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Sample records for leukemia virus-induced fusion

  1. Rabies Virus-Induced Membrane Fusion Pathway

    PubMed Central

    Gaudin, Yves

    2000-01-01

    Fusion of rabies virus with membranes is triggered at low pH and is mediated by the viral glycoprotein (G). The rabies virus-induced fusion pathway was studied by investigating the effects of exogenous lipids having various dynamic molecular shapes on the fusion process. Inverted cone-shaped lysophosphatidylcholines (LPCs) blocked fusion at a stage subsequent to fusion peptide insertion into the target membrane. Consistent with the stalk-hypothesis, LPC with shorter alkyl chains inhibited fusion at lower membrane concentrations and this inhibition was compensated by the presence of oleic acid. However, under suboptimal fusion conditions, short chain LPCs, which were translocated in the inner leaflet of the membranes, considerably reduced the lag time preceding membrane merging, resulting in faster kinetics of fusion. This indicated that the rate limiting step for fusion is the formation of a fusion pore in a diaphragm of restricted hemifusion. The previously described cold-stabilized prefusion complex was also characterized. This intermediate is at a well-advanced stage of the fusion process when the hemifusion diaphragm is destabilized, but lipid mixing is still restricted, probably by a ring-like complex of glycoproteins. I provide evidence that this state has a dynamic character and that its lipid organization can reverse back to two lipid bilayers. PMID:10931871

  2. Proteome analysis of sheep B lymphocytes in the course of bovine leukemia virus-induced leukemia.

    PubMed

    Reichert, Michal

    2017-07-01

    Presented are the results of a study of the expression pattern of different proteins in the course of bovine leukemia virus-induced leukemia in experimental sheep and I discuss how the obtained data may be useful in gaining a better understanding of the pathogenesis of the disease, diagnosis, and for the selection of possible therapeutic targets. In cattle, the disease is characterized by life-long persistent lymphocytosis leading to leukemia/lymphoma in about 5% of infected animals. In sheep, as opposed to cattle, the course of the disease is always fatal and clinical symptoms usually occur within a three-year period after infection. For this reason, sheep are an excellent experimental model of retrovirus-induced leukemia. This model can be useful for human pathology, as bovine leukemia virus is closely related to human T-lymphotropic virus type 1. The data presented here provide novel insights into the molecular mechanisms of the bovine leukemia virus-induced tumorigenic process and indicate the potential marker proteins both for monitoring progression of the disease and as possible targets of pharmacological intervention. A study of the proteome of B lymphocytes from four leukemic sheep revealed 11 proteins with altered expression. Among them, cytoskeleton and intermediate filament proteins were the most abundant, although proteins belonging to the other functional groups, i.e. enzymes, regulatory proteins, and transcription factors, were also present. It was found that trypsin inhibitor, platelet factor 4, thrombospondin 1, vasodilator-stimulated phosphoprotein, fibrinogen alpha chain, zyxin, filamin-A, and vitamin D-binding protein were downregulated, whereas cleavage and polyadenylation specificity factor subunit 5, non-POU domain-containing octamer-binding protein and small glutamine-rich tetratricopeptide repeat-containing protein alpha were upregulated. Discussed are the possible mechanisms of their altered expression and its significance in the bovine

  3. Comparative analysis of radiation- and virus-induced leukemias in BALB/c mice

    SciTech Connect

    Newcomb, E.W.; Binari, R.; Fleissner, E.

    1985-01-15

    Endogenous murine leukemia virus (MuLV) proviral copies were analyzed in thymomas induced in normal BALB/c (Fv-1b) and in Fv-1n congenic mice by X-irradiation. Both strains of mice developed leukemia with similar kinetics, indicating that N-tropism of endogenous MuLV was not a rate-limiting factor in development of disease. Southern blot analysis, using a probe specific for ecotropic virus and for ecotropic-specific sequences retained in pathogenic, env-recombinant viruses, showed that the majority of radiation leukemias lacked newly acquired, clonally integrated, proviruses. This was in contrast to virus-induced leukemias, which routinely exhibited several new proviral integration sites. When an internal proviral DNA restriction fragment was monitored, some radiation leukemias showed evidence of nonclonal infection, accounting for more frequent isolation of infectious virus from such leukemias. Differences in expression of T-cell surface antigens were found in X-ray-induced and virus-induced leukemias. All radiation leukemias were TL positive, whereas virus-induced leukemias were primarily negative for TL. Some differences were also found in Lyt-1 and Lyt-2 expression. The data as a whole suggest that, in the majority of cases, radiation leukemogenesis is not initiated by a viral route--that is, the sort of viral mechanism for which exogenous infection by known pathogenic MuLV is the paradigm.

  4. [Submicroscopic features of cells in the microenvironment of hematopoietic development of virus-induced Rauscher leukemia].

    PubMed

    Butenko, Z A; Naumenko, O I

    1993-06-01

    The study was made of submicroscopic changes in the cells of bone marrow and splenic microenvironment in mice developing virus-induced Rauscher leukemia. As shown by electron microscopy, ultrastructural cytochemistry and immunocytochemistry, ultrastructure of the complexes from the stromal and hemopoietic cells underwent noticeable alterations as early as the first days after the virus introduction. This suggests that bone marrow is the primary target of the virus in Rauscher leukemia. Affections of the macrophages, dendrite, interdigital and lymphoid cells of the spleen reflect their participation in the body defenses against the virus. Progressive shift of erythropoiesis from the bone marrow into the spleen is related to morphofunctional changes in the microenvironmental cells. The findings may be useful in consideration of cellular pathogenetic aspects of acute leukemia.

  5. Amphotropic murine leukemia viruses induce spongiform encephalomyelopathy

    PubMed Central

    Münk, Carsten; Löhler, Jürgen; Prassolov, Vladimir; Just, Ursula; Stockschläder, Marcus; Stocking, Carol

    1997-01-01

    Recombinants of amphotropic murine leukemia virus (A-MuLV) have found widespread use in retroviral vector systems due to their ability to efficiently and stably infect cells of several different species, including human. Previous work has shown that replication-competent recombinants containing the amphotropic env gene, encoding the major SU envelope glycoprotein that determines host tropism, induce lymphomas in vivo. We show here that these viruses also induce a spongiform encephalomyelopathy in mice inoculated perinatally. This fatal central nervous system disease is characterized by noninflammatory spongiform lesions of nerve and glial cells and their processes, and is associated with moderate astro- and microgliosis. The first clinical symptoms are ataxia, tremor, and spasticity, progressing to complete tetraparesis and incontinence, and finally death of the animal. Sequences within the amphotropic env gene are necessary for disease induction. Coinfection of A-MuLV recombinants with nonneuropathogenic ecotropic or polytropic MuLV drastically increases the incidence, degree, and distribution of the neurodegenerative disorder. The consequence of these results in view of the use of A-MuLV recombinants in the clinic is discussed. PMID:9159161

  6. Gene profiling of Graffi murine leukemia virus-induced lymphoid leukemias: identification of leukemia markers and Fmn2 as a potential oncogene.

    PubMed

    Charfi, Cyndia; Voisin, Véronique; Levros, Louis-Charles; Edouard, Elsy; Rassart, Eric

    2011-02-10

    The Graffi murine leukemia virus induces a large spectrum of leukemias in mice and thus provides a good model to compare the transcriptome of all types of leukemias. We analyzed the gene expression profiles of both T and B leukemias induced by the virus with DNA microarrays. Given that we considered that a 4-fold change in expression level was significant, 388 probe sets were associated to B, to T, or common to both leukemias. Several of them were not yet associated with lymphoid leukemia. We confirmed specific deregulation of Fmn2, Arntl2, Bfsp2, Gfra2, Gpm6a, and Gpm6b in B leukemia, of Nln, Fbln1, and Bmp7 in T leukemias, and of Etv5 in both leukemias. More importantly, we show that the mouse Fmn2 induced an anchorage-independent growth, a drastic modification in cell shape with a concomitant disruption of the actin cytoskeleton. Interestingly, we found that human FMN2 is overexpressed in approximately 95% of pre-B acute lymphoblastic leukemia with the highest expression levels in patients with a TEL/AML1 rearrangement. These results, surely related to the role of FMN2 in meiotic spindle maintenance, suggest its important role in leukemogenesis. Finally, we propose a new panel of genes potentially involved in T and/or B leukemias.

  7. Apparent feline leukemia virus-induced chronic lymphocytic leukemia and response to treatment.

    PubMed

    Kyle, Kristy N; Wright, Zachary

    2010-04-01

    Chylothorax secondary to chronic lymphocytic leukemia (CLL) was diagnosed in a feline leukemia virus (FeLV)-positive 8-year-old castrated male domestic shorthair feline. The leukemia resolved following therapy with chlorambucil, prednisone, cyclophosphamide, doxorubicin, and lomustine. To our knowledge, this is the first reported case of CLL in an FeLV-positive cat. Although a causative relationship cannot be proven, patients diagnosed with either disease may benefit from diagnostics to rule out the presence of the other concurrent condition. Copyright 2009 ISFM and AAFP. Published by Elsevier Ltd. All rights reserved.

  8. Genetic control of radiation leukemia virus-induced tumorigenesis. I. Role of the major murine histocompatibility complex, H-2

    PubMed Central

    1977-01-01

    Resistance to radiation leukemia virus-induced leukemogenesis is associated with the H-2D region of the H-2 complex, or with closely linked loci. The H-2Dd allele confers resistance ot the disease, while the H-2D-Q and H-2Ds alleles are associated with susceptibility. It is not clear whether Ir genes, or an alternative mechanism are responsible for the observed H-2-linked resistance to the disease. PMID:197195

  9. Outer nuclear membrane fusion of adjacent nuclei in varicella-zoster virus-induced syncytia.

    PubMed

    Wang, Wei; Yang, Lianwei; Huang, Xiumin; Fu, Wenkun; Pan, Dequan; Cai, Linli; Ye, Jianghui; Liu, Jian; Xia, Ningshao; Cheng, Tong; Zhu, Hua

    2017-09-11

    Syncytia formation has been considered important for cell-to-cell spread and pathogenesis of many viruses. As a syncytium forms, individual nuclei often congregate together, allowing close contact of nuclear membranes and possibly fusion to occur. However, there is currently no reported evidence of nuclear membrane fusion between adjacent nuclei in wild-type virus-induced syncytia. Varicella-zoster virus (VZV) is one typical syncytia-inducing virus that causes chickenpox and shingles in humans. Here, we report, for the first time, an interesting observation of apparent fusion of the outer nuclear membranes from juxtaposed nuclei that comprise VZV syncytia both in ARPE-19 human epithelial cells in vitro and in human skin xenografts in the SCID-hu mouse model in vivo. This work reveals a novel aspect of VZV-related cytopathic effect in the context of multinucleated syncytia. Additionally, the information provided by this study could be helpful for future studies on interactions of viruses with host cell nuclei. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Antibodies to CD9, a tetraspan transmembrane protein, inhibit canine distemper virus-induced cell-cell fusion but not virus-cell fusion.

    PubMed

    Schmid, E; Zurbriggen, A; Gassen, U; Rima, B; ter Meulen, V; Schneider-Schaulies, J

    2000-08-01

    Canine distemper virus (CDV) causes a life-threatening disease in several carnivores including domestic dogs. Recently, we identified a molecule, CD9, a member of the tetraspan transmembrane protein family, which facilitates, and antibodies to which inhibit, the infection of tissue culture cells with CDV (strain Onderstepoort). Here we describe that an anti-CD9 monoclonal antibody (MAb K41) did not interfere with binding of CDV to cells and uptake of virus. In addition, in single-step growth experiments, MAb K41 did not induce differences in the levels of viral mRNA and proteins. However, the virus release of syncytium-forming strains of CDV, the virus-induced cell-cell fusion in lytically infected cultures, and the cell-cell fusion of uninfected with persistently CDV-infected HeLa cells were strongly inhibited by MAb K41. These data indicate that anti-CD9 antibodies selectively block virus-induced cell-cell fusion, whereas virus-cell fusion is not affected.

  11. Molecular pathogenesis of feline leukemia virus-induced malignancies: insertional mutagenesis.

    PubMed

    Fujino, Yasuhito; Ohno, Koichi; Tsujimoto, Hajime

    2008-05-15

    Feline leukemia virus (FeLV), which is subclassified into three subgroups of A, B and C, is a pathogenic retrovirus in cats. FeLV-A is minimally pathogenic, FeLV-C can cause pure red cell aplasia, and FeLV-B is associated with a variety of pathogenic properties such as lymphoma, leukemia and anemia. FeLV-induced neoplasms are caused, at least in part, by somatically acquired insertional mutagenesis in which the integrated provirus may activate a proto-oncogene or disrupt a tumor suppressor gene. The common integration sites for FeLV have been identified in six loci with feline lymphomas: c-myc, flvi-1, flvi-2 (contains bmi-1), fit-1, pim-1 and flit-1. Oncogenic association of the loci includes that c-myc is known as a proto-oncogene, bmi-1 and pim-1 have been recognized as myc-collaborators, fit-1 appears to be closely linked to myb, and flit-1 insertion is shown to be associated with over-expression of a cellular gene, e.g. ACVRL1. Thus, identification of common integration sites for FeLV is a tenable model to clarify oncogenesis. Recent advances in molecular biology and cytogenetics have developed to rapidly detect numbers of retroviral integration sites by genome-wide large-scale analyses. Especially, polymerase chain reaction (PCR)-based strategies and chromosome analyses with fluorescence in situ hybridization (FISH) will be applicable for studies on FeLV.

  12. A generic screening platform for inhibitors of virus induced cell fusion using cellular electrical impedance

    PubMed Central

    Watterson, Daniel; Robinson, Jodie; Chappell, Keith J.; Butler, Mark S.; Edwards, David J.; Fry, Scott R.; Bermingham, Imogen M.; Cooper, Matthew A.; Young, Paul R.

    2016-01-01

    Fusion of the viral envelope with host cell membranes is an essential step in the life cycle of all enveloped viruses. Despite such a clear target for antiviral drug development, few anti-fusion drugs have progressed to market. One significant hurdle is the absence of a generic, high-throughput, reproducible fusion assay. Here we report that real time, label-free measurement of cellular electrical impedance can quantify cell-cell fusion mediated by either individually expressed recombinant viral fusion proteins, or native virus infection. We validated this approach for all three classes of viral fusion and demonstrated utility in quantifying fusion inhibition using antibodies and small molecule inhibitors specific for dengue virus and respiratory syncytial virus. PMID:26976324

  13. Phenotypes of murine leukemia virus-induced tumors: influence of 3' viral coding sequences.

    PubMed Central

    Ott, D E; Keller, J; Sill, K; Rein, A

    1992-01-01

    Murine leukemia viruses (MuLVs) induce leukemias and lymphomas in mice. We have used fluorescence-activated cell sorter analysis to determine the hematopoietic phenotypes of tumor cells induced by a number of MuLVs. Tumor cells induced by ecotropic Moloney, amphotropic 4070A, and 10A1 MuLVs and by two chimeric MuLVs, Mo(4070A) and Mo(10A1), were examined with antibodies to 13 lineage-specific cell surface markers found on myeloid cell, T-cell, and B-cell lineages. The chimeric Mo(4070A) and Mo(10A1) MuLVs, consisting of Moloney MuLV with the carboxy half of the Pol region and nearly all of the Env region of 4070A and 10A1, respectively, were constructed to examine the possible influence of these sequences on Moloney MuLV-induced tumor cell phenotypes. In some instances, these phenotypic analyses were supplemented by Southern blot analysis for lymphoid cell-specific genomic DNA rearrangements at the immunoglobulin heavy-chain, the T-cell receptor gamma, and the T-cell receptor beta loci. The results of our analysis showed that Moloney MuLV, 4070A, Mo(4070A), and Mo(10A1) induced mostly T-cell tumors. Moloney MuLV and Mo(4070A) induced a wide variety of T-cell phenotypes, ranging from immature to mature phenotypes, while 4070A induced mostly prothymocyte and double-negative (CD4- CD8-) T-cell tumors. The tumor phenotypes obtained with 10A1 and Mo(10A1) were each less variable than those obtained with the other MuLVs tested. 10A1 uniformly induced a tumor consisting of lineage marker-negative cells that lack lymphoid cell-specific DNA rearrangements and histologically appear to be early undifferentiated erythroid cell-like precursors. The Mo(10A1) chimera consistently induced an intermediate T-cell tumor. The chimeric constructions demonstrated that while 4070A 3' pol and env sequences apparently did not influence the observed tumor cell phenotypes, the 10A1 half of pol and env had a strong effect on the phenotypes induced by Mo(10A1) that resulted in a phenotypic

  14. Immunotherapy of murine leukemia. Efficacy of passive serum therapy of Friend leukemia virus-induced disease in immunocompromised mice

    SciTech Connect

    Genovesi, E.V.; Livnat, D.; Collins, J.J.

    1983-02-01

    Previous studies have demonstrated that the passive therapy of Friend murine leukemia virus (F-MuLV)-induced disease with chimpanzee anti-F-MuLV serum is accompanied by the development of host antiviral humoral and cellular immunity, the latter measurable in adoptive transfer protocols and by the ability of serum-protected mice to resist virus rechallenge. The present study was designed to further examine the contribution of various compartments of the host immune system to serum therapy itself, as well as to the acquired antiviral immunity that develops in serum-protected mice, through the use of naturally immunocompromised animals (e.g., nude athymic mice and natural killer (NK)-deficient beige mutant mice) or mice treated with immunoabrogating agents such as sublethal irradiation, cyclophosphamide (Cytoxan (Cy)), cortisone, and /sup 89/Sr. The studies in nude mice indicate that while mature T-cells are not needed for effective serum therapy, they do appear to be necessary for the long-term resistance of serum-protected mice to virus rechallenge and for the generation of the cell population(s) responsible for adoptive transfer of antiviral immunity. Furthermore, this acquired resistance is not due to virus neutralization by serum antibodies since antibody-negative, Cy-treated, serum-protected mice still reject the secondary virus infection. Lastly, while the immunocompromise systems examined did effect various host antiviral immune responses, none of them, including the NK-deficient beige mutation, significantly diminished the efficacy of the passive serum therapy of F-MuLV-induced disease.

  15. Genetic determinants of feline leukemia virus-induced lymphoid tumors: patterns of proviral insertion and gene rearrangement.

    PubMed

    Tsatsanis, C; Fulton, R; Nishigaki, K; Tsujimoto, H; Levy, L; Terry, A; Spandidos, D; Onions, D; Neil, J C

    1994-12-01

    The genetic basis of feline leukemia virus (FeLV)-induced lymphoma was investigated in a series of 63 lymphoid tumors and tumor cell lines of presumptive T-cell origin. These were examined for virus-induced rearrangements of the c-myc, flvi-2 (bmi-1), fit-1, and pim-1 loci, for T-cell receptor (TCR) gene rearrangements, and for the presence of env recombinant FeLV (FeLV-B). The myc locus was most frequently affected in naturally occurring lymphomas (32%; n = 38) either by transduction (21%) or by proviral insertion (11%). Proviral insertions were also common at flvi-2 (24%). The two other loci were occupied in a smaller number of the naturally occurring tumors (fit-1, 8%; pim-1, 5%). Examination of the entire set of tumors showed that significant numbers were affected at two (19%) or three (5%) of the loci. Occupation of the fit-1 locus was observed most frequently in tumors induced by FeLV-myc strains, while flvi-2 insertions occurred with similar frequency in the presence or absence of obvious c-myc activation. These results suggest a hierarchy of mutational events in the genesis of feline T-cell lymphomas by FeLV and implicate insertion at fit-1 as a late progression step. The strongest links observed were with T-cell development, as monitored by rearrangement status of the TCR beta-chain gene, which was positively associated with activation of myc (P < 0.001), and with proviral insertion at flvi-2 (P = 0.02). This analysis also revealed a genetically distinct subset of thymic lymphomas with unrearranged TCR beta-chain genes in which the known target loci were involved very infrequently. The presence of env recombinant FeLV (FeLV-B) showed a negative correlation with proviral insertion at fit-1, possibly due to the rapid onset of these tumors. These results shed further light on the multistep process of FeLV leukemogenesis and the relationships between lymphoid cell maturation and susceptibility to FeLV transformation.

  16. Characterization of leukemias with ETV6-ABL1 fusion

    PubMed Central

    Zaliova, Marketa; Moorman, Anthony V.; Cazzaniga, Giovanni; Stanulla, Martin; Harvey, Richard C.; Roberts, Kathryn G.; Heatley, Sue L.; Loh, Mignon L.; Konopleva, Marina; Chen, I-Ming; Zimmermannova, Olga; Schwab, Claire; Smith, Owen; Mozziconacci, Marie-Joelle; Chabannon, Christian; Kim, Myungshin; Frederik Falkenburg, J. H.; Norton, Alice; Marshall, Karen; Haas, Oskar A.; Starkova, Julia; Stuchly, Jan; Hunger, Stephen P.; White, Deborah; Mullighan, Charles G.; Willman, Cheryl L.; Stary, Jan; Trka, Jan; Zuna, Jan

    2016-01-01

    To characterize the incidence, clinical features and genetics of ETV6-ABL1 leukemias, representing targetable kinase-activating lesions, we analyzed 44 new and published cases of ETV6-ABL1-positive hematologic malignancies [22 cases of acute lymphoblastic leukemia (13 children, 9 adults) and 22 myeloid malignancies (18 myeloproliferative neoplasms, 4 acute myeloid leukemias)]. The presence of the ETV6-ABL1 fusion was ascertained by cytogenetics, fluorescence in-situ hybridization, reverse transcriptase-polymerase chain reaction and RNA sequencing. Genomic and gene expression profiling was performed by single nucleotide polymorphism and expression arrays. Systematic screening of more than 4,500 cases revealed that in acute lymphoblastic leukemia ETV6-ABL1 is rare in childhood (0.17% cases) and slightly more common in adults (0.38%). There is no systematic screening of myeloproliferative neoplasms; however, the number of ETV6-ABL1-positive cases and the relative incidence of acute lymphoblastic leukemia and myeloproliferative neoplasms suggest that in adulthood ETV6-ABL1 is more common in BCR-ABL1-negative chronic myeloid leukemia-like myeloproliferations than in acute lymphoblastic leukemia. The genomic profile of ETV6-ABL1 acute lymphoblastic leukemia resembled that of BCR-ABL1 and BCR-ABL1-like cases with 80% of patients having concurrent CDKN2A/B and IKZF1 deletions. In the gene expression profiling all the ETV6-ABL1-positive samples clustered in close vicinity to BCR-ABL1 cases. All but one of the cases of ETV6-ABL1 acute lymphoblastic leukemia were classified as BCR-ABL1-like by a standardized assay. Over 60% of patients died, irrespectively of the disease or age subgroup examined. In conclusion, ETV6-ABL1 fusion occurs in both lymphoid and myeloid leukemias; the genomic profile and clinical behavior resemble BCR-ABL1-positive malignancies, including the unfavorable prognosis, particularly of acute leukemias. The poor outcome suggests that treatment with

  17. Characterization of leukemias with ETV6-ABL1 fusion.

    PubMed

    Zaliova, Marketa; Moorman, Anthony V; Cazzaniga, Giovanni; Stanulla, Martin; Harvey, Richard C; Roberts, Kathryn G; Heatley, Sue L; Loh, Mignon L; Konopleva, Marina; Chen, I-Ming; Zimmermannova, Olga; Schwab, Claire; Smith, Owen; Mozziconacci, Marie-Joelle; Chabannon, Christian; Kim, Myungshin; Frederik Falkenburg, J H; Norton, Alice; Marshall, Karen; Haas, Oskar A; Starkova, Julia; Stuchly, Jan; Hunger, Stephen P; White, Deborah; Mullighan, Charles G; Willman, Cheryl L; Stary, Jan; Trka, Jan; Zuna, Jan

    2016-09-01

    To characterize the incidence, clinical features and genetics of ETV6-ABL1 leukemias, representing targetable kinase-activating lesions, we analyzed 44 new and published cases of ETV6-ABL1-positive hematologic malignancies [22 cases of acute lymphoblastic leukemia (13 children, 9 adults) and 22 myeloid malignancies (18 myeloproliferative neoplasms, 4 acute myeloid leukemias)]. The presence of the ETV6-ABL1 fusion was ascertained by cytogenetics, fluorescence in-situ hybridization, reverse transcriptase-polymerase chain reaction and RNA sequencing. Genomic and gene expression profiling was performed by single nucleotide polymorphism and expression arrays. Systematic screening of more than 4,500 cases revealed that in acute lymphoblastic leukemia ETV6-ABL1 is rare in childhood (0.17% cases) and slightly more common in adults (0.38%). There is no systematic screening of myeloproliferative neoplasms; however, the number of ETV6-ABL1-positive cases and the relative incidence of acute lymphoblastic leukemia and myeloproliferative neoplasms suggest that in adulthood ETV6-ABL1 is more common in BCR-ABL1-negative chronic myeloid leukemia-like myeloproliferations than in acute lymphoblastic leukemia. The genomic profile of ETV6-ABL1 acute lymphoblastic leukemia resembled that of BCR-ABL1 and BCR-ABL1-like cases with 80% of patients having concurrent CDKN2A/B and IKZF1 deletions. In the gene expression profiling all the ETV6-ABL1-positive samples clustered in close vicinity to BCR-ABL1 cases. All but one of the cases of ETV6-ABL1 acute lymphoblastic leukemia were classified as BCR-ABL1-like by a standardized assay. Over 60% of patients died, irrespectively of the disease or age subgroup examined. In conclusion, ETV6-ABL1 fusion occurs in both lymphoid and myeloid leukemias; the genomic profile and clinical behavior resemble BCR-ABL1-positive malignancies, including the unfavorable prognosis, particularly of acute leukemias. The poor outcome suggests that treatment with

  18. Proteolytic Cleavage of the Fusion Protein but Not Membrane Fusion Is Required for Measles Virus-Induced Immunosuppression In Vitro

    PubMed Central

    Weidmann, Armin; Maisner, Andrea; Garten, Wolfgang; Seufert, Marion; ter Meulen, Volker; Schneider-Schaulies, Sibylle

    2000-01-01

    Immunosuppression induced by measles virus (MV) is associated with unresponsiveness of peripheral blood lymphocytes (PBL) to mitogenic stimulation ex vivo and in vitro. In mixed lymphocyte cultures and in an experimental animal model, the expression of the MV glycoproteins on the surface of UV-inactivated MV particles, MV-infected cells, or cells transfected to coexpress the MV fusion (F) and the hemagglutinin (H) proteins was found to be necessary and sufficient for this phenomenon. We now show that MV fusion-inhibitory peptides do not interfere with the induction of immunosuppression in vitro, indicating that MV F-H-mediated fusion is essentially not involved in this process. Proteolytic cleavage of MV F0 protein by cellular proteases, such as furin, into the F1-F2 subunits is, however, an absolute requirement, since (i) the inhibitory activity of MV-infected BJAB cells was significantly impaired in the presence of a furin-inhibitory peptide and (ii) cells expressing or viruses containing uncleaved F0 proteins revealed a strongly reduced inhibitory activity which was improved following trypsin treatment. The low inhibitory activity of effector structures containing mainly F0 proteins was not due to an impaired F0-H interaction, since both surface expression and cocapping efficiencies were similar to those found with the authentic MV F and H proteins. These results indicate that the fusogenic activity of the MV F-H complexes can be uncoupled from their immunosuppressive activity and that the immunosuppressive domains of these proteins are exposed only after proteolytic activation of the MV F0 protein. PMID:10644371

  19. Role of Ca++ in virus-induced membrane fusion. Ca++ accumulation and ultrastructural changes induced by Sendai virus in chicken erythrocytes

    PubMed Central

    1978-01-01

    Some of the ultrastructural (freeze-etching technique), morphological, and biochemical effects of Sendai virus interaction with chicken erythrocytes have been studied under fusogenic (in the presence of CaCl2) and nonfusogenic (in the presence of ethyleneglycol-bis-N,N'- tetraacetic acid, [EGTA]) conditions. The following phenomena occur, irrespective of the presence of CaCl2 or EGTA: (a) binding of iodinated virus particles to chicken erythrocytes at 4 degrees C and their partial release from the cells at 37 degrees C; (b) gradual incorporation of the viral envelope and viral M-protein into plasma membrane, as visualized in the protoplasmic and exoplasmic fracture (P and E, respectively) faces of the membrane; and (c) virus-dependent transient clustering of intramembrane particles at 4 degrees C, which is reversible after transferring the cells back to 37 degrees C. The following virus-induced phenomena occur only in the presence of CaCl2: (a) rounding of cells followed by their fusion; (b) transient decrease in the density of intramembrane particles; and (c) the virus induces uptake of 45CaCl2 by chicken erythrocytes. The uptake is specific as it is inhibited by LaCl3, and no accumulation of [14C]glucose-1-phosphate ([14C]G-1-P) could be observed under the 45 CaCl2 uptake conditions. The data show that fusion of virus with plasma membrane is a Ca++- independent process and, as such, it should be distinguished from the virus-induced membrane-membrane and cell fusion processes. The latter is absolutely dependent on the rise of intracellular Ca++, as reflected by the fact that Ca++-induced rounding of chicken erythrocytes always precedes fusion (Volsky, D. and A. Loyter. 1977.Biochim. Biophys. Acta 471:253--259). PMID:211140

  20. NUP98-MLL fusion in human acute myeloblastic leukemia.

    PubMed

    Kaltenbach, Sophie; Soler, Gwendoline; Barin, Carole; Gervais, Carine; Bernard, Olivier A; Penard-Lacronique, Virginie; Romana, Serge P

    2010-09-30

    Posttranscriptional modifications of histones play important roles in the control of chromatin structure and transcription. H3K4 (histone H3 lysine 4) methylation by the SET domain of the trithorax-group protein MLL (mixed-lineage leukemia) is important for the control of homeobox (HOX) gene expression during development. MLL is tethered to the HOXA locus through interaction of its amino-terminus with menin. MLL fusion proteins associated with human leukemia contain the menin interaction peptide and frequently recruit H3K79 (histone H3 lysine 79) methylation activity. This allows sustained expression of HOXA genes important for cellular transformation. We have characterized a novel recurrent chromosomal aberration, inv(11)(p15q23), as an isolated chromosomal abnormality in 2 patients with acute myeloid leukemia. This aberration is predicted to result in the expression of an NUP98 (nucleoporin 98 kDa)-MLL fusion protein that is unable to interact with menin. As expected, low levels of HOXA gene expression were observed in the patients' samples. This fusion protein is predicted to participate in cellular transformation by activating MLL targets other than HOXA genes.

