiation block, yielding over a 90% cure rate. However, this treatment is not effective for the other 90-95% of AML patients, suggesting that new differentiation strategies are needed. Interestingly, differentiation is induced in normal hematopoietic cells through Toll-like receptor (TLR) stimulation and TLRs are expressed on AML cells. We present evidence that the TLR8 activation promotes AML differentiation and growth inhibition in a TLR8/MyD88/p38-dependent manner. We also show that that TLR7/TLR8 agonist, R848, considerably impairs the growth of human AML cells in immunodeficient mice. Our data suggests TLR8 activation has direct anti-leukemic effects independent of its immunomodulating properties that are currently under investigation for cancer therapy. Taken together, our results suggest that treatment with TLR8 agonists may be a promising new therapeutic strategy for AML. PMID:25283842

  7. Tumor regulation of myeloid-derived suppressor cell proliferation and trafficking.

    PubMed

    Younos, Ibrahim H; Dafferner, Alicia J; Gulen, Dumrul; Britton, Holly C; Talmadge, James E

    2012-07-01

    A stress response can induce myeloid progenitor cell (MPC) proliferation, mobilization, and extramedullary hematopoiesis (EMH) within lymphoid and parenchymal organs. Our studies using in vivo BrdU labeling, Ki-67 IHC staining, and carboxyfluorescein succinimidyl ester (CFSE) adoptive cell transfer revealed that spleens, rather than bone marrow (BM) and peripheral blood (PB), from 4T1 mammary tumor-bearing (TB) mice were the primary site of MPC proliferation. The resultant increase in MPCs was associated with tumor hematopoietic growth factor (GF) transcription, decreased apoptosis, as well as, prolonged survival of splenic MPCs. In naïve mice, i.v. injected CFSE-labeled MDSCs (myeloid-derived suppressor cells) initially accumulated in the lungs, while in TB mice, they rapidly sequestered in the spleen. In contrast, a few of the injected MDSCs and leukocytes arrested, proliferated, or accumulated in the marrow, tumor, or PB of TB mice. However, BrdU labeling revealed a significant demargination of proliferating splenic MPCs into the PB. In tumors, despite high GF transcript levels, we found that a high frequency of MDSCs was apoptotic. In summary, tumor growth and cytokines regulate MPC proliferation, trafficking, accumulation, apoptosis, and survival. PMID:22609473

  8. What Should You Ask Your Doctor about Chronic Myeloid Leukemia?

    MedlinePlus

    ... chronic myeloid leukemia? What should you ask your doctor about chronic myeloid leukemia? As you cope with ... need to have honest, open discussions with your doctor. You should feel free to ask any question ...

  9. Genetics Home Reference: cytogenetically normal acute myeloid leukemia

    MedlinePlus

    ... one form of a cancer of the blood-forming tissue (bone marrow) called acute myeloid leukemia. In ... 1 link) PubMed Sources for This Page Döhner H. Implication of the molecular characterization of acute myeloid ...

  10. Chemotherapy Plus Sargramostim in Treating Patients With Refractory Myeloid Cancer

    ClinicalTrials.gov

    2013-01-08

    Accelerated Phase Chronic Myelogenous Leukemia; Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Blastic Phase Chronic Myelogenous Leukemia; Chronic Myelomonocytic Leukemia; Chronic Phase Chronic Myelogenous Leukemia; Paroxysmal Nocturnal Hemoglobinuria; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Myeloid Leukemia; Refractory Anemia; Refractory Anemia With Ringed Sideroblasts; Relapsing Chronic Myelogenous Leukemia; Thrombocytopenia; Untreated Adult Acute Myeloid Leukemia

  11. What's New in Adult Acute Myeloid Leukemia Research and Treatment?

    MedlinePlus

    ... Topic Additional resources for acute myeloid leukemia What’s new in acute myeloid leukemia research and treatment? Researchers ... benefit from current treatments. Researchers are studying many new chemo drugs for use in AML, including: Sapacitabine, ...

  12. What's New in Chronic Myeloid Leukemia Research and Treatment?

    MedlinePlus

    ... Topic Additional resources for chronic myeloid leukemia What`s new in chronic myeloid leukemia research and treatment? Studies ... such as cyclosporine or hydroxychloroquine, with a TKI. New drugs for CML Because researchers now know the ...

  13. What Are the Risk Factors for Chronic Myeloid Leukemia?

    MedlinePlus

    ... of an atomic bomb blast or nuclear reactor accident) increases the risk of getting CML Age : The ... Myeloid (CML)? Causes, Risk Factors, and Prevention Early Detection, Diagnosis, and Staging Treating Leukemia - Chronic Myeloid (CML) ...

  14. Co-activation of AMPK and mTORC1 Induces Cytotoxicity in Acute Myeloid Leukemia.

    PubMed

    Sujobert, Pierre; Poulain, Laury; Paubelle, Etienne; Zylbersztejn, Florence; Grenier, Adrien; Lambert, Mireille; Townsend, Elizabeth C; Brusq, Jean-Marie; Nicodeme, Edwige; Decrooqc, Justine; Nepstad, Ina; Green, Alexa S; Mondesir, Johanna; Hospital, Marie-Anne; Jacque, Nathalie; Christodoulou, Alexandra; Desouza, Tiffany A; Hermine, Olivier; Foretz, Marc; Viollet, Benoit; Lacombe, Catherine; Mayeux, Patrick; Weinstock, David M; Moura, Ivan C; Bouscary, Didier; Tamburini, Jerome

    2015-06-01

    AMPK is a master regulator of cellular metabolism that exerts either oncogenic or tumor suppressor activity depending on context. Here, we report that the specific AMPK agonist GSK621 selectively kills acute myeloid leukemia (AML) cells but spares normal hematopoietic progenitors. This differential sensitivity results from a unique synthetic lethal interaction involving concurrent activation of AMPK and mTORC1. Strikingly, the lethality of GSK621 in primary AML cells and AML cell lines is abrogated by chemical or genetic ablation of mTORC1 signaling. The same synthetic lethality between AMPK and mTORC1 activation is established in CD34-positive hematopoietic progenitors by constitutive activation of AKT or enhanced in AML cells by deletion of TSC2. Finally, cytotoxicity in AML cells from GSK621 involves the eIF2α/ATF4 signaling pathway that specifically results from mTORC1 activation. AMPK activation may represent a therapeutic opportunity in mTORC1-overactivated cancers. PMID:26004183

  15. Loss of prolyl hydroxylase-2 in myeloid cells and T-lymphocytes impairs tumor development.

    PubMed

    Mamlouk, Soulafa; Kalucka, Joanna; Singh, Rashim Pal; Franke, Kristin; Muschter, Antje; Langer, Anika; Jakob, Christiane; Gassmann, Max; Baretton, Gustavo B; Wielockx, Ben

    2014-02-15

    The tumor microenvironment plays a pivotal role during cancer development and progression. The balance between suppressive and cytotoxic responses of the tumor immune microenvironment has been shown to have a direct effect on the final outcome in various human and experimental tumors. Recently, we demonstrated that the oxygen sensor HIF-prolyl hydroxylase-2 (PHD2) plays a detrimental role in tumor cells, stimulating systemic growth and metastasis in mice. In our current study, we show that the conditional ablation of PHD2 in the hematopoietic system also leads to reduced tumor volume, intriguingly generated by an imbalance between enhanced cell death and improved proliferation of tumor cells. This effect seems to rely on the overall downregulation of protumoral as well as antitumoral cytokines. Using different genetic approaches, we were able to confine this complex phenotype to the crosstalk of PHD2-deficient myeloid cells and T-lymphocytes. Taken together, our findings reveal a multifaceted role for PHD2 in several hematopoietic lineages during tumor development and might have important implications for the development of tumor therapies in the future. PMID:23913502

  16. Engineering humanized mice for improved hematopoietic reconstitution

    PubMed Central

    Drake, Adam C; Chen, Qingfeng; Chen, Jianzhu

    2012-01-01

    Humanized mice are immunodeficient animals engrafted with human hematopoietic stem cells that give rise to various lineages of human blood cells throughout the life of the mouse. This article reviews recent advances in the generation of humanized mice, focusing on practical considerations. We discuss features of different immunodeficient recipient mouse strains, sources of human hematopoietic stem cells, advances in expansion and genetic modification of hematopoietic stem cells, and techniques to modulate the cytokine environment of recipient mice, in order to enhance reconstitution of specific human blood lineage cells. We highlight the opportunities created by new technologies and discuss practical considerations on how to make best use of the widening array of basic models for specific research applications. PMID:22425741

  17. Long noncoding RNAs in hematopoietic malignancies.

    PubMed

    Rodríguez-Malavé, Norma I; Rao, Dinesh S

    2016-05-01

    Recent years have witnessed the discovery of several classes of noncoding RNAs (ncRNAs), which are indispensable for the regulation of cellular processes. Many of these RNAs are regulatory in nature with functions in gene expression regulation such as piwi-interacting RNAs, small interfering RNAs and micro RNAs. Long noncoding RNAs (lncRNAs) comprise the most recently characterized class. LncRNAs are involved in transcriptional regulation, chromatin remodeling, imprinting, splicing, and translation, among other critical functions in the cell. Recent studies have elucidated the importance of lncRNAs in hematopoietic development. Dysregulation of lncRNA expression is a feature of various diseases and cancers, and is also seen in hematopoietic malignancies. This article focuses on lncRNAs that have been implicated in the pathogenesis of hematopoietic malignancies. PMID:26612601

  18. Molecular Pathology: Prognostic and Diagnostic Genomic Markers for Myeloid Neoplasms.

    PubMed

    Kuo, Frank C

    2016-09-01

    Application of next-generation sequencing (NGS) on myeloid neoplasms has expanded our knowledge of genomic alterations in this group of diseases. Genomic alterations in myeloid neoplasms are complex, heterogeneous, and not specific to a disease entity. NGS-based panel testing of myeloid neoplasms can complement existing diagnostic modalities and is gaining acceptance in the clinics and diagnostic laboratories. Prospective, randomized trials to evaluate the prognostic significance of genomic markers in myeloid neoplasms are under way in academic medical centers. PMID:27523973

  19. t(6;9)(p22;q34)/DEK-NUP214-rearranged pediatric myeloid leukemia: an international study of 62 patients

    PubMed Central

    Sandahl, Julie Damgaard; Coenen, Eva A.; Forestier, Erik; Harbott, Jochen; Johansson, Bertil; Kerndrup, Gitte; Adachi, Souichi; Auvrignon, Anne; Beverloo, H. Berna; Cayuela, Jean-Michel; Chilton, Lucy; Fornerod, Maarten; de Haas, Valérie; Harrison, Christine J.; Inaba, Hiroto; Kaspers, Gertjan J.L.; Liang, Der-Cherng; Locatelli, Franco; Masetti, Riccardo; Perot, Christine; Raimondi, Susana C.; Reinhardt, Katarina; Tomizawa, Daisuke; von Neuhoff, Nils; Zecca, Marco; Zwaan, C. Michel; van den Heuvel-Eibrink, Marry M.; Hasle, Henrik

    2014-01-01

    Acute myeloid leukemia with t(6;9)(p22;q34) is listed as a distinct entity in the 2008 World Health Organization classification, but little is known about the clinical implications of t(6;9)-positive myeloid leukemia in children. This international multicenter study presents the clinical and genetic characteristics of 62 pediatric patients with t(6;9)/DEK-NUP214-rearranged myeloid leukemia; 54 diagnosed as having acute myeloid leukemia, representing <1% of all childhood acute myeloid leukemia, and eight as having myelodysplastic syndrome. The t(6;9)/DEK-NUP214 was associated with relatively late onset (median age 10.4 years), male predominance (sex ratio 1.7), French-American-British M2 classification (54%), myelodysplasia (100%), and FLT3-ITD (42%). Outcome was substantially better than previously reported with a 5-year event-free survival of 32%, 5-year overall survival of 53%, and a 5-year cumulative incidence of relapse of 57%. Hematopoietic stem cell transplantation in first complete remission improved the 5-year event-free survival compared with chemotherapy alone (68% versus 18%; P<0.01) but not the overall survival (68% versus 54%; P=0.48). The presence of FLT3-ITD had a non-significant negative effect on 5-year overall survival compared with non-mutated cases (22% versus 62%; P=0.13). Gene expression profiling showed a unique signature characterized by significantly higher expression of EYA3, SESN1, PRDM2/RIZ, and HIST2H4 genes. In conclusion, t(6;9)/DEK-NUP214 represents a unique subtype of acute myeloid leukemia with a high risk of relapse, high frequency of FLT3-ITD, and a specific gene expression signature. PMID:24441146

  20. Phase I Combination of Midostaurin, Bortezomib, and Chemo in Relapsed/Refractory Acute Myeloid Leukemia

    ClinicalTrials.gov

    2016-04-05

    Acute Myeloid Leukemia; Acute Myeloid Leukemia With Multilineage Dysplasia Following; Myelodysplastic Syndrome; Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Recurrent Adult Acute Myeloid Leukemia; Secondary Acute Myeloid Leukemia

  1. Extramedullary blast crisis as initial presentation in chronic myeloid leukemia with the e1a2 BCR-ABL1 transcript: A case report

    PubMed Central

    AI, DI; LIU, WEI; LU, GARY; PATEL, KEYUR PRAVINCHANDRA; CHEN, ZI

    2015-01-01

    A 23-year-old woman presented with enlarged right inguinal lymph nodes. The pathological examination of the nodes revealed infiltration by myeloid sarcoma. A bone marrow smear and biopsy revealed cytogenetic abnormalities, with 46,XX,t(9;22) and chronic myeloid leukemia (CML) was diagnosed. The e1a2 BCR-ABL1 fusion transcript was detected. The patient received imatinib-based combined chemotherapy, allogeneic hematopoietic stem cell transplantation, donor lymphocyte infusions and dasatinib treatment. The patient achieved complete response and has remained leukemia-free for >48 months. To the best of our knowledge, this is the first case report of CML with the e1a2 BCR-ABL1 transcript, with extramedullary blast crisis as the initial presentation. The aim of the present study was to discuss this special case with reference to the literature. PMID:26807241

  2. A New Triggering Receptor Expressed on Myeloid Cells (TREM) Family Member, TLT-6, is Involved in Activation and Proliferation of Macrophages

    PubMed Central

    Won, Kyung-Jong; Park, Sung-Won; Lee, Seunghoon; Kong, Il-Keun; Chae, Jung-Il; Kim, Bokyung; Lee, Eun-Jong

    2015-01-01

    The triggering receptor expressed on myeloid cells (TREM) family, which is abundantly expressed in myeloid lineage cells, plays a pivotal role in innate and adaptive immune response. In this study, we aimed to identify a novel receptor expressed on hematopoietic stem cells (HSCs) by using in silico bioinformatics and to characterize the identified receptor. We thus found the TREM-like transcript (TLT)-6, a new member of TREM family. TLT-6 has a single immunoglobulin domain in the extracellular region and a long cytoplasmic region containing 2 immunoreceptor tyrosine-based inhibitory motif-like domains. TLT-6 transcript was expressed in HSCs, monocytes and macrophages. TLT-6 protein was up-regulated on the surface of bone marrow-derived and peritoneal macrophages by lipopolysaccharide stimulation. TLT-6 exerted anti-proliferative effects in macrophages. Our results demonstrate that TLT-6 may regulate the activation and proliferation of macrophages. PMID:26557807

  3. The analysis of novel distal Cebpa enhancers and silencers using a transcriptional model reveals the complex regulatory logic of hematopoietic lineage specification.

    PubMed

    Bertolino, Eric; Reinitz, John; Manu

    2016-05-01

    C/EBPα plays an instructive role in the macrophage-neutrophil cell-fate decision and its expression is necessary for neutrophil development. How Cebpa itself is regulated in the myeloid lineage is not known. We decoded the cis-regulatory logic of Cebpa, and two other myeloid transcription factors, Egr1 and Egr2, using a combined experimental-computational approach. With a reporter design capable of detecting both distal enhancers and silencers, we analyzed 46 putative cis-regulatory modules (CRMs) in cells representing myeloid progenitors, and derived early macrophages or neutrophils. In addition to novel enhancers, this analysis revealed a surprisingly large number of silencers. We determined the regulatory roles of 15 potential transcriptional regulators by testing 32,768 alternative sequence-based transcriptional models against CRM activity data. This comprehensive analysis allowed us to infer the cis-regulatory logic for most of the CRMs. Silencer-mediated repression of Cebpa was found to be effected mainly by TFs expressed in non-myeloid lineages, highlighting a previously unappreciated contribution of long-distance silencing to hematopoietic lineage resolution. The repression of Cebpa by multiple factors expressed in alternative lineages suggests that hematopoietic genes are organized into densely interconnected repressive networks instead of hierarchies of mutually repressive pairs of pivotal TFs. More generally, our results demonstrate that de novo cis-regulatory dissection is feasible on a large scale with the aid of transcriptional modeling. Current address: Department of Biology, University of North Dakota, 10 Cornell Street, Stop 9019, Grand Forks, ND 58202-9019, USA. PMID:26945717

  4. Targeting mitochondrial RNA polymerase in acute myeloid leukemia

    PubMed Central

    Bralha, Fernando N.; Liyanage, Sanduni U.; Hurren, Rose; Wang, Xiaoming; Son, Meong Hi; Fung, Thomas A.; Chingcuanco, Francine B.; Tung, Aveline Y. W.; Andreazza, Ana C.; Psarianos, Pamela; Schimmer, Aaron D.; Salmena, Leonardo; Laposa, Rebecca R.

    2015-01-01

    Acute myeloid leukemia (AML) cells have high oxidative phosphorylation and mitochondrial mass and low respiratory chain spare reserve capacity. We reasoned that targeting the mitochondrial RNA polymerase (POLRMT), which indirectly controls oxidative phosphorylation, represents a therapeutic strategy for AML. POLRMT-knockdown OCI-AML2 cells exhibited decreased mitochondrial gene expression, decreased levels of assembled complex I, decreased levels of mitochondrially-encoded Cox-II and decreased oxidative phosphorylation. POLRMT-knockdown cells exhibited an increase in complex II of the electron transport chain, a complex comprised entirely of subunits encoded by nuclear genes, and POLRMT-knockdown cells were resistant to a complex II inhibitor theonyltrifluoroacetone. POLRMT-knockdown cells showed a prominent increase in cell death. Treatment of OCI-AML2 cells with 10-50 μM 2-C-methyladenosine (2-CM), a chain terminator of mitochondrial transcription, reduced mitochondrial gene expression and oxidative phosphorylation, and increased cell death in a concentration-dependent manner. Treatment of normal human hematopoietic cells with 2-CM at concentrations of up to 100 μMdid not alter clonogenic growth, suggesting a therapeutic window. In an OCI-AML2 xenograft model, treatment with 2-CM (70 mg/kg, i.p., daily) decreased the volume and mass of tumours to half that of vehicle controls. 2-CM did not cause toxicity to major organs. Overall, our results in a preclinical model contribute to the functional validation of the utility of targeting the mitochondrial RNA polymerase as a therapeutic strategy for AML. PMID:26484416

  5. Chronic Myeloid Leukemia (CML) Mouse Model in Translational Research.

    PubMed

    Peng, Cong; Li, Shaoguang

    2016-01-01

    Chronic myeloid leukemia (CML) is a myeloproliferative disorder characterized by increased proliferation of granulocytic cells without the loss of their capability to differentiate. CML is a clonal disease, originated at the level of Hematopoietic Stem Cells with the Philadelphia chromosome resulting from a reciprocal translocation between the chromosomes 9 and 22t(9;22)-(q34;q11). This translocation produces a fusion gene known as BCR-ABL which acquires uncontrolled tyrosine kinase activity, constantly turning on its downstream signaling molecules/pathways, and promoting proliferation of leukemia cell through anti-apoptosis and acquisition of additional mutations. To evaluate the role of each critical downstream signaling molecule of BCR-ABL and test therapeutic drugs in vivo, it is important to use physiological mouse disease models. Here, we describe a mouse model of CML induced by BCR-ABL retrovirus (MSCV-BCR-ABL-GFP; MIG-BCR-ABL) and how to use this model in translational research.Moreover, to expand the application of this retrovirus induced CML model in a lot of conditional knockout mouse strain, we modified this vector to a triple gene coexpression vector in which we can co-express BCR-ABL, GFP, and a third gene which will be tested in different systems. To apply this triple gene system in conditional gene knockout strains, we can validate the CML development in the knockout mice and trace the leukemia cell following the GFP marker. In this protocol, we also describe how we utilize this triple gene system to prove the function of Pten as a tumor suppressor in leukemogenesis. Overall, this triple gene system expands our research spectrum in current conditional gene knockout strains and benefits our CML translational research. PMID:27150093

  6. Epigenetic regulators as promising therapeutic targets in acute myeloid leukemia

    PubMed Central

    Gallipoli, Paolo; Giotopoulos, George

    2015-01-01

    Acute myeloid leukemia (AML), the most prevalent acute leukemia in adults, is an aggressive hematological malignancy arising in hematopoietic stem and progenitor cells. With the exception of a few specific AML subtypes, the mainstays of treatment have not significantly changed over the last 20 years, and are still based on standard cytotoxic chemotherapy. As a result, clinical outcome remains poor for the majority of patients, with overall long-term survival in the region of 20–30%. Recent successes in characterizing the genetic landscape of AML have highlighted that, despite its heterogeneity, many cases of AML carry recurrent mutations in genes encoding epigenetic regulators. Transcriptional dysregulation and altered epigenetic function have therefore emerged as exciting areas in AML research and it is becoming increasingly clear that epigenetic dysfunction is central to leukemogenesis in AML. This has subsequently paved the way for the development of epigenetically targeted therapies. In this review, we will discuss the most recent advances in our understanding of the role of epigenetic dysregulation in AML pathobiology. We will particularly focus on those altered epigenetic programs that have been shown to be central to the development and maintenance of AML in preclinical models. We will discuss the recent development of therapeutics specifically targeting these key epigenetic programs in AML, describe their mechanism of action and present their current clinical development. Finally, we will discuss the opportunities presented by epigenetically targeted therapy in AML and will highlight future challenges ahead for the AML community, to ensure that these novel therapeutics are optimally translated into clinical practice and result in clinical improvement for AML patients. PMID:26137202

  7. Role of calcium-dependent protein kinases in chronic myeloid leukemia: combined effects of PKC and BCR-ABL signaling on cellular alterations during leukemia development

    PubMed Central

    Mencalha, André L; Corrêa, Stephany; Abdelhay, Eliana

    2014-01-01

    Calcium-dependent protein kinases (PKCs) function in a myriad of cellular processes, including cell-cycle regulation, proliferation, hematopoietic stem cell differentiation, apoptosis, and malignant transformation. PKC inhibitors, when targeted to these pathways, have demonstrated efficacy against several types of solid tumors as well as leukemia. Chronic myeloid leukemia (CML) represents 20% of all adult leukemia. The aberrant Philadelphia chromosome has been reported as the main cause of CML development in hematopoietic stem cells, due to the formation of the BCR-ABL oncogene. PKCs and BCR-ABL coordinate several signaling pathways that are crucial to cellular malignant transformation. Experimental and clinical evidence suggests that pharmacological approaches using PKC inhibitors may be effective in the treatment of CML. This mini review summarizes articles from the National Center for Biotechnology Information website that have shown evidence of the involvement of PKC in CML. PMID:25045273

  8. Deletion of Pten in CD45-expressing cells leads to development of T-cell lymphoblastic lymphoma but not myeloid malignancies

    PubMed Central

    Mirantes, Cristina; Dosil, Maria Alba; Hills, David; Yang, Jian; Eritja, Núria; Santacana, Maria; Gatius, Sònia; Vilardell, Felip; Medvinsky, Alexander; Matias-Guiu, Xavier

    2016-01-01

    Since its discovery in the late 1990s, Pten has turned out to be one of the most important tumor suppressor genes. Pten loss results in increased activation of the phosphatidylinositol 3-kinase/Akt signaling pathway, which is associated with increased proliferation, survival, and neoplastic growth. Here, we have addressed the effects of conditional deletion of Pten in hematopoietic cells by crossing Pten conditional knockout mice with a knock-in mouse expressing the Cre recombinase in the CD45 locus. CD45 is also known as leukocyte common antigen, and it is expressed in virtually all white cells and in hematopoietic stem cells. Using a reporter mouse, we demonstrate that CD45:Cre mouse displays recombinase activity in both myeloid and lymphoid cells. However, deletion of Pten in CD45-expressing cells induces development of T-cell acute lymphoblastic leukemia and lymphoma, but not other hematologic malignancies. PMID:26773036

  9. Deletion of Pten in CD45-expressing cells leads to development of T-cell lymphoblastic lymphoma but not myeloid malignancies.