  1. In vitro generation of cytotoxic lymphocytes against radiation-and radiation leukemia virus-induced tumors. III. Suppression of anti-tumor immunity in vitro by lymphocytes of mice undergoing radiation leukemia virus-induced leukemogenesis

    SciTech Connect

    Yefenof, E.; Meidav, A.; Kedar, E.

    1980-12-01

    Adult C57BL/6 mice exposed to fractionated irradiation or inoculated with the radiation leukemia virus (RadLV), develop high incidence (80 to 100%) of lymphatic leukemias within 3 to 6 months. RadLV-induced lymphomas can elicit cytotoxic responses in vitro in lymphocytes of preimmunized syngeneic mice. As soon as 5 d after RadLV inoculation, and during the entire leukemogenic process, suppressor T cells are detectable in the spleen that are capable of specifically abrogating generation of syngeneic anti-tumor cytotoxic cells in vitro. Mice exposed to fractionated x irradiation do not develop suppressor cells. These findings suggest that although RadLV has been isolated from radiation-induced leukemias, x-ray- and RadLV-induced leukemogenesis do not seem to involve a common viral etilogy, and that induction of suppressor cells during RadLV leukemogenesis may be essential for tumor progression.

  2. The SNARE Protein Syp71 Is Essential for Turnip Mosaic Virus Infection by Mediating Fusion of Virus-Induced Vesicles with Chloroplasts

    PubMed Central

    Hou, Xilin; Sanfaçon, Hélène; Wang, Aiming

    2013-01-01

    All positive-strand RNA viruses induce the biogenesis of cytoplasmic membrane-bound virus factories for viral genome multiplication. We have previously demonstrated that upon plant potyvirus infection, the potyviral 6K2 integral membrane protein induces the formation of ER-derived replication vesicles that subsequently target chloroplasts for robust genome replication. Here, we report that following the trafficking of the Turnip mosaic potyvirus (TuMV) 6K2 vesicles to chloroplasts, 6K2 vesicles accumulate at the chloroplasts to form chloroplast-bound elongated tubular structures followed by chloroplast aggregation. A functional actomyosin motility system is required for this process. As vesicle trafficking and fusion in planta are facilitated by a superfamily of proteins known as SNAREs (soluble N-ethylmaleimide-sensitive-factor attachment protein receptors), we screened ER-localized SNARES or SNARE-like proteins for their possible involvement in TuMV infection. We identified Syp71 and Vap27-1 that colocalize with the chloroplast-bound 6K2 complex. Knockdown of their expression using a Tobacco rattle virus (TRV)-based virus-induced gene silencing vector showed that Syp71 but not Vap27-1 is essential for TuMV infection. In Syp71-downregulated plant cells, the formation of 6K2-induced chloroplast-bound elongated tubular structures and chloroplast aggregates is inhibited and virus accumulation is significantly reduced, but the trafficking of the 6K2 vesicles from the ER to chloroplast is not affected. Taken together, these data suggest that Syp71 is a host factor essential for successful virus infection by mediating the fusion of the virus-induced vesicles with chloroplasts during TuMV infection. PMID:23696741

  3. The SNARE protein Syp71 is essential for turnip mosaic virus infection by mediating fusion of virus-induced vesicles with chloroplasts.

    PubMed

    Wei, Taiyun; Zhang, Changwei; Hou, Xilin; Sanfaçon, Hélène; Wang, Aiming

    2013-01-01

    All positive-strand RNA viruses induce the biogenesis of cytoplasmic membrane-bound virus factories for viral genome multiplication. We have previously demonstrated that upon plant potyvirus infection, the potyviral 6K2 integral membrane protein induces the formation of ER-derived replication vesicles that subsequently target chloroplasts for robust genome replication. Here, we report that following the trafficking of the Turnip mosaic potyvirus (TuMV) 6K2 vesicles to chloroplasts, 6K2 vesicles accumulate at the chloroplasts to form chloroplast-bound elongated tubular structures followed by chloroplast aggregation. A functional actomyosin motility system is required for this process. As vesicle trafficking and fusion in planta are facilitated by a superfamily of proteins known as SNAREs (soluble N-ethylmaleimide-sensitive-factor attachment protein receptors), we screened ER-localized SNARES or SNARE-like proteins for their possible involvement in TuMV infection. We identified Syp71 and Vap27-1 that colocalize with the chloroplast-bound 6K2 complex. Knockdown of their expression using a Tobacco rattle virus (TRV)-based virus-induced gene silencing vector showed that Syp71 but not Vap27-1 is essential for TuMV infection. In Syp71-downregulated plant cells, the formation of 6K2-induced chloroplast-bound elongated tubular structures and chloroplast aggregates is inhibited and virus accumulation is significantly reduced, but the trafficking of the 6K2 vesicles from the ER to chloroplast is not affected. Taken together, these data suggest that Syp71 is a host factor essential for successful virus infection by mediating the fusion of the virus-induced vesicles with chloroplasts during TuMV infection.

  4. Herpes Simplex Virus 1 Glycoprotein M and the Membrane-Associated Protein UL11 Are Required for Virus-Induced Cell Fusion and Efficient Virus Entry

    PubMed Central

    Kim, In-Joong; Chouljenko, Vladimir N.; Walker, Jason D.

    2013-01-01

    Herpes simplex virus 1 (HSV-1) facilitates virus entry into cells and cell-to-cell spread by mediating fusion of the viral envelope with cellular membranes and fusion of adjacent cellular membranes. Although virus strains isolated from herpetic lesions cause limited cell fusion in cell culture, clinical herpetic lesions typically contain large syncytia, underscoring the importance of cell-to-cell fusion in virus spread in infected tissues. Certain mutations in glycoprotein B (gB), gK, UL20, and other viral genes drastically enhance virus-induced cell fusion in vitro and in vivo. Recent work has suggested that gB is the sole fusogenic glycoprotein, regulated by interactions with the viral glycoproteins gD, gH/gL, and gK, membrane protein UL20, and cellular receptors. Recombinant viruses were constructed to abolish either gM or UL11 expression in the presence of strong syncytial mutations in either gB or gK. Virus-induced cell fusion caused by deletion of the carboxyl-terminal 28 amino acids of gB or the dominant syncytial mutation in gK (Ala to Val at amino acid 40) was drastically reduced in the absence of gM. Similarly, syncytial mutations in either gB or gK did not cause cell fusion in the absence of UL11. Neither the gM nor UL11 gene deletion substantially affected gB, gC, gD, gE, and gH glycoprotein synthesis and expression on infected cell surfaces. Two-way immunoprecipitation experiments revealed that the membrane protein UL20, which is found as a protein complex with gK, interacted with gM while gM did not interact with other viral glycoproteins. Viruses produced in the absence of gM or UL11 entered into cells more slowly than their parental wild-type virus strain. Collectively, these results indicate that gM and UL11 are required for efficient membrane fusion events during virus entry and virus spread. PMID:23678175

  5. Identification of a novel common proviral integration site, flit-1, in feline leukemia virus induced thymic lymphoma.

    PubMed

    Fujino, Yasuhito; Liao, Chun-Peng; Zhao, Yan Shi; Pan, Judong; Mathes, Lawrence E; Hayes, Kathleen A; Ohno, Koichi; Tsujimoto, Hajime; Roy-Burman, Pradip

    2009-03-30

    A new proviral integration site for feline leukemia virus (FeLV), termed flit-1, was identified from feline thymic lymphoma. Among 35 FeLV-related tumors examined, 5 of 25 thymic lymphomas demonstrated proviral insertion within flit-1 locus whereas none of four alimentary and five multicentric lymphomas and one T-lymphoid leukemia examined had rearrangement in this region. Extensive sequence analysis has shown that flit-1, which is noncoding, is conserved on human chromosome 12 and mouse chromosome 15. The human and murine homologs of flit-1 are positioned approximately 30-kb upstream to activin-A receptor type II-like 1 (ACVRL1/ALK1) gene. Expression of ACVRL1 mRNA was examined in two of five lymphomas with flit-1 rearrangement and detected in both of the two whereas normal thymuses and seven lymphoid tumors without flit-1 rearrangement had no detectable expression. Therefore, flit-1 appears to represent a novel FeLV proviral common integration domain that may influence lymphomagenesis as insertional mutagenesis.

  6. Inefficient viral replication of bovine leukemia virus induced by spontaneous deletion mutation in the G4 gene.

    PubMed

    Murakami, Hironobu; Uchiyama, Jumpei; Nikaido, Sae; Sato, Reiichiro; Sakaguchi, Masahiro; Tsukamoto, Kenji

    2016-10-01

    Enzootic bovine leucosis is caused by bovine leukemia virus (BLV) infection, which is highly prevalent in several regions of the world and significantly impacts the livestock industry. In BLV infection, the proviral load in the blood reflects disease progression. Although the BLV genome is highly conserved among retroviruses, genetic variation has been reported. However, the relationship between proviral load and genetic variation is poorly understood. In this study, we investigated the changes in proviral load in BLV-infected cattle in Japan and then identified and analysed a BLV strain pvAF967 that had a static proviral load. First, examining the proviral load in the aleukaemic cattle in 2014 and 2015, cow AF967 showed a static proviral load, while the other cows showed significant increases in proviral load. Sequencing the provirus in cow AF967 showed a deletion of 12 nt located in the G4 gene. An in vitro assay system using BLV molecular clone was set up to evaluate viral replication and production. In this in vitro assay, the deletion mutation in the G4 gene resulted in a significant decrease in viral replication and production. In addition, we showed that the deletion mutation did not affect the viral transcriptional activity of Tax protein, which is also important for virus replication. The emergence of strain pvAF967 that showed a static proviral load, combined with other retrovirus evolutionary traits, suggests that some BLV strains may have evolved to be symbiotic with cattle.

  7. Novel cytotoxic exhibition mode of antimicrobial peptide anoplin in MEL cells, the cell line of murine Friend leukemia virus-induced leukemic cells.

    PubMed

    Zhu, Li-Na; Fu, Cai-Yun; Zhang, Shi-Fu; Chen, Wei; Jin, Yuan-Ting; Zhao, Fu-Kun

    2013-09-01

    Anoplin is a recently discovered antimicrobial peptide (AMP) isolated from the venom sac of the spider wasp Anoplius samariensis, and it is one of the shortest α-helical AMP found naturally to date consisting of only ten amino acids. Previous results showed that anoplin exhibits potent antimicrobial activity but little hemolytic activity. In this study, we synthesized anoplin, studied its cytotoxicity in Friend virus-induced leukemia cells [murine erythroleukemia (MEL) cells], and proposed its possible mechanism. Our results showed that anoplin could inhibit the proliferation of MEL cells in a dose-dependent and time-dependent manner via disrupting the integrity of cell membrane, which indicated that anoplin exerts its cytotoxicity efficacy. In addition, the cell cycle distribution of MEL cells was arrested in the G₀/G₁ phase significantly. However, anoplin could not induce obvious apoptosis in MEL cells, as well as anoplin could not induce visible changes on morphology and quantity in the bone marrow cells isolated from normal mice. All of these results indicate that anoplin, as generally believed, is a selective AMP, a value characteristic in the design of safe therapeutic agents. The cytotoxicity of anoplin on MEL cells was mainly attributable to the plasma membrane perturbation and also to the intracellular events such as the arrest of cell cycle. Although this is an initial study that explored the activity of anoplin in vitro rather than in vivo, with the increasing resistance of conventional chemotherapy, there is no doubt that anoplin has desirable feature to be developed as a novel and selective anticancer agent. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.

  8. Identification of a gag-encoded cytotoxic T-lymphocyte epitope from FBL-3 leukemia shared by Friend, Moloney, and Rauscher murine leukemia virus-induced tumors.

    PubMed Central

    Chen, W; Qin, H; Chesebro, B; Cheever, M A

    1996-01-01

    FBL-3 is a highly immunogenic murine leukemia of C57BL/6 origin induced by Friend murine leukemia virus (MuLV). Immunization of C57BL/6 mice with FBL-3 readily elicits CD8+ cytotoxic T lymphocytes (CTL) capable of lysing FBL-3 as well as syngeneic leukemias induced by Moloney and Rauscher MuLV. The aim of this current study was to identify the immunogenic epitope(s) recognized by the FBL-3-specific CD8+ CTL. A series of FBL-3-specific CD8+ CTL clones were generated from C57BL/6 mice immunized to FBL-3. The majority of CTL clones (32 of 38) were specific for F-MuLV gag-encoded antigen. By using a series of recombinant vaccinia viruses expressing full-length and truncated F-MuLV gag genes, the antigenic epitope recognized by the FBL-3 gag-specific CTL clones, as well as by bulk-cultured CTL from spleens of mice immune to FBL-3, was localized to the leader sequence of gPr80gag protein. The precise amino acid sequence of the CTL epitope in the leader sequence was identified as CCLCLTVFL (positions 85-93) by examining lysis of targets incubated with a series of synthetic leader sequence peptides. No evidence of other CTL epitopes in the gPr80gag or Pr65gag core virion structural polyproteins was found. The identity of CCLCLTVFL as the target peptide was validated by showing that immunization with the peptide elicited CTL that lysed FBL-3. The CTL elicited by the Gag peptide also specifically lysed syngeneic leukemia cells induced by Moloney and Rauscher MuLV (MBL-2 and RBL-5). The transmembrane peptide was shown to be the major gag-encoded antigenic epitope recognized by bulk-cultured CTL derived from C57BL/6 mice immunized to MBL-2 or RBL-5. Thus, the CTL epitope of FBL-3 is localized to the transmembrane anchor domain of the nonstructural Gag polyprotein and is shared by leukemia/lymphoma cell lines induced by Friend, Moloney, and Rauscher MuLV. PMID:8892898

  9. Systematic Classification of Mixed-Lineage Leukemia Fusion Partners Predicts Additional Cancer Pathways.

    PubMed

    Marschalek, Rolf

    2016-03-01

    Chromosomal translocations of the human mixed-lineage leukemia (MLL) gene have been analyzed for more than 20 yr at the molecular level. So far, we have collected about 80 direct MLL fusions (MLL-X alleles) and about 120 reciprocal MLL fusions (X-MLL alleles). The reason for the higher amount of reciprocal MLL fusions is that the excess is caused by 3-way translocations with known direct fusion partners. This review is aiming to propose a solution for an obvious problem, namely why so many and completely different MLL fusion alleles are always leading to the same leukemia phenotypes (ALL, AML, or MLL). This review is aiming to explain the molecular consequences of MLL translocations, and secondly, the contribution of the different fusion partners. A new hypothesis will be posed that can be used for future research, aiming to find new avenues for the treatment of this particular leukemia entity.

  10. Systematic Classification of Mixed-Lineage Leukemia Fusion Partners Predicts Additional Cancer Pathways

    PubMed Central

    2016-01-01

    Chromosomal translocations of the human mixed-lineage leukemia (MLL) gene have been analyzed for more than 20 yr at the molecular level. So far, we have collected about 80 direct MLL fusions (MLL-X alleles) and about 120 reciprocal MLL fusions (X-MLL alleles). The reason for the higher amount of reciprocal MLL fusions is that the excess is caused by 3-way translocations with known direct fusion partners. This review is aiming to propose a solution for an obvious problem, namely why so many and completely different MLL fusion alleles are always leading to the same leukemia phenotypes (ALL, AML, or MLL). This review is aiming to explain the molecular consequences of MLL translocations, and secondly, the contribution of the different fusion partners. A new hypothesis will be posed that can be used for future research, aiming to find new avenues for the treatment of this particular leukemia entity. PMID:26709255

  11. Activation of the prolactin receptor gene by promoter insertion in a Moloney murine leukemia virus-induced rat thymoma.

    PubMed Central

    Barker, C S; Bear, S E; Keler, T; Copeland, N G; Gilbert, D J; Jenkins, N A; Yeung, R S; Tsichlis, P N

    1992-01-01

    The prolactin receptor (Prlr) and growth hormone receptor (Ghr) genes and the Moloney murine leukemia virus integration-2 (Mlvi-2) locus were mapped to mouse chromosome 15 and human chromosome 5 bands p12-p14. To examine the potential relationship between Mlvi-2 and the genes encoding the growth hormone receptor and the prolactin receptor, we determined the chromosomal location of all three loci in the rat, using a panel of rat-mouse somatic cell hybrids, and in the mouse, using a panel of (C57BL/6J x Mus spretus)F1 x C57BL/6J interspecific backcross mice. These analyses revealed that Ghr, Prlr, and Mlvi-2 map to chromosome 2 in the rat and to chromosome 15 in the mouse, in close proximity with each other. Pulsed-field gel electrophoresis of rat genomic DNA showed no overlaps between the gene encoding the prolactin receptor and the remaining loci. Moreover, expression of the prolactin receptor was not affected by provirus insertion in Mlvi-2. During these studies, however, we detected one T-cell lymphoma line (2779) in which the prolactin receptor gene was activated by provirus integration. Sequence analysis of polymerase chain reaction-derived cDNA clones showed that the prolactin receptor RNA message initiates at the 5' long terminal repeat and utilizes the splice donor site 5' of the gag gene to splice the viral sequences onto exon 1 of the prolactin receptor. This message is predicted to encode the intact prolactin receptor protein product. Exposure of the T-cell lymphoma line 2779 to prolactin promoted cellular proliferation. Images PMID:1404614

  12. Novel principles of gamma-retroviral insertional transcription activation in murine leukemia virus-induced end-stage tumors.

    PubMed

    Sokol, Martin; Wabl, Matthias; Ruiz, Irene Rius; Pedersen, Finn Skou

    2014-05-19

    Insertional mutagenesis screens of retrovirus-induced mouse tumors have proven valuable in human cancer research and for understanding adverse effects of retroviral-based gene therapies. In previous studies, the assignment of mouse genes to individual retroviral integration sites has been based on close proximity and expression patterns of annotated genes at target positions in the genome. We here employed next-generation RNA sequencing to map retroviral-mouse chimeric junctions genome-wide, and to identify local patterns of transcription activation in T-lymphomas induced by the murine leukemia gamma-retrovirus SL3-3. Moreover, to determine epigenetic integration preferences underlying long-range gene activation by retroviruses, the colocalization propensity with common epigenetic enhancer markers (H3K4Me1 and H3K27Ac) of 6,117 integrations derived from end-stage tumors of more than 2,000 mice was examined. We detected several novel mechanisms of retroviral insertional mutagenesis: bidirectional activation of mouse transcripts on opposite sides of a provirus including transcription of unannotated mouse sequence; sense/antisense-type activation of genes located on opposite DNA strands; tandem-type activation of distal genes that are positioned adjacently on the same DNA strand; activation of genes that are not the direct integration targets; combination-type insertional mutagenesis, in which enhancer activation, alternative chimeric splicing and retroviral promoter insertion are induced by a single retrovirus. We also show that irrespective of the distance to transcription start sites, the far majority of retroviruses in end-stage tumors colocalize with H3K4Me1 and H3K27Ac-enriched regions in murine lymphoid tissues. We expose novel retrovirus-induced host transcription activation patterns that reach beyond a single and nearest annotated gene target. Awareness of this previously undescribed layer of complexity may prove important for elucidation of adverse effects

  13. Targeting fusion protein/corepressor contact restores differentiation response in leukemia cells

    PubMed Central

    Racanicchi, Serena; Maccherani, Chiara; Liberatore, Concetta; Billi, Monia; Gelmetti, Vania; Panigada, Maddalena; Rizzo, Giovanni; Nervi, Clara; Grignani, Francesco

    2005-01-01

    The AML1/ETO and PML/RARα leukemia fusion proteins induce acute myeloid leukemia by acting as transcriptional repressors. They interact with corepressors, such as N-CoR and SMRT, that recruit a multiprotein complex containing histone deacetylases on crucial myeloid differentiation genes. This leads to gene repression contributing to generate a differentiation block. We expressed in leukemia cells containing PML/RARα and AML1/ETO N-CoR protein fragments derived from fusion protein/corepressor interaction surfaces. This blocks N-CoR/SMRT binding by these fusion proteins, and disrupts the repressor protein complex. In consequence, the expression of genes repressed by these fusion proteins increases and differentiation response to vitamin D3 and retinoic acid is restored in previously resistant cells. The alteration of PML/RARα–N-CoR/SMRT connections triggers proteasomal degradation of the fusion protein. The N-CoR fragments are biologically effective also when directly transduced by virtue of a protein transduction domain. Our data indicate that fusion protein activity is permanently required to maintain the leukemia phenotype and show the route to developing a novel therapeutic approach for leukemia, based on its molecular pathogenesis. PMID:15729358

  14. Molecular findings in childhood leukemia in Brazil: high frequency of MLL-ENL Fusion/t(11;19) in infant leukemia.

    PubMed

    Marques, Ester Augusta Lima Vinhas; Neves, Lidia; Fonseca, Tereza Cristina; Lins, Mecneide Mendes; Pedrosa, Francisco; Lucena-Silva, Norma

    2011-08-01

    Translocations involving chromosome 11q23 are frequently found in pediatric leukemia, especially in infants. The mixed lineage leukemia (MLL)-AF4 fusion/t(4;11) is mostly found in acute lymphoblastic leukemia (ALL) and MLL-AF9 fusion/t(9;11) in acute myeloid leukemia (AML). We study 441 consecutive new cases of childhood leukemia diagnosed in Brazil. Chromosomal translocation was determined solely by conventional polymerase chain reaction (PCR) in 72 out of 265 ALL and in 43 out of 103 AML. MLL-AF4 fusion/t(4;11) was detected in 3 out of 265 ALL and MLL-AF9 fusion/t(9;11) in 4 out of 103 of AML. MLL-rearrangements were presented in 7 out of 23 infant leukemia, whose 5 were MLL-ENL fusion/t(11;19). No fusion MLL-AF4 fusion/t(4;11) was found. Other translocation frequencies differed from that reported for an American population suggesting interethnic differences on chromosomal translocations frequencies in acute leukemia.

  15. Characterization of a newly identified ETV6-NTRK3 fusion transcript in acute myeloid leukemia

    PubMed Central

    2011-01-01

    Background Characterization of novel fusion genes in acute leukemia is important for gaining information about leukemia genesis. We describe the characterization of a new ETV6 fusion gene in acute myeloid leukemia (AML) FAB M0 as a result of an uncommon translocation involving chromosomes 12 and 15. Methods The ETV6 locus at 12p13 was shown to be translocated and to constitute the 5' end of the fusion product by ETV6 break apart fluorescence in situ hybridisation (FISH). To identify a fusion partner 3' rapid amplification of cDNA-ends with polymerase chain reaction (RACE PCR) was performed followed by cloning and sequencing. Results The NTRK3 gene on chromosome 15 was found to constitute the 3' end of the fusion gene and the underlying ETV6-NTRK3 rearrangement was verified by reverse transcriptase PCR. No RNA of the reciprocal NTRK3-ETV6 fusion gene could be detected. Conclusion We have characterized a novel ETV6-NTRK3 fusion transcript which has not been previously described in AML FAB M0 by FISH and RACE PCR. ETV6-NTRK3 rearrangements have been described in secretory breast carcinoma and congenital fibrosarcoma. PMID:21401966

  16. Transcriptome sequencing in pediatric acute lymphoblastic leukemia identifies fusion genes associated with distinct DNA methylation profiles.

    PubMed

    Marincevic-Zuniga, Yanara; Dahlberg, Johan; Nilsson, Sara; Raine, Amanda; Nystedt, Sara; Lindqvist, Carl Mårten; Berglund, Eva C; Abrahamsson, Jonas; Cavelier, Lucia; Forestier, Erik; Heyman, Mats; Lönnerholm, Gudmar; Nordlund, Jessica; Syvänen, Ann-Christine

    2017-08-14

    Structural chromosomal rearrangements that lead to expressed fusion genes are a hallmark of acute lymphoblastic leukemia (ALL). In this study, we performed transcriptome sequencing of 134 primary ALL patient samples to comprehensively detect fusion transcripts. We combined fusion gene detection with genome-wide DNA methylation analysis, gene expression profiling, and targeted sequencing to determine molecular signatures of emerging ALL subtypes. We identified 64 unique fusion events distributed among 80 individual patients, of which over 50% have not previously been reported in ALL. Although the majority of the fusion genes were found only in a single patient, we identified several recurrent fusion gene families defined by promiscuous fusion gene partners, such as ETV6, RUNX1, PAX5, and ZNF384, or recurrent fusion genes, such as DUX4-IGH. Our data show that patients harboring these fusion genes displayed characteristic genome-wide DNA methylation and gene expression signatures in addition to distinct patterns in single nucleotide variants and recurrent copy number alterations. Our study delineates the fusion gene landscape in pediatric ALL, including both known and novel fusion genes, and highlights fusion gene families with shared molecular etiologies, which may provide additional information for prognosis and therapeutic options in the future.

  17. Determination of the minimal fusion peptide of bovine leukemia virus gp30

    SciTech Connect

    Lorin, Aurelien; Lins, Laurence; Stroobant, Vincent; Brasseur, Robert . E-mail: brasseur.r@fsagx.ac.be; Charloteaux, Benoit

    2007-04-13

    In this study, we determined the minimal N-terminal fusion peptide of the gp30 of the bovine leukemia virus on the basis of the tilted peptide theory. We first used molecular modelling to predict that the gp30 minimal fusion peptide corresponds to the 15 first residues. Liposome lipid-mixing and leakage assays confirmed that the 15-residue long peptide induces fusion in vitro and that it is the shortest peptide inducing optimal fusion since longer peptides destabilize liposomes to the same extent but not shorter ones. The 15-residue long peptide can thus be considered as the minimal fusion peptide. The effect of mutations reported in the literature was also investigated. Interestingly, mutations related to glycoproteins unable to induce syncytia in cell-cell fusion assays correspond to peptides predicted as non-tilted. The relationship between obliquity and fusogenicity was also confirmed in vitro for one tilted and one non-tilted mutant peptide.