    PubMed

    Mirantes, Cristina; Dosil, Maria Alba; Hills, David; Yang, Jian; Eritja, Núria; Santacana, Maria; Gatius, Sònia; Vilardell, Felip; Medvinsky, Alexander; Matias-Guiu, Xavier; Dolcet, Xavier

    2016-04-14

    Since its discovery in the late 1990s, Pten has turned out to be one of the most important tumor suppressor genes. Pten loss results in increased activation of the phosphatidylinositol 3-kinase/Akt signaling pathway, which is associated with increased proliferation, survival, and neoplastic growth. Here, we have addressed the effects of conditional deletion of Pten in hematopoietic cells by crossing Pten conditional knockout mice with a knock-in mouse expressing the Cre recombinase in the CD45 locus. CD45 is also known as leukocyte common antigen, and it is expressed in virtually all white cells and in hematopoietic stem cells. Using a reporter mouse, we demonstrate that CD45:Cre mouse displays recombinase activity in both myeloid and lymphoid cells. However, deletion of Pten in CD45-expressing cells induces development of T-cell acute lymphoblastic leukemia and lymphoma, but not other hematologic malignancies. PMID:26773036

  10. In utero hematopoietic cell transplantation for hemoglobinopathies

    PubMed Central

    Derderian, S. Christopher; Jeanty, Cerine; Walters, Mark C.; Vichinsky, Elliott; MacKenzie, Tippi C.

    2014-01-01

    In utero hematopoietic cell transplantation (IUHCTx) is a promising strategy to circumvent the challenges of postnatal hematopoietic stem cell (HSC) transplantation. The goal of IUHCTx is to introduce donor cells into a naïve host prior to immune maturation, thereby inducing donor–specific tolerance. Thus, this technique has the potential of avoiding host myeloablative conditioning with cytotoxic agents. Over the past two decades, several attempts at IUHCTx have been made to cure numerous underlying congenital anomalies with limited success. In this review, we will briefly review the history of IUHCTx and give a perspective on alpha thalassemia major, one target disease for its clinical application. PMID:25628564

  11. Tet2 facilitates the de-repression of myeloid target genes during C/EBPa induced transdifferentiation of pre-B cells

    PubMed Central

    Kallin, Eric M.; Rodríguez-Ubreva, Javier; Christensen, J esper; Cimmino, Luisa; Aifantis, Iannis; Helin, Kristian; Ballestar, Esteban; Graf, Thomas

    2013-01-01

    SUMMARY The methylcytosine hydroxylase Tet2 has been implicated in hematopoietic differentiation and the formation of myeloid malignancies when mutated. An ideal system to study the role of Tet2 in myelopoeisis is C/EBPa induced transdifferentiation of pre-B cells into macrophages. Here we found that C/EBPa binds to upstream regions of Tet2 and that the gene becomes activated. Tet2 knockdowns impaired the upregulation of macrophage markers as well as phagocytic capacity, suggesting that the enzyme is required for both early and late stage myeloid differentiation. A slightly weaker effect was seen in primary cells with a Tet2 ablation. Expression arrays of transdifferentiating cells with Tet2 knockdowns permitted the identification of a small subset of myeloid genes whose upregulation was blunted. Activation of these target genes was accompanied by rapid increases of promoter hydroxy-methylation. Our observations indicate that Tet2 helps C/EBPa rapidly de-repress myeloid genes during the conversion of pre-B cells into macrophages. PMID:22981865

  12. Myeloid Sarcoma in an Eyelid That Developed during Chemotherapy for Acute Myeloid Leukemia.

    PubMed

    Kang, Hyera; Takahashi, Yasuhiro; Takahashi, Emiko; Kakizaki, Hirohiko

    2016-01-01

    An 80-year-old female presented with a mass in the left upper eyelid margin that had developed during chemotherapy for acute myeloid leukemia. The mass was elastic, hard, and pinkish, with a relatively smooth surface but without madarosis. The histopathological findings corresponded to a myeloid sarcoma. No blast cells were shown in the peripheral blood at the time of biopsy, and she subsequently underwent an azacitidine injection regimen. The size of the eyelid tumor decreased 3 months after the biopsy, when the course of azacitidine injections was completed. However, acute myeloid leukemia recurred, and the patient died. PMID:26889156

  13. Myeloid Sarcoma in an Eyelid That Developed during Chemotherapy for Acute Myeloid Leukemia

    PubMed Central

    Kang, Hyera; Takahashi, Yasuhiro; Takahashi, Emiko; Kakizaki, Hirohiko

    2016-01-01

    An 80-year-old female presented with a mass in the left upper eyelid margin that had developed during chemotherapy for acute myeloid leukemia. The mass was elastic, hard, and pinkish, with a relatively smooth surface but without madarosis. The histopathological findings corresponded to a myeloid sarcoma. No blast cells were shown in the peripheral blood at the time of biopsy, and she subsequently underwent an azacitidine injection regimen. The size of the eyelid tumor decreased 3 months after the biopsy, when the course of azacitidine injections was completed. However, acute myeloid leukemia recurred, and the patient died PMID:26889156

  14. Vaccines as consolidation therapy for myeloid leukemia

    PubMed Central

    Alatrash, Gheath; Molldrem, Jeffrey J

    2011-01-01

    Immunotherapy for myeloid leukemias remains a cornerstone in the management of this highly aggressive group of malignancies. Allogeneic (allo) stem cell transplantation (SCT), which can be curative in acute and chronic myeloid leukemias, exemplifies the success of immunotherapy for cancer management. However, because of its nonspecific immune response against normal tissue, allo-SCT is associated with high rates of morbidity and mortality, secondary to graft-versus-host disease, which can occur in up to 50% of allo-SCT recipients. Targeted immunotherapy using leukemia vaccines has been heavily investigated, as these vaccines elicit specific immune responses against leukemia cells while sparing normal tissue. Peptide and cellular vaccines have been developed against tumor-specific and leukemia-associated self-antigens. Although not yet considered the standard of care, leukemia vaccines continue to show promising results in the management of the myeloid leukemias. PMID:21322777

  15. Novel drug therapies in myeloid leukemia.

    PubMed

    Horne, Gillian A; Kinstrie, Ross; Copland, Mhairi

    2015-01-01

    Both acute myeloid leukemia and chronic myeloid leukemia are thought to arise from a subpopulation of primitive cells, termed leukemic stem cells that share properties with somatic stem cells. Leukemic stem cells are capable of continued self-renewal, and are resistant to conventional chemotherapy and are considered to be responsible for disease relapse. In recent years, improved understanding of the underlying mechanisms of myeloid leukemia biology has led to the development of novel and targeted therapies. This review focuses on clinically relevant patent applications and their relevance within the known literature in two areas of prevailing therapeutic interest, namely monoclonal antibody therapy and small molecule inhibitors in disease-relevant signaling pathways. PMID:26030080

  16. MicroRNA-126-mediated control of cell fate in B-cell myeloid progenitors as a potential alternative to transcriptional factors.

    PubMed

    Okuyama, Kazuki; Ikawa, Tomokatsu; Gentner, Bernhard; Hozumi, Katsuto; Harnprasopwat, Ratanakanit; Lu, Jun; Yamashita, Riu; Ha, Daon; Toyoshima, Takae; Chanda, Bidisha; Kawamata, Toyotaka; Yokoyama, Kazuaki; Wang, Shusheng; Ando, Kiyoshi; Lodish, Harvey F; Tojo, Arinobu; Kawamoto, Hiroshi; Kotani, Ai

    2013-08-13

    Lineage specification is thought to be largely regulated at the level of transcription, where lineage-specific transcription factors drive specific cell fates. MicroRNAs (miR), vital to many cell functions, act posttranscriptionally to decrease the expression of target mRNAs. MLL-AF4 acute lymphocytic leukemia exhibits both myeloid and B-cell surface markers, suggesting that the transformed cells are B-cell myeloid progenitor cells. Through gain- and loss-of-function experiments, we demonstrated that microRNA 126 (miR-126) drives B-cell myeloid biphenotypic leukemia differentiation toward B cells without changing expression of E2A immunoglobulin enhancer-binding factor E12/E47 (E2A), early B-cell factor 1 (EBF1), or paired box protein 5, which are critical transcription factors in B-lymphopoiesis. Similar induction of B-cell differentiation by miR-126 was observed in normal hematopoietic cells in vitro and in vivo in uncommitted murine c-Kit(+)Sca1(+)Lineage(-) cells, with insulin regulatory subunit-1 acting as a target of miR-126. Importantly, in EBF1-deficient hematopoietic progenitor cells, which fail to differentiate into B cells, miR-126 significantly up-regulated B220, and induced the expression of B-cell genes, including recombination activating genes-1/2 and CD79a/b. These data suggest that miR-126 can at least partly rescue B-cell development independently of EBF1. These experiments show that miR-126 regulates myeloid vs. B-cell fate through an alternative machinery, establishing the critical role of miRNAs in the lineage specification of multipotent mammalian cells. PMID:23893300

  17. Disseminated prostate cancer cells can instruct hematopoietic stem and progenitor cells to regulate bone phenotype.

    PubMed

    Joseph, Jeena; Shiozawa, Yusuke; Jung, Younghun; Kim, Jin Koo; Pedersen, Elisabeth; Mishra, Anjali; Zalucha, Janet Linn; Wang, Jingcheng; Keller, Evan T; Pienta, Kenneth J; Taichman, Russell S

    2012-03-01

    Prostate cancer metastases and hematopoietic stem cells (HSC) frequently home to the bone marrow, where they compete to occupy the same HSC niche. We have also shown that under conditions of hematopoietic stress, HSCs secrete the bone morphogenetic proteins (BMP)-2 and BMP-6 that drives osteoblastic differentiation from mesenchymal precursors. As it is not known, we examined whether metastatic prostate cancer cells can alter regulation of normal bone formation by HSCs and hematopoietic progenitor cells (HPC). HSC/HPCs isolated from mice bearing nonmetastatic and metastatic tumor cells were isolated and their ability to influence osteoblastic and osteoclastic differentiation was evaluated. When the animals were inoculated with the LNCaP C4-2B cell line, which produces mixed osteoblastic and osteolytic lesions in bone, HPCs, but not HSCs, were able to induced stromal cells to differentiate down an osteoblastic phenotype. Part of the mechanism responsible for this activity was the production of BMP-2. On the other hand, when the animals were implanted with PC3 cells that exhibits predominantly osteolytic lesions in bone, HSCs derived from these animals were capable of directly differentiating into tartrate-resistant acid phosphatase-positive osteoclasts through an interleukin-6-mediated pathway. These studies for the first time identify HSC/HPCs as novel targets for future therapy involved in the bone abnormalities of prostate cancer. PMID:22241219

  18. Case Report: Myelodysplastic syndrome- associated myeloid sarcoma: an unusual clinical presentation of a rare disease.

    PubMed

    Horvath, Emoke; Demian, Smaranda; Nagy, Elod

    2016-01-01

    Myeloid sarcoma results from the extramedullary homing and proliferation of immature myeloid precursors. We present the timeline, events and diagnostic pitfalls related to a 66 year-old male patient's case, admitted to the Hematology Clinic for pancytopenia, fever, weight loss and fatigue. The severe cytopenia and the few blasts observed in his blood smear indicated a bone marrow biopsy. The bone marrow showed hypercellularity and multilineage dysplasia with the presence of 15% myeloblasts. After the biopsy, he promptly developed paraplegia and nuclear magnetic resonance revealed an epidural tumour which was then resected.In the epidural tumour mass blast-like, round cells were observed with a complex immunophenotype, characterized by myeloperoxidase, CD117, CD15, CD99, leucocyte common antigen positivity and a high Ki-67 proliferation index. Considering the main differential diagnostic issues, the final diagnosis was stated as myelodysplastic syndrome-associated myeloid sarcoma. The prognosis was unfavourable, the bone marrow was quickly invaded by proliferating blast cells, and despite chemotherapy attempts, the patient died. PMID:27019694

  19. Case Report: Myelodysplastic syndrome- associated myeloid sarcoma: an unusual clinical presentation of a rare disease

    PubMed Central

    Horvath, Emoke; Demian, Smaranda; Nagy, Elod

    2016-01-01

    Myeloid sarcoma results from the extramedullary homing and proliferation of immature myeloid precursors. We present the timeline, events and diagnostic pitfalls related to a 66 year-old male patient’s case, admitted to the Hematology Clinic for pancytopenia, fever, weight loss and fatigue. The severe cytopenia and the few blasts observed in his blood smear indicated a bone marrow biopsy. The bone marrow showed hypercellularity and multilineage dysplasia with the presence of 15% myeloblasts. After the biopsy, he promptly developed paraplegia and nuclear magnetic resonance revealed an epidural tumour which was then resected.In the epidural tumour mass blast-like, round cells were observed with a complex immunophenotype, characterized by myeloperoxidase, CD117, CD15, CD99, leucocyte common antigen positivity and a high Ki-67 proliferation index. Considering the main differential diagnostic issues, the final diagnosis was stated as myelodysplastic syndrome-associated myeloid sarcoma. The prognosis was unfavourable, the bone marrow was quickly invaded by proliferating blast cells, and despite chemotherapy attempts, the patient died. PMID:27019694

  20. Myeloid-derived suppressor cells function as novel osteoclast progenitors enhancing bone loss in breast cancer

    PubMed Central

    Sawant, Anandi; Deshane, Jessy; Jules, Joel; Lee, Carnella M.; Harris, Brittney A.; Feng, Xu; Ponnazhagan, Selvarangan

    2012-01-01

    Enhanced bone destruction is a hallmark of various carcinomas such as breast cancer, where osteolytic bone metastasis is associated with increased morbidity and mortality. Immune cells contribute to osteolysis in cancer growth but the factors contributing to aggressive bone destruction are not well understood. In this study, we demonstrate the importance of myeloid-derived suppressor cells (MDSC) in this process at bone metastatic sites. Since MDSC originate from the same myeloid lineage as macrophages, which are osteoclast precursors, we hypothesized that MDSC may undergo osteoclast differentiation and contribute to enhanced bone destruction and tumor growth. Using an immunocompetent mouse model of breast cancer bone metastasis, we confirmed that MDSC isolated from the tumor-bone microenvironment differentiated into functional osteoclasts both in vitro and in vivo. Mechanistic investigations revealed that nitric oxide signaling was critical for differentiation of MDSC into osteoclasts. Remarkably, osteoclast differentiation did not occur in MDSC isolated from control or tumor-bearing mice that lacked bone metastasis, signifying the essential cross-talk between tumor cells and myeloid progenitors in the bone microenvironment as a requirement for osteoclast differentiation of MDSC. Overall, our results identify a wholly new facet to the multifunctionality of MDSC in driving tumor progression, in this case as a novel osteoclast progenitor that specifically drives bone metastasis during cancer progression. PMID:23243021

  1. OXIDANT-PRECURSOR RELATIONSHIPS

    EPA Science Inventory

    New methods of ambient air analysis were used to define more clearly the relationships between oxidants and their precursors. Non-methane hydrocarbons, NOx, O2, and oxidants were measured at the same time and location (Riverside, California). The ambient air data presented in thi...

  2. Untangling ENSO Precursors

    NASA Astrophysics Data System (ADS)

    Pegion, K.; Alexander, M. A.

    2014-12-01

    There are several proposed precursors to the El Nino-Southern Oscillation (ENSO) that may provide the ability to predict ENSO as much as one year in advance. Some of these precursors are associated with stochastic forcing from extratropical atmospheric variability. Two examples are the seasonal footprinting mechanism (SFM) and the Pacific meridional mode (PMM). Both of these ENSO precursors are thought to be forced by the North Pacific Oscillation (NPO), a north-south sea level pressure dipole in the north Pacific. Additionally, both the PMM and SFM are thought to impact the tropics through wind evaporation SST feedbacks and have a correlation with ENSO up to one year in advance. These two precursors are discussed interchangeably throughout the literature and various indices used to define them co-mingle them. As a result, whether they are independent of each other or are part of the same process has not been investigated. The research presented is focused on untangling the relationship between the PMM, SFM, NPO, and ENSO using observational datasets and model simulations. Observational results demonstrate that these two mechanisms are different, are forced by different atmospheric circulations, and result in different manifestations of ENSO. Modeling results highlight the extent to which climate models can simulate these relationships and their impact on the simulation of ENSO.

  3. Acute Myeloid Leukemia: A Concise Review

    PubMed Central

    Saultz, Jennifer N.; Garzon, Ramiro

    2016-01-01

    Acute myeloid leukemia (AML) is a heterogeneous clonal disorder characterized by immature myeloid cell proliferation and bone marrow failure. Cytogenetics and mutation testing remain a critical prognostic tool for post induction treatment. Despite rapid advances in the field including new drug targets and increased understanding of the biology, AML treatment remains unchanged for the past three decades with the majority of patients eventually relapsing and dying of the disease. Allogenic transplant remains the best chance for cure for patients with intermediate or high risk disease. In this review, we discuss the landmark genetic studies that have improved outcome prediction and novel therapies. PMID:26959069

  4. Contrasting Roles for C/EBPα and Notch in Irradiation-Induced Multipotent Hematopoietic Progenitor Cell Defects

    PubMed Central

    Fleenor, Courtney Jo; Rozhok, Andrii Ivan; Zaberezhnyy, Vadym; Mathew, Divij; Kim, Jihye; Tan, Aik-Choon; Bernstein, Irwin David; DeGregori, James

    2014-01-01

    Ionizing radiation (IR) is associated with reduced hematopoietic function and increased risk of hematopoietic malignancies, although the mechanisms behind these relationships remain poorly understood. Both effects of IR have been commonly attributed to the direct induction of DNA mutations, but evidence supporting these hypotheses is largely lacking. Here we demonstrate that IR causes long-term, somatically heritable, cell-intrinsic reductions in hematopoietic stem cell (HSC) and multipotent hematopoietic progenitor cell (mHPC) self-renewal that are mediated by C/EBPα and reversed by Notch. mHPC from previously irradiated (>9 weeks prior), homeostatically restored mice exhibit gene expression profiles consistent with their precocious differentiation phenotype, including decreased expression of HSC-specific genes and increased expression of myeloid program genes (including C/EBPα). These gene expression changes are reversed by ligand-mediated activation of Notch. Loss of C/EBPα expression is selected for within previously irradiated HSC and mHPC pools, and is associated with reversal of IR-dependent precocious differentiation and restoration of self-renewal. Remarkably, restoration of mHPC self-renewal by ligand-mediated activation of Notch prevents selection for C/EBPα loss of function in previously irradiated mHPC pools. We propose that environmental insults prompt HSC to initiate a program limiting their self-renewal, leading to loss of the damaged HSC from the pool while allowing this HSC to temporarily contribute to differentiated cell pools. This “programmed mediocrity” is advantageous for the sporadic genotoxic insults animals have evolved to deal with, but becomes tumor promoting when the entire HSC compartment is damaged, such as during total body irradiation, by increasing selective pressure for adaptive oncogenic mutations. PMID:25546133

  5. Contrasting roles for C/EBPα and Notch in irradiation-induced multipotent hematopoietic progenitor cell defects.

    PubMed

    Fleenor, Courtney Jo; Rozhok, Andrii Ivan; Zaberezhnyy, Vadym; Mathew, Divij; Kim, Jihye; Tan, Aik-Choon; Bernstein, Irwin David; DeGregori, James

    2015-04-01

    Ionizing radiation (IR) is associated with reduced hematopoietic function and increased risk of hematopoietic malignancies, although the mechanisms behind these relationships remain poorly understood. Both effects of IR have been commonly attributed to the direct induction of DNA mutations, but evidence supporting these hypotheses is largely lacking. Here we demonstrate that IR causes long-term, somatically heritable, cell-intrinsic reductions in hematopoietic stem cell (HSC) and multipotent hematopoietic progenitor cell (mHPC) self-renewal that are mediated by C/EBPα and reversed by Notch. mHPC from previously irradiated (>9 weeks prior), homeostatically restored mice exhibit gene expression profiles consistent with their precocious differentiation phenotype, including decreased expression of HSC-specific genes and increased expression of myeloid program genes (including C/EBPα). These gene expression changes are reversed by ligand-mediated activation of Notch. Loss of C/EBPα expression is selected for within previously irradiated HSC and mHPC pools and is associated with reversal of IR-dependent precocious differentiation and restoration of self-renewal. Remarkably, restoration of mHPC self-renewal by ligand-mediated activation of Notch prevents selection for C/EBPα loss of function in previously irradiated mHPC pools. We propose that environmental insults prompt HSC to initiate a program limiting their self-renewal, leading to loss of the damaged HSC from the pool while allowing this HSC to temporarily contribute to differentiated cell pools. This "programmed mediocrity" is advantageous for the sporadic genotoxic insults animals have evolved to deal with but becomes tumor promoting when the entire HSC compartment is damaged, such as during total body irradiation, by increasing selective pressure for adaptive oncogenic mutations. PMID:25546133

  6. Vaccine Therapy and Basiliximab in Treating Patients With Acute Myeloid Leukemia in Complete Remission

    ClinicalTrials.gov

    2016-06-27

    Adult Acute Myeloid Leukemia in Remission; Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22)

  7. CPI-613, Cytarabine, and Mitoxantrone Hydrochloride in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia

    ClinicalTrials.gov

    2015-06-23

    Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Recurrent Adult Acute Myeloid Leukemia

  8. Lenalidomide and Cytarabine in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia

    ClinicalTrials.gov

    2016-04-01

    Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Recurrent Adult Acute Myeloid Leukemia