  18. Expression of Leukemia-Associated Nup98 Fusion Proteins Generates an Aberrant Nuclear Envelope Phenotype.

    PubMed

    Fahrenkrog, Birthe; Martinelli, Valérie; Nilles, Nadine; Fruhmann, Gernot; Chatel, Guillaume; Juge, Sabine; Sauder, Ursula; Di Giacomo, Danika; Mecucci, Cristina; Schwaller, Jürg

    2016-01-01

    Chromosomal translocations involving the nucleoporin NUP98 have been described in several hematopoietic malignancies, in particular acute myeloid leukemia (AML). In the resulting chimeric proteins, Nup98's N-terminal region is fused to the C-terminal region of about 30 different partners, including homeodomain (HD) transcription factors. While transcriptional targets of distinct Nup98 chimeras related to immortalization are relatively well described, little is known about other potential cellular effects of these fusion proteins. By comparing the sub-nuclear localization of a large number of Nup98 fusions with HD and non-HD partners throughout the cell cycle we found that while all Nup98 chimeras were nuclear during interphase, only Nup98-HD fusion proteins exhibited a characteristic speckled appearance. During mitosis, only Nup98-HD fusions were concentrated on chromosomes. Despite the difference in localization, all tested Nup98 chimera provoked morphological alterations in the nuclear envelope (NE), in particular affecting the nuclear lamina and the lamina-associated polypeptide 2α (LAP2α). Importantly, such aberrations were not only observed in transiently transfected HeLa cells but also in mouse bone marrow cells immortalized by Nup98 fusions and in cells derived from leukemia patients harboring Nup98 fusions. Our findings unravel Nup98 fusion-associated NE alterations that may contribute to leukemogenesis.

  19. Expression of Leukemia-Associated Nup98 Fusion Proteins Generates an Aberrant Nuclear Envelope Phenotype

    PubMed Central

    Fahrenkrog, Birthe; Martinelli, Valérie; Nilles, Nadine; Fruhmann, Gernot; Chatel, Guillaume; Juge, Sabine; Sauder, Ursula; Di Giacomo, Danika; Mecucci, Cristina; Schwaller, Jürg

    2016-01-01

    Chromosomal translocations involving the nucleoporin NUP98 have been described in several hematopoietic malignancies, in particular acute myeloid leukemia (AML). In the resulting chimeric proteins, Nup98's N-terminal region is fused to the C-terminal region of about 30 different partners, including homeodomain (HD) transcription factors. While transcriptional targets of distinct Nup98 chimeras related to immortalization are relatively well described, little is known about other potential cellular effects of these fusion proteins. By comparing the sub-nuclear localization of a large number of Nup98 fusions with HD and non-HD partners throughout the cell cycle we found that while all Nup98 chimeras were nuclear during interphase, only Nup98-HD fusion proteins exhibited a characteristic speckled appearance. During mitosis, only Nup98-HD fusions were concentrated on chromosomes. Despite the difference in localization, all tested Nup98 chimera provoked morphological alterations in the nuclear envelope (NE), in particular affecting the nuclear lamina and the lamina-associated polypeptide 2α (LAP2α). Importantly, such aberrations were not only observed in transiently transfected HeLa cells but also in mouse bone marrow cells immortalized by Nup98 fusions and in cells derived from leukemia patients harboring Nup98 fusions. Our findings unravel Nup98 fusion-associated NE alterations that may contribute to leukemogenesis. PMID:27031510

  20. Acute myeloid leukemia fusion proteins deregulate genes involved in stem cell maintenance and DNA repair

    PubMed Central

    Alcalay, Myriam; Meani, Natalia; Gelmetti, Vania; Fantozzi, Anna; Fagioli, Marta; Orleth, Annette; Riganelli, Daniela; Sebastiani, Carla; Cappelli, Enrico; Casciari, Cristina; Sciurpi, Maria Teresa; Mariano, Angela Rosa; Minardi, Simone Paolo; Luzi, Lucilla; Muller, Heiko; Di Fiore, Pier Paolo; Frosina, Guido; Pelicci, Pier Giuseppe

    2003-01-01

    Acute myelogenous leukemias (AMLs) are genetically heterogeneous and characterized by chromosomal rearrangements that produce fusion proteins with aberrant transcriptional regulatory activities. Expression of AML fusion proteins in transgenic mice increases the risk of myeloid leukemias, suggesting that they induce a preleukemic state. The underlying molecular and biological mechanisms are, however, unknown. To address this issue, we performed a systematic analysis of fusion protein transcriptional targets. We expressed AML1/ETO, PML/RAR, and PLZF/RAR in U937 hemopoietic precursor cells and measured global gene expression using oligonucleotide chips. We identified 1,555 genes regulated concordantly by at least two fusion proteins that were further validated in patient samples and finally classified according to available functional information. Strikingly, we found that AML fusion proteins induce genes involved in the maintenance of the stem cell phenotype and repress DNA repair genes, mainly of the base excision repair pathway. Functional studies confirmed that ectopic expression of fusion proteins constitutively activates pathways leading to increased stem cell renewal (e.g., the Jagged1/Notch pathway) and provokes accumulation of DNA damage. We propose that expansion of the stem cell compartment and induction of a mutator phenotype are relevant features underlying the leukemic potential of AML-associated fusion proteins. PMID:14660751

  1. Leukemia

    MedlinePlus

    ... a combination of genetic and environmental factors. How leukemia forms In general, leukemia is thought to occur ... causing the signs and symptoms of leukemia. How leukemia is classified Doctors classify leukemia based on its ...

  2. Leukemia

    MedlinePlus

    ... version of this page please turn Javascript on. Leukemia What Is Leukemia? Leukemia is a cancer of the blood cells. ... diagnosed with leukemia are over 50 years old. Leukemia Starts in Bone Marrow Click for more information ...

  3. Autophagy: friend or foe in the treatment of fusion protein-associated leukemias?

    PubMed

    Torgersen, Maria Lyngaas; Simonsen, Anne

    2013-12-01

    Both radiation and chemotherapeutic drugs induce autophagy in tumor cells, and whether this contributes to cell death or survival is debated. Although a prodeath role has been reported in certain contexts, treatment-induced autophagy often exerts a prosurvival function by preventing apoptosis and delaying necrosis. Interestingly, a more specific role of autophagy has been demonstrated in certain subtypes of leukemia. The fusion oncoproteins PML-RARA and BCR-ABL, the main oncogenic drivers of acute promyelocytic leukemia and chronic myeloid leukemia (CML), respectively, have recently been identified as autophagy substrates and their degradation by autophagy shown to contribute to treatment. However, this does not seem to be a general feature of leukemic fusion oncoproteins, as we recently found that AML1-ETO, the most frequently occurring acute myeloid leukemia (AML) fusion protein, is not an autophagy substrate. Rather we demonstrate a clear prosurvival role of autophagy in this AML subtype and that addition of autophagy inhibitors in the treatment regimen might be beneficial.

  4. Fetal origins of the TEL-AML1 fusion gene in identical twins with leukemia

    PubMed Central

    Ford, Anthony M.; Bennett, Caroline A.; Price, Cathy M.; Bruin, M. C. A.; Van Wering, Elisabeth R.; Greaves, Mel

    1998-01-01

    The TEL (ETV6)−AML1 (CBFA2) gene fusion is the most common reciprocal chromosomal rearrangement in childhood cancer occurring in ≈25% of the most predominant subtype of leukemia— common acute lymphoblastic leukemia. The TEL-AML1 genomic sequence has been characterized in a pair of monozygotic twins diagnosed at ages 3 years, 6 months and 4 years, 10 months with common acute lymphoblastic leukemia. The twin leukemic DNA shared the same unique (or clonotypic) but nonconstitutive TEL-AML1 fusion sequence. The most plausible explanation for this finding is a single cell origin of the TEL-AML fusion in one fetus in utero, probably as a leukemia-initiating mutation, followed by intraplacental metastasis of clonal progeny to the other twin. Clonal identity is further supported by the finding that the leukemic cells in the two twins shared an identical rearranged IGH allele. These data have implications for the etiology and natural history of childhood leukemia. PMID:9539781

  5. JAK inhibitors suppress t(8;21) fusion protein-induced leukemia

    PubMed Central

    Lo, Miao-Chia; Peterson, Luke F.; Yan, Ming; Cong, Xiuli; Hickman, Justin H.; DeKelver, Russel C.; Niewerth, Denise; Zhang, Dong-Er

    2014-01-01

    Oncogenic mutations in components of the JAK/STAT pathway, including those in cytokine receptors and JAKs, lead to increased activity of downstream signaling and are frequently found in leukemia and other hematological disorders. Thus, small-molecule inhibitors of this pathway have been the focus of targeted therapy in these hematological diseases. We previously showed that t(8;21) fusion protein AML1-ETO and its alternatively spliced variant AML1-ETO9a (AE9a) enhance the JAK/STAT pathway via down-regulation of CD45, a negative regulator of this pathway. To investigate the therapeutic potential of targeting JAK/STAT in t(8;21) leukemia, we examined the effects of a JAK2-selective inhibitor TG101209 and a JAK1/2-selective inhibitor INCB18424 on t(8;21) leukemia cells. TG101209 and INCB18424 inhibited proliferation and promoted apoptosis of these cells. Furthermore, TG101209 treatment in AE9a leukemia mice reduced tumor burden and significantly prolonged survival. TG101209 also significantly impaired the leukemia-initiating potential of AE9a leukemia cells in secondary recipient mice. These results demonstrate the potential therapeutic efficacy of JAK inhibitors in treating t(8;21) AML. PMID:23812420

  6. RANBP2-ALK fusion combined with monosomy 7 in acute myelomonocytic leukemia.

    PubMed

    Lim, Ji-Hun; Jang, Seongsoo; Park, Chan-Jeoung; Cho, Young-Uk; Lee, Je-Hwan; Lee, Kyoo-Hyung; Lee, Jin-Ok; Shin, Jong-Yeon; Kim, Jong-Il; Huh, Jooryung; Seo, Eul-Ju

    2014-01-01

    Anaplastic lymphoma receptor tyrosine kinase (ALK) is located on chromosome 2p23; the chromosomal rearrangements of this gene are common genetic alterations, resulting in the creation of multiple fusion genes involved in tumorigenesis. However, the presence of an ALK fusion in myeloid malignancies is extremely rare. We report a case of acute myelomonocytic leukemia in a 31-year-old woman with an unusual rearrangement between RAN-binding protein 2 (RANBP2) and ALK and a karyotype of 45,XX,inv(2)(p23q21),-7[20]. We detected an ALK rearrangement using fluorescence in situ hybridization, identified the ALK fusion partner by using RNA transcriptome sequencing, and demonstrated the RANBP2-ALK fusion transcript by reverse transcriptase--PCR and Sanger sequencing. Immunohistochemistry for ALK showed strong staining of the nuclear membrane in leukemic cells. The patient had an unfavorable clinical course. Our results, together with a literature review, suggest the RANBP2-ALK fusion combined with monosomy 7 may be related to a unique clonal hematologic disorder of childhood and adolescence, characterized by myelomonocytic leukemia and a poor prognosis. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. A novel fusion of RBM6 to CSF1R in acute megakaryoblastic leukemia.

    PubMed

    Gu, Ting-lei; Mercher, Thomas; Tyner, Jeffrey W; Goss, Valerie L; Walters, Denise K; Cornejo, Melanie G; Reeves, Cynthia; Popova, Lana; Lee, Kimberly; Heinrich, Michael C; Rush, John; Daibata, Masanori; Miyoshi, Isao; Gilliland, D Gary; Druker, Brian J; Polakiewicz, Roberto D

    2007-07-01

    Activated tyrosine kinases have been frequently implicated in the pathogenesis of cancer, including acute myeloid leukemia (AML), and are validated targets for therapeutic intervention with small-molecule kinase inhibitors. To identify novel activated tyrosine kinases in AML, we used a discovery platform consisting of immunoaffinity profiling coupled to mass spectrometry that identifies large numbers of tyrosine-phosphorylated proteins, including active kinases. This method revealed the presence of an activated colony-stimulating factor 1 receptor (CSF1R) kinase in the acute megakaryoblastic leukemia (AMKL) cell line MKPL-1. Further studies using siRNA and a small-molecule inhibitor showed that CSF1R is essential for the growth and survival of MKPL-1 cells. DNA sequence analysis of cDNA generated by 5'RACE from CSF1R coding sequences identified a novel fusion of the RNA binding motif 6 (RBM6) gene to CSF1R gene generated presumably by a t(3;5)(p21;q33) translocation. Expression of the RBM6-CSF1R fusion protein conferred interleukin-3 (IL-3)-independent growth in BaF3 cells, and induces a myeloid proliferative disease (MPD) with features of megakaryoblastic leukemia in a murine transplant model. These findings identify a novel potential therapeutic target in leukemogenesis, and demonstrate the utility of phosphoproteomic strategies for discovery of tyrosine kinase alleles.

  8. Heterogeneity of genomic fusion of BCR and ABL in Philadelphia chromosome-positive acute lymphoblastic leukemia

    SciTech Connect

    Rubin, C.M.; Carrino, J.J.; Dickler, M.N.; Leibowitz, D.; Smith, S.D.; Westbrook, C.A.

    1988-04-01

    Philadelphia chromosome-positive acute lymphoblastic leukemia occurs in two molecular forms, those with and those without rearrangement of the breakpoint cluster region on chromosome 22. The molecular abnormality in the former group is similar to that found in chronic myelogenous leukemia. To characterize the abnormality in the breakpoint cluster region-unrearranged form, the authors have mapped a 9; 22 translocation from the Philadelphia chromosome-positive acute lymphoblastic leukemia cell line SUP-B13 by using pulsed-field gel electrophoresis and have cloned the DNA at the translocation junctions. They demonstrate a BCR-ABL fusion gene on the Philadelphia chromosome. The exons from ABL are the same. Analysis of leukemic cells from four other patients with breakpoint cluster region-unrearranged Philadelphia chromosome-positive acute lymphoblastic leukemia revealed a rearrangement on chromosome 22 close to the breakpoint in SUP-B13 in only one patient. These data indicate that breakpoints do not cluster tightly in this region but are scattered, possibly in a large intron. Given the large size of BCR and the heterogeneity in breakpoint location, detection of BCR rearrangement by standard Southern blot analysis is difficult. Pulsed-field gel electrophoresis should allow detection at the DNA level in every patient and thus will permit clinical correlation of the breakpoint location with prognosis.

  9. Frequency of rare BCR-ABL1 fusion transcripts in chronic myeloid leukemia patients.

    PubMed

    Arun, A K; Senthamizhselvi, A; Mani, S; Vinodhini, K; Janet, N B; Lakshmi, K M; Abraham, A; George, B; Srivastava, A; Srivastava, V M; Mathews, V; Balasubramanian, P

    2017-06-01

    The hallmark of chronic myeloid leukemia (CML) is the presence of Philadelphia chromosome, its resultant fusion transcript (BCR-ABL1), and fusion protein (p210). Alternate breakpoints in BCR (m-bcr, μ-bcr, and others) or ABL1 result in the expression of few rare fusion transcripts (e19a2, e1a2, e13a3, e14a3) and fusion proteins (p190, p200, p225) whose exact clinical significance remains to be determined. Our study was designed to determine the type and frequency of BCR-ABL1 fusion transcripts in 1260 CML patients and to analyze the prognosis and treatment response in patients harboring rare BCR-ABL1 fusion transcripts. The frequency of various BCR-ABL1 fusion transcripts was as follows: e14a2 (60%), e13a2 (34.3%), e1a2 (1.2%), e1a2 + e13a2 (2.0%), e1a2 + e14a2 (1.8%), e19a2 (0.3%), and e14a3 (0.3%). CML patients with e1a2 transcripts had higher rates of disease progression, resistance, or suboptimal response to imatinib and failed to achieve major molecular response. Characterization of the specific fusion transcript in CML patients is important owing to the difference in prognosis and response to therapy in addition to the conventional need for monitoring treatment response. CML patients with e1a2 transcripts have to be closely monitored due to the high incidence of disease progression and treatment resistance/failure. © 2016 John Wiley & Sons Ltd.

  10. The eleven-nineteen-leukemia protein ENL connects nuclear MLL fusion partners with chromatin.

    PubMed

    Zeisig, Deniz T; Bittner, Claudia B; Zeisig, Bernd B; García-Cuéllar, Maria-Paz; Hess, Jay L; Slany, Robert K

    2005-08-18

    Mixed lineage leukemia (MLL) fusion proteins are derived from translocations at 11q23 that occur in aggressive subtypes of leukemia. As a consequence, MLL is joined to different unrelated proteins to form oncogenic transcription factors. Here we demonstrate a direct interaction between several nuclear MLL fusion partners and present evidence for a role of these proteins in histone binding. In two-hybrid studies, ENL interacted with AF4 and AF5q31 as well as with a fragment of AF10. A structure-function analysis revealed that the AF4/AF5q31/AF10 binding domain in ENL coincided with the C-terminus that is essential for transformation by MLL-ENL. The ENL/AF4 association was corroborated by GST-pulldown experiments and by mutual coprecipitation. Both proteins colocalized in vivo in a nuclear speckled pattern. Moreover, AF4 and ENL coeluted on sizing columns together with the known ENL binding partner Polycomb3, suggesting the presence of a multiprotein complex. The overexpression of ENL alone activated a reporter construct and a mutational screen indicated the conserved YEATS domain as essential for this function. Overlay and pulldown-assays finally showed a specific and YEATS domain-dependent association of ENL with histones H3 and H1. In summary, our studies support a common role for nuclear MLL fusion partners in chromatin biology.

  11. Characterization of pal-1, a common proviral insertion site in murine leukemia virus-induced lymphomas of c-myc and Pim-1 transgenic mice.

    PubMed Central

    Scheijen, B; Jonkers, J; Acton, D; Berns, A

    1997-01-01

    Insertional mutagenesis with Moloney murine leukemia virus (MoMLV) in c-myc and Pim-1 transgenic mice permits the identification of oncogenes that collaborate with the transgenes in lymphomagenesis. The recently identified common insertion site pal-1, in MoMLV-induced lymphomas, is located in a region in which several independent integration clusters are found: eis-1, gfi-1, and evi-5. Proviral insertions of MoMLV in the different integration clusters upregulate the transcriptional activity of the Gfi-1 gene, which is located within the pal-1 locus. The eis-1/pal-1/gfi-1/evi-5 locus serves as a target for MoMLV proviral insertions in pre-B-cell lymphomas of Emu-myc transgenic mice (20%) and in T-cell lymphomas of H-2K-myc (75%) and Emu-pim-1 (93%) transgenic mice. Many tumors overexpress both Gfi-1 as well as Myc and Pim gene family members, indicating that Gfi-1 collaborates with Myc and Pim in lymphomagenesis. Proviral integrations in the previously identified insertion site bmi-1 are, however, mutually exclusive with integrations in the eis-1/pal-1/gfi-1/evi-5 locus. This finding suggests that Bmi-1 and Gfi-1 belong to the same complementation group in lymphoid transformation. PMID:8985317

  12. Establishment and genetic characterization of a novel mixed-phenotype acute leukemia cell line with EP300-ZNF384 fusion.

    PubMed

    Ping, Nana; Qiu, Huiying; Wang, Qian; Dai, Haiping; Ruan, Changgeng; Ehrentraut, Stefan; Drexler, Hans G; MacLeod, Roderick A F; Chen, Suning

    2015-08-21

    Herein, we describe the establishment and characterization of the first mixed-phenotype acute leukemia cell line (JIH-5). The JIH-5 cell line was established from leukemia cells with B lymphoid/myeloid phenotype from a female mixed-phenotype acute leukemia patient. JIH-5 cells exhibit an immunophenotype comprised of myeloid and B lymphoid antigens. Whole-exome sequencing revealed somatic mutations in nine genes in JIH-5 cells. Transcriptional sequencing of JIH-5 cells identified EP300-ZNF384 fusion transcript, which is a recurrent alteration in B cell acute lymphoblastic leukemia. Our results suggest that the JIH-5 cell line may serve as a tool for the study of mixed-phenotype acute leukemia or EP300-ZNF384.

  13. Analysis of acute leukemias with MLL/ENL fusion transcripts: identification of two novel breakpoints in ENL.

    PubMed

    Fu, Jen-Fen; Liang, Der-Cherng; Shih, Lee-Yung

    2007-01-01

    t(11;19)(q23;p13.3); is one of the common chromosomal translocations in acute leukemias involving MLL rearrangements. This translocation generates MLL/ENL fusion transcripts. In a study of acute leukemias, 148 patients were identified to have MLL rearrangements by Southern blot analysis. Reverse transcriptase-polymerase chain reaction (RT-PCR) assay, using primer sets covering the 2 previously described breakpoints at exons 2 and 7 of ENL detected 11 samples harboring MLL/ENL. complementary DNA panhandle PCR further identified 4 additional cases with novel breakpoints in ENL at exon 4 or 6. Sequencing analysis showed that all novel fusion transcripts were in-frame. The conventional cytogenetic analysis failed to detect t(11;19) in 6 of 13 cases. Of 15 patients with MLL/ENL, 7 had precursor B-cell acute lymphoblastic leukemia, 4 had T-cell acute lymphoblastic leukemia, and 4 had acute myeloid leukemia. The present study showed that PCR-based techniques are more sensitive than conventional karyotyping for detecting MLL/ENL fusions and an extra antisense primer at exon 6 of ENL should be included in RT-PCR assay to ensure complete detection of all MLL/ENL fusion transcripts.

  14. Ph-like acute lymphoblastic leukemia with a novel PAX5-KIDINS220 fusion transcript.

    PubMed

    Sakamoto, Kenichi; Imamura, Toshihiko; Kanayama, Takuyo; Yano, Mio; Asai, Daisuke; Deguchi, Takao; Hashii, Yoshiko; Tanizawa, Akihiko; Ohshima, Yusei; Kiyokawa, Nobutaka; Horibe, Keizo; Sato, Atsushi

    2017-04-01

    Although "paired box 5" (PAX5)-related fusion genes are well documented in childhood B-cell precursor acute lymphoblastic leukemia (ALL), these types of fusion with the exception of PAX5-JAK2 are rarely seen in patients with gene expression profiles similar to those of BCR-ABL1 (Philadelphia)-positive ALL (Ph-like ALL). We report a novel fusion of the genes PAX5 and "kinase D-interacting substrate of 220 kDa" (KIDINS220, also known as ARMS) in a Ph-like ALL. As PAX5 is a master regulator of B-lymphocyte differentiation, PAX5 rearrangements induce a differentiation block in B lymphocytes. KIDINS220 is a mediator of multiple receptor signaling pathways, interacts with both T- and B-cell receptors, and is necessary for sustained extracellular signal-regulated kinase (ERK) signaling. Although functional studies are needed, the PAX5-KIDINS220 fusion protein might not only inhibit wild-type PAX5 function, but also promote sustained activation of the ERK signaling pathway through upregulation of KIDINS220. © 2016 Wiley Periodicals, Inc.

  15. Ovine MHC class II DRB1 alleles associated with resistance or susceptibility to development of bovine leukemia virus-induced ovine lymphoma.

    PubMed

    Nagaoka, Y; Kabeya, H; Onuma, M; Kasai, N; Okada, K; Aida, Y

    1999-02-15

    For the further characterization of bovine leukemia virus (BLV)-induced leukemogenesis, we investigated the association between polymorphism of ovine leukocyte antigen (OLA)-DRB1 gene and tumor development after infection of sheep with BLV. We infected 28 sheep with BLV and cloned exon 2 of the OLA-DRB1 gene from asymptomatic animals and from animals with lymphoma Sequence analysis revealed that, among 12 healthy sheep without any evidence of tumor, ten (83.3%) carried DRB1 alleles encoding Arg-Lys (RK) at positions beta70/71 as compared with only 6 (37.5%) of the 16 sheep with lymphoma, which suggested that alleles encoding the RK motif might protect against development of tumors after infection by BLV. By contrast, alleles encoding Ser-Arg (SR) at positions beta70/71 were present at a significantly elevated frequency in sheep with lymphoma as compared with the healthy carriers, which indicated that OLA-DRB1 alleles encoding the SR motif might be positively related to susceptibility to tumor development. The two amino acids in these motifs line a pocket that accommodates the side chain of a bound peptide according to a model of the crystal structure of human leukocyte antigen (HLA)-DR1. To analyze immunoreactions of sheep with alleles that encoded RK or SR at beta70/71, we selected sheep with either the RK/SR genotypes or the SR/SR genotypes and immunized them with a mixture of multiple synthetic antigenic peptides that corresponded to T-helper, T-cytotoxic, and B-cell epitopes of the BLV envelope glycoprotein gp51. Two weeks after the last immunization, all of the sheep were challenged with BLV. Sheep with the RK/SR genotype produced neutralizing antibodies against BLV; they eliminated BLV completely within 28 weeks of the BLV challenge, and they gave strong lymphocyte-proliferative responses to the peptides used for immunization. Moreover, such animals did not develop lymphoma. By contrast, sheep with the SR/SR genotype continued to produce BLV throughout the

  16. Efficient detection of leukemia-related fusion transcripts by multiplex PCR applied on a microelectronic platform.

    PubMed

    Corradi, B; Fazio, G; Palmi, C; Rossi, V; Biondi, A; Cazzaniga, G

    2008-02-01

    The identification of prognostically relevant fusion genes is required in the routine diagnostic process of most advanced clinical protocols for leukemia patients, either for risk stratification, target-specific treatments, and/or as markers for monitoring Minimal Residual Disease during treatment. However, there is emerging need to implement diagnostics and patient classification based on other biological features, such as expression levels of specific genes or genomic polymorphisms and/or mutations. This advancement would ideally be pursued in a diagnostic laboratory by an unique platform capable of different diagnostic purposes. We developed a rapid, accurate and reproducible assay to screen for the most common fusion gene transcripts in human leukemia, which combines a multiplex RT-PCR approach with the electronic hybridization and fluorescent detection on the Nanogen NanoChip Molecular Biology Workstation. This study demonstrates, as a proof-of-principle, that this microelectronic device, highly effective in detecting single base mutations, is also efficient in the analysis of gene expression, thus providing as a multi-purpose platform for relevant comprehensive diagnostics of hemato-oncology patients.

  17. Leukemia

    MedlinePlus

    Leukemia is cancer of the white blood cells. White blood cells help your body fight infection. Your blood cells form in your bone marrow. In leukemia, the bone marrow produces abnormal white blood cells. ...

  18. TEL/AML-1 fusion gene. its frequency and prognostic significance in childhood acute lymphoblastic leukemia.

    PubMed

    Jamil, A; Theil, K S; Kahwash, S; Ruymann, F B; Klopfenstein, K J

    2000-10-15

    TEL gene rearrangement due to the 12;21 chromosome translocation is believed to be the most common molecular genetic abnormality in childhood acute lymphoblastic leukemia (ALL). A study was conducted to investigate the frequency and prognostic significance of TEL/AML-1 fusion gene resulting from a cryptic t(12;21)(p13;q22). Bone marrow samples from 86 patients diagnosed over the past 5 years at Columbus Children's Hospital were analyzed by fluorescence in situ hybridization (FISH) technique for TEL/AML-1 fusion gene, using LSI((R)) DNA probes. The positive cases were analyzed for clinical outcome. Patients in this study received treatment according to Children's Cancer Group (CCG) protocols. Fifteen of the 86 cases (17%) were positive for the fusion gene. All were B-cell lineage and except for one, all were CD10 positive. TEL/AML-1 was not found in any T-cell ALL. The mean overall survival (OS) following diagnosis for the TEL/AML-1-positive group was significantly longer than for the TEL/AML-1-negative group by log-rank = 7.84, P = 0.005. Similarly, the event-free survival (EFS) after remission for the positive group (median 94.5 months) was longer than the negative group (median 57 months) by log-rank = 7.19, P = 0.007. This study confirms that the TEL/AML-1 fusion gene may be the most common genetic event in childhood ALL, occurring in 17% of the patients. It appears restricted to the B-cell lineage. In this study, the presence of a TEL/AML-1 fusion gene was statistically significant in predicting both OS and EFS, indicating a favorable clinical outcome for these patients. Screening for TEL/AML-1 should become routine at diagnosis and a useful biological variable for risk stratification in future clinical trials.