  9. Decitabine With or Without Bortezomib in Treating Older Patients With Acute Myeloid Leukemia

    ClinicalTrials.gov

    2016-03-14

    Acute Myeloid Leukemia Arising From Previous Myelodysplastic Syndrome; Adult Acute Megakaryoblastic Leukemia; Adult Acute Monoblastic Leukemia; Adult Acute Monocytic Leukemia; Adult Acute Myeloid Leukemia With Minimal Differentiation; Adult Acute Myeloid Leukemia With t(9;11)(p22;q23); MLLT3-MLL; Adult Acute Myeloid Leukemia Without Maturation; Adult Erythroleukemia; Adult Pure Erythroid Leukemia; Alkylating Agent-Related Acute Myeloid Leukemia; Secondary Acute Myeloid Leukemia; Untreated Adult Acute Myeloid Leukemia

  10. Daunorubicin Hydrochloride, Cytarabine and Oblimersen Sodium in Treating Patients With Previously Untreated Acute Myeloid Leukemia

    ClinicalTrials.gov

    2013-06-04

    Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Secondary Acute Myeloid Leukemia; Untreated Adult Acute Myeloid Leukemia

  11. Clofarabine and Cytarabine in Treating Patients With Acute Myeloid Leukemia With Minimal Residual Disease

    ClinicalTrials.gov

    2013-05-07

    Adult Acute Myeloid Leukemia in Remission; Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Recurrent Adult Acute Myeloid Leukemia

  12. Clofarabine, Cytarabine, and G-CSF in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia

    ClinicalTrials.gov

    2015-05-05

    Acute Myeloid Leukemia; Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Adult Acute Promyelocytic Leukemia (M3); Recurrent Adult Acute Myeloid Leukemia

  13. Supportive Care of Hematopoietic Cell Transplant Patients

    PubMed Central

    Jim, Heather S. L.; Syrjala, Karen L.; Rizzo, Doug

    2012-01-01

    Hematopoietic cell transplant survivors face a number of challenges including low energy and stamina, “chemo-brain” and emotional distress, and late effects that can compromise functioning or lead to early mortality. This session will review the most recent interventions and recommendations to avoid or mitigate these complications. PMID:22226095

  14. Hematopoiesis and hematopoietic organs in arthropods.

    PubMed

    Grigorian, Melina; Hartenstein, Volker

    2013-03-01

    Hemocytes (blood cells) are motile cells that move throughout the extracellular space and that exist in all clades of the animal kingdom. Hemocytes play an important role in shaping the extracellular environment and in the immune response. Developmentally, hemocytes are closely related to the epithelial cells lining the vascular system (endothelia) and the body cavity (mesothelia). In vertebrates and insects, common progenitors, called hemangioblasts, give rise to the endothelia and blood cells. In the adult animal, many differentiated hemocytes seem to retain the ability to proliferate; however, in most cases investigated closely, the bulk of hemocyte proliferation takes place in specialized hematopoietic organs. Hematopoietic organs provide an environment where undifferentiated blood stem cells are able to self-renew, and at the same time generate offspring that differentiate into different blood cell types. Hematopoiesis in vertebrates, taking place in the bone marrow, has been subject to intensive research by immunologists and stem cell biologists. Much less is known about blood cell formation in invertebrate animals. In this review, we will survey structural and functional properties of invertebrate hematopoietic organs, with a main focus on insects and other arthropod taxa. We will then discuss similarities, at the molecular and structural level, that are apparent when comparing the development of blood cells in hematopoietic organs of vertebrates and arthropods. Our comparative review is intended to elucidate aspects of the biology of blood stem cells that are more easily missed when focusing on one or a few model species. PMID:23319182

  15. Hematopoiesis and Hematopoietic Organs in Arthropods

    PubMed Central

    Grigorian, Melina; Hartenstein, Volker

    2013-01-01

    Hemocytes (blood cells) are motile cells moving throughout the extracellular space and exist in all clades of the animal kingdom. Hemocytes play an important role in shaping the extracellular environment and in the immune response. Developmentally, hemocytes are closely related to the epithelial cells lining the vascular system (endothelia) and body cavity (mesothelia). In vertebrates and insects, common progenitors, called hemangioblasts, give rise to the endothelia and blood cells. In the adult animal, many differentiated hemocytes seem to retain the ability to proliferate; however, in most cases investigated closely, the bulk of hemocyte proliferation takes place in specialized hematopoietic organs. Hematopoietic organs provide an environment where undifferentiated blood stem cells are able to self renew, and at the same time generate offspring that differentiate into different blood cell types. Hematopoiesis in vertebrates, taking place in the bone marrow, has been subject to intensive research by immunologists and stem cell biologists. Much less is known about blood cell formation in invertebrate animals. In this review we will survey structural and functional properties of invertebrate hematopoietic organs, with a main focus on insects and other arthropod taxa. We will then discuss similarities, at the molecular and structural level, that are apparent when comparing the development of blood cells in hematopoietic organs of vertebrates and arthropods. Our comparative review is intended to elucidate aspects of the biology of blood stem cells that are more easily missed when focusing on one or a few model species. PMID:23319182

  16. Lenalidomide in Treating Older Patients With Acute Myeloid Leukemia

    ClinicalTrials.gov

    2014-07-25

    Adult Acute Basophilic Leukemia; Adult Acute Eosinophilic Leukemia; Adult Acute Megakaryoblastic Leukemia (M7); Adult Acute Minimally Differentiated Myeloid Leukemia (M0); Adult Acute Monoblastic Leukemia (M5a); Adult Acute Monocytic Leukemia (M5b); Adult Acute Myeloblastic Leukemia With Maturation (M2); Adult Acute Myeloblastic Leukemia Without Maturation (M1); Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Adult Acute Myelomonocytic Leukemia (M4); Adult Erythroleukemia (M6a); Adult Pure Erythroid Leukemia (M6b); Secondary Acute Myeloid Leukemia; Untreated Adult Acute Myeloid Leukemia

  17. Hematopoietic stem cells develop in the absence of endothelial cadherin 5 expression.

    PubMed

    Anderson, Heidi; Patch, Taylor C; Reddy, Pavankumar N G; Hagedorn, Elliott J; Kim, Peter G; Soltis, Kathleen A; Chen, Michael J; Tamplin, Owen J; Frye, Maike; MacLean, Glenn A; Hübner, Kathleen; Bauer, Daniel E; Kanki, John P; Vogin, Guillaume; Huston, Nicholas C; Nguyen, Minh; Fujiwara, Yuko; Paw, Barry H; Vestweber, Dietmar; Zon, Leonard I; Orkin, Stuart H; Daley, George Q; Shah, Dhvanit I

    2015-12-24

    Rare endothelial cells in the aorta-gonad-mesonephros (AGM) transition into hematopoietic stem cells (HSCs) during embryonic development. Lineage tracing experiments indicate that HSCs emerge from cadherin 5 (Cdh5; vascular endothelial-cadherin)(+) endothelial precursors, and isolated populations of Cdh5(+) cells from mouse embryos and embryonic stem cells can be differentiated into hematopoietic cells. Cdh5 has also been widely implicated as a marker of AGM-derived hemogenic endothelial cells. Because Cdh5(-/-) mice embryos die before the first HSCs emerge, it is unknown whether Cdh5 has a direct role in HSC emergence. Our previous genetic screen yielded malbec (mlb(bw306)), a zebrafish mutant for cdh5, with normal embryonic and definitive blood. Using time-lapse confocal imaging, parabiotic surgical pairing of zebrafish embryos, and blastula transplantation assays, we show that HSCs emerge, migrate, engraft, and differentiate in the absence of cdh5 expression. By tracing Cdh5(-/-)green fluorescent protein (GFP)(+/+) cells in chimeric mice, we demonstrated that Cdh5(-/-)GFP(+/+) HSCs emerging from embryonic day 10.5 and 11.5 (E10.5 and E11.5) AGM or derived from E13.5 fetal liver not only differentiate into hematopoietic colonies but also engraft and reconstitute multilineage adult blood. We also developed a conditional mouse Cdh5 knockout (Cdh5(flox/flox):Scl-Cre-ER(T)) and demonstrated that multipotent hematopoietic colonies form despite the absence of Cdh5. These data establish that Cdh5, a marker of hemogenic endothelium in the AGM, is dispensable for the transition of hemogenic endothelium to HSCs. PMID:26385351

  18. Type I IFN drives emergency myelopoiesis and peripheral myeloid expansion during chronic Toll-like receptor 7 signaling1

    PubMed Central

    Buechler, Matthew B.; Teal, Thomas H.; Elkon, Keith B.; Hamerman, Jessica A.

    2012-01-01

    Mice overexpressing TLR7 (TLR7.1 mice) are a model of SLE pathogenesis and exhibit peripheral myeloid expansion. We show that TLR7.1 mice have a dramatic expansion of splenic cells that derive from granulocyte/macrophage progenitors (GMP) compared to WT mice. In the bone marrow, TLR7.1 mice exhibited hallmarks of emergency myelopoiesis and contained a discrete population of Sca-1+ GMP, termed emergency GMP (eGMP), that are more proliferative and superior myeloid precursors than classical Sca-1− GMP. The emergency myelopoiesis and peripheral myeloid expansion in TLR7.1 mice was dependent on type I IFN signaling. TLR7 agonist administration to non-transgenic mice also drove type I IFN-dependent emergency myelopoiesis. TLR7.1 plasmacytoid DC were cell-intrinsically activated by TLR7 overexpression and constitutively produced type I IFN directly ex vivo. This work shows that type I IFN can act upon myeloid progenitors to promote the development of eGMP, which leads to an expansion of their progeny in the periphery. PMID:23303674

  19. PECAM-1, apoptosis and CD34+ precursors.

    PubMed

    Zocchi, Maria R; Poggi, A

    2004-11-01

    Apoptosis is a physiological process that controls tissue homeostasis, in combination with survival signals delivered by distinct receptors that bind hormones, growth factors or extracellular matrix components. The extrinsic pathway of apoptosis is due to the triggering of death receptors and the activation of the caspase cascade; the intrinsic pathway is due to withdrawal of growth factors and mainly related to mitochondrial metabolism. The choice between survival or apoptosis, which is the result of such different integrated environmental signals, is crucial for the maintainance of bone marrow reservoir of hematopoietic precursors (HPC). CD34+ HPC can receive multiple survival signals during homing and maturation, due to different interactions with adhesion molecules expressed on endothelial and bone marrow stromal cells, proteins of the extracellular matrix and chemokines or growth factors. Among them, the signal delivered via platelet endothelial cell adhesion molecule-1 (PECAM-1) seems to contribute to the resistance of this cell population to starvation, and it is related to the maintainance of mitochondrial metabolism. Indeed, this molecule, originally described as an adhesion receptor belonging to the immunoglobulin superfamily, capable of homophilic and heterophilic interactions, turned out to be a signalling molecule, containing an immunoreceptor tyrosine-based inhibitory motifs (ITIM) within its cytoplasmic domain. In particular, it has been shown that PECAM-1 binds to different kinases and phosphatases, including the phosphatidylinositide-3-kinase that phosphorylates Akt, which, in turn can upregulate transcription and function of antiapoptotic proteins, such as Bcl-2 and Bcl-x or A1, responsible for the rescue from mitochondrial apoptosis. The possible role of PECAM-1 engagement in the prevention of starvation-induced apoptosis of HPC precursors and in the maintainance of their survival is discussed. PMID:15512808

  20. Genetic predisposition to pediatric myeloid malignancies.

    PubMed

    Muramatsu, Hideki

    2016-06-01

    Various genetic disorders are known to be associated with cancer predisposition. For example, children with Down syndrome are predisposed to developing acute myeloid leukemia, and those with RASopathies, such as Noonan syndrome, are predisposed to juvenile myelomonocytic leukemia. To date, more than 250 diseases or syndromes have been reported to be associated with the development of pediatric cancers. Recently, the advent of the massive parallel sequencing technique revealed several germline mutations, including RUNX1, CEBPA, GATA2, SRP72, ETV6, and DDX41, which are associated with familial myeloid malignancies. A significant number of children with myeloid malignancies may harbor pathognomonic germline variants. It is strongly recommended that precise diagnosis, genetic counseling, familial screening, and follow-up programs be provided for patients with such a predisposition to cancer. To identify genetic disorders associated with predispositions to pediatric myeloid malignancies, the development of an efficient screening system with the massive parallel sequencer for germline and somatic mutations, which would also be useful for familial genetic studies and prediction of tumor progression, is needed. PMID:27384852

  1. Myeloid Cells in Cutaneous Wound Repair.

    PubMed

    Cash, Jenna L; Martin, Paul

    2016-06-01

    Cutaneous wound repair is a complex, dynamic process with the goal of rapidly sealing any breach in the skin's protective barrier. Myeloid cells compose a significant proportion of the inflammatory cells recruited to a wound site and play important roles in decontaminating the injured tissue of any invading microorganisms. Subsequently, myeloid cells are able to influence many aspects of the healing response, in part through their capacity to release a large array of signaling molecules that allow them to communicate with and regulate the behavior of other wound cells and in turn, be themselves exquisitely regulated by the wound microenvironment. Macrophages, for example, appear to play important, temporally changing roles in the initiation of scarring and subsequently in matrix remodeling to resolve fibrosis. In this way, myeloid cells seem to play both positive (e.g., pathogen killing and matrix remodeling) and negative (e.g., scarring) roles in wound repair. Further research is of course needed to elucidate the precise temporal and spatial myeloid cell phenotypes and behaviors and ultimately to design effective strategies to optimize the beneficial functions of these cells while minimizing their detrimental contributions to improve wound healing in the clinic. PMID:27337466

  2. Chronic myeloid leukemia: reminiscences and dreams

    PubMed Central

    Mughal, Tariq I.; Radich, Jerald P.; Deininger, Michael W.; Apperley, Jane F.; Hughes, Timothy P.; Harrison, Christine J.; Gambacorti-Passerini, Carlo; Saglio, Giuseppe; Cortes, Jorge; Daley, George Q.

    2016-01-01

    With the deaths of Janet Rowley and John Goldman in December 2013, the world lost two pioneers in the field of chronic myeloid leukemia. In 1973, Janet Rowley, unraveled the cytogenetic anatomy of the Philadelphia chromosome, which subsequently led to the identification of the BCR-ABL1 fusion gene and its principal pathogenetic role in the development of chronic myeloid leukemia. This work was also of major importance to support the idea that cytogenetic changes were drivers of leukemogenesis. John Goldman originally made seminal contributions to the use of autologous and allogeneic stem cell transplantation from the late 1970s onwards. Then, in collaboration with Brian Druker, he led efforts to develop ABL1 tyrosine kinase inhibitors for the treatment of patients with chronic myeloid leukemia in the late 1990s. He also led the global efforts to develop and harmonize methodology for molecular monitoring, and was an indefatigable organizer of international conferences. These conferences brought together clinicians and scientists, and accelerated the adoption of new therapies. The abundance of praise, tributes and testimonies expressed by many serve to illustrate the indelible impressions these two passionate and affable scholars made on so many people’s lives. This tribute provides an outline of the remarkable story of chronic myeloid leukemia, and in writing it, it is clear that the historical triumph of biomedical science over this leukemia cannot be considered without appreciating the work of both Janet Rowley and John Goldman. PMID:27132280

  3. Chronic myeloid leukemia: reminiscences and dreams.

    PubMed

    Mughal, Tariq I; Radich, Jerald P; Deininger, Michael W; Apperley, Jane F; Hughes, Timothy P; Harrison, Christine J; Gambacorti-Passerini, Carlo; Saglio, Giuseppe; Cortes, Jorge; Daley, George Q

    2016-05-01

    With the deaths of Janet Rowley and John Goldman in December 2013, the world lost two pioneers in the field of chronic myeloid leukemia. In 1973, Janet Rowley, unraveled the cytogenetic anatomy of the Philadelphia chromosome, which subsequently led to the identification of the BCR-ABL1 fusion gene and its principal pathogenetic role in the development of chronic myeloid leukemia. This work was also of major importance to support the idea that cytogenetic changes were drivers of leukemogenesis. John Goldman originally made seminal contributions to the use of autologous and allogeneic stem cell transplantation from the late 1970s onwards. Then, in collaboration with Brian Druker, he led efforts to develop ABL1 tyrosine kinase inhibitors for the treatment of patients with chronic myeloid leukemia in the late 1990s. He also led the global efforts to develop and harmonize methodology for molecular monitoring, and was an indefatigable organizer of international conferences. These conferences brought together clinicians and scientists, and accelerated the adoption of new therapies. The abundance of praise, tributes and testimonies expressed by many serve to illustrate the indelible impressions these two passionate and affable scholars made on so many people's lives. This tribute provides an outline of the remarkable story of chronic myeloid leukemia, and in writing it, it is clear that the historical triumph of biomedical science over this leukemia cannot be considered without appreciating the work of both Janet Rowley and John Goldman. PMID:27132280

  4. BCOR regulates myeloid cell proliferation and differentiation.

    PubMed

    Cao, Q; Gearhart, M D; Gery, S; Shojaee, S; Yang, H; Sun, H; Lin, D-C; Bai, J-W; Mead, M; Zhao, Z; Chen, Q; Chien, W-W; Alkan, S; Alpermann, T; Haferlach, T; Müschen, M; Bardwell, V J; Koeffler, H P

    2016-05-01

    BCOR is a component of a variant Polycomb group repressive complex 1 (PRC1). Recently, we and others reported recurrent somatic BCOR loss-of-function mutations in myelodysplastic syndrome and acute myelogenous leukemia (AML). However, the role of BCOR in normal hematopoiesis is largely unknown. Here, we explored the function of BCOR in myeloid cells using myeloid murine models with Bcor conditional loss-of-function or overexpression alleles. Bcor mutant bone marrow cells showed significantly higher proliferation and differentiation rates with upregulated expression of Hox genes. Mutation of Bcor reduced protein levels of RING1B, an H2A ubiquitin ligase subunit of PRC1 family complexes and reduced H2AK119ub upstream of upregulated HoxA genes. Global RNA expression profiling in murine cells and AML patient samples with BCOR loss-of-function mutation suggested that loss of BCOR expression is associated with enhanced cell proliferation and myeloid differentiation. Our results strongly suggest that BCOR plays an indispensable role in hematopoiesis by inhibiting myeloid cell proliferation and differentiation and offer a mechanistic explanation for how BCOR regulates gene expression such as Hox genes. PMID:26847029

  5. Azacitidine, Mitoxantrone Hydrochloride, and Etoposide in Treating Older Patients With Poor-Prognosis Acute Myeloid Leukemia

    ClinicalTrials.gov

    2015-08-18

    Acute Myeloid Leukemia Arising From Previous Myelodysplastic Syndrome; Adult Acute Basophilic Leukemia; Adult Acute Eosinophilic Leukemia; Adult Acute Megakaryoblastic Leukemia; Adult Acute Monoblastic Leukemia; Adult Acute Monocytic Leukemia; Adult Acute Myeloid Leukemia in Remission; Adult Acute Myeloid Leukemia With Inv(16)(p13.1q22); CBFB-MYH11; Adult Acute Myeloid Leukemia With Maturation; Adult Acute Myeloid Leukemia With Minimal Differentiation; Adult Acute Myeloid Leukemia With t(16;16)(p13.1;q22); CBFB-MYH11; Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); RUNX1-RUNX1T1; Adult Acute Myeloid Leukemia With t(9;11)(p22;q23); MLLT3-MLL; Adult Acute Myeloid Leukemia Without Maturation; Adult Acute Myelomonocytic Leukemia; Adult Erythroleukemia; Adult Pure Erythroid Leukemia; Alkylating Agent-Related Acute Myeloid Leukemia; Recurrent Adult Acute Myeloid Leukemia; Secondary Acute Myeloid Leukemia; Untreated Adult Acute Myeloid Leukemia

  6. Decitabine in Treating Patients With Myelodysplastic Syndromes or Acute Myeloid Leukemia

    ClinicalTrials.gov

    2013-09-27

    Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Atypical Chronic Myeloid Leukemia, BCR-ABL1 Negative; de Novo Myelodysplastic Syndromes; Myelodysplastic/Myeloproliferative Neoplasm, Unclassifiable; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Myeloid Leukemia; Secondary Acute Myeloid Leukemia; Secondary Myelodysplastic Syndromes; Untreated Adult Acute Myeloid Leukemia

  7. Removal of myeloid cytokines from the cellular environment enhances T-cell development in vitro.

    PubMed

    Smeets, Monique F M A; Mackenzie-Kludas, Charley; Mohtashami, Mahmood; Zhang, Hui-Hua; Zúñiga-Pflücker, Juan Carlos; Izon, David J

    2013-10-01

    The majority of T-cell development occurs in the thymus. Thymic epithelial cells are specialized cells that express NOTCH ligands and secrete specific cytokines required for normal T-cell lymphopoiesis. It has been demonstrated that OP9 cells derived from macrophage colony-stimulating factor (M-CSF)-deficient mice can support T-cell development when transduced with a NOTCH ligand, Delta-like 1 (Dll1). In this report, we have tested CSF-deficient mouse fibroblasts transduced with Dll1 for their ability to support T-cell differentiation. The data provided here demonstrate that CSF-deficient fibroblasts expressing DLL1 can support T-cell development. Indeed, co-cultures with these fibroblasts produced more T-cell progenitors compared with OP9-DL1 cultures. Addition of myeloid cytokines to OP9-DL1 co-cultures significantly inhibited T-cell development while CSF-deficient DLL1(+) fibroblasts retained partial T-cell differentiation. Taken together, these data imply that their lack of myeloid cytokines allows DLL1(+) fibroblasts to more efficiently generate T-cells. Development of this fibroblast system suggests that there is potential for generating human T-cell precursors via co-culture with human fibroblasts expressing DLL1 or DLL4. These T-cell precursors could be used for treating immunodeficient patients. PMID:23988615

  8. Hematopoietic Acute Radiation Syndrome (Bone marrow syndrome, Aplastic Anemia): Molecular Mechanisms of Radiation Toxicity.

    NASA Astrophysics Data System (ADS)

    Popov, Dmitri

    Key Words: Aplastic Anemia (AA), Pluripotential Stem Cells (PSC) Introduction: Aplastic Anemia (AA) is a disorder of the pluripotential stem cells involve a decrease in the number of cells of myeloid, erythroid and megakaryotic lineage [Segel et al. 2000 ]. The etiology of AA include idiopathic cases and secondary aplastic anemia after exposure to drugs, toxins, chemicals, viral infections, lympho-proliferative diseases, radiation, genetic causes, myelodisplastic syndromes and hypoplastic anemias, thymomas, lymphomas. [Brodskyet al. 2005.,Modan et al. 1975., Szklo et al. 1975]. Hematopoietic Acute Radiation Syndrome (or Bone marrow syndrome, or Radiation-Acquired Aplastic Anemia) is the acute toxic syndrome which usually occurs with a dose of irradiation between 0.7 and 10 Gy (70- 1000 rads), depending on the species irradiated. [Waselenko et al., 2004]. The etiology of bone morrow damage from high-level radiation exposure results depends on the radiosensitivity of certain bone marrow cell lines. [Waselenko et al. 2004] Aplastic anemia after radiation exposure is a clinical syndrome that results from a marked disorder of bone marrow blood cell production. [Waselenko et al. 2004] Radiation hematotoxicity is mediated via genotoxic and other specific toxic mechanisms, leading to aplasia, cell apoptosis or necrosis, initiation via genetic mechanisms of clonal disorders, in cases such as the acute radiation-acquired form of AA. AA results from radiation injury to pluripotential and multipotential stem cells in the bone marrow. The clinical signs displayed in reticulocytopenia, anemia, granulocytopenia, monocytopenia, and thrombocytopenia. The number of marrow CD34+ cells (multipotential hematopoietic progenitors) and their derivative colony-forming unit{granulocyte-macrophage (CFU-GM) and burst forming unit {erythroid (BFU{E) are reduced markedly in patients with AA. [Guinan 2011, Brodski et al. 2005, Beutler et al.,2000] Cells expressing CD34 (CD34+ cell) are normally

  9. The EM Earthquake Precursor

    NASA Astrophysics Data System (ADS)

    Jones, K. B., II; Saxton, P. T.