  19. Prevalence of Abelson murine leukemia viral oncogene homolog-breakpoint cluster region fusions and correlation with peripheral blood parameters in chronic myelogenous leukemia patients in Lorestan Province, Iran

    PubMed Central

    Kiani, Ali Asghar; Shahsavar, Farhad; Gorji, Mojtaba; Ahmadi, Kolsoum; Nazarabad, Vahideh Heydari; Bahmani, Banafsheh

    2016-01-01

    Context: Chronic myelogenous leukemia (CML) is a chronic malignancy of myeloid linage associated with a significant increase in granulocytes in bone marrow and peripheral blood. CML diagnosis is based on detection of Philadelphia chromosome and “Abelson murine leukemia viral oncogene homolog” (ABL)-“breakpoint cluster region protein” fusions (ABL-BCR fusions). Aims: In this study, patients with CML morphology were studied according to ABL-BCR fusions and the relationship between the fusions and peripheral blood cell changes was examined. Materials and Methods: All patients suspected to chronic myeloproliferative disorders in Lorestan Province visiting subspecialist hematology clinics who were confirmed by oncologist were studied over a period of 5 years. After completing basic data questionnaire, blood samples were obtained with informed consent from the patients. Blood cell count and morphology were investigated and RNA was extracted from blood samples. cDNA was synthesized from RNA and ABL-BCR fusions including b3a2 and b2a2 (protein 210 kd or p210), e1a2 (protein 190 kdor p190), and e19a2 (protein 230 kdor p230) were studied by multiplex reverse transcription polymerase chain reaction method. Coexistence of e1a2 and b2a2 (p210/p190) fusions was also studied. The prevalence of mutations and their correlation with the blood parameters were statistically analyzed. Results: Of 58 patients positive for ABL-BCR fusion, 18 (30.5%) had b2a2 fusion, 37 (62.71%) had b3a2 fusion and three (3.08%) had e1a2 fusion. Coexistence of e1a2 and b2a2 (p210/p190) was not observed. There was no significant correlation between ABL-BCR fusions and white blood cell count, platelet count, and hemoglobin concentration. Conclusions: The ABL-BCR fusions in Lorestan Province were similar to other studies in Iran, and b3a2 fusion had the highest prevalence in the studied patients studied. PMID:27857896

  20. PML-RARalpha fusion gene transcripts and biological features in acute promyelocytic leukemia patients.

    PubMed

    Melo, R A M; de Vasconcellos, J F; Melo, F C B C; Machado, C G F; Lacerda, T M S; Souto, F R

    2006-04-01

    Acute promyelocytic leukemia (APL) is characterized by the presence of rearrangements involving the retinoic acid receptor alpha (RARalpha) gene and a variable incidence in different populations. The hybrid gene PML-RARalpha, present in 98% of cases, encodes a fusion protein essential to the pathogenesis of the disease. Depending of the PML's gene breakpoint in chromosome 15, the transcript subtypes bcr1, bcr2 and bcr3 may be formed. The correlation between these transcript subtypes and clinical parameters is still controversial. The objective of this study was to determine the frequencies of the PML-RARalpha transcripts and subtypes in a series of 32 APL patients from Northeast Brazil and to evaluate the association of these subtypes to different parameters. The method used was RT-PCR. The frequency of our APL cases is approximately 28% of the acute leukemias. The results showed the presence of PML-RARalpha isoform in all patients and a higher frequency of the bcr1/2 subtype. No significant statistical association was found between molecular subtypes and age, sex, French-American-British (FAB) classification, leukocyte and platelet count, hemoglobin level or coagulation tests. In conclusion, these data suggest similar molecular and biological features for our APL patients at diagnosis in comparison with those reported in current scientific literature.

  1. Cytoplasmic calcium increase via fusion with inactivated Sendai virus induces apoptosis in human multiple myeloma cells by downregulation of c-Myc oncogene

    PubMed Central

    Jiang, Yingzhe; Saga, Kotaro; Miyamoto, Yasuhide; Kaneda, Yasufumi

    2016-01-01

    Because the emergence of drug resistance is a major limitation of current treatments for multiple myeloma (MM), it is necessary to continuously develop novel anticancer strategies. Here, using an inactivated Sendai virus (Hemagglutinating Virus of Japan; HVJ) envelope (HVJ-E), we discovered that increase of cytoplasmic Ca2+ by virus-cell fusion significantly induced apoptosis against human MM cells but not peripheral blood mononuclear cells from healthy donors. Interaction of F protein of HVJ-E with MM cells increased intracellular Ca2+ level of MMs by the induction of Ca2+ efflux from endoplasmic reticulum but not influx from extracellular region. The elevation of the Ca2+ cytoplasmic level induced SMAD1/5/8 phosphorylation and translocation into the nucleus, and SMAD1/5/8 and SMAD4 complex suppressed c-Myc transcription. Meanwhile, HVJ-E decreases S62 phosphorylation of c-Myc and promotes c-Myc protein degradation. Thus, HVJ-E-induced cell death of MM resulted from suppression of c-Myc by both destabilization of c-Myc protein and downregulation of c-Myc transcription. This study indicates that HVJ-E will be a promising tool for MM therapy. PMID:27145280

  2. Treatment of acute lymphoblastic leukemia with an rGel/BLyS fusion toxin

    PubMed Central

    Parameswaran, Reshmi; Yu, Min; Lyu, Mi-Ae; Lim, Min; Rosenblum, Michael G.; Groffen, John; Heisterkamp, Nora

    2012-01-01

    Acute lymphoblastic leukemia (ALL) is the most common malignancy affecting children and a major cause of mortality from hematopoietic malignancies in adults. A substantial number of patients become drug resistant during chemotherapy, necessitating the development of alternative modes of treatment. rGel/BLyS is a toxin-cytokine fusion protein used for selective killing of malignant B-cells expressing receptors for B-cell Activating Factor (BAFF/BLyS) by receptor-targeted delivery of the toxin, Gelonin. Here we demonstrate that rGel/BLyS binds to ALL cells expressing BAFF receptor (BAFF-R) and upon internalization, it induces apoptosis of these cells and causes down-regulation of survival genes even in the presence of stromal protection. Using an immunodeficient transplant model for human ALL, we show that rGel/BLyS prolongs survival of both Philadelphia chromosome-positive and negative ALL-bearing mice. Furthermore, we used AMD3100, a CXCR4 antagonist, to mobilize the leukemic cells protected in the bone marrow microenvironment and the combination with rGel/BLyS resulted in a significant reduction of the tumor load in the bone marrow and complete eradication of ALL cells from the circulation. Thus, a combination treatment with the B-cell-specific fusion toxin rGel/BLyS and the mobilizing agent AMD3100 could be an effective alternative approach to chemotherapy for the treatment of primary and relapsed ALL. PMID:22373785

  3. Expression pattern of the RAR alpha-PML fusion gene in acute promyelocytic leukemia.

    PubMed Central

    Alcalay, M; Zangrilli, D; Fagioli, M; Pandolfi, P P; Mencarelli, A; Lo Coco, F; Biondi, A; Grignani, F; Pelicci, P G

    1992-01-01

    Two chimeric genes, PML-RAR alpha and RAR alpha-PML, are formed as a consequence of the acute promyelocytic leukemia (APL)-specific reciprocal translocation of chromosomes 15 and 17 [t(15;17)]. PML-RAR alpha is expressed as a fusion protein. We investigated the organization and expression pattern of the RAR alpha-PML gene in a series of APL patients representative of the molecular heterogeneity of the t(15;17) and found (i) two types of RAR alpha-PML mRNA junctions (RAR alpha exon 2/PML exon 4 or RAR alpha exon 2/PML exon 7) that maintain the RAR alpha and PML longest open reading frames aligned and are the result of chromosome 15 breaking at two different sites; and (ii) 10 different RAR alpha-PML fusion transcripts that differ for the assembly of their PML coding exons. A RAR alpha-PML transcript was present in most, but not all, APL patients. Images PMID:1317574

  4. A suicidal DNA vaccine expressing the fusion protein of peste des petits ruminants virus induces both humoral and cell-mediated immune responses in mice.

    PubMed

    Wang, Yong; Yue, Xiaolin; Jin, Hongyan; Liu, Guangqing; Pan, Ling; Wang, Guijun; Guo, Hao; Li, Gang; Li, Yongdong

    2015-12-01

    Peste des petits ruminants (PPR), a highly contagious disease induced by PPR virus (PPRV), affects sheep and goats. PPRV fusion (F) protein is important for the induction of immune responses against PPRV. We constructed a Semliki Forest virus (SFV) replicon-vectored DNA vaccine ("suicidal DNA vaccine") and evaluated its immunogenicity in BALB/c mice. The F gene of PPRV was cloned and inserted into the SFV replicon-based vector pSCA1. The antigenicity of the resultant plasmid pSCA1/F was identified by indirect immunofluorescence and western blotting. BALB/c mice were then intramuscularly injected with pSCA1/F three times at 14-d intervals. Specific antibodies and virus-neutralizing antibodies against PPRV were quantified by indirect ELISA and microneutralization tests, respectively. Cell-mediated immune responses were examined by cytokine and lymphocyte proliferation assays. The pSCA1/F expressed F protein in vitro and induced specific and neutralizing antibody production, and lymphocyte proliferation in mice. Mice vaccinated with pSCA1/F had increased IL-2 and IL-10 levels after 24-h post first immunization. IFN-γ and TNF-α levels increased from that time point and gradually decreased thereafter. Thus, the Semliki Forest virus replicon-vectored DNA vaccine expressing the F protein of PPRV induced both humoral and cell-mediated immune responses in mice. This could be considered as a novel strategy for vaccine development against PPR. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Targeting binding partners of the CBFβ-SMMHC fusion protein for the treatment of inversion 16 acute myeloid leukemia

    PubMed Central

    Hyde, R. Katherine

    2016-01-01

    Inversion of chromosome 16 (inv(16)) generates the CBFβ-SMMHC fusion protein and is found in nearly all patients with acute myeloid leukemia subtype M4 with Eosinophilia (M4Eo). Expression of CBFβ-SMMHC is causative for leukemia development, but the molecular mechanisms underlying its activity are unclear. Recently, there have been important advances in defining the role of CBFβ-SMMHC and its binding partners, the transcription factor RUNX1 and the histone deacetylase HDAC8. Importantly, initial trials demonstrate that small molecules targeting these binding partners are effective against CBFβ-SMMHC induced leukemia. This review will discuss recent advances in defining the mechanism of CBFβ-SMMHC activity, as well as efforts to develop new therapies for inv(16) AML. PMID:27542261

  6. Identification of ins(8;21) with AML1/ETO fusion in acute myelogenous leukemia M2 by molecular cytogenetics.

    PubMed

    Urioste, M; Martínez-Ramírez, A; Cigudosa, J C; Mateo, M S; Martínez, P; Contra, T; Benítez, J

    2002-02-01

    A high percentage of cases of acute myelogenous leukemia (AML) of the M2 subtype show a rearrangement between the AML1 and ETO genes. The detection of the AML1/ETO fusion has clinical relevance because patients with this subtype have a good prognosis. We present the results of conventional and molecular cytogenetic studies in a patient with acute myelogenous leukemia French-American-British M2 classification, who had a complex karyotype involving chromosomes 8 and 21. Dual-color fluorescence in situ hybridization (FISH) using the AML1/ETO probe demonstrated a recombination of both genes on an add(8) chromosome. The use of other FISH probes (CEP8, c-myc and TEL21) and spectral karyotyping indicated that AML1/ETO fusion occurred as a consequence of a previously undescribed ins(8;21)(q22;q22.1q22.3).

  7. Clinical Courses of Two Pediatric Patients with Acute Megakaryoblastic Leukemia Harboring the CBFA2T3-GLIS2 Fusion Gene

    PubMed Central

    Ishibashi, Mayu; Yokosuka, Tomoko; Yanagimachi, Masakatsu D.; Iwasaki, Fuminori; Tsujimoto, Shin-ichi; Sasaki, Koji; Takeuchi, Masanobu; Tanoshima, Reo; Kato, Hiromi; Kajiwara, Ryosuke; Tanaka, Fumiko; Goto, Hiroaki; Yokota, Shumpei

    2016-01-01

    Acute megakaryoblastic leukemia (AMKL) in children without Down syndrome (DS) has an extremely poor outcome with 3-year survival of less than 40%, whereas AMKL in children with DS has an excellent survival rate. Recently, a novel recurrent translocation involving CBFA2T3 and GLIS2 was identified in about 30% of children with non-DS AMKL, and the fusion gene was reported as a strong poor prognostic factor in pediatric AMKL. We report the difficult clinical courses of pediatric patients with AMKL harboring the CBFA2T3-GLIS2 fusion gene. PMID:27094503

  8. Simultaneous detection of 45 fusion genes in leukemia by dual-color fluorescence real-time PCR.

    PubMed

    Zheng, Z; Zhang, P; He, G; Liao, K; Wang, Z; Pan, J; Du, K; Du, J; Li, B-A

    2017-04-01

    Detection of recurrent genetic abnormalities is of great significance for a refined diagnosis and assessment of prognosis in leukemia. Conventional nested reverse transcription PCR is labor intensive and time-consuming. We have developed a novel dual-color TaqMan probe-based real-time PCR method for the simultaneous screening of 45 fusion transcripts in 12 parallel reactions. The method was tested and validated with cell lines carrying known fusion transcripts and patient samples. A multiplex real-time PCR method was successfully developed for rapid detection of 45 fusion genes and validated for 15 of the more commonly detected fusion genes. Intra-assay reproducibility assessed for the most frequent rearrangements ranged from 0.41% to 0.74% for the coefficient of variation (CV) of cycle threshold (Ct) and the interassay reproducibility ranged from 1.62% to 2.83% in five separate experiments. The lowest detection limit for the translocations tested ranged between 1 : 16 000 and 1 : 32 000. Validation of the method with 213 patient samples showed 100% specificity and excellent consistence with conventional nested RT-PCR. Overall, we believe that this method is easily applicable, cost-effective, and clinically useful for a rapid screening of fusion genes in the initial diagnostic phase of leukemia. Its use can also be extended to the monitoring of minimal residual disease. © 2017 John Wiley & Sons Ltd.

  9. Flow Cytometric Measurement of Blood Cells with BCR-ABL1 Fusion Protein in Chronic Myeloid Leukemia.

    PubMed

    Löf, Liza; Arngården, Linda; Olsson-Strömberg, Ulla; Siart, Benjamin; Jansson, Mattias; Dahlin, Joakim S; Thörn, Ingrid; Christiansson, Lisa; Hermansson, Monica; Larsson, Anders; Ahlstrand, Erik; Wålinder, Göran; Söderberg, Ola; Rosenquist, Richard; Landegren, Ulf; Kamali-Moghaddam, Masood

    2017-04-04

    Chronic myeloid leukemia (CML) is characterized in the majority of cases by a t(9;22)(q34;q11) translocation, also called the Philadelphia chromosome, giving rise to the BCR-ABL1 fusion protein. Current treatment with tyrosine kinase inhibitors is directed against the constitutively active ABL1 domain of the fusion protein, and minimal residual disease (MRD) after therapy is monitored by real-time quantitative PCR (RQ-PCR) of the fusion transcript. Here, we describe a novel approach to detect and enumerate cells positive for the BCR-ABL1 fusion protein by combining the in situ proximity ligation assay with flow cytometry as readout (PLA-flow). By targeting of the BCR and ABL1 parts of the fusion protein with one antibody each, and creating strong fluorescent signals through rolling circle amplification, PLA-flow allowed sensitive detection of cells positive for the BCR-ABL1 fusion at frequencies as low as one in 10,000. Importantly, the flow cytometric results correlated strongly to those of RQ-PCR, both in diagnostic testing and for MRD measurements over time. In summary, we believe this flow cytometry-based method can serve as an attractive approach for routine measurement of cells harboring BCR-ABL1 fusions, also allowing simultaneously assessment of other cell surface markers as well as sensitive longitudinal follow-up.

  10. A novel approach to quantitating leukemia fusion transcripts by qRT-PCR without the need for standard curves.

    PubMed

    Schumacher, Jonathan A; Scott Reading, N; Szankasi, Philippe; Matynia, Anna P; Kelley, Todd W

    2015-08-01

    Acute myeloid leukemia patients with recurrent cytogenetic abnormalities including inv(16);CBFB-MYH11 and t(15;17);PML-RARA may be assessed by monitoring the levels of the corresponding abnormal fusion transcripts by quantitative reverse transcription-PCR (qRT-PCR). Such testing is important for evaluating the response to therapy and for the detection of early relapse. Existing qRT-PCR methods are well established and in widespread use in clinical laboratories but they are laborious and require the generation of standard curves. Here, we describe a new method to quantitate fusion transcripts in acute myeloid leukemia by qRT-PCR without the need for standard curves. Our approach uses a plasmid calibrator containing both a fusion transcript sequence and a reference gene sequence, representing a perfect normalized copy number (fusion transcript copy number/reference gene transcript copy number; NCN) of 1.0. The NCN of patient specimens can be calculated relative to that of the single plasmid calibrator using experimentally derived PCR efficiency values. We compared the data obtained using the plasmid calibrator method to commercially available assays using standard curves and found that the results obtained by both methods are comparable over a broad range of values with similar sensitivities. Our method has the advantage of simplicity and is therefore lower in cost and may be less subject to errors that may be introduced during the generation of standard curves.

  11. [Analysis of DEK-CAN fusion gene expression in acute myeloid leukemia patients with 6; 9 chromosome translocation].

    PubMed

    Wang, Ya-Lun; Wang, Tong; Xu, Feng; Gang, Yan; Wang, Jie

    2006-04-01

    This study was aimed to explore the relationship of 6; 9 chromosome translocation with DEK-CAN fusion gene expression in patients with acute myeloid leukemia (AML) and its clinical significance. Chromosome specimens were prepared by routine method after short-term culture of bone marrow cells; karyotype analysis was performed by R banding technique; the expression of fusion gene DEK-CAN was analyzed by RT-nested-PCR in mononuclear cells of bone marrow or peripheral blood of 4 AML patients, for 3 patients received allo-BMT out of 4 patients the dynamic follow-up was performed. The results indicated that t (6; 9) (p23; q34) was confirmed by chromosome karyotype analysis in the four AML patients. The DEK-CAN fusion gene was found during in all four de novo, relapsed and CR patients (100%). And the expression of DEK-CAN fusion gene enhanced apparently in de novo and relapsed patients, and weakened in CR patient. DEK-CAN mRNA was found in the three patients during 1-24 months after allo-BMT. Clinical data showed 2 patients relapsed and died after CR for 1-24 months; the other two patients received allo-BMT got CR and still survive. It is concluded that DEK-CAN fusion gene is the molecular basis in pathogenesis of AML. The detection of DEK-CAN fusion gene is significant for diagnosis of AML, evaluation of curative effect, and predication of prognosis.

  12. Acute leukemias of different lineages have similar MLL gene fusions encoding related chimeric proteins resulting from chromosomal translocation

    SciTech Connect

    Corral, J.; Forster, A.; Thompson, S.; Rabbitts, T.H. ); Lampert, F. ); Kaneko, Y. ); Slater, R.; Kroes, W.G. ); Van Der Schoot, C.E. ); Ludwig, W.D. ); Karpas, A. ); Pocock, C.; Cotter, F. )

    1993-09-15

    The MLL gene, on human chromosome 11q23, undergoes chromosomal translocation in acute leukemias, resulting in gene fusion with AF4 (chromosome 4) and ENL (chromosome 19). The authors report here translocation of MLL with nine different chromosomes and two paracentric chromosome 11 deletions in early B cell, B- or T-cell lineage, or nonlymphocytic acute leukemias. The mRNA translocation junction from 22t(4;11) patients, including six adult leukemias, and nine t(11;19) tumors reveals a remarkable conservation of breakpoints within MLL, AF4, or ENL genes, irrespective of tumor phenotype. Typically, the breakpoints are upstream of the zinc-finger region of MLL, and deletion of this region can accompany translocation, supporting the der(11) chromosome as the important component in leukemogenesis. Partial sequence of a fusion between MLL and the AFX1 gene from chromosome X shows the latter to be rich in Ser/Pro codons, like the ENL mRNA. These data suggest that the heterogeneous 11q23 abnormalities might cause attachment of Ser/Pro-rich segments to the NH[sub 2] terminus of MLL, lacking the zinc-finger region, and that translocation occurs in early hematopoietic cells, before commitment to distinct lineages. 36 refs., 2 figs.

  13. Generation and preclinical characterization of an NKp80-Fc fusion protein for redirected cytolysis of natural killer (NK) cells against leukemia.

    PubMed

    Deng, Gang; Zheng, Xiaodong; Zhou, Jing; Wei, Haiming; Tian, Zhigang; Sun, Rui

    2015-09-11

    The capacity of natural killer (NK) cells to mediate Fc receptor-dependent effector functions, such as antibody-dependent cellular cytotoxicity (ADCC), largely contributes to their clinical application. Given that activation-induced C-type lectin (AICL), an identified ligand for the NK-activating receptor NKp80, is frequently highly expressed on leukemia cells, the lack of therapeutic AICL-specific antibodies limits clinical application. Here we explore a strategy to reinforce NK anti-leukemia reactivity by combining targeting AICL-expressing leukemia cells with the induction of NK cell ADCC using NKp80-Fc fusion proteins. The NKp80-Fc fusion protein we generated bound specifically to leukemia cells in an AICL-specific manner. Cell binding assays between NK and leukemia cells showed that NKp80-Fc significantly increased NK target cell conjugation. In functional analyses, treatment with NKp80-Fc clearly induced the ADCC effect of NK cells. NKp80-Fc not only promoted NK-mediated leukemia cell apoptosis in the early stage of cell conjugation but also enhanced NK cell degranulation and cytotoxicity activity in the late stage. The bifunctional NKp80-Fc could redirect NK cells toward leukemia cells and triggered NK cell killing in vitro. Moreover, NKp80-Fc enhanced the lysis of NK cells against tumors in leukemia xenograft non-obese diabetic/severe combined immunodeficiency mice. Taken together, our results demonstrate that NKp80-Fc potently amplifies NK cell anti-leukemia effects in vitro and in vivo through induction of the NK cell ADCC effect. This method could potentially be useful for molecular targeted therapy, and the fusion proteins may be a promising drug for immunotherapy of leukemia.

  14. A novel BCR-ABL1 fusion gene identified by next-generation sequencing in chronic myeloid leukemia.

    PubMed

    Lyu, Xiaodong; Yang, Jingke; Wang, Xianwei; Hu, Jieying; Liu, Bing; Zhao, Yu; Guo, Zhen; Liu, Bingshan; Fan, Ruihua; Song, Yongping

    2016-01-01

    BCR-ABL1 fusion proteins contain constitutively active tyrosine kinases that are potential candidates for targeted therapy with tyrosine kinase inhibitors such as imatinib in chronic myeloid leukemia (CML). However, uncharacterized BCR-ABL1 fusion genes can be missed by quantitative RT-PCR (qRT-PCR)-based routine screening methods, causing adverse effect on drug selection and treatment outcome. In this study, we demonstrated that the next-generation sequencing (NGS) can be employed to overcome this obstacle. Through NGS, we identified a novel BCR-ABL1 fusion gene with breakpoints in the BCR intron 14 and the ABL1 intron 2, respectively, in a rare case of CML. Its mRNA with an e14a3 junction was then detected using customized RT-PCR followed by Sanger sequencing. Subsequently, the patient received targeted medicine imatinib initially at 400 mg/day, and later 300 mg/day due to intolerance reactions. With this personalized treatment, the patient's condition was significantly improved. Interestingly, this novel fusion gene encodes a fusion protein containing a compromised SH3 domain, which is usually intact in the majority of CML cases, suggesting that dysfunctional SH3 domain may be associated with altered drug response and unique clinicopathological manifestations observed in this patient. We identified a novel BCR-ABL1 fusion gene using NGS in a rare case of CML while routine laboratory procedures were challenged, demonstrating the power of NGS as a diagnostic tool for detecting novel genetic mutations. Moreover, our new finding regarding the novel fusion variant will provide useful insights to improve the spectrum of the genomic abnormalities recognizable by routine molecular screening.

  15. Hh/Gli antagonist in acute myeloid leukemia with CBFA2T3-GLIS2 fusion gene.

    PubMed

    Masetti, Riccardo; Bertuccio, Salvatore Nicola; Astolfi, Annalisa; Chiarini, Francesca; Lonetti, Annalisa; Indio, Valentina; De Luca, Matilde; Bandini, Jessica; Serravalle, Salvatore; Franzoni, Monica; Pigazzi, Martina; Martelli, Alberto Maria; Basso, Giuseppe; Locatelli, Franco; Pession, Andrea

    2017-01-21

    CBFA2T3-GLIS2 is a fusion gene found in 17% of non-Down syndrome acute megakaryoblastic leukemia (non-DS AMKL, FAB M7) and in 8% of pediatric cytogenetically normal acute myeloid leukemia (CN-AML, in association with several French-American-British (FAB) subtypes). Children with AML harboring this aberration have a poor outcome, regardless of the FAB subtype. This fusion gene drives a peculiar expression pattern and leads to overexpression of some of Hedgehog-related genes. GLI-similar protein 2 (GLIS2) is closely related to the GLI family, the final effectors of classic Hedgehog pathway. These observations lend compelling support to the application of GLI inhibitors in the treatment of AML with the aberration CBFA2T3-GLIS2. GANT61 is, nowadays, the most potent inhibitor of GLI family proteins. We exposed to GANT61 AML cell lines and primary cells positive and negative for CBFA2T3-GLIS2 and analyzed the effect on cellular viability, induction of apoptosis, cell cycle, and expression profile. As compared to AML cells without GLIS2 fusion, GANT61 exposure resulted in higher sensitivity of both cell lines and primary AML cells carrying CBFA2T3-GLIS2 to undergo apoptosis and G1 cell cycle arrest. Remarkably, gene expression studies demonstrated downregulation of GLIS2-specific signature genes in both treated cell lines and primary cells, in comparison with untreated cells. Moreover, chromatin immunoprecipitation analysis revealed direct regulation by GLIS2 chimeric protein of DNMT1 and DNMT3B, two genes implicated in important epigenetic functions. Our findings indicate that the GLI inhibitor GANT61 may be used to specifically target the CBFA2T3-GLIS2 fusion gene in pediatric AML.

  16. Fusion of the TEL gene on 12p13 to the AML1 gene on 21q22 in acute lymphoblastic leukemia

    SciTech Connect

    Barker, G.F.; Golub, T.R.; Gilliland, D.G.; Bohlander, S.K.; Rowley, J.D.; Heibert, S.W.; Raimondi, S.C.; Ward, D.C.; Bray-Ward, P.; Morgan, E.

    1995-05-23

    Chromosomal rearrangements involving band 12p13 are found in a wide variety of human leukemias but are particularly common in childhood acute lymphoblastic leukemia. The genes involved in these rearrangements, however, have not been identified. We now report the cloning of a t(12;21) translocation breakpoint involving 12p13 and 21q22 in two cases of childhood pre-B acute lymphoblastic leukemia, in which t(12;21) rearrangements were not initially apparent. The consequence of the translocation is fusion of the helix-loop-helix domain of TEL, an ETS-like putative transcription factor, to the DNA-binding and transactivation domains of the transcription factor AML1. These data show that TEL, previously shown to be fused to the platelet-derived growth factor receptor {beta} in chronic myelomonocytic leukemia, can be implicated in the pathogenesis of leukemia through its fusion to either a receptor tyrosine kinase or a transcription factor. The TEL-AML1 fusion also indicates that translocations affecting the AML1 gene can be associated with lymphoid, as well as myeloid, malignancy. 23 refs., 5 figs.