    2013-12-01

    Many attempts have been made to determine a sound forecasting method regarding earthquakes and warn the public in turn. Presently, the animal kingdom leads the precursor list alluding to a transmission related source. By applying the animal-based model to an electromagnetic (EM) wave model, various hypotheses were formed, but the most interesting one required the use of a magnetometer with a differing design and geometry. To date, numerous, high-end magnetometers have been in use in close proximity to fault zones for potential earthquake forecasting; however, something is still amiss. The problem still resides with what exactly is forecastable and the investigating direction of EM. After the 1989 Loma Prieta Earthquake, American earthquake investigators predetermined magnetometer use and a minimum earthquake magnitude necessary for EM detection. This action was set in motion, due to the extensive damage incurred and public outrage concerning earthquake forecasting; however, the magnetometers employed, grounded or buried, are completely subject to static and electric fields and have yet to correlate to an identifiable precursor. Secondly, there is neither a networked array for finding any epicentral locations, nor have there been any attempts to find even one. This methodology needs dismissal, because it is overly complicated, subject to continuous change, and provides no response time. As for the minimum magnitude threshold, which was set at M5, this is simply higher than what modern technological advances have gained. Detection can now be achieved at approximately M1, which greatly improves forecasting chances. A propagating precursor has now been detected in both the field and laboratory. Field antenna testing conducted outside the NE Texas town of Timpson in February, 2013, detected three strong EM sources along with numerous weaker signals. The antenna had mobility, and observations were noted for recurrence, duration, and frequency response. Next, two

  10. DNMT3A Arg882 mutation drives chronic myelomonocytic leukemia through disturbing gene expression/DNA methylation in hematopoietic cells

    PubMed Central

    Xu, Jie; Wang, Yue-Ying; Dai, Yu-Jun; Zhang, Wu; Zhang, Wei-Na; Xiong, Shu-Min; Gu, Zhao-Hui; Wang, Kan-Kan; Zeng, Rong; Chen, Zhu; Chen, Sai-Juan

    2014-01-01

    The gene encoding DNA methyltransferase 3A (DNMT3A) is mutated in ∼20% of acute myeloid leukemia cases, with Arg882 (R882) as the hotspot. Here, we addressed the transformation ability of the DNMT3A-Arg882His (R882H) mutant by using a retroviral transduction and bone marrow transplantation (BMT) approach and found that the mutant gene can induce aberrant proliferation of hematopoietic stem/progenitor cells. At 12 mo post-BMT, all mice developed chronic myelomonocytic leukemia with thrombocytosis. RNA microarray analysis revealed abnormal expressions of some hematopoiesis-related genes, and the DNA methylation assay identified corresponding changes in methylation patterns in gene body regions. Moreover, DNMT3A-R882H increased the CDK1 protein level and enhanced cell-cycle activity, thereby contributing to leukemogenesis. PMID:24497509

  11. A humanized bone marrow ossicle xenotransplantation model enables improved engraftment of healthy and leukemic human hematopoietic cells.

    PubMed

    Reinisch, Andreas; Thomas, Daniel; Corces, M Ryan; Zhang, Xiaohua; Gratzinger, Dita; Hong, Wan-Jen; Schallmoser, Katharina; Strunk, Dirk; Majeti, Ravindra

    2016-07-01

    Xenotransplantation models represent powerful tools for the investigation of healthy and malignant human hematopoiesis. However, current models do not fully mimic the components of the human bone marrow (BM) microenvironment, and they enable only limited engraftment of samples from some human malignancies. Here we show that a xenotransplantation model bearing subcutaneous humanized ossicles with an accessible BM microenvironment, formed by in situ differentiation of human BM-derived mesenchymal stromal cells, enables the robust engraftment of healthy human hematopoietic stem and progenitor cells, as well as primary acute myeloid leukemia (AML) samples, at levels much greater than those in unmanipulated mice. Direct intraossicle transplantation accelerated engraftment and resulted in the detection of substantially higher leukemia-initiating cell (LIC) frequencies. We also observed robust engraftment of acute promyelocytic leukemia (APL) and myelofibrosis (MF) samples, and identified LICs in these malignancies. This humanized ossicle xenotransplantation approach provides a system for modeling a wide variety of human hematological diseases. PMID:27213817

  12. miR-126 Regulates Distinct Self-Renewal Outcomes in Normal and Malignant Hematopoietic Stem Cells.

    PubMed

    Lechman, Eric R; Gentner, Bernhard; Ng, Stanley W K; Schoof, Erwin M; van Galen, Peter; Kennedy, James A; Nucera, Silvia; Ciceri, Fabio; Kaufmann, Kerstin B; Takayama, Naoya; Dobson, Stephanie M; Trotman-Grant, Aaron; Krivdova, Gabriela; Elzinga, Janneke; Mitchell, Amanda; Nilsson, Björn; Hermans, Karin G; Eppert, Kolja; Marke, Rene; Isserlin, Ruth; Voisin, Veronique; Bader, Gary D; Zandstra, Peter W; Golub, Todd R; Ebert, Benjamin L; Lu, Jun; Minden, Mark; Wang, Jean C Y; Naldini, Luigi; Dick, John E

    2016-02-01

    To investigate miRNA function in human acute myeloid leukemia (AML) stem cells (LSC), we generated a prognostic LSC-associated miRNA signature derived from functionally validated subpopulations of AML samples. For one signature miRNA, miR-126, high bioactivity aggregated all in vivo patient sample LSC activity into a single sorted population, tightly coupling miR-126 expression to LSC function. Through functional studies, miR-126 was found to restrain cell cycle progression, prevent differentiation, and increase self-renewal of primary LSC in vivo. Compared with prior results showing miR-126 regulation of normal hematopoietic stem cell (HSC) cycling, these functional stem effects are opposite between LSC and HSC. Combined transcriptome and proteome analysis demonstrates that miR-126 targets the PI3K/AKT/MTOR signaling pathway, preserving LSC quiescence and promoting chemotherapy resistance. PMID:26832662

  13. miR-126 Regulates Distinct Self-Renewal Outcomes in Normal and Malignant Hematopoietic Stem Cells

    PubMed Central

    Lechman, Eric R.; Gentner, Bernhard; Ng, Stanley W.K.; Schoof, Erwin M.; van Galen, Peter; Kennedy, James A.; Nucera, Silvia; Ciceri, Fabio; Kaufmann, Kerstin B.; Takayama, Naoya; Dobson, Stephanie M.; Trotman-Grant, Aaron; Krivdova, Gabriela; Elzinga, Janneke; Mitchell, Amanda; Nilsson, Björn; Hermans, Karin G.; Eppert, Kolja; Marke, Rene; Isserlin, Ruth; Voisin, Veronique; Bader, Gary D.; Zandstra, Peter W.; Golub, Todd R.; Ebert, Benjamin L.; Lu, Jun; Minden, Mark; Wang, Jean C.Y.; Naldini, Luigi; Dick, John E.

    2016-01-01

    Summary To investigate miRNA function in human acute myeloid leukemia (AML) stem cells (LSC), we generated a prognostic LSC-associated miRNA signature derived from functionally validated subpopulations of AML samples. For one signature miRNA, miR-126, high bioactivity aggregated all in vivo patient sample LSC activity into a single sorted population, tightly coupling miR-126 expression to LSC function. Through functional studies, miR-126 was found to restrain cell cycle progression, prevent differentiation, and increase self-renewal of primary LSC in vivo. Compared with prior results showing miR-126 regulation of normal hematopoietic stem cell (HSC) cycling, these functional stem effects are opposite between LSC and HSC. Combined transcriptome and proteome analysis demonstrates that miR-126 targets the PI3K/AKT/MTOR signaling pathway, preserving LSC quiescence and promoting chemotherapy resistance. PMID:26832662

  14. JNK1 in hematopoietically derived cells contributes to diet-induced inflammation and insulin resistance without affecting obesity.

    PubMed

    Solinas, Giovanni; Vilcu, Cristian; Neels, Jaap G; Bandyopadhyay, Gautam K; Luo, Jun-Li; Naugler, Willscott; Grivennikov, Sergei; Wynshaw-Boris, Anthony; Scadeng, Miriam; Olefsky, Jerrold M; Karin, Michael

    2007-11-01

    Obesity-induced insulin resistance is a major factor in the etiology of type 2 diabetes, and Jun kinases (JNKs) are key negative regulators of insulin sensitivity in the obese state. Activation of JNKs (mainly JNK1) in insulin target cells results in phosphorylation of insulin receptor substrates (IRSs) at serine and threonine residues that inhibit insulin signaling. JNK1 activation is also required for accumulation of visceral fat. Here we used reciprocal adoptive transfer experiments to determine whether JNK1 in myeloid cells, such as macrophages, also contributes to insulin resistance and central adiposity. Our results show that deletion of Jnk1 in the nonhematopoietic compartment protects mice from high-fat diet (HFD)-induced insulin resistance, in part through decreased adiposity. By contrast, Jnk1 removal from hematopoietic cells has no effect on adiposity but confers protection against HFD-induced insulin resistance by decreasing obesity-induced inflammation. PMID:17983584

  15. HIF prolyl hydroxylase 2 (PHD2) is a critical regulator of hematopoietic stem cell maintenance during steady-state and stress.

    PubMed

    Singh, Rashim Pal; Franke, Kristin; Kalucka, Joanna; Mamlouk, Soulafa; Muschter, Antje; Gembarska, Agnieszka; Grinenko, Tatyana; Willam, Carsten; Naumann, Ronald; Anastassiadis, Konstantinos; Stewart, A Francis; Bornstein, Stefan; Chavakis, Triantafyllos; Breier, Georg; Waskow, Claudia; Wielockx, Ben

    2013-06-27

    Hypoxia is a prominent feature in the maintenance of hematopoietic stem cell (HSC) quiescence and multipotency. Hypoxia-inducible factor (HIF) prolyl hydroxylase domain proteins (PHDs) serve as oxygen sensors and may therefore regulate this system. Here, we describe a mouse line with conditional loss of HIF prolyl hydroxylase 2 (PHD2) in very early hematopoietic precursors that results in self-renewal of multipotent progenitors under steady-state conditions in a HIF1α- and SMAD7-dependent manner. Competitive bone marrow (BM) transplantations show decreased peripheral and central chimerism of PHD2-deficient cells but not of the most primitive progenitors. Conversely, in whole BM transfer, PHD2-deficient HSCs replenish the entire hematopoietic system and display an enhanced self-renewal capacity reliant on HIF1α. Taken together, our results demonstrate that loss of PHD2 controls the maintenance of the HSC compartment under physiological conditions and causes the outcompetition of PHD2-deficient hematopoietic cells by their wild-type counterparts during stress while promoting the self-renewal of very early hematopoietic progenitors. PMID:23667053

  16. CD45 Phosphatase Inhibits STAT3 Transcription Factor Activity in Myeloid Cells and Promotes Tumor-Associated Macrophage Differentiation.