  17. ZNF384-related fusion genes define a subgroup of childhood B-cell precursor acute lymphoblastic leukemia with a characteristic immunotype

    PubMed Central

    Hirabayashi, Shinsuke; Ohki, Kentaro; Nakabayashi, Kazuhiko; Ichikawa, Hitoshi; Momozawa, Yukihide; Okamura, Kohji; Yaguchi, Akinori; Terada, Kazuki; Saito, Yuya; Yoshimi, Ai; Ogata-Kawata, Hiroko; Sakamoto, Hiromi; Kato, Motohiro; Fujimura, Junya; Hino, Moeko; Kinoshita, Akitoshi; Kakuda, Harumi; Kurosawa, Hidemitsu; Kato, Keisuke; Kajiwara, Ryosuke; Moriwaki, Koichi; Morimoto, Tsuyoshi; Nakamura, Kozue; Noguchi, Yasushi; Osumi, Tomoo; Sakashita, Kazuo; Takita, Junko; Yuza, Yuki; Matsuda, Koich; Yoshida, Teruhiko; Matsumoto, Kenji; Hata, Kenichiro; Kubo, Michiaki; Matsubara, Yoichi; Fukushima, Takashi; Koh, Katsuyoshi; Manabe, Atsushi; Ohara, Akira; Kiyokawa, Nobutaka

    2017-01-01

    Fusion genes involving ZNF384 have recently been identified in B-cell precursor acute lymphoblastic leukemia, and 7 fusion partners have been reported. We further characterized this type of fusion gene by whole transcriptome sequencing and/or polymerase chain reaction. In addition to previously reported genes, we identified BMP2K as a novel fusion partner for ZNF384. Including the EP300-ZNF384 that we reported recently, the total frequency of ZNF384-related fusion genes was 4.1% in 291 B-cell precursor acute lymphoblastic leukemia patients enrolled in a single clinical trial, and TCF3-ZNF384 was the most recurrent, with a frequency of 2.4%. The characteristic immunophenotype of weak CD10 and aberrant CD13 and/or CD33 expression was revealed to be a common feature of the leukemic cells harboring ZNF384-related fusion genes. The signature gene expression profile in TCF3-ZNF384-positive patients was enriched in hematopoietic stem cell features and related to that of EP300-ZNF384-positive patients, but was significantly distinct from that of TCF3-PBX1-positive and ZNF384-fusion-negative patients. However, clinical features of TCF3-ZNF384-positive patients are markedly different from those of EP300-ZNF384-positive patients, exhibiting higher cell counts and a younger age at presentation. TCF3-ZNF384-positive patients revealed a significantly poorer steroid response and a higher frequency of relapse, and the additional activating mutations in RAS signaling pathway genes were detected by whole exome analysis in some of the cases. Our observations indicate that ZNF384-related fusion genes consist of a distinct subgroup of B-cell precursor acute lymphoblastic leukemia with a characteristic immunophenotype, while the clinical features depend on the functional properties of individual fusion partners. PMID:27634205

  18. Establishment of a myeloid leukemia cell line, TRL-01, with MLL-ENL fusion gene.

    PubMed

    Ninomiya, Manabu; Abe, Akihiro; Yokozawa, Toshiya; Ozeki, Kazutaka; Yamamoto, Kazuhito; Ito, Mamoru; Ito, Masafumi; Kiyoi, Hitoshi; Emi, Nobuhiko; Naoe, Tomoki

    2006-08-01

    We established a leukemia cell line derived from therapy-related acute myeloid leukemia with the t(11;19) by xenotransplantation into the NOD/SCID mouse with IL-2Rgamma(c)-/- (NOG mouse). The cell line, TRL-01, could be serially transplanted from mouse to mouse and also grown in an adherence-dependent manner on a murine bone marrow stroma cell line, HESS-5. TRL-01 had the same immunophenotype as the original leukemia cells: positive for CD13, CD33, CD11a, CD18, CD29, CD49d, CD49e, CD54, CD62L, and CD117, and negative for CD3, CD4, CD8, CD19, CD34, CD41a, CD41b, CD135, and myeloperoxidase. Translocation (11;19)(q23;p13) in both the original sample and TRL-01 generated MLL-ENL chimeric transcripts joining exon 6 and exon 4, respectively, which has a novel isoform. In cultures of TRL-01, addition of GM-CSF, SCF, and G-CSF and adhesion to fibronectin-coated plates promoted transient proliferation and survival, although they did not support long-term culture. Subcutaneous injection caused a tumor to form only when HESS-5 was coinjected at the same site. These results suggest that TRL-01 is a useful cell line for studying not only the leukemia-related biology of MLL-ENL but also the intercellular association between leukemia and stroma.

  19. A leukemia fusion protein attenuates the spindle checkpoint and promotes aneuploidy

    PubMed Central

    Boyapati, Anita; Yan, Ming; Peterson, Luke F.; Biggs, Joseph R.; Le Beau, Michelle M.

    2007-01-01

    The 8;21 chromosomal translocation occurs in 15% to 40% of patients with the FAB M2 subtype of acute myeloid leukemia (AML). This chromosomal abnormality fuses part of the AML1/RUNX1 gene to the ETO/MTG8 gene and generates the AML1-ETO protein. We previously identified a C-terminal truncated AML1-ETO protein (AEtr) in a mouse leukemia model. AEtr is almost identical to the AML1-ETO exon 9a isoform expressed in leukemia patients. Here, we describe a novel function of AEtr in the development of aneuploidy through spindle checkpoint attenuation. AEtr cells had a reduced mitotic index following nocodazole treatment, suggesting a failure in a subset of cells to arrest in mitosis with a functional spindle checkpoint. Additionally, primary leukemia cells and cell lines expressing AEtr were aneuploid. Moreover, AEtr cells had reduced levels of several spindle checkpoint proteins including BubR1 and securin following treatment with the spindle poison nocodazole. These results suggest that inactivation of the spindle checkpoint may contribute to the development of aneuploidy described in t(8;21) leukemia patients. PMID:17197431

  20. Caspases mediate retinoic acid-induced degradation of the acute promyelocytic leukemia PML/RARalpha fusion protein.

    PubMed

    Nervi, C; Ferrara, F F; Fanelli, M; Rippo, M R; Tomassini, B; Ferrucci, P F; Ruthardt, M; Gelmetti, V; Gambacorti-Passerini, C; Diverio, D; Grignani, F; Pelicci, P G; Testi, R

    1998-10-01

    All-trans-retinoic acid (RA) treatment induces morphological remission in acute promyelocytic leukemia (APL) patients carrying the t(15;17) and expressing the PML/RARalpha product by inducing terminal differentiation of the leukemic clone. RA treatment induces downregulation of PML/RARalpha and reorganization of the PML-nuclear bodies. These events have been proposed to be essential for the induction of APL cell differentiation by RA. Here, we show that in the APL-derived NB4 cell line as well as in myeloid precursor U937 cells expressing the PML/RARalpha (U937/PR9) and in blasts from APL patients, the PML/RARalpha fusion protein is cleaved by a caspase 3-like activity induced by RA treatment. In fact, a caspase 3-like activity is detectable in PML/RARalpha expressing cells after RA treatment, and selective caspase inhibitor peptides are able to prevent the RA-induced degradation of the fusion protein in vivo and in vitro. Using recombinant caspases and PML/RARalpha deletion mutants we mapped a caspase 3 cleavage site (Asp 522) within the alpha-helix region of the PML component of the fusion protein. The extent of PML/RARalpha cleavage directly correlates with the ability of RA to restore the normal PML nuclear bodies (NBs) pattern. However, RA-induced differentiation is not prevented by the persistence of the fusion product and occurs in the absence of normally structured PML NBs. These results indicate that PML/RARalpha is directly involved in conferring RA sensitivity of APL cells and that the RA-induced reassembly of PML NBs is the consequence of the disappearance of PML/RARalpha.

  1. Fusion-defective gibbon ape leukemia virus vectors can be rescued by homologous but not heterologous soluble envelope proteins.

    PubMed

    Farrell, Karen B; Ting, Yuan-Tsang; Eiden, Maribeth V

    2002-05-01

    Murine leukemia virus (MLV)-derived envelope proteins containing alterations in or adjacent to the highly conserved PHQ motif present at the N terminus of the envelope surface subunit (SU) are incorporated into vector particles but are not infectious due to a postbinding block to viral entry. These mutants can be rendered infectious by the addition of soluble receptor-binding domain (RBD) proteins in the culture medium. The RBD proteins that rescue the infectivity of these defective MLV vectors can be derived from the same MLV or from other MLVs that use distinct receptors to mediate entry. We have now constructed functional immunologically reactive gibbon ape leukemia virus (GALV) envelope proteins, tagged with a feline leukemia virus (FeLV)-derived epitope tag, which are efficiently incorporated into infectious particles. Tagged GALV envelope proteins bind specifically to cells expressing the phosphate transporter protein Pit1, demonstrating for the first time that Pit1 is the binding receptor for GALV and not a coreceptor or another type of GALV entry factor. We have also determined that GALV particles bearing SU proteins with an insertion C-terminal to the PHQ motif (GALV I(10)) bind Pit1 but fail to infect cells. Incubation with soluble GALV RBD renders GALV I(10) particles infectious, whereas incubation with soluble RBDs from MLV or FeLV-B does not. This finding is consistent with the results obtained by Lauring et al. using FeLV-T, a virus that employs Pit1 as a receptor but requires soluble FeLV RBD for entry. MLV and GALV RBDs are not able to render FeLV-T infectious (A. S. Lauring, M. M. Anderson, and J. Overbaugh, J. Virol. 75:8888-8898, 2001). Together, these results suggest that fusion-defective FeLV-T and GALV are restricted to homologous RBD rescue of infectivity.

  2. Expression of Glucose Transporter 1 Confers Susceptibility to Human T-Cell Leukemia Virus Envelope-Mediated Fusion

    PubMed Central

    Coskun, Ayse Kubra; Sutton, Richard E.

    2005-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) was the first human retrovirus identified and causes both adult T-cell leukemia/lymphoma and tropical spastic paraparesis/HTLV-1-associated myelopathy, among other disorders. In vitro, HTLV-1 has an extremely broad host cell tropism in that it is capable of infecting most mammalian cell types, although at the same time viral titers remain relatively low. Despite years of study, only recently has a bona fide candidate cellular receptor, glucose transporter 1 (glut-1), been identified. Although glut-1 was shown to bind specifically to the ectodomain of HTLV-1 and HTLV-2 envelope glycoproteins, which was reversible with small interfering RNA directed against glut-1, cellular susceptibility to HTLV upon expression of glut-1 was not established. Here we show that expression of glut-1 in relatively resistant MDBK cells conferred increased susceptibility to both HTLV-1- and HTLV-2-pseudotyped particles. glut-1 also markedly increased syncytium formation in MDBK cells after exposure to HTLV-1. Another assay also demonstrated HTLV-1 envelope-cell fusion in the presence of glut-1. Taken together, these results provide additional evidence that glut-1 is a receptor for HTLV. PMID:15767416

  3. Small Molecule Disrupts Abnormal Gene Fusion Associated with Leukemia | Center for Cancer Research

    Cancer.gov

    Rare chromosomal abnormalities, called chromosomal translocations, in which part of a chromosome breaks off and becomes attached to another chromosome, can result in the generation of chimeric proteins. These aberrant proteins have unpredictable, and sometimes harmful, functions, including uncontrolled cell growth that can lead to cancer. One type of translocation, in which a portion of the gene encoding nucleoporin 98 (NUP98)—one of about 50 proteins comprising the nuclear pore complex through which proteins are shuttled into and out of the nucleus—fuses with another gene, has been shown to result in improper histone modifications. These abnormalities alter the gene expression patterns of certain types of hematopoietic, or blood-forming, stem cells, resulting primarily in overexpression of the Hoxa7, Hoxa9,and Hoxa10 genes. NUP98 chromosomal translocations have been associated with many types of leukemia, including acute myeloid leukemia (AML), acute lymphoid leukemia (ALL), chronic myeloid leukemia in blast crisis (CML-bc), and myelodysplastic syndrome (MDS).

  4. Molecular studies reveal a MLL-MLLT3 gene fusion displaced in a case of childhood acute lymphoblastic leukemia with complex karyotype.

    PubMed

    Ney Garcia, Daniela Ribeiro; Liehr, Thomas; Emerenciano, Mariana; Meyer, Claus; Marschalek, Rolf; Pombo-de-Oliveira, Maria do Socorro; Ribeiro, Raul C; Poirot Land, Marcelo Gerardin; Macedo Silva, Maria Luiza

    2015-04-01

    Rearrangement of the mixed lineage-leukemia gene (MLL-r) is common in hematological diseases and is generally associated with poor prognosis. The mixed-lineage leukemia gene translocated to, 3 (MLLT3) gene (9p22) is a frequent MLL-r partner (∼18% of leukemias with MLL rearrangement) and is characterized by the translocation t(9;11) (p22;q23), forming an MLL-MLLT3 gene fusion. MLL-r are usually simple reciprocal translocations between two different chromosomes, although karyotypes with complex MLL-r have been observed. We present a rare case of a child with acute lymphoblastic leukemia with a complex karyotype in which the classical t(9;11) (p22;q23) was cryptically relocated into a third chromosome in a balanced three-way translocation. At the genome level, however, the MLL-MLLT3 three-way translocation still displayed both reciprocal fusion transcripts. This argues in favor for a model where a simple two-way t(9;11) (p22;q23) was likely the first step that then evolved in to a more complex karyotype. Multicolor banding techniques can be used to greatly refine complex karyotypes and its chromosomal breakpoints. Also in the presence of putative new rearrangements, Long distance inverse-PCR is an important tool to identify which gene fusion is involved.

  5. Modified DT-IL2 fusion toxin targeting uniquely IL2Ralpha expressing leukemia cell lines - Construction and characterization.

    PubMed

    Potala, Sirisha; Verma, Rama S

    2010-07-20

    Immunotoxins are fusion proteins of modified toxin conjugated to tumor cell selective ligand. Denileukin diftitox approved by FDA for treatment of CTCL is diphtheria toxin (DT)/IL2 fusion protein targeted to high affinity IL2R. Here, we have attempted to target the more uniquely expressed low affinity IL2R (IL2Ralpha). We designed four immunotoxins, SPRSV1 was designed to code for a single protein of DT (390) and IL2 (133) without any extra amino acids at the junction. SPRSV2 was designed to selectively target low affinity IL2R, it codes for DT (390) and IL2 (69). We also constructed SPRSV3 encoding for only DT (390) without any ligand, as negative control and SPRSV4 was designed similar to commercial equivalent denileukin diftitox, it codes for DT (387) and IL2 (133) with His at the junction. The cytotoxic activities of these immunotoxins were tested in various cell lines, cell lines lacking IL2R expression and healthy MNC were used as controls. The activities of SPRSV1 and SPRSV2 were comparable to that of SPRSV4. SPRSV2 exhibited potent cytotoxicity effectively targeted to alpha subunit of IL2R on various leukemia cell lines. Our studies also showed a negative correlation between CD25 expression and percentage cell viability after treatment with immunotoxins. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  6. Direct and Indirect Targets of the E2A-PBX1 Leukemia-Specific Fusion Protein

    PubMed Central

    Diakos, Christofer; Xiao, Yuanyuan; Zheng, Shichun; Kager, Leo; Dworzak, Michael; Wiemels, Joseph L.

    2014-01-01

    E2A-PBX1 is expressed as a result of the t(1;19) chromosomal translocation in nearly 5% of cases of childhood acute lymphoblastic leukemia. The E2A-PBX1 chimeric transcription factor contains the N-terminal transactivation domain of E2A (TCF3) fused to the C-terminal DNA-binding homeodomain of PBX1. While there is no doubt of its oncogenic potential, the mechanisms of E2A-PBX1-mediated pre-B cell transformation and the nature of direct E2A-PBX1 target genes and pathways remain largely unknown. Herein we used chromatin immunoprecipitation assays (ChIP-chip) to identify direct targets of E2A-PBX1, and we used gene expression arrays of siRNA E2A-PBX1-silenced cells to evaluate changes in expression induced by the fusion protein. Combined ChIP-chip and expression data analysis gave rise to direct and functional targets of E2A-PBX1. Further we observe that the set of ChIP-chip identified E2A-PBX1 targets show a collective down-regulation trend in the E2A-PBX1 silenced samples compared to controls suggesting an activating role of this fusion transcription factor. Our data suggest that the expression of the E2A-PBX1 fusion gene interferes with key regulatory pathways and functions of hematopoietic biology. Among these are members of the WNT and apoptosis/cell cycle control pathways, and thus may comprise an essential driving force for the propagation and maintenance of the leukemic phenotype. These findings may also provide evidence of potentially attractive therapeutic targets. PMID:24503810

  7. Resistance against Friend leukemia virus-induced leukemogenesis in DNA-dependent protein kinase (DNA-PK)-deficient scid mice associated with defective viral integration at the Spi-1 and Fli-1 site.

    PubMed

    Hasegawa, Maki; Yamaguchi, Shuichi; Aizawa, Shiro; Ikeda, Hidetoshi; Tatsumi, Kouichi; Noda, Yuko; Hirokawa, Katsuiku; Kitagawa, Masanobu

    2005-08-01

    Retroviral DNA integration is mediated by the viral protein integrase. However, elements of the host DNA repair machinery such as the phosphatidylinositol 3-kinase (PI-3K)-related protein kinase family system would play a role in the integration of viral DNA into the host DNA. Here, we show that a host PI-3K-related protein kinase, DNA-dependent protein kinase (DNA-PK), plays a role in the specific integration of retroviral DNA and induction of retroviral diseases in vivo. DNA-PK-deficient scid mice inoculated with Friend leukemia virus (FLV) exhibited a random integration into their genomic DNA and expressed the viral envelope protein gp70. However, the specific integration of FLV at Spi-1 or Fli-1 sites did not occur in association with the significant resistance of scid mice to FLV-induced leukemogenesis. In contrast, the knockout of another member of the PI-3K-related protein kinase family, encoded by the ataxia telangiectasia mutated (ATM) gene, resulted in mice as sensitive to FLV-induced leukemogenesis as the wild type mice. FLV was specifically integrated into the DNA at Spi-1 and Fli-1 sites with significant expression of these transcription factors. These findings indicated that DNA-PK would be essential for controlling the in vivo integration of FLV at specific sites as well as the susceptibility to FLV-induced leukemogenesis.

  8. Increased synthesis and expression of H-2 antigens on thymocytes as a result of radiation leukemia virus infection: a possible mechanism for H-2 linked control of virus-induced neoplasia

    PubMed Central

    1978-01-01

    Previous studies from this laboratory have mapped resistance and/or susceptibility to radiation-induced leukemia virus (RadLV)-induced neoplasia to the H-2D region. H-2 linked effects on virus replication can be detected subsequent to the initial virus infection, and clear- cut differences in numbers of virus infected thymus cells can be detected as early as 5 wk after RadLV inoculation. Rapid increases in cellular synthesis and cell surface expression of H-2 antigens are detectable immediately after virus inoculation. These changes have been studied by immunofluorescence, absorption, cell surface iodination followed by sodium dodecyl-sulfate-polyacrylamide gel electrophoresis, and two dimensional gel electrophoretic analysis of internally labeled lymphocyte proteins. Expression of H-2K molecules is significantly increased in cells of susceptible and resistant animals. However, significant increases in expression of H-2D antigens occurs only on thymus cells from resistant strains (H-2Dd). Transformed cells of resistant and susceptible H-2 haplotypes adapted to tissue culture lack detectable H-2 antigens as determined by serological absorption studies. It is argued that altered expression of H-2 antigens plays a very significant role in the mechanism of host defense to virus infection. PMID:75239

  9. Genome-wide repression of eRNA and target gene loci by the ETV6-RUNX1 fusion in acute leukemia.

    PubMed

    Teppo, Susanna; Laukkanen, Saara; Liuksiala, Thomas; Nordlund, Jessica; Oittinen, Mikko; Teittinen, Kaisa; Grönroos, Toni; St-Onge, Pascal; Sinnett, Daniel; Syvänen, Ann-Christine; Nykter, Matti; Viiri, Keijo; Heinäniemi, Merja; Lohi, Olli

    2016-11-01

    Approximately 20%-25% of childhood acute lymphoblastic leukemias carry the ETV6-RUNX1 (E/R) fusion gene, a fusion of two central hematopoietic transcription factors, ETV6 (TEL) and RUNX1 (AML1). Despite its prevalence, the exact genomic targets of E/R have remained elusive. We evaluated gene loci and enhancers targeted by E/R genome-wide in precursor B acute leukemia cells using global run-on sequencing (GRO-seq). We show that expression of the E/R fusion leads to widespread repression of RUNX1 motif-containing enhancers at its target gene loci. Moreover, multiple super-enhancers from the CD19(+)/CD20(+)-lineage were repressed, implicating a role in impediment of lineage commitment. In effect, the expression of several genes involved in B cell signaling and adhesion was down-regulated, and the repression depended on the wild-type DNA-binding Runt domain of RUNX1. We also identified a number of E/R-regulated annotated and de novo noncoding genes. The results provide a comprehensive genome-wide mapping between E/R-regulated key regulatory elements and genes in precursor B cell leukemia that disrupt normal B lymphopoiesis. © 2016 Teppo et al.; Published by Cold Spring Harbor Laboratory Press.

  10. Unexpected heterogeneity of BCR-ABL fusion mRNA detected by polymerase chain reaction in Philadelphia chromosome-positive acute lymphoblastic leukemia

    SciTech Connect

    Hooberman, A.L.; Carrino, J.J.; Leibowitz, D.; Rowley, J.D.; Le Beau, M.M.; Arlin, Z.A.; Westbrook, C.A. )

    1989-06-01

    The Philadelphia (Ph{sup 1}) chromosome results in a fusion of portions of the BCR gene from chromosome 22 and the ABL gene from chromosome 9, producing a chimeric BCR-ABL mRNA and protein. In lymphoblastic leukemias, there are two molecular subtypes of the Ph{sup 1} chromosome, one with a rearrangement of the breakpoint cluster region (bcr) of the BCR gene, producing the same 8.5-kilobase BCR-ABL fusion mRNA seen in chronic myelogenous leukemia (CML), and the other, without a bcr rearrangement, producing a 7.0-kilobase BCR-ABL fusion mRNA that is seen only in acute lymphoblastic leukemia (ALL). The authors studied the molecular subtype of the Ph{sup 1} chromosome in 11 cases of Ph{sup 1}-positive ALL, including 2 with a previous diagnosis of CML, using a sensitive method to analyze the mRNA species based on the polymerase chain reaction (PCR). They observed unexpected heterogeneity in BCR-ABL mRNA in this population. They conclude that the PCR gives additional information about the Ph{sup 1} chromosome gene products that cannot be obtained by genomic analysis, but that it cannot be used as the sole means of detection of this chromosomal abnormality in ALL because of the high incidence of false negative results.

  11. Multiplexed automated digital quantification of fusion transcripts: comparative study with fluorescent in-situ hybridization (FISH) technique in acute leukemia patients.

    PubMed

    Akhter, Ariz; Mughal, Muhammad Kashif; Elyamany, Ghaleb; Sinclair, Gary; Azma, Raja Zahratul; Masir, Noraidah; Shuib, Salwati; Rashid-Kolvear, Fariborz; Shabani-Rad, Meer-Taher; Stewart, Douglas Allan; Mansoor, Adnan

    2016-09-15

    The World Health Organization (WHO) classification system defines recurrent chromosomal translocations as the sole diagnostic and prognostic criteria for acute leukemia (AL). These fusion transcripts are pivotal in the pathogenesis of AL. Clinical laboratories universally employ conventional karyotype/FISH to detect these chromosomal translocations, which is complex, labour intensive and lacks multiplexing capacity. Hence, it is imperative to explore and evaluate some newer automated, cost-efficient multiplexed technologies to accommodate the expanding genetic landscape in AL. "nCounter® Leukemia fusion gene expression assay" by NanoString was employed to detect various fusion transcripts in a large set samples (n = 94) utilizing RNA from formalin fixed paraffin embedded (FFPE) diagnostic bone marrow biopsy specimens. This series included AL patients with various recurrent translocations (n = 49), normal karyotype (n = 19), or complex karyotype (n = 21), as well as normal bone marrow samples (n = 5). Fusion gene expression data were compared with results obtained by conventional karyotype and FISH technology to determine sensitivity/specificity, as well as positive /negative predictive values. Junction probes for PML/RARA; RUNX1-RUNX1T1; BCR/ABL1 showed 100 % sensitivity/specificity. A high degree of correlation was noted for MLL/AF4 (85 sensitivity/100 specificity) and TCF3-PBX1 (75 % sensitivity/100 % specificity) probes. CBFB-MYH11 fusion probes showed moderate sensitivity (57 %) but high specificity (100 %). ETV6/RUNX1 displayed discordance between fusion transcript assay and FISH results as well as rare non-specific binding in AL samples with normal or complex cytogenetics. Our study presents preliminary data with high correlation between fusion transcript detection by a throughput automated multiplexed platform, compared to conventional karyotype/FISH technique for detection of chromosomal translocations in AL patients. Our

  12. Novel real-time polymerase chain reaction assay for simultaneous detection of recurrent fusion genes in acute myeloid leukemia.

    PubMed

    Dolz, Sandra; Barragán, Eva; Fuster, Óscar; Llop, Marta; Cervera, José; Such, Esperanza; De Juan, Inmaculada; Palanca, Sarai; Murria, Rosa; Bolufer, Pascual; Luna, Irene; Gómez, Inés; López, María; Ibáñez, Mariam; Sanz, Miguel A

    2013-09-01

    The recent World Health Organization classification recognizes different subtypes of acute myeloid leukemia (AML) according to the presence of several recurrent genetic abnormalities. Detection of these abnormalities and other molecular changes is of increasing interest because it contributes to a refined diagnosis and prognostic assessment in AML and enables monitoring of minimal residual disease. These genetic abnormalities can be detected using single RT-PCR, although the screening is still labor intensive and costly. We have developed a novel real-time RT-PCR assay to simultaneously detect 15 AML-associated rearrangements that is a simple and easily applicable method for use in clinical diagnostic laboratories. This method showed 100% specificity and sensitivity (95% confidence interval, 91% to 100% and 92% to 100%, respectively). The procedure was validated in a series of 105 patients with AML. The method confirmed all translocations detected using standard cytogenetics and fluorescence in situ hybridization and some additional undetected rearrangements. Two patients demonstrated two molecular rearrangements simultaneously, with BCR-ABL1 implicated in both, in addition to RUNX1-MECOM in one patient and PML-RARA in another. In conclusion, this novel real-time RT-PCR assay for simultaneous detection of multiple AML-associated fusion genes is a versatile and sensitive method for reliable screening of recurrent rearrangements in AML.

  13. DC-SIGN Facilitates Fusion of Dendritic Cells with Human T-Cell Leukemia Virus Type 1-Infected Cells

    PubMed Central

    Ceccaldi, Pierre-Emmanuel; Delebecque, Frédéric; Prevost, Marie-Christine; Moris, Arnaud; Abastado, Jean-Pierre; Gessain, Antoine; Schwartz, Olivier; Ozden, Simona

    2006-01-01

    Interactions between the oncogenic retrovirus human T-cell leukemia virus type 1 (HTLV-1) and dendritic cells (DCs) are poorly characterized. We show here that monocyte-derived DCs form syncytia and are infected upon coculture with HTLV-1-infected lymphocytes. We examined the role of DC-specific ICAM-3-grabbing nonintegrin (DC-SIGN), a C-type lectin expressed in DCs, in HTLV-1-induced syncytium formation. DC-SIGN is known to bind with high affinity to various viral envelope glycoproteins, including human immunodeficiency virus (HIV) and hepatitis C virus, as well as to the cellular receptors ICAM-2 and ICAM-3. After cocultivating DCs and HTLV-1-infected cells, we found that anti-DC-SIGN monoclonal antibodies (MAbs) were able to decrease the number and size of HTLV-1-induced syncytia. Moreover, expression of the lectin in epithelial-cell lines dramatically enhanced the ability to fuse with HTLV-1-positive cells. Interestingly, in contrast to the envelope (Env) glycoproteins of HIV and other viruses, that of HTLV-1 does not bind directly to DC-SIGN. The facilitating role of the lectin in HTLV-1 syncytium formation is mediated by its interaction with ICAM-2 and ICAM-3, as demonstrated by use of MAbs directed against these adhesion molecules. Altogether, our results indicate that DC-SIGN facilitates HTLV-1 infection and fusion of DCs through an ICAM-dependent mechanism. PMID:16641270

  14. Flt3 does not play a critical role in murine myeloid leukemias induced by MLL fusion genes.

    PubMed

    Albouhair, Stéphanie; Morgado, Ester; Lavau, Catherine

    2013-01-01

    Leukemias harboring MLL translocations are frequent in children and adults, and respond poorly to therapies. The receptor tyrosine kinase FLT3 is highly expressed in these leukemias. In vitro studies have shown that pediatric MLL-rearranged ALL cells are sensitive to FLT3 inhibitors and clinical trials are ongoing to measure their therapeutic efficacy. We sought to determine the contribution of Flt3 in the pathogenesis of MLL-rearranged leukemias using a myeloid leukemia mouse model. Bone marrow from Flt3 null mice transduced with MLL-ENL or MLL-CBP was transplanted into host mice and Flt3 (-/-) leukemias were compared to their Flt3 wild type counterparts. Flt3 deficiency did not delay disease onset and had minimal impact on leukemia characteristics. To determine the anti-leukemic effect of FLT3 inhibition we studied the sensitivity of MLL-ENL leukemia cells to the FLT3 inhibitor PKC412 ex vivo. As previously reported for human MLL-rearranged leukemias, murine MLL-ENL leukemia cells with higher Flt3 levels were more sensitive to the cytotoxicity of PKC412. Interestingly, Flt3 deficient leukemia samples also displayed some sensitivity to PKC412. Our findings demonstrate that myeloid leukemias induced by MLL-rearranged genes are not dependent upon Flt3 signaling. They also highlight the discrepancy between the sensitivity of cells to Flt3 inhibition in vitro and the lack of contribution of Flt3 to the pathogenesis of MLL-rearranged leukemias in vivo.