    PubMed

    Kumar, Vinit; Cheng, Pingyan; Condamine, Thomas; Mony, Sridevi; Languino, Lucia R; McCaffrey, Judith C; Hockstein, Neil; Guarino, Michael; Masters, Gregory; Penman, Emily; Denstman, Fred; Xu, Xiaowei; Altieri, Dario C; Du, Hong; Yan, Cong; Gabrilovich, Dmitry I

    2016-02-16

    Recruitment of monocytic myeloid-derived suppressor cells (MDSCs) and differentiation of tumor-associated macrophages (TAMs) are the major factors contributing to tumor progression and metastasis. We demonstrated that differentiation of TAMs in tumor site from monocytic precursors was controlled by downregulation of the activity of the transcription factor STAT3. Decreased STAT3 activity was caused by hypoxia and affected all myeloid cells but was not observed in tumor cells. Upregulation of CD45 tyrosine phosphatase activity in MDSCs exposed to hypoxia in tumor site was responsible for downregulation of STAT3. This effect was mediated by the disruption of CD45 protein dimerization regulated by sialic acid. Thus, STAT3 has a unique function in the tumor environment in controlling the differentiation of MDSC into TAM, and its regulatory pathway could be a potential target for therapy. PMID:26885857

  17. Immunoselection techniques in hematopoietic stem cell transplantation.

    PubMed

    Li Pira, Giuseppina; Biagini, Simone; Cicchetti, Elisabetta; Merli, Pietro; Brescia, Letizia Pomponia; Milano, Giuseppe Maria; Montanari, Mauro

    2016-06-01

    Hematopoietic Stem Cells Transplantation (HSCT) is an effective treatment for hematological and non-hematological diseases. The main challenge in autologous HSCT is purging of malignant cells to prevent relapse. In allogeneic HSCT graft-versus-host disease (GvHD) and opportunistic infections are frequent complications. Two types of graft manipulation have been introduced: the first one in the autologous context aimed at separating malignant cells from hematopoietic stem cells (HSC), and the second one in allogeneic HSCT aimed at reducing the incidence of GvHD and at accelerating immune reconstitution. Here we describe the manipulations used for cell purging in autologous HSCT or for T Cell Depletion (TCD) and T cell selection in allogeneic HSCT. More complex manipulations, requiring a Good Manufacturing Practice (GMP) facility, are briefly mentioned. PMID:27209628

  18. Hematopoietic stem cell engineering at a crossroads

    PubMed Central

    Rivière, Isabelle; Dunbar, Cynthia E.

    2012-01-01

    The genetic engineering of hematopoietic stem cells is the basis for potentially treating a large array of hereditary and acquired diseases, and stands as the paradigm for stem cell engineering in general. Recent clinical reports support the formidable promise of this approach but also highlight the limitations of the technologies used to date, which have on occasion resulted in clonal expansion, myelodysplasia, or leukemogenesis. New research directions, predicated on improved vector designs, targeted gene delivery or the therapeutic use of pluripotent stem cells, herald the advent of safer and more effective hematopoietic stem cell therapies that may transform medical practice. In this review, we place these recent advances in perspective, emphasizing the solutions emerging from a wave of new technologies and highlighting the challenges that lie ahead. PMID:22096239

  19. Exogenous endothelial cells as accelerators of hematopoietic reconstitution

    PubMed Central

    2012-01-01

    Despite the successes of recombinant hematopoietic-stimulatory factors at accelerating bone marrow reconstitution and shortening the neutropenic period post-transplantation, significant challenges remain such as cost, inability to reconstitute thrombocytic lineages, and lack of efficacy in conditions such as aplastic anemia. A possible means of accelerating hematopoietic reconstitution would be administration of cells capable of secreting hematopoietic growth factors. Advantages of this approach would include: a) ability to regulate secretion of cytokines based on biological need; b) long term, localized production of growth factors, alleviating need for systemic administration of factors that possess unintended adverse effects; and c) potential to actively repair the hematopoietic stem cell niche. Here we overview the field of hematopoietic growth factors, discuss previous experiences with mesenchymal stem cells (MSC) in accelerating hematopoiesis, and conclude by putting forth the rationale of utilizing exogenous endothelial cells as a novel cellular therapy for acceleration of hematopoietic recovery. PMID:23171397

  20. p62 is required to retain short-term repopulating and myeloid progenitor cells through inhibition of IKK/NF-κB/Ccl4 signaling at the bone marrow macrophage-osteoblast niche

    PubMed Central

    Chang, Kyung Hee; Sengupta, Amitava; Nayak, Ramesh C.; Duran, Angeles; Lee, Sang Jun; Pratt, Ronald G.; Wellendorf, Ashley M.; Hill, Sarah E.; Watkins, Marcus; Gonzalez-Nieto, Daniel; Aronow, Bruce J.; Starczynowski, Daniel T.; Civitelli, Roberto; Diaz-Meco, Maria T.; Moscat, Jorge; Cancelas, Jose A.

    2014-01-01

    In the bone marrow (BM), hematopoietic progenitors (HP) reside in specific anatomical niches near osteoblasts (Ob), macrophages (MΦ) and other cells forming the BM microenvironment. A connection between immunosurveillance and traffic of HP has been demonstrated but the regulatory signals that instruct immune regulation on HP circulation are unknown. We discovered that the BM microenvironment deficiency of p62, an autophagy regulator and signal organizer, results in loss of autophagic repression of macrophage contact-dependent activation of Ob NF-κB signaling. Consequently, Ob p62-deficient mice lose bone, Ob Ccl4 expression and HP chemotaxis towards Cxcl12 resulting in egress of short-term hematopoietic stem cells and myeloid progenitors. Finally, Ccl4 expression and myeloid progenitor egress are reversed by the deficiency of the p62 PB1 binding partner Nbr1. A functional ‘MΦ-Ob niche’ is required for myeloid progenitor/short-term stem cell retention, in which Ob p62 is required to maintain NF-κB signaling repression, osteogenesis and BM progenitor retention. PMID:25533346

  1. Vascular Precursor Cells

    PubMed Central

    Chaudhury, Hera; Goldie, Lauren C.

    2011-01-01

    Understanding the mechanisms that regulate the proliferation and differentiation of human stem and progenitor cells is critically important for the development and optimization of regenerative medicine strategies. For vascular regeneration studies, specifically, a true “vascular stem cell” population has not yet been identified. However, a number of cell types that exist endogenously, or can be generated or propagated ex vivo, function as vascular precursor cells and can participate in and/or promote vascular regeneration. Herein, we provide an overview of what is known about the regulation of their differentiation specifically toward a vascular endothelial cell phenotype. PMID:22866199

  2. Complex Variant of Philadelphia Translocation Involving Chromosomes 9, 12, and 22 in a Case with Chronic Myeloid Leukaemia

    PubMed Central

    Malvestiti, F.; Agrati, C.; Chinetti, S.; Di Meco, A.; Cirrincione, S.; Oggionni, M.; Grimi, B.; Maggi, F.; Simoni, G.; Grati, F. R.

    2014-01-01

    Chronic myeloid leukemia (CML) is a hematopoietic stem cell disorder included in the broader diagnostic category of myeloproliferative neoplasms, associated with fusion by BCR gene at chromosome 22q11 to ABL1 gene at chromosome 9q34 with the formation of the Philadelphia (Ph) chromosome. In 2–10% of CML cases, the fusion gene arises in connection with a variant translocation, involving chromosomes 9, 22, and one or more different chromosomes; consequently, the Ph chromosome could be masked within a complex chromosome rearrangement. In cases with variant Ph translocation a deletion on der(9) may be more frequently observed than in cases with the classical one. Herein we describe a novel case of CML with complex variant Ph translocation involving chromosomes 9, 12, and 22. We present the hematologic response and cytogenetic response after Imatinib treatment. We also speculated the mechanism which had originated the chromosome rearrangement. PMID:25045550

  3. On the potential role of DNMT1 in acute myeloid leukemia and myelodysplastic syndromes: not another mutated epigenetic driver.

    PubMed

    Benetatos, Leonidas; Vartholomatos, Georgios

    2016-10-01

    DNA methylation is the most common epigenetic modification in the mammalian genome. DNA methylation is governed by the DNA methyltransferases mainly DNMT1, DNMT3A, and DNMT3B. DNMT1 methylates hemimethylated DNA ensuring accurate DNA methylation maintenance. DNMT1 is involved in the proper differentiation of hematopoietic stem cells (HSCs) through the interaction with effector molecules. DNMT1 is deregulated in acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) as early as the leukemic stem cell stage. Through the interaction with fundamental transcription factors, non-coding RNAs, fusion oncogenes and by modulating core members of signaling pathways, it can affect leukemic cells biology. DNMT1 action might be also catalytic-independent highlighting a methylation-independent mode of action. In this review, we have gathered some current facts of DNMT1 role in AML and MDS and we also propose some perspectives for future studies. PMID:26983918

  4. Chronic variable stress activates hematopoietic stem cells

    PubMed Central

    Courties, Gabriel; Dutta, Partha; Iwamoto, Yoshiko; Zaltsman, Alex; von zur Muhlen, Constantin; Bode, Christoph; Fricchione, Gregory L.; Denninger, John; Lin, Charles P.; Vinegoni, Claudio; Libby, Peter; Swirski, Filip K.; Weissleder, Ralph; Nahrendorf, Matthias

    2014-01-01

    Exposure to psychosocial stress is a risk factor for many diseases, including atherosclerosis1,2. While incompletely understood, interaction between the psyche and the immune system provides one potential mechanism linking stress and disease inception and progression. Known crosstalk between the brain and immune system includes the hypothalamic–pituitary–adrenal axis, which centrally drives glucocorticoid production in the adrenal cortex, and the sympathetic–adrenal–medullary axis, which controls stress–induced catecholamine release in support of the fight–or–flight reflex3,4. It remains unknown however if chronic stress changes hematopoietic stem cell activity. Here we show that stress increases proliferation of these most primitive progenitors, giving rise to higher levels of disease–promoting inflammatory leukocytes. We found that chronic stress induced monocytosis and neutrophilia in humans. While investigating the source of leukocytosis in mice, we discovered that stress activates upstream hematopoietic stem cells. Sympathetic nerve fibers release surplus noradrenaline, which uses the β3 adrenergic receptor to signal bone marrow niche cells to decrease CXCL12 levels. Consequently, elevated hematopoietic stem cell proliferation increases output of neutrophils and inflammatory monocytes. When atherosclerosis–prone ApoE−/− mice encounter chronic stress, accelerated hematopoiesis promotes plaque features associated with vulnerable lesions that cause myocardial infarction and stroke in humans. PMID:24952646

  5. Genotoxic sensitivity of the developing hematopoietic system.

    PubMed

    Udroiu, Ion; Sgura, Antonella

    2016-01-01

    Genotoxic sensitivity seems to vary during ontogenetic development. Animal studies have shown that the spontaneous mutation rate is higher during pregnancy and infancy than in adulthood. Human and animal studies have found higher levels of DNA damage and mutations induced by mutagens in fetuses/newborns than in adults. This greater susceptibility could be due to reduced DNA repair capacity. In fact, several studies indicated that some DNA repair pathways seem to be deficient during ontogenesis. This has been demonstrated also in murine hematopoietic stem cells. Genotoxicity in the hematopoietic system has been widely studied for several reasons: it is easy to assess, deals with populations cycling also in the adults and may be relevant for leukemogenesis. Reviewing the literature concerning the application of the micronucleus test (a validated assay to assess genotoxicity) in fetus/newborns and adults, we found that the former show almost always higher values than the latter, both in animals treated with genotoxic substances and