  15. Bone marrow mesenchymal stem cells from infants with MLL-AF4+ acute leukemia harbor and express the MLL-AF4 fusion gene

    PubMed Central

    Catalina, Purificación; Rodríguez, René; Melen, Gustavo J.; Bueno, Clara; Arriero, Mar; García-Sánchez, Félix; Lassaletta, Alvaro; García-Sanz, Ramón

    2009-01-01

    MLL-AF4 fusion is a hallmark genetic abnormality in infant B-acute lymphoblastic leukemia (B-ALL) known to arise in utero. The cellular origin of leukemic fusion genes during human development is difficult to ascertain. The bone marrow (BM) microenvironment plays an important role in the pathogenesis of several hematological malignances. BM mesenchymal stem cells (BM-MSC) from 38 children diagnosed with cytogenetically different acute leukemias were screened for leukemic fusion genes. Fusion genes were absent in BM-MSCs of childhood leukemias carrying TEL-AML1, BCR-ABL, AML1-ETO, MLL-AF9, MLL-AF10, MLL-ENL or hyperdiploidy. However, MLL-AF4 was detected and expressed in BM-MSCs from all cases of MLL-AF4+ B-ALL. Unlike leukemic blasts, MLL-AF4+ BM-MSCs did not display monoclonal Ig gene rearrangements. Endogenous or ectopic expression of MLL-AF4 exerted no effect on MSC culture homeostasis. These findings suggest that MSCs may be in part tumor-related, highlighting an unrecognized role of the BM milieu on the pathogenesis of MLL-AF4+ B-ALL. MLL-AF4 itself is not sufficient for MSC transformation and the expression of MLL-AF4 in MSCs is compatible with a mesenchymal phenotype, suggesting a differential impact in the hematopoietic system and mesenchyme. The absence of monoclonal rearrangements in MLL-AF4+ BM-MSCs precludes the possibility of cellular plasticity or de-differentiation of B-ALL blasts and suggests that MLL-AF4 might arise in a population of prehematopoietic precursors. PMID:19995953

  16. The translocation (6;9), associated with a specific subtype of acute myeloid leukemia, results in the fusion of two genes, dek and can, and the expression of a chimeric, leukemia-specific dek-can mRNA.

    PubMed Central

    von Lindern, M; Fornerod, M; van Baal, S; Jaegle, M; de Wit, T; Buijs, A; Grosveld, G

    1992-01-01

    The translocation (6;9) is associated with a specific subtype of acute myeloid leukemia (AML). Previously, it was found that breakpoints on chromosome 9 are clustered in one of the introns of a large gene named Cain (can). cDNA probes derived from the 3' part of can detect an aberrant, leukemia-specific 5.5-kb transcript in bone marrow cells from t(6;9) AML patients. cDNA cloning of this mRNA revealed that it is a fusion of sequences encoded on chromosome 6 and 3' can. A novel gene on chromosome 6 which was named dek was isolated. In dek the t(6;9) breakpoints also occur in one intron. As a result the dek-can fusion gene, present in t(6;9) AML, encodes an invariable dek-can transcript. Sequence analysis of the dek-can cDNA showed that dek and can are merged without disruption of the original open reading frames and therefore the fusion mRNA encodes a chimeric DEK-CAN protein of 165 kDa. The predicted DEK and CAN proteins have molecular masses of 43 and 220 kDa, respectively. Sequence comparison with the EMBL data base failed to show consistent homology with any known protein sequences. Images PMID:1549122

  17. The translocation (6; 9), associated with a specific subtype of acute myeloid leukemia, results in the fusion of two genes, dek and can, and the expression of a chimeric, leukemia-specific dek-can mRNA

    SciTech Connect

    Von Lindern, M.; Fornerod, M.; Van Baal, S.; Jaegle, M.; De Wit, T.; Buijs, A.; Grosveld, G. )

    1992-04-01

    The translocation (6;9) is associated with a specific subtype of acute myeloid leukemia (AML). Previously, it was found that breakpoints on chromosome 9 are clustered in one of the introns of a large gene named Cain (can). cDNA probes derived from the 3' part of can detect an aberrant, leukemia-specific 5.5-kb transcript in bone marrow cells from t(6;9) AML patients. cDNA cloning of this mRNA revealed that it is a fusion of sequences encoded on chromosome 6 and 3' can. A novel gene on chromosome 6 which was named dek was isolated. In dek the t(6;9) breakpoints also occur in one intron. As a result the dek-can fusion gene, present in t(6;9) AML, encodes an invariable dek-can transcript. Sequence analysis of the dek-can cDNA showed that dek and can are merged without disruption of the original open reading frames and therefore the fusion mRNA encodes a chimeric DEK-CAN protein of 165 kDa. The predicted DEK and CAN proteins have molecular masses of 43 and 220 kDa, respectively. Sequence comparison with the EMBL data base failed to show consistent homology with any known protein sequences. 50 refs., 8 figs.

  18. Relationship between SU Subdomains That Regulate the Receptor-Mediated Transition from the Native (Fusion-Inhibited) to the Fusion-Active Conformation of the Murine Leukemia Virus Glycoprotein

    PubMed Central

    Lavillette, Dimitri; Ruggieri, Alessia; Boson, Bertrand; Maurice, Marielle; Cosset, François-Loïc

    2002-01-01

    Envelope glycoproteins (Env) of retroviruses are trimers of SU (surface) and TM (transmembrane) heterodimers and are expressed on virions in fusion-competent forms that are likely to be metastable. Activation of the viral receptor-binding domain (RBD) via its interaction with a cell surface receptor is thought to initiate a cascade of events that lead to refolding of the Env glycoprotein into its stable fusion-active conformation. While the fusion-active conformation of the TM subunit has been described in detail for several retroviruses, little is known about the fusion-competent structure of the retroviral glycoproteins or the molecular events that mediate the transition between the two conformations. By characterizing Env chimeras between the ecotropic and amphotropic murine leukemia virus (MLV) SUs as well as a set of point mutants, we show that alterations of the conformation of the SU glycoprotein strongly elevate Env fusogenicity by disrupting the stability of the Env complex. Compensatory mutations that restored both Env stability and fusion control were also identified, allowing definition of interactions within the Env complex that maintain the stability of the native Env complex. We show that, in the receptor-unbound form, structural interactions between the N terminus of the viral RBD (NTR domain), the proline-rich region (PRR), and the distal part of the C-terminal domain of the SU subunit maintain a conformation of the glycoprotein that is fusion inhibitory. Additionally, we identified mutations that disrupt this fusion-inhibitory conformation and allow fusion activation in the absence of viral receptors, provided that receptor-activated RBD fragments are added in trans during infection. Other mutations were identified that allow fusion activation in the absence of receptors for both the viral glycoprotein and the trans-acting RBD. Finally, we found mutations of the SU that bypass in cis the requirement for the NTR domain in fusion activation. All

  19. Relationship between SU subdomains that regulate the receptor-mediated transition from the native (fusion-inhibited) to the fusion-active conformation of the murine leukemia virus glycoprotein.

    PubMed

    Lavillette, Dimitri; Ruggieri, Alessia; Boson, Bertrand; Maurice, Marielle; Cosset, François-Loïc

    2002-10-01

    Envelope glycoproteins (Env) of retroviruses are trimers of SU (surface) and TM (transmembrane) heterodimers and are expressed on virions in fusion-competent forms that are likely to be metastable. Activation of the viral receptor-binding domain (RBD) via its interaction with a cell surface receptor is thought to initiate a cascade of events that lead to refolding of the Env glycoprotein into its stable fusion-active conformation. While the fusion-active conformation of the TM subunit has been described in detail for several retroviruses, little is known about the fusion-competent structure of the retroviral glycoproteins or the molecular events that mediate the transition between the two conformations. By characterizing Env chimeras between the ecotropic and amphotropic murine leukemia virus (MLV) SUs as well as a set of point mutants, we show that alterations of the conformation of the SU glycoprotein strongly elevate Env fusogenicity by disrupting the stability of the Env complex. Compensatory mutations that restored both Env stability and fusion control were also identified, allowing definition of interactions within the Env complex that maintain the stability of the native Env complex. We show that, in the receptor-unbound form, structural interactions between the N terminus of the viral RBD (NTR domain), the proline-rich region (PRR), and the distal part of the C-terminal domain of the SU subunit maintain a conformation of the glycoprotein that is fusion inhibitory. Additionally, we identified mutations that disrupt this fusion-inhibitory conformation and allow fusion activation in the absence of viral receptors, provided that receptor-activated RBD fragments are added in trans during infection. Other mutations were identified that allow fusion activation in the absence of receptors for both the viral glycoprotein and the trans-acting RBD. Finally, we found mutations of the SU that bypass in cis the requirement for the NTR domain in fusion activation. All

  20. Fusion of platelet-derived growth receptor {beta} to a novel ets-like gene, tel, in chronic myelomonocytic leukemia with t(5;12) chromosomal translocation

    SciTech Connect

    Golub, T.; Barker, G.; Gilliland, D.G.

    1994-09-01

    Chronic myelomonocytic leukemia (CMML) is a myelodysplastic syndrome characterized by abnormal clonal myeloid proliferation, and by progression to acute myelogenous leukemia (AML). A recently recognized subgroup of CMML has a t(5;12) (q33;p13) balanced translocation. Fluorescence in situ hybridization (FISH) localized the translocation breakpoint near the CSF1 receptor (CSF1R) locus on chromosome 5q. Pulsed-field gel electrophoresis confirmed rearrangements near CSF1R, but involvement of CSF1R itself was excluded. Southern blotting showed a rearrangement within the closely linked PDGF receptor {beta} (PDGFR{beta}) gene. Ribonuclease protection assays localized the translocation breakpoint to nucleotide 1766 in PDGFR{beta} RNA. Anchored PCR was used to identify the chromosome 12 fusion partner, a novel ets-like protein, tel. Tel contains a highly conserved carboxy terminal ets-like DNA-binding domain, and an amino terminal domain with a predicted helix-loop-helix (HLH) secondary structure. The consequence of the t(5;12) translocation is fusion of the tel HLH domain to the PDGFR{beta} transmembrane and tyrosine kinase domains. The tel HLH domain may contribute a dimerization motif which serves to constitutively activate PDGFR{beta} tyrosine kinase activity. The tel-PDGFR{beta} fusion demonstrates the oncogenic potential of PDGFR{beta}, and may provide a paradigm for early events in the pathogenesis of AML.

  1. Nanoluciferase as a novel quantitative protein fusion tag: Application for overexpression and bioluminescent receptor-binding assays of human leukemia inhibitory factor.

    PubMed

    He, Sheng-Xiang; Song, Ge; Shi, Jia-Ping; Guo, Yu-Qi; Guo, Zhan-Yun

    2014-11-01

    Nanoluciferase (NanoLuc) is a newly developed small luciferase reporter with the brightest bioluminescence reported to date. In the present work, we developed NanoLuc as a novel quantitative protein fusion tag for efficient overexpression in Escherichia coli and ultrasensitive bioluminescent assays using human leukemia inhibitory factor (LIF) as a model protein. LIF is an interleukin 6 family cytokine that elicits pleiotropic effects on a diverse range of cells by activating a heterodimeric LIFR/gp130 receptor. Recombinant preparation of the biologically active LIF protein is quite difficult due to its hydrophobic nature and three disulfide bonds. Using the novel NanoLuc-fusion approach, soluble 6×His-NanoLuc-LIF fusion protein was efficiently overexpressed in E. coli and enzymatically converted to monomeric mature LIF. Both the mature LIF and the NanoLuc-fused LIF had high biological activities in a leukemia M1 cell proliferation inhibition assay and in a STAT3 signaling activation assay. The NanoLuc-fused LIF retained high binding affinities with the overexpressed LIFR (Kd = 1.4 ± 0.4 nM, n = 3), the overexpressed LIFR/gp130 (Kd = 115 ± 8 pM, n = 3), and the endogenously expressed LIFR/gp130 (Kd = 33.1 ± 3.2 pM, n = 3), with a detection limit of less than 10 receptors per cell. Thus, the novel NanoLuc-fusion strategy not only provided an efficient approach for preparation of recombinant LIF protein but also provided a novel ultrasensitive bioluminescent tracer for ligand-receptor interaction studies. The novel NanoLuc-fusion approach could be extended to other proteins for both efficient sample preparation and various bioluminescent quantitative assays in future studies.

  2. Prognostic and therapeutic role of targetable lesions in B-lineage acute lymphoblastic leukemia without recurrent fusion genes

    PubMed Central

    Fedullo, Anna Lucia; Peragine, Nadia; Gianfelici, Valentina; Piciocchi, Alfonso; Brugnoletti, Fulvia; Di Giacomo, Filomena; Pauselli, Simona; Holmes, Antony B.; Puzzolo, Maria Cristina; Ceglie, Giulia; Apicella, Valerio; Mancini, Marco; te Kronnie, Geertruy; Testi, Anna Maria; Vitale, Antonella; Vignetti, Marco; Guarini, Anna; Rabadan, Raul; Foà, Robin

    2016-01-01

    To shed light into the molecular bases of B-lineage acute lymphoblastic leukemia lacking known fusion transcripts, i.e. BCR-ABL1, ETV6-RUNX1, E2A-PBX1, and MLL rearrangements (B-NEG ALL) and the differences between children, adolescents/young adults (AYA) and adults, we analyzed 168 B-NEG ALLs by genome-wide technologies. This approach showed that B-NEG cases carry 10.5 mutations and 9.1 copy-number aberrations/sample. The most frequently mutated druggable pathways were those pertaining to RAS/RTK (26.8%) and JAK/STAT (12.5%) signaling. In particular, FLT3 and JAK/STAT mutations were detected mainly in AYA and adults, while KRAS and NRAS mutations were more frequent in children. RAS/RTK mutations negatively affected the outcome of AYA and adults, but not that of children. Furthermore, adult B-NEG ALL carrying JAK/STAT mutations had a shorter survival. In vitro experiments showed that FLT3 inhibitors reduced significantly the proliferation of FLT3-mutated primary B-NEG ALL cells. Likewise, PI3K/mTOR inhibitors reduced the proliferation of primary cells harboring RAS and IL7R mutations. These results refine the genetic landscape of B-NEG ALL and suggest that the different distribution of lesions and their prognostic impact might sustain the diverse outcome between children, adults and partly AYA - whose genomic scenario is similar to adults - and open the way to targeted therapeutic strategies. PMID:26883104

  3. Flt3 Does Not Play a Critical Role in Murine Myeloid Leukemias Induced by MLL Fusion Genes

    PubMed Central

    Albouhair, Stéphanie; Morgado, Ester; Lavau, Catherine

    2013-01-01

    Leukemias harboring MLL translocations are frequent in children and adults, and respond poorly to therapies. The receptor tyrosine kinase FLT3 is highly expressed in these leukemias. In vitro studies have shown that pediatric MLL-rearranged ALL cells are sensitive to FLT3 inhibitors and clinical trials are ongoing to measure their therapeutic efficacy. We sought to determine the contribution of Flt3 in the pathogenesis of MLL-rearranged leukemias using a myeloid leukemia mouse model. Bone marrow from Flt3 null mice transduced with MLL-ENL or MLL-CBP was transplanted into host mice and Flt3−/− leukemias were compared to their Flt3 wild type counterparts. Flt3 deficiency did not delay disease onset and had minimal impact on leukemia characteristics. To determine the anti-leukemic effect of FLT3 inhibition we studied the sensitivity of MLL-ENL leukemia cells to the FLT3 inhibitor PKC412 ex vivo. As previously reported for human MLL-rearranged leukemias, murine MLL-ENL leukemia cells with higher Flt3 levels were more sensitive to the cytotoxicity of PKC412. Interestingly, Flt3 deficient leukemia samples also displayed some sensitivity to PKC412. Our findings demonstrate that myeloid leukemias induced by MLL-rearranged genes are not dependent upon Flt3 signaling. They also highlight the discrepancy between the sensitivity of cells to Flt3 inhibition in vitro and the lack of contribution of Flt3 to the pathogenesis of MLL-rearranged leukemias in vivo. PMID:23977266

  4. Fusion

    NASA Astrophysics Data System (ADS)

    Herman, Robin

    1990-10-01

    The book abounds with fascinating anecdotes about fusion's rocky path: the spurious claim by Argentine dictator Juan Peron in 1951 that his country had built a working fusion reactor, the rush by the United States to drop secrecy and publicize its fusion work as a propaganda offensive after the Russian success with Sputnik; the fortune Penthouse magazine publisher Bob Guccione sank into an unconventional fusion device, the skepticism that met an assertion by two University of Utah chemists in 1989 that they had created "cold fusion" in a bottle. Aimed at a general audience, the book describes the scientific basis of controlled fusion--the fusing of atomic nuclei, under conditions hotter than the sun, to release energy. Using personal recollections of scientists involved, it traces the history of this little-known international race that began during the Cold War in secret laboratories in the United States, Great Britain and the Soviet Union, and evolved into an astonishingly open collaboration between East and West.

  5. Generation of the AML1-EVI-1 fusion gene in the t(3;21)(q26;q22) causes blastic crisis in chronic myelocytic leukemia.

    PubMed Central

    Mitani, K; Ogawa, S; Tanaka, T; Miyoshi, H; Kurokawa, M; Mano, H; Yazaki, Y; Ohki, M; Hirai, H

    1994-01-01

    The t(3;21)(q26;q22) translocation, which is one of the consistent chromosomal abnormalities found in blastic crisis of chronic myelocytic leukemia (CML), is thought to play an important role in the leukemic progression of CML to an acute blastic crisis phase. The AML1 gene, which is located at the translocation breakpoint of the t(8;21)(q22;q22) translocation found in acute myelocytic leukemia, was also rearranged by the t(3;21)(q26;q22) translocation. Screening of a cDNA library of the t(3;21)-carrying leukemic cell line cells (SKH1) resulted in the isolation of two potentially complete AML1-EVI-1 chimeric cDNAs of 6 kb. Two species of AML1-EVI-1 fusion transcripts of 8.2 and 7.0 kb were detected in SKH1 cells. These cells expressed the 180 kDa AML1-EVI-1 fusion protein containing an N-terminal half of AML1 including a runt homology domain which is fused to the entire zinc finger EVI-1 protein. The AML1-EVI-1 fusion transcript was consistent in all three cases of the t(3;21)-carrying leukemia examined by RNA-based PCR. These findings strongly suggest that the t(3;21) translocation results in the formation of a new class of chimeric transcription factor which could contribute to the leukemic progression of CML through interference with cell growth and differentiation. Images PMID:8313895

  6. Sequence-specific electrochemical detection of double-strand PCR amplicons of PML/RARα fusion gene in acute promyelocytic leukemia.

    PubMed

    Lei, Yun; Feng, Mei-juan; Wang, Kun; Lin, Li-qing; Chen, Yuan-zhong; Lin, Xin-hua

    2013-01-01

    A novel electrochemical method for the sequence-specific detection of double-stranded polymerase chain reaction (PCR) products of PML/RARα fusion gene in acute promyelocytic leukemia (APL) was described in detail. Based on a "sandwich" sensing mode involving a pair of locked nucleic acids probes (capture probe and reporter probe), this DNA sensor exhibited excellent selectivity and specificity. The direct and quantitative analysis of double-stranded complementary was firstly performed by our sensor without the use of alkali, helicase enzymes, or denaturants. Finally, combining PCR technique with electrochemical detection scheme, PCR amplicons (191 bp) of the PML/RARα fusion gene were obtained and rapidly identified with a low detection limit of 79 fmol in the 100-μL hybridization system. The results clearly showed the power of sensor as a promising tool for the sensitive, specific, and portable detection of APL and other diseases.

  7. A comprehensive analysis of breakpoint cluster region-abelson fusion oncogene splice variants in chronic myeloid leukemia and their correlation with disease biology

    PubMed Central

    Iqbal, Zafar

    2014-01-01

    BACKGROUND: BCR-ABL fusion oncogene is a hallmark of Chronic Myeloid Leukemia (CML). It results due to translocation between chromosome 22 and chromosome 9 [t (9; 22)(q34; q11)]. It gives rise to translation of a 210 KDa chimeric protein (p210), leading to enhanced tyrosine kinase activity and activation of leukemogenic pathways, ultimately causing onset of CML. In case of CML, the classic fusions are b2a2 or b3a2, fusing exon 13 (b2) or exon 14 (b3) of BCR, respectively, to exon 2 (a2) of ABL. The type of BCR-ABL transcripts are thought to be have different prognosis and hence useful in clinical decision-making. The frequencies of different fusion oncogenes associated with leukemia can vary in different ethnic groups and geographical regions due to interplay of genetic variation in different ethnic populations, diverse environmental factors and living style. Moreover, earlier relevant studies from our region were carried out in small subset of patients. Therefore, objective of this study was to find out frequencies of different BCR-ABL splice variants in larger subset of CML patients. METHODS: A nested reverse transcriptase polymerase chain reaction (RT-PCR) was established to detect BCR-ABL splice variants in 130 CML patients. Sensitivity of RT-PCR and ability to detect BCR-ABL fusion gene in least possible time was studied. RESULTS: BCR-ABL detection using our optimized RT-PCR protocol could be completed in 8 hours, starting from RNA extraction to Gel electrophoresis. Sensitivity of RT-PCR assay was of the order of 10−6. Out of 130 Pakistani patients, 83 (63.84%) expressed b3a2 while 47 (36.15%) expressed b2a2 transcript. CONCLUSION: Our RT-PCR was proved to be very quick to detect BCR-ABL fusion oncogene in CML patients within one working day. Because of its sensitivity, it can be used to monitor complete molecular response in CML. BCR-ABL RT-PCR and BCR-ABL splice variants frequency in our study differs from other ethnic groups. It shows that ethnic and

  8. Chronic myelogenous leukemia stem and progenitor cells demonstrate chromosomal instability related to repeated breakage-fusion-bridge cycles mediated by increased nonhomologous end joining.

    PubMed

    Chakraborty, Sujata; Stark, Jeremy M; Sun, Can-Lan; Modi, Hardik; Chen, WenYong; O'Connor, Timothy R; Forman, Stephen J; Bhatia, Smita; Bhatia, Ravi

    2012-06-28

    Chromosomal aberrations are an important consequence of genotoxic exposure and contribute to pathogenesis and progression of several malignancies. We investigated the susceptibility to chromosomal aberrations in chronic myelogenous leukemia (CML) progenitors after exposure to ionizing radiation. In normal progenitors, ionizing radiation induced both stable and unstable chromosomal lesions, but only stable aberrations persisted after multiple divisions. In contrast, radiation of chronic phase CML progenitors resulted in enhanced generation of unstable lesions that persisted after multiple divisions. CML progenitors demonstrated active cell cycle checkpoints and increased nonhomologous end joining DNA repair, suggesting that persistence of unstable aberrations was the result of continued generation of these lesions. CML progenitors demonstrated enhanced susceptibility to repeated cycles of chromosome damage, repair, and damage through a breakage-fusion-bridge mechanism. Perpetuation of breakage-fusion-bridge cycles in CML progenitors was mediated by classic nonhomologous end joining repair. These studies reveal a previously unrecognized mechanism of chromosomal instability in leukemia progenitors because of continued generation of unstable chromosomal lesions through repeated cycles of breakage and repair of such lesions.

  9. Fusion of dendritic cells and CD34+CD38- acute myeloid leukemia (AML) cells potentiates targeting AML-initiating cells by specific CTL induction.

    PubMed

    Lei, Zhang; Zhang, Gui-Mei; Hong, Mei; Feng, Zuo-Hua; Huang, Bo

    2009-05-01

    Distinct leukemia-initiating cells (L-ICs) represent a critical target for therapeutic intervention of acute myeloid leukemia (AML). A potential strategy to eradicate L-ICs is to generate L-IC-specific cytotoxic T lymphocytes (CTLs). However, owing to rarity and immortality of L-ICs, it is difficult for antigen-presenting cells to capture L-ICs for specific antigen presentation. Here, we report a novel approach by fusing allogeneic dendritic cells (DCs) and CD34CD38 AML progenitor cells, through which specific CTLs were effectively induced, leading to the cytolysis to AML-initiating cells. Fusion of either DC/CD34CD38 AML cell or DC/CD34 AML cell could effectively induce the proliferation and activation of CTLs. However, only the former CTLs could effectively attack AML progenitor cells, and result in the unkilled progenitor/initiating cells losing the abilities of active proliferation in vitro and engraftment in NOD-SCID mice. These findings suggest that AML progenitor/initiating cell-specific CTLs may be generated based on allogeneic DC/progenitor cell fusion strategy; the induced CTLs may potentially eradicate AML by targeting L-ICs directly or indirectly.

  10. The clinical significance of monitoring the expression of the SIL-TAL1 fusion gene in T-cell acute lymphoblastic leukemia after allogeneic hematopoietic stem cell transplantation.

    PubMed

    Zhao, X; Hong, Y; Qin, Y; Xu, Y; Chang, Y; Wang, Y; Zhang, X; Xu, L; Huang, X

    2017-07-24

    SIL-TAL1 rearrangement is common in T-cell acute lymphoblastic leukemia (T-ALL). However, whether this fusion gene might be used as a reliable marker of minimal residual disease (MRD) following allogeneic stem cell transplantation (allo-HSCT) remains unknown METHODS: The clinical data of consecutive 29 patients with T-ALL who received allo-HSCT were collected. Their MRD were evaluated by SIL-TAL1, Wilms' tumor 1 (WT1) expression, and the leukemia-associated immunophenotype (LAIP) . The median follow-up was 354 days (71-2111 days). Of the enrolled patients, 14 (87.5%) patients died of leukemia relapse. A total of 15 (51.7%) patients experienced relapse at a median of 90 days (60-540 days) after transplantation. The SIL-TAL1 expression of 16 patients converted from negative prior to transplantation to positive at 77 days (30-281 days) following transplantation; furthermore, 15 (93.8%) of them eventually experienced relapse. In the 15 relapsed patients, 13 (86.7%) had increased SIL-TAL1 expression levels 30 days (11-220 days) earlier than the hematological relapse and the detection of abnormal WT1 and LAIP. We are the first to demonstrate the reliability of the SIL-TAL1 fusion gene as a good MRD marker for patients with T-ALL after allo-HSCT. © 2017 John Wiley & Sons Ltd.

  11. The Functional Interplay Between the t(9;22)-Associated Fusion Proteins BCR/ABL and ABL/BCR in Philadelphia Chromosome-Positive Acute Lymphatic Leukemia

    PubMed Central

    Rafiei, Anahita; Mian, Afsar Ali; Döring, Claudia; Metodieva, Anna; Oancea, Claudia; Thalheimer, Frederic B.; Hansmann, Martin Leo; Ottmann, Oliver Gerhard; Ruthardt, Martin

    2015-01-01

    The hallmark of Philadelphia chromosome positive (Ph+) leukemia is the BCR/ABL kinase, which is successfully targeted by selective ATP competitors. However, inhibition of BCR/ABL alone is unable to eradicate Ph+ leukemia. The t(9;22) is a reciprocal translocation which encodes not only for the der22 (Philadelphia chromosome) related BCR/ABL, but also for der9 related ABL/BCR fusion proteins, which can be detected in 65% of patients with chronic myeloid leukemia (CML) and 100% of patients with Ph+ acute lymphatic leukemia (ALL). ABL/BCRs are oncogenes able to influence the lineage commitment of hematopoietic progenitors. Aim of this study was to further disclose the role of p96ABL/BCR for the pathogenesis of Ph+ ALL. The co-expression of p96ABL/BCR enhanced the kinase activity and as a consequence, the transformation potential of p185BCR/ABL. Targeting p96ABL/BCR by RNAi inhibited growth of Ph+ ALL cell lines and Ph+ ALL patient-derived long-term cultures (PD-LTCs). Our in vitro and in vivo stem cell studies further revealed a functional hierarchy of p96ABL/BCR and p185BCR/ABL in hematopoietic stem cells. Co-expression of p96ABL/BCR abolished the capacity of p185BCR/ABL to induce a CML-like disease and led to the induction of ALL. Taken together our here presented data reveal an important role of p96ABL/BCR for the pathogenesis of Ph+ ALL. PMID:25919613

  12. The FIP1L1-PDGFRA fusion gene cooperates with IL-5 to induce murine hypereosinophilic syndrome (HES)/chronic eosinophilic leukemia (CEL)-like disease.

    PubMed

    Yamada, Yoshiyuki; Rothenberg, Marc E; Lee, Andrew W; Akei, Hiroko Saito; Brandt, Eric B; Williams, David A; Cancelas, Jose A

    2006-05-15

    Dysregulated tyrosine kinase activity by the Fip1-like1 (FIP1L1)-platelet-derived growth factor receptor alpha (PDGFRA) (F/P) fusion gene has been identified as a cause of clonal hypereosinophilic syndrome (HES), called F/P-positive chronic eosinophilic leukemia (CEL) in humans. However, transplantation of F/P-transduced hematopoietic stem cells/progenitors (F/P(+) HSCs/Ps) into mice results in a chronic myelogenous leukemia-like disease, which does not resemble HES. Because a subgroup of patients with HES show T-cell-dependent interleukin-5 (IL-5) overexpression, we determined if expression of the F/P fusion gene in the presence of transgenic T-cell IL-5 overexpression in mice induces HES-like disease. Mice that received a transplant of CD2-IL-5-transgenic F/P(+) HSC/Ps (IL-5Tg-F/P) developed intense leukocytosis, strikingly high eosinophilia, and eosinophilic infiltration of nonhematopoietic as well as hematopoietic tissues, a phenotype resembling human HES. The disease phenotype was transferable to secondary transplant recipients of a high cell dose, suggesting involvement of a short-term repopulating stem cell or an early myeloid progenitor. Induction of significant eosinophilia was specific for F/P since expression of another fusion oncogene, p210-BCR/ABL, in the presence of IL-5 overexpression was characterized by a significantly lower eosinophilia than IL-5Tg-F/P recipients. These results suggest that F/P is not sufficient to induce a HES/CEL-like disease but requires a second event associated with IL-5 overexpression.

  13. Targeting recruitment of disruptor of telomeric silencing 1-like (DOT1L): characterizing the interactions between DOT1L and mixed lineage leukemia (MLL) fusion proteins.

    PubMed

    Shen, Chenxi; Jo, Stephanie Y; Liao, Chenzhong; Hess, Jay L; Nikolovska-Coleska, Zaneta

    2013-10-18

    The MLL fusion proteins, AF9 and ENL, activate target genes in part via recruitment of the histone methyltransferase DOT1L (disruptor of telomeric silencing 1-like). Here we report biochemical, biophysical, and functional characterization of the interaction between DOT1L and MLL fusion proteins, AF9/ENL. The AF9/ENL-binding site in human DOT1L was mapped, and the interaction site was identified to a 10-amino acid region (DOT1L865-874). This region is highly conserved in DOT1L from a variety of species. Alanine scanning mutagenesis analysis shows that four conserved hydrophobic residues from the identified binding motif are essential for the interactions with AF9/ENL. Binding studies demonstrate that the entire intact C-terminal domain of AF9/ENL is required for optimal interaction with DOT1L. Functional studies show that the mapped AF9/ENL interacting site is essential for immortalization by MLL-AF9, indicating that DOT1L interaction with MLL-AF9 and its recruitment are required for transformation by MLL-AF9. These results strongly suggest that disruption of interaction between DOT1L and AF9/ENL is a promising therapeutic strategy with potentially fewer adverse effects than enzymatic inhibition of DOT1L for MLL fusion protein-associated leukemia.

  14. Evaluation of a new flow cytometry based method for detection of BCR-ABL1 fusion protein in chronic myeloid leukemia.

    PubMed

    Dasgupta, Swati; Ray, Ujjal K; Mitra, Arpita Ghosh; Bhattacharyya, Deboshree M; Mukhopadhyay, Ashis; Das, Priyabrata; Gangopadhyay, Sudeshna; Roy, Sudip; Mukhopadhyay, Soma

    2017-06-01

    Philadelphia chromosome, a hallmark of chronic myeloid leukemia (CML), plays a key role in disease pathogenesis. It reflects a balanced reciprocal translocation between long arms of chromosomes 9 and 22 involving BCR and ABL1 genes, respectively. An accurate and reliable detection of BCR-ABL fusion gene is necessary for the diagnosis and monitoring of CML. Previously, many technologies, most of which are laborious and time consuming, have been developed to detect BCR-ABL chimeric gene or chromosome. A new flow cytometric immunobead assay was used for detection of BCR-ABL fusion proteins and applicability, sensitivity, reliability, efficacy and rapidity of this method was evaluated. From February 2009 to January 2014, a total 648 CML patients were investigated for the status of BCR-ABL1 protein. Among them, 83 patients were enrolled for comparative study of BCR-ABL1 positivity by three routinely used procedures like karyotyping, and quantitative real time PCR (RT-PCR) as well as immunobead flow cytometry assay. BCR-ABL protein analysis was found consistent, more sensitive (17% greater sensitivity) and reliable than the conventional cytogenetics, as flow cytometry showed 95% concordance rate to RT-PCR. BCR-ABL fusion protein assay using a new flow cytometric immunobead might be useful in the diagnosis and monitoring CML patients.

  15. Effects on differentiation by the promyelocytic leukemia PML/RARalpha protein depend on the fusion of the PML protein dimerization and RARalpha DNA binding domains.

    PubMed Central

    Grignani, F; Testa, U; Rogaia, D; Ferrucci, P F; Samoggia, P; Pinto, A; Aldinucci, D; Gelmetti, V; Fagioli, M; Alcalay, M; Seeler, J; Grignani, F; Nicoletti, I; Peschle, C; Pelicci, P G

    1996-01-01

    The block of terminal differentiation is a prominent feature of acute promyelocytic leukemia (APL) and its release by retinoic acid correlates with disease remission. Expression of the APL-specific PML/RARalpha fusion protein in hematopoietic precursor cell lines blocks terminal differentiation, suggesting that PML/ RARalpha may have the same activity in APL blasts. We expressed different PML/RARalpha mutants in U937 and TF-1 cells and demonstrated that the integrity of the PML protein dimerization and RARalpha DNA binding domains is crucial for the differentiation block induced by PML/RARalpha, and that these domains exert their functions only within the context of the fusion protein. Analysis of the in vivo dimerization and cell localization properties of the PML/RARalpha mutants revealed that PML/RARalpha--PML and PML/RARalpha--RXR heterodimers are not necessary for PML/RARalpha activity on differentiation. We propose that a crucial mechanism underlying PML/RARalpha oncogenic activity is the deregulation of a transcription factor, RARalpha, through its fusion with the dimerization interface of another nuclear protein, PML. Images PMID:8890168

  16. Virus-induced aggregates in infected cells.

    PubMed

    Moshe, Adi; Gorovits, Rena

    2012-10-17

    During infection, many viruses induce cellular remodeling, resulting in the formation of insoluble aggregates/inclusions, usually containing viral structural proteins. Identification of aggregates has become a useful diagnostic tool for certain viral infections. There is wide variety of viral aggregates, which differ by their location, size, content and putative function. The role of aggregation in the context of a specific virus is often poorly understood, especially in the case of plant viruses. The aggregates are utilized by viruses to house a large complex of proteins of both viral and host origin to promote virus replication, translation, intra- and intercellular transportation. Aggregated structures may protect viral functional complexes from the cellular degradation machinery. Alternatively, the activation of host defense mechanisms may involve sequestration of virus components in aggregates, followed by their neutralization as toxic for the host cell. The diversity of virus-induced aggregates in mammalian and plant cells is the subject of this review.

  17. An unusual case of splenomegaly and increased lactate dehydrogenase heralding acute myeloid leukemia with eosinophilia and RUNX1–MECOM fusion transcripts

    PubMed Central

    Forghieri, Fabio; Bigliardi, Sara; Morselli, Monica; Potenza, Leonardo; Fantuzzi, Valeria; Faglioni, Laura; Nasillo, Vincenzo; Messerotti, Andrea; Paolini, Ambra; Luppi, Mario

    2014-01-01

    We report the first case of acute myeloid leukemia (AML) with RUNX1–MECOM fusion transcripts, showing marked eosinophilia. A 63-year old man admitted in August 2013, had previously been observed in April 2013, because of persisting homogeneous splenomegaly and increased LDH, which were initially attributed to both minor β-thalassemia and previous acute myocardial infarction. However, based upon the retrospective analysis of clinical features combined with the documentation of both JAK2 V617F and c-KIT D816V mutations at AML diagnosis, an aggressive leukemic transformation with eosinophilia of a previously unrecognized myeloproliferative neoplasm, rather than the occurrence of de novo AML, may be hypothesized. PMID:25379409

  18. Synergistic effects of selective inhibitors targeting the PI3K/AKT/mTOR pathway or NUP214-ABL1 fusion protein in human Acute Lymphoblastic Leukemia

    PubMed Central

    Martelli, Alberto M.; Zauli, Giorgio; Milani, Daniela; McCubrey, James A.; Capitani, Silvano; Neri, Luca M.

    2016-01-01

    Philadelphia chromosome-positive (Ph+) Acute Lymphoblastic Leukemia (ALL) accounts for 25–30% of adult ALL and its incidence increases with age in adults >40 years old. Irrespective of age, the ABL1 fusion genes are markers of poor prognosis and amplification of the NUP214-ABL1 oncogene can be detected mainly in patients with T-ALL. T cell malignancies harboring the ABL1 fusion genes are sensitive to many cytotoxic agents, but up to date complete remissions have not been achieved. The PI3K/Akt/mTOR signaling pathway is often activated in leukemias and plays a crucial role in leukemogenesis. We analyzed the effects of three BCR-ABL1 tyrosine kinase inhibitors (TKIs), alone and in combination with a panel of selective PI3K/Akt/mTOR inhibitors, on three NUP214-ABL1 positive T-ALL cell lines that also displayed PI3K/Akt/mTOR activation. Cells were sensitive to anti BCR-ABL1 TKIs Imatinib, Nilotinib and GZD824, that specifically targeted the ABL1 fusion protein, but not the PI3K/Akt/mTOR axis. Four drugs against the PI3K/Akt/mTOR cascade, GSK690693, NVP-BGT226, ZSTK474 and Torin-2, showed marked cytotoxic effects on T-leukemic cells, without affecting the NUP214-ABL1 kinase and related pathway. Dephosphorylation of pAkt and pS6 showed the cytotoxicity of these compounds. Either single or combined administration of drugs against the different targets displayed inhibition of cellular viability associated with a concentration-dependent induction of apoptosis, cell cycle arrest in G0/G1 phase and autophagy, having the combined treatments a significant synergistic cytotoxic effect. Co-targeting NUP214-ABL1 fusion gene and PI3K/Akt/mTOR signaling pathway could represent a new and effective pharmacological strategy to improve the outcome in NUP214-ABL1 positive T-ALL. PMID:27821800

  19. Leukemia-Associated Nup214 Fusion Proteins Disturb the XPO1-Mediated Nuclear-Cytoplasmic Transport Pathway and Thereby the NF-κB Signaling Pathway

    PubMed Central

    Cigdem, Sadik; Okuwaki, Mitsuru; Nagata, Kyosuke

    2016-01-01

    Nuclear-cytoplasmic transport through nuclear pore complexes is mediated by nuclear transport receptors. Previous reports have suggested that aberrant nuclear-cytoplasmic transport due to mutations or overexpression of nuclear pore complexes and nuclear transport receptors is closely linked to diseases. Nup214, a component of nuclear pore complexes, has been found as chimeric fusion proteins in leukemia. Among various Nup214 fusion proteins, SET-Nup214 and DEK-Nup214 have been shown to be engaged in tumorigenesis, but their oncogenic mechanisms remain unclear. In this study, we examined the functions of the Nup214 fusion proteins by focusing on their effects on nuclear-cytoplasmic transport. We found that SET-Nup214 and DEK-Nup214 interact with exportin-1 (XPO1)/CRM1 and nuclear RNA export factor 1 (NXF1)/TAP, which mediate leucine-rich nuclear export signal (NES)-dependent protein export and mRNA export, respectively. SET-Nup214 and DEK-Nup214 decreased the XPO1-mediated nuclear export of NES proteins such as cyclin B and proteins involved in the NF-κB signaling pathway by tethering XPO1 onto nuclear dots where Nup214 fusion proteins are localized. We also demonstrated that SET-Nup214 and DEK-Nup214 expression inhibited NF-κB-mediated transcription by abnormal tethering of the complex containing p65 and its inhibitor, IκB, in the nucleus. These results suggest that SET-Nup214 and DEK-Nup214 perturb the regulation of gene expression through alteration of the nuclear-cytoplasmic transport system. PMID:27114368

  20. Leukemia-Associated Nup214 Fusion Proteins Disturb the XPO1-Mediated Nuclear-Cytoplasmic Transport Pathway and Thereby the NF-κB Signaling Pathway.

    PubMed

    Saito, Shoko; Cigdem, Sadik; Okuwaki, Mitsuru; Nagata, Kyosuke

    2016-07-01

    Nuclear-cytoplasmic transport through nuclear pore complexes is mediated by nuclear transport receptors. Previous reports have suggested that aberrant nuclear-cytoplasmic transport due to mutations or overexpression of nuclear pore complexes and nuclear transport receptors is closely linked to diseases. Nup214, a component of nuclear pore complexes, has been found as chimeric fusion proteins in leukemia. Among various Nup214 fusion proteins, SET-Nup214 and DEK-Nup214 have been shown to be engaged in tumorigenesis, but their oncogenic mechanisms remain unclear. In this study, we examined the functions of the Nup214 fusion proteins by focusing on their effects on nuclear-cytoplasmic transport. We found that SET-Nup214 and DEK-Nup214 interact with exportin-1 (XPO1)/CRM1 and nuclear RNA export factor 1 (NXF1)/TAP, which mediate leucine-rich nuclear export signal (NES)-dependent protein export and mRNA export, respectively. SET-Nup214 and DEK-Nup214 decreased the XPO1-mediated nuclear export of NES proteins such as cyclin B and proteins involved in the NF-κB signaling pathway by tethering XPO1 onto nuclear dots where Nup214 fusion proteins are localized. We also demonstrated that SET-Nup214 and DEK-Nup214 expression inhibited NF-κB-mediated transcription by abnormal tethering of the complex containing p65 and its inhibitor, IκB, in the nucleus. These results suggest that SET-Nup214 and DEK-Nup214 perturb the regulation of gene expression through alteration of the nuclear-cytoplasmic transport system. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  1. Developmental origins and impact of BCR-ABL1 fusion and IKZF1 deletions in monozygotic twins with Ph+ acute lymphoblastic leukemia

    PubMed Central

    van Delft, Frederik W.; Lo Nigro, Luca; Ford, Anthony M.; Score, Joannah; Iacobucci, Ilaria; Mirabile, Elena; Taj, Mary; Colman, Susan M.; Biondi, Andrea

    2011-01-01

    The timing and developmental sequence of events for BCR-ABL1+ acute lymphoblastic leukemia (ALL), usually associated with IKAROS (IKZF1) deletions, are unknown. We assessed the status of BCR-ABL1 and IKZF1 genes in 2 pairs of monozygotic twins, one pair concordant, the other discordant for Philadelphia chromosome positive (Ph+) ALL. The twin pair concordant for ALL shared identical BCR-ABL1 genomic sequence indicative of monoclonal, in utero origin. One twin had IKZF1 deletion and died after transplantation. The other twin had hyperdiploidy, no IKZF1 deletion, and is still in remission 8 years after transplantation. In the twin pair discordant for ALL, neonatal blood spots from both twins harbored the same clonotypic BCR-ABL1 sequence. Low level BCR-ABL1+ cells were present in the healthy co-twin but lacked the IKZF1 deletion present in the other twin's leukemic cells. The twin with ALL relapsed and died after transplantation. The co-twin remains healthy and leukemia free. These data show that in childhood Ph+ ALL, BCR-ABL1 gene fusion can be a prenatal and possibly initiating genetic event. In the absence of additional, secondary changes, the leukemic clone remains clinically silent. IKZF1 is a secondary and probable postnatal mutation in these cases, and as a recurrent but alternative copy number change is associated with poor prognosis. PMID:21960589

  2. The AML1-ETO fusion gene and the FLT3 length mutation collaborate in inducing acute leukemia in mice

    PubMed Central

    Schessl, Christina; Rawat, Vijay P.S.; Cusan, Monica; Deshpande, Aniruddha; Kohl, Tobias M.; Rosten, Patricia M.; Spiekermann, Karsten; Humphries, R. Keith; Schnittger, Susanne; Kern, Wolfgang; Hiddemann, Wolfgang; Quintanilla-Martinez, Leticia; Bohlander, Stefan K.; Feuring-Buske, Michaela; Buske, Christian

    2005-01-01

    The molecular characterization of leukemia has demonstrated that genetic alterations in the leukemic clone frequently fall into 2 classes, those affecting transcription factors (e.g., AML1-ETO) and mutations affecting genes involved in signal transduction (e.g., activating mutations of FLT3 and KIT). This finding has favored a model of leukemogenesis in which the collaboration of these 2 classes of genetic alterations is necessary for the malignant transformation of hematopoietic progenitor cells. The model is supported by experimental data indicating that AML1-ETO and FLT3 length mutation (FLT3-LM), 2 of the most frequent genetic alterations in AML, are both insufficient on their own to cause leukemia in animal models. Here we report that AML1-ETO collaborates with FLT3-LM in inducing acute leukemia in a murine BM transplantation model. Moreover, in a series of 135 patients with AML1-ETO–positive AML, the most frequently identified class of additional mutations affected genes involved in signal transduction pathways including FLT3-LM or mutations of KIT and NRAS. These data support the concept of oncogenic cooperation between AML1-ETO and a class of activating mutations, recurrently found in patients with t(8;21), and provide a rationale for therapies targeting signal transduction pathways in AML1-ETO–positive leukemias. PMID:16025155

  3. Flow Cytometric Immunobead Assay for Detection of BCR-ABL1 Fusion Proteins in Chronic Myleoid Leukemia: Comparison with FISH and PCR Techniques.

    PubMed

    Recchia, Anna Grazia; Caruso, Nadia; Bossio, Sabrina; Pellicanò, Mariavaleria; De Stefano, Laura; Franzese, Stefania; Palummo, Angela; Abbadessa, Vincenzo; Lucia, Eugenio; Gentile, Massimo; Vigna, Ernesto; Caracciolo, Clementina; Agostino, Antolino; Galimberti, Sara; Levato, Luciano; Stagno, Fabio; Molica, Stefano; Martino, Bruno; Vigneri, Paolo; Di Raimondo, Francesco; Morabito, Fortunato

    2015-01-01

    Chronic Myeloid Leukemia (CML) is characterized by a balanced translocation juxtaposing the Abelson (ABL) and breakpoint cluster region (BCR) genes. The resulting BCR-ABL1 oncogene leads to increased proliferation and survival of leukemic cells. Successful treatment of CML has been accompanied by steady improvements in our capacity to accurately and sensitively monitor therapy response. Currently, measurement of BCR-ABL1 mRNA transcript levels by real-time quantitative PCR (RQ-PCR) defines critical response endpoints. An antibody-based technique for BCR-ABL1 protein recognition could be an attractive alternative to RQ-PCR. To date, there have been no studies evaluating whether flow-cytometry based assays could be of clinical utility in evaluating residual disease in CML patients. Here we describe a flow-cytometry assay that detects the presence of BCR-ABL1 fusion proteins in CML lysates to determine the applicability, reliability, and specificity of this method for both diagnosis and monitoring of CML patients for initial response to therapy. We show that: i) CML can be properly diagnosed at onset, (ii) follow-up assessments show detectable fusion protein (i.e. relative mean fluorescent intensity, rMFI%>1) when BCR-ABL1IS transcripts are between 1-10%, and (iii) rMFI% levels predict CCyR as defined by FISH analysis. Overall, the FCBA assay is a rapid technique, fully translatable to the routine management of CML patients.

  4. Coexistence of iAMP21 and ETV6-RUNX1 fusion in an adolescent with B cell acute lymphoblastic leukemia: literature review of six additional cases.

    PubMed

    Gu, Jun; Reynolds, Alexandra; Fang, Lianghua; DeGraffenreid, Corrie; Sterns, Kenneth; Patel, Keyur P; Medeiros, L Jeffrey; Lin, Pei; Lu, Xinyan

    2016-01-01

    Intrachromosomal amplification of chromosome 21 (iAMP21) results from breakage-fusion-bridge cycles and chromothripsis is a distinct marker of a subgroup of B cell acute lymphoblastic leukemia (B-ALL) cases associated with a poor prognosis. iAMP21 accounts for 2% of pediatric B-ALL and occurs predominantly in older children or adolescents. ETV6-RUNX1 fusion, resulting from t(12;21)(p13;q22), is associated with an excellent outcome in younger children with B-ALL. Coexistence of iAMP21 with ETV6-RUNX1 fusion is extremely rare with limited clinical information available. We report the case of an 18-year old Caucasian man diagnosed with ETV6-RUNX1 fusion positive B-ALL. He was treated with intensive chemotherapy and achieved remission for 6 months before relapse, 15 months after the initial diagnosis. G-band karyotyping and Fluorescence in situ hybridization (FISH) analyses performed on bone marrow revealed complex abnormalities: 41,X,-Y,der(3)t(3;20)(p11.2;q11.2),-4,t(5;22)(q32;q11.2),del(9)(p13),dic(9;17)(p13;p11.2),t(12;21)(p13;q22),der(14)t(14;17)(p11.2;q11.2),der(17;22)(q11.2;q11.2),-20,add(21)(q22),-22[4]/46,XY[15] with an iAMP21 and an ETV6-RUNX1. Additional molecular studies confirmed ETV6-RUNX1 fusion and with a TP53 mutation. High-resolution single nucleotide polymorphism microarray (SNP array) revealed the iAMP21 to be chromothripsis of 21q and subsequent metaphase FISH further delineated complex genomic aberrations. Although the patient received intensive chemotherapy with allogenic stem cell transplant, he died 26 months after initial diagnosis. We searched the literature and identified six cases showing coexisting iAMP21 and ETV6-RUNX1. The median age for these six patients was 10 years (range, 2-18) and males predominated. The median overall survival (OS) was 28 months. Patients with B-ALL associated with both iAMP21 and ETV6-RUNX1 tend to be older children or adolescents and have a poor prognosis.

  5. Space-Time Clustering of Childhood Leukemia: Evidence of an Association with ETV6-RUNX1 (TEL-AML1) Fusion

    PubMed Central

    Lupatsch, Judith E.; Niggli, Felix; Egger, Matthias; Kuehni, Claudia E.; Spycher, Ben D.

    2017-01-01

    Background Many studies have observed space-time clustering of childhood leukemia (CL) yet few have attempted to elicit etiological clues from such clustering. We recently reported space-time clustering of CL around birth, and now aim to generate etiological hypotheses by comparing clustered and nonclustered cases. We also investigated whether the clustering resulted from many small aggregations of cases or from a few larger clusters. Methods We identified cases of persons born and diagnosed between 1985 and 2014 at age 0–15 years from the Swiss Childhood Cancer Registry. We determined spatial and temporal lags that maximized evidence of clustering based on the Knox test and classified cases born within these lags from another case as clustered. Using logistic regression adjusted for child population density, we determined whether clustering status was associated with age at diagnosis, immunophenotype, cytogenetic subtype, perinatal and socioeconomic characteristics, and pollution sources. Results Analyses included 1,282 cases of which 242 were clustered (born within 1 km and 2 years from another case). Of all investigated characteristics only the t(12;21)(p13;q22) translocation (resulting in ETV6-RUNX1 fusion) differed significantly in prevalence between clustered and nonclustered cases (40% and 25%, respectively; adjusted OR 2.54 [1.52–4.23]; p = 0.003). Spatio-temporal clustering was driven by an excess of aggregations of two or three children rather than by a few large clusters. Conclusion Our findings suggest ETV6-RUNX1 is associated with space-time clustering of CL and are consistent with an infection interacting with that oncogene in early life leading to clinical leukemia. PMID:28129329

  6. Space-Time Clustering of Childhood Leukemia: Evidence of an Association with ETV6-RUNX1 (TEL-AML1) Fusion.

    PubMed

    Kreis, Christian; Lupatsch, Judith E; Niggli, Felix; Egger, Matthias; Kuehni, Claudia E; Spycher, Ben D

    2017-01-01

    Many studies have observed space-time clustering of childhood leukemia (CL) yet few have attempted to elicit etiological clues from such clustering. We recently reported space-time clustering of CL around birth, and now aim to generate etiological hypotheses by comparing clustered and nonclustered cases. We also investigated whether the clustering resulted from many small aggregations of cases or from a few larger clusters. We identified cases of persons born and diagnosed between 1985 and 2014 at age 0-15 years from the Swiss Childhood Cancer Registry. We determined spatial and temporal lags that maximized evidence of clustering based on the Knox test and classified cases born within these lags from another case as clustered. Using logistic regression adjusted for child population density, we determined whether clustering status was associated with age at diagnosis, immunophenotype, cytogenetic subtype, perinatal and socioeconomic characteristics, and pollution sources. Analyses included 1,282 cases of which 242 were clustered (born within 1 km and 2 years from another case). Of all investigated characteristics only the t(12;21)(p13;q22) translocation (resulting in ETV6-RUNX1 fusion) differed significantly in prevalence between clustered and nonclustered cases (40% and 25%, respectively; adjusted OR 2.54 [1.52-4.23]; p = 0.003). Spatio-temporal clustering was driven by an excess of aggregations of two or three children rather than by a few large clusters. Our findings suggest ETV6-RUNX1 is associated with space-time clustering of CL and are consistent with an infection interacting with that oncogene in early life leading to clinical leukemia.

  7. EP300-ZNF384 fusion gene product up-regulates GATA3 gene expression and induces hematopoietic stem cell gene expression signature in B-cell precursor acute lymphoblastic leukemia cells.

    PubMed

    Yaguchi, Akinori; Ishibashi, Takeshi; Terada, Kazuki; Ueno-Yokohata, Hitomi; Saito, Yuya; Fujimura, Junya; Shimizu, Toshiaki; Ohki, Kentaro; Manabe, Atsushi; Kiyokawa, Nobutaka

    2017-04-04

    ZNF384-related fusion genes are associated with a distinct subgroup of B-cell precursor acute lymphoblastic leukemias in childhood, with a frequency of approximately 3-4%. We previously identified a novel EP300-ZNF384 fusion gene. Patients with the ZNF384-related fusion gene exhibit a hematopoietic stem cell (HSC) gene expression signature and characteristic immunophenotype with negative or low expression of CD10 and aberrant expression of myeloid antigens, such as CD33 and CD13. However, the molecular basis of this pathogenesis remains completely unknown. In the present study, we examined the biological effects of EP300-ZNF384 expression induced by retrovirus-mediated gene transduction in an REH B-cell precursor acute lymphoblastic leukemia cell line, and observed the acquisition of the HSC gene expression signature and an up-regulation of GATA3 gene expression, as assessed by microarray analysis. In contrast, the gene expression profile induced by wild-type ZNF384 in REH cells was significantly different from that by EP300-ZNF384 expression. Together with the results of reporter assays, which revealed the enhancement of GATA3-promoter activity by EP300-ZNF384 expression, these findings suggest that EP300-ZNF384 mediates GATA3 gene expression and may be involved in the acquisition of the HSC gene expression signature and characteristic immunophenotype in B-cell precursor acute lymphoblastic leukemia cells.

  8. Virus-induced immunosuppression in chickens.

    PubMed

    Sharma, J M; Karaca, K; Pertile, T

    1994-07-01

    Reovirus and infectious bursal disease virus are among the naturally occurring viruses that cause immunosuppression in chickens. Both viruses cause necrotic lesions in the bursa of Fabricius and may destroy B cells. This may explain their ability to cause humoral immune suppression. The mechanism(s) of virus-induced suppression of cellular immunity is not well understood. Both viruses inhibit the mitogenic response of T cells in chickens. We have noted that this inhibition may be mediated by inhibitory cytokines such as transforming growth factor-beta and nitric oxide produced by activated macrophages. Preliminary studies have indicated that pretreatment of chickens with an immunomodulator, acemannan, reduced the reovirus-induced inhibition of T cells.

  9. Clinical outcome and monitoring of minimal residual disease in patients with acute lymphoblastic leukemia expressing the MLL/ENL fusion gene.

    PubMed

    Elia, Loredana; Grammatico, Sara; Paoloni, Francesca; Vignetti, Marco; Rago, Angela; Cenfra, Natalia; Mecarocci, Sergio; Mancini, Marco; Luciani, Matteo; Di Raimondo, Francesco; Cazzaniga, Giovanni; Matarazzo, Mabel; Moleti, Maria Luisa; Santoro, Lidia; Gaidano, Gianluca; Foà, Robin; Mandelli, Franco; Cimino, Giuseppe

    2011-12-01

    We analyzed 12 MLL/ENL positive ALL patients consecutively diagnosed between 1999 and 2009. The MLL/ENL fusion was identified in 4/150 (2.6%), 8/993 (0.8%), and 0/70 of pediatric, adult, and elderly patients, respectively. Eight patients had a WBC count >50 × 10(9) /L. Ten cases had an evaluable immunophenotyping. A B or T precursor ALL occurred in 7 and 3 patients, respectively. Eleven/12 patients (92%) achieved CR. At 48 months, overall survival and event-free survival rates were 73.3% and 67%, respectively. At CR, a parallel RT-PCR evaluation of the MLL/ENL expression was available in 5 cases. Of these latter, 2 tested MLL/ENL-negative and 3 positive. The minimal residual disease molecular monitoring showed that MLL/ENL status did not correlate with outcome. In fact, all the 2 PCR-negative and 1 of the 3 PCR-positive cases relapsed. Further, a MLL/ENL expression, not preceding a relapse, was detected several times during the follow-up of five long-survivors. In conclusion, also in adults, the MLL/ENL fusion identifies a rare leukemic entity with a favorable prognosis. The observed inconsistency between the clinical cure and the presence of detectable MLL/ENL transcript suggests the existence of a MLL/ENL-expressing "preleukemia" stem cells, similar to what demonstrated for the AML1/ETO-positive leukemia setting. Copyright © 2011 Wiley-Liss, Inc.

  10. International reporting scale of BCR-ABL1 fusion transcript in chronic myeloid leukemia: first report from India.

    PubMed

    Balasubramanian, Poonkuzhali; Chendamarai, Ezhilarasi; Markose, Preetha; Fletcher, Linda; Branford, Susan; George, Biju; Mathews, Vikram; Chandy, Mammen; Srivastava, Alok

    2012-01-01

    Achieving a major molecular response (MMR) is an important predictor of progression-free survival in chronic myeloid leukemia patients treated with imatinib. This requires accurate measurement of BCR-ABL1 transcripts normalized to a control gene, as well as defining a level (BCR-ABL1/control gene ratio) that will correlate with sustained clinical response. To make these measurements comparable between laboratories, an international scale (IS) is necessary. A BCR-ABL1/control gene ratio of 0.10% represents MMR in the IS. In collaboration with an international reference laboratory in Adelaide, S.A., Australia, we have established and validated a lab-specific conversion factor for expressing BCR-ABL1 transcript levels in the IS. In this report, we explain the process and steps involved in obtaining a valid lab-specific conversion factor for expressing BCR-ABL1 transcript levels in the IS. Copyright © 2012 S. Karger AG, Basel.

  11. Identification of a Cryptic Insertion ins(11;X)(q23;q28q12) Resulting in a KMT2A-FLNA Fusion in a 13-Month-Old Child with Acute Myelomonocytic Leukemia.

    PubMed

    Lentes, Jana; Thomay, Kathrin; Schneider, Dominik T; Bernbeck, Benedikt; Reinhardt, Dirk; Marschalek, Rolf; Meyer, Claus; Schlegelberger, Brigitte; Göhring, Gudrun

    2016-01-01

    In pediatric acute myeloid leukemia (AML), chromosomal abnormalities leading to a disruption of the lysine methyltransferase 2A (KMT2A) gene in 11q23 are the most frequent rearrangements. Here, we report on the identification of a novel cryptic insertion, ins(11;X)(q23;q28q12), resulting in a translocation of the KMT2A gene in 11q23, leading to a KMT2A-FLNA fusion in a 13-month-old boy with de novo acute myelomonocytic leukemia, who died 38 days after diagnosis. The patient presented a complex karyotype 48∼49,Y,del(X)(q12),+del(X)(q12),+8,ins(11;X)(q23; q28q12),+19. The identified fusion gene was predicted to be out-of-frame (fusion of portions of KMT2A exon 11 with FLNA exon 11). However, RT-PCR experiments demonstrated that a potentially functional transcript was generated by alternative splicing where KMT2A exon 10 was spliced in-frame to the truncated FLNA exon 11. This case report helps to better understand the rare but potentially severe impact of KMT2A- FLNA fusions in infants with AML to improve prognostic stratification of therapy and clinical management.

  12. Quantification of minimal residual disease (MRD) in acute lymphoblastic leukemia (ALL) using amplicon-fusion-site polymerase chain reaction (AFS-PCR).

    PubMed

    Weber, Axel; Taube, Sylvia; Zur Stadt, Udo; Horstmann, Martin; Krohn, Knut; Bradtke, Jutta; Teigler-Schlegel, Andrea; Leiblein, Sabine; Christiansen, Holger

    2012-11-09

    The amplification of putative oncogenes is a common finding within the genome of various cancer types. Identification and further targeting of specific junction sites within the sequence of genomic amplicons (amplicon fusion sites, AFS) by PCR (AFS-PCR) is suitable for quantification of minimal residual disease (MRD). This approach has recently been developed and described for MYCN amplified neuroblastomas. To compare AFS-PCR directly to routinely used MRD diagnostic strategies, we mapped the amplified genomic regions (ampGR) of an iAMP21-amplicon in high resolution of a patient with acute lymphoblastic leukemia (ALL). Successfully, we established AFS-PCR covering junction sites between ampGR within the iAMP21-amplicon. Quantification of MRD by AFS-PCR was directly comparable to IgH/TCR based real time quantitative PCR and fluorescence activated cell sorting (FACS) analysis in consecutive bone marrow (BM) specimens. Our data give an additional proof of concept of AFS-PCR for quantification of MRD. The method could be taken into account for ALL patients with genomic amplifications as alternative MRD diagnostic, if no or qualitatively poor Ig/TCR-PCRs are available.

  13. TAF15 and the leukemia-associated fusion protein TAF15-CIZ/NMP4 are cleaved by caspases-3 and -7

    SciTech Connect

    Alves, Juliano; Wurdak, Heiko; Garay-Malpartida, Humberto M.; Harris, Jennifer L.; Occhiucci, Joao M.; Belizario, Jose E.; Li, Jun

    2009-07-10

    Caspases are central players in proteolytic pathways that regulate cellular processes such as apoptosis and differentiation. To accelerate the discovery of novel caspase substrates we developed a method combining in silico screening and in vitro validation. With this approach, we identified TAF15 as a novel caspase substrate in a trial study. We find that TAF15 was specifically cleaved by caspases-3 and -7. Site-directed mutagenesis revealed the consensus sequence {sup 106}DQPD/Y{sup 110} as the only site recognized by these caspases. Surprisingly, TAF15 was cleaved at more than one site in staurosporine-treated Jurkat cells. In addition, we generated two oncogenic TAF15-CIZ/NMP4-fused proteins which have been found in acute myeloid leukemia and demonstrate that caspases-3 and -7 cleave the fusion proteins at one single site. Broad application of this combination approach should expedite identification of novel caspase-interacting proteins and provide new insights into the regulation of caspase pathways leading to cell death in normal and cancer cells.

  14. Characterization of a fusion cDNA (RARA/myl) transcribed from the t(15;17) translocation breakpoint in acute promyelocytic leukemia.

    PubMed Central

    Chang, K S; Stass, S A; Chu, D T; Deaven, L L; Trujillo, J M; Freireich, E J

    1992-01-01

    A nonrandom chromosomal translocation breakpoint, t(15;17)(q22;q21), is found in almost all patients with acute promyelocytic leukemia (APL). Most of these breakpoints occur within the second intron of the retinoic acid receptor-alpha (RARA) gene. We screened a cDNA library of APL and have identified and sequenced a cDNA transcribed from the t(15;17) translocation breakpoint. The 5' end of cDNA p1715 consists of 503 bp of the RARA exon II sequence. A 1.76-kb cDNA without homology to any known gene available in GenBank was found truncated downstream. This cDNA sequence was assigned to chromosome 15 by dot blot hybridization of the flow cytometry-sorted chromosomes. We designate this fusion cDNA RARA/myl, which is different from myl/RARA reported by de The et al. (H. de The, C. Chomienne, M. Lanotte, L. Degos, and A. Dejean, Nature (London) 347:558-561, 1990). This result demonstrates that the two different types of hybrid mRNA can be transcribed from this breakpoint. We screened a non-APL cDNA library and identified a 2.8-kb myl cDNA. This cDNA is able to encode a polypeptide with a molecular weight of 78,450. Alternative splicing of the myl gene which resulted in myl proteins with different C terminals was found. Southern blot analysis of the genomic DNA isolated from 17 APL patients by using the myl DNA probe demonstrated that the myl gene in 12 samples was rearranged. Northern (RNA) blot analysis of RARA gene expression in two APL RNA samples showed abnormal mRNA species of 4.2 and 3.2 kb in one patient and of 4.8 and 3.8 kb in another patient; these were in addition to the normal mRNA species of 3.7 and 2.7-kb. The myl DNA probe detected a 2.6-kb abnormal mRNA in addition to the normal mRNA species of 3.2, 4.2, and 5.5 kb. Using the polymerase chain reaction, we demonstrated that both RARA/myl and myl/RARA were coexpressed in samples from three different APL patients. From this study, we conclude that the t(15;17) translocation breakpoint results in the

  15. Opposite effects of the acute promyelocytic leukemia PML-retinoic acid receptor alpha (RAR alpha) and PLZF-RAR alpha fusion proteins on retinoic acid signalling.

    PubMed Central

    Ruthardt, M; Testa, U; Nervi, C; Ferrucci, P F; Grignani, F; Puccetti, E; Grignani, F; Peschle, C; Pelicci, P G

    1997-01-01

    Fusion proteins involving the retinoic acid receptor alpha (RAR alpha) and the PML or PLZF nuclear protein are the genetic markers of acute promyelocytic leukemias (APLs). APLs with the PML-RAR alpha or the PLZF-RAR alpha fusion protein are phenotypically indistinguishable except that they differ in their sensitivity to retinoic acid (RA)-induced differentiation: PML-RAR alpha blasts are sensitive to RA and patients enter disease remission after RA treatment, while patients with PLZF-RAR alpha do not. We here report that (i) like PML-RAR alpha expression, PLZF-RAR alpha expression blocks terminal differentiation of hematopoietic precursor cell lines (U937 and HL-60) in response to different stimuli (vitamin D3, transforming growth factor beta1, and dimethyl sulfoxide); (ii) PML-RAR alpha, but not PLZF-RAR alpha, increases RA sensitivity of hematopoietic precursor cells and restores RA sensitivity of RA-resistant hematopoietic cells; (iii) PML-RAR alpha and PLZF-RAR alpha have similar RA binding affinities; and (iv) PML-RAR alpha enhances the RA response of RA target genes (those for RAR beta, RAR gamma, and transglutaminase type II [TGase]) in vivo, while PLZF-RAR alpha expression has either no effect (RAR beta) or an inhibitory activity (RAR gamma and type II TGase). These data demonstrate that PML-RAR alpha and PLZF-RAR alpha have similar (inhibitory) effects on RA-independent differentiation and opposite (stimulatory or inhibitory) effects on RA-dependent differentiation and that they behave in vivo as RA-dependent enhancers or inhibitors of RA-responsive genes, respectively. Their different activities on the RA signalling pathway might underlie the different responses of PML-RAR alpha and PLZF-RAR alpha APLs to RA treatment. The PLZF-RAR alpha fusion protein contains an approximately 120-amino-acid N-terminal motif (called the POZ domain), which is also found in a variety of zinc finger proteins and a group of poxvirus proteins and which mediates protein

  16. Leukemia - B-Cell Prolymphocytic Leukemia and Hairy Cell Leukemia

    MedlinePlus

    ... and Hairy Cell Leukemia: Introduction Request Permissions Leukemia - B-cell Prolymphocytic Leukemia and Hairy Cell Leukemia: Introduction ... t k e P Types of Cancer Leukemia - B-cell Prolymphocytic Leukemia and Hairy Cell Leukemia Guide ...

  17. Frequency of the ETV6-RUNX1, BCR-ABL1, TCF3-PBX1, and MLL-AFF1 fusion genes in Guatemalan pediatric acute lymphoblastic leukemia patients and their ethnic associations.

    PubMed

    Carranza, Claudia; Granados, Lilian; Morales, Oneida; Jo, Wendy; Villagran, Swuanny; Tinti, Damaris; Villegas, Mauricio; Antillón, Federico; Torselli, Silvana; Silva, Gabriel

    2013-06-01

    Fusion genes involved in acute lymphoblastic leukemia (ALL) occur mostly due to genetic and environmental factors, and only a limited number of studies have reported any ethnic influence. This study assesses whether an ethnic influence has an effect on the frequency of any of the four fusion genes: BCR-ABL1, ETV6-RUNX1, TCF3-PBX1, and MLL-AFF1 found in ALL. To study this ethnic influence, mononuclear cells were obtained from bone marrow samples from 143 patients with ALL. We performed RNA extraction and reverse transcription, then assessed the quality of the cDNA by amplifying the ABL1 control gene, and finally evaluated the presence of the four transcripts by multiplex polymerase chain reaction. We found 10 patients who had the BCR-ABL1 fusion gene (7%); 3 patients (2%) were TCF3-PBX1 positive; and 6 patients (4.5%) were ETV6-RUNX1 positive. The incidence of this last fusion gene is quite low when compared to the values reported in most countries. The low incidence of the ETV6-RUNX1 fusion gene found in Guatemala matches the incidence rates that have been reported in Spain and Indian Romani. Since it is known that an ethnic resemblance exists among these three populations, as shown by ancestral marker studies, the ALL data suggests an ethnic influence on the occurrence and frequency of this particular fusion gene. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. inv(16)/t(16;16) acute myeloid leukemia with non-type A CBFB-MYH11 fusions associate with distinct clinical and genetic features and lack KIT mutations.

    PubMed

    Schwind, Sebastian; Edwards, Colin G; Nicolet, Deedra; Mrózek, Krzysztof; Maharry, Kati; Wu, Yue-Zhong; Paschka, Peter; Eisfeld, Ann-Kathrin; Hoellerbauer, Pia; Becker, Heiko; Metzeler, Klaus H; Curfman, John; Kohlschmidt, Jessica; Prior, Thomas W; Kolitz, Jonathan E; Blum, William; Pettenati, Mark J; Dal Cin, Paola; Carroll, Andrew J; Caligiuri, Michael A; Larson, Richard A; Volinia, Stefano; Marcucci, Guido; Bloomfield, Clara D

    2013-01-10

    The inv(16)(p13q22)/t(16;16)(p13;q22) in acute myeloid leukemia results in multiple CBFB-MYH11 fusion transcripts, with type A being most frequent. The biologic and prognostic implications of different fusions are unclear. We analyzed CBFB-MYH11 fusion types in 208 inv(16)/t(16;16) patients with de novo disease, and compared clinical and cytogenetic features and the KIT mutation status between type A (n = 182; 87%) and non-type A (n = 26; 13%) patients. At diagnosis, non-type A patients had lower white blood counts (P = .007), and more often trisomies of chromosomes 8 (P = .01) and 21 (P < .001) and less often trisomy 22 (P = .02). No patient with non-type A fusion carried a KIT mutation, whereas 27% of type A patients did (P = .002). Among the latter, KIT mutations conferred adverse prognosis; clinical outcomes of non-type A and type A patients with wild-type KIT were similar. We also derived a fusion-type-associated global gene-expression profile. Gene Ontology analysis of the differentially expressed genes revealed-among others-an enrichment of up-regulated genes involved in activation of caspase activity, cell differentiation and cell cycle control in non-type A patients. We conclude that non-type A fusions associate with distinct clinical and genetic features, including lack of KIT mutations, and a unique gene-expression profile.

  19. Virus-induced congenital malformations in cattle.

    PubMed

    Agerholm, Jørgen S; Hewicker-Trautwein, Marion; Peperkamp, Klaas; Windsor, Peter A

    2015-09-24

    Diagnosing the cause of bovine congenital malformations (BCMs) is challenging for bovine veterinary practitioners and laboratory diagnosticians as many known as well as a large number of not-yet reported syndromes exist. Foetal infection with certain viruses, including bovine virus diarrhea virus (BVDV), Schmallenberg virus (SBV), blue tongue virus (BTV), Akabane virus (AKAV), or Aino virus (AV), is associated with a range of congenital malformations. It is tempting for veterinary practitioners to diagnose such infections based only on the morphology of the defective offspring. However, diagnosing a virus as a cause of BCMs usually requires laboratory examination and even in such cases, interpretation of findings may be challenging due to lack of experience regarding genetic defects causing similar lesions, even in cases where virus or congenital antibodies are present. Intrauterine infection of the foetus during the susceptible periods of development, i.e. around gestation days 60-180, by BVDV, SBV, BTV, AKAV and AV may cause malformations in the central nervous system, especially in the brain. Brain lesions typically consist of hydranencephaly, porencephaly, hydrocephalus and cerebellar hypoplasia, which in case of SBV, AKAV and AV infections may be associated by malformation of the axial and appendicular skeleton, e.g. arthrogryposis multiplex congenita. Doming of the calvarium is present in some, but not all, cases. None of these lesions are pathognomonic so diagnosing a viral cause based on gross lesions is uncertain. Several genetic defects share morphology with virus induced congenital malformations, so expert advice should be sought when BCMs are encountered.

  20. Structure, localization and transcriptional properties of two classes of retinoic acid receptor alpha fusion proteins in acute promyelocytic leukemia (APL): structural similarities with a new family of oncoproteins.

    PubMed Central

    Kastner, P; Perez, A; Lutz, Y; Rochette-Egly, C; Gaub, M P; Durand, B; Lanotte, M; Berger, R; Chambon, P

    1992-01-01

    Acute promyelocytic leukemia (APL) is due to a chromosomal t(15;17) translocation which involves a novel human gene, Myl, (also named PML) and the retinoic acid (RA) receptor alpha (RAR-alpha) gene. We report here the characterization of Myl and of the reciprocal MylRAR (PMLRAR) and RARMyl (RARPML) fusion transcripts which are found in two classes of APL patients. Myl displays similarities with a new family of proteins of which some members are fused to protooncogenes in the transforming proteins RFP-ret and T18. The speckled nuclear localization of Myl, as well as its sequence homology with the 52 kDa component of the RO/SSA ribonucleoprotein particle, suggest that Myl may be present in a ribonucleoprotein complex. In contrast to both Myl and RAR-alpha whose localization is essentially nuclear in the presence or absence of RA, MylRAR which is largely cytoplasmic in the absence of RA appears to be translocated to the nucleus in the presence of RA. Myl and MylRAR can associate in vitro and this association is mediated by a coiled coil in the Myl sequence. In vivo this association results in a colocalization of Myl and MylRAR which is identical to that of MylRAR alone. Studies of activation of transcription from the promoters of several RA target genes indicate that MylRARs have altered transcription activation properties when compared with RAR-alpha. Most notably, MylRAR represses markedly the activity of some RA target promoters in the absence of RA. Western blot analyses of patient samples show that MylRAR is expressed to a much higher level than wild type RAR-alpha originating from the normal allele. Taken together, these results suggest that MylRAR may interfere in a dominant manner with both Myl and RAR functions. Images PMID:1311253

  1. Minimal residual disease monitoring in childhood B lymphoblastic leukemia with t(12;21)(p13;q22); ETV6-RUNX1: concordant results using quantitation of fusion transcript and flow cytometry.

    PubMed

    Alm, S J; Engvall, C; Asp, J; Palmqvist, L; Abrahamsson, J; Fogelstrand, L

    2017-04-01

    The translocation t(12;21)(p13;q22) resulting in the fusion gene ETV6-RUNX1, is the most frequent gene fusion in childhood B lymphoblastic leukemia. In the Nordic Society of Paediatric Haematology and Oncology ALL-2008 treatment protocol, treatment stratification in B-lineage ALL is based on results of minimal residual disease (MRD) analysis with fluorescence-activated cell sorting (FACS). In this study, we determined whether RT-qPCR of the ETV6-RUNX1 fusion transcript can be a reliable alternative for MRD analysis. Seventy-eight bone marrow samples from 29 children at diagnosis and day 15, 29, and 78 during treatment were analyzed for MRD with FACS and with quantitative reverse transcription polymerase chain reaction (RT-qPCR). Fusion transcript MRD was defined as the ETV6-RUNX1/GUSB ratio at the follow-up time point (day 15/29/78) divided with the ETV6-RUNX1/GUSB ratio at diagnosis (%). MRD analysis with FACS and with RT-qPCR of ETV6-RUNX1 fusion transcript showed strong correlation. All cases showed concordant results at the treatment stratifying time points day 29 and day 78, when comparing the two methods with a cutoff set to 0.1%. RT-qPCR is a valuable addition and could also be an alternative to FACS in cases where FACS is not achievable for MRD analysis. © 2016 John Wiley & Sons Ltd.

  2. Leukemia - resources

    MedlinePlus

    The following organizations provide information on the different types of leukemia : Cancer Care -- www.cancercare.org/diagnosis/leukemia National Cancer Institute -- www.cancer.gov/types/leukemia The ...

  3. Activation of Membrane Fusion by Murine Leukemia Viruses Is Controlled in cis or in trans by Interactions between the Receptor-Binding Domain and a Conserved Disulfide Loop of the Carboxy Terminus of the Surface Glycoprotein

    PubMed Central

    Lavillette, Dimitri; Boson, Bertrand; Russell, Stephen J.; Cosset, François-Loïc

    2001-01-01

    Cell entry of retroviruses is initiated by the recognition of cellular receptors and the subsequent membrane fusion between viral and cellular membranes. These two steps are mediated by the surface (SU) and transmembrane (TM) subunits of the retroviral envelope glycoprotein (Env), respectively. Determinants regulating membrane fusion have been described throughout SU and TM, but the processes coupling receptor recognition to fusion are still elusive. Here we establish that a critical interaction is formed between the receptor-binding domain (RBD) and the major disulfide loop of the carboxy-terminal domain (C domain) of the murine leukemia virus SU. Receptor binding causes an alteration of this interaction and, in turn, promotes further events of Env fusion activation. We characterize mutations which, by lowering this interaction and reducing the compatibility between the RBD and C domains of Env glycoprotein chimeras, affect both Env fusogenicity and sensitivity to receptor interference. Additionally, we demonstrate that suboptimal interactions in such mutant Env proteins can be compensated in trans by soluble RBDs in a manner that depends on their compatibility with the C domain. Our results therefore indicate that RBD/C domain interactions may occur in cis, via the proper RBD of the viral Env itself, or in trans, via a distinct RBD expressed by virion-free Env glycoproteins expressed endogenously by the infected cells or provided by neighboring Env trimers. PMID:11264358

  4. RIG-I Signaling Is Essential for Influenza B Virus-Induced Rapid Interferon Gene Expression

    PubMed Central

    Österlund, Pamela; Westenius, Veera; Latvala, Sinikka; Diamond, Michael S.; Gale, Michael; Julkunen, Ilkka

    2015-01-01

    ABSTRACT Influenza B virus causes annual epidemics and, along with influenza A virus, accounts for substantial disease and economic burden throughout the world. Influenza B virus infects only humans and some marine mammals and is not responsible for pandemics, possibly due to a very low frequency of reassortment and a lower evolutionary rate than that of influenza A virus. Influenza B virus has been less studied than influenza A virus, and thus, a comparison of influenza A and B virus infection mechanisms may provide new insight into virus-host interactions. Here we analyzed the early events in influenza B virus infection and interferon (IFN) gene expression in human monocyte-derived macrophages and dendritic cells. We show that influenza B virus induces IFN regulatory factor 3 (IRF3) activation and IFN-λ1 gene expression with faster kinetics than does influenza A virus, without a requirement for viral protein synthesis or replication. Influenza B virus-induced activation of IRF3 required the fusion of viral and endosomal membranes, and nuclear accumulation of IRF3 and viral NP occurred concurrently. In comparison, immediate early IRF3 activation was not observed in influenza A virus-infected macrophages. Experiments with RIG-I-, MDA5-, and RIG-I/MDA5-deficient mouse fibroblasts showed that RIG-I is the critical pattern recognition receptor needed for the influenza B virus-induced activation of IRF3. Our results show that innate immune mechanisms are activated immediately after influenza B virus entry through the endocytic pathway, whereas influenza A virus avoids early IRF3 activation and IFN gene induction. IMPORTANCE Recently, a great deal of interest has been paid to identifying the ligands for RIG-I under conditions of natural infection, as many previous studies have been based on transfection of cells with different types of viral or synthetic RNA structures. We shed light on this question by analyzing the earliest step in innate immune recognition of

  5. Imatinib Mesylate and Combination Chemotherapy in Treating Patients With Newly Diagnosed Philadelphia Chromosome Positive Acute Lymphoblastic Leukemia

    ClinicalTrials.gov

    2017-09-06

    Acute Lymphoblastic Leukemia; B Acute Lymphoblastic Leukemia With t(9;22)(q34.1;q11.2); BCR-ABL1; BCR-ABL1 Fusion Protein Expression; Minimal Residual Disease; Philadelphia Chromosome Positive; T Acute Lymphoblastic Leukemia; Untreated Adult Acute Lymphoblastic Leukemia; Untreated Childhood Acute Lymphoblastic Leukemia

  6. 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.

  7. Mechanisms Involved in Virus-Induced Neural Cell Death

    DTIC Science & Technology

    2001-09-01

    We are using experimental infection with reoviruses as a model to study how viruses induce cell death (apoptosis) and cause dysregulation of the cell...and their ligand (TRAIL). Apoptosis involves both death-receptor (DR) and mitochondrial-associated cell death pathways, and leads to the early

  8. Virus-Induced gene silencing in ornamental plants

    USDA-ARS?s Scientific Manuscript database

    Virus-Induced Gene Silencing (VIGS) provides an attractive tool for high throughput analysis of the functional effects of gene knock-down. Virus genomes are engineered to include fragments of target host genes, and the infected plant recognizes and silences the target genes as part of its viral defe...

  9. Virus-Induced Gene Silencing in Ornametal Plants

    USDA-ARS?s Scientific Manuscript database

    Virus-Induced Gene Silencing (VIGS) provides an attractive tool for high throughput analysis of the functional effects of gene knock-down. Virus genomes are engineered to include fragments of target host genes, and the infected plant recognizes and silences the target genes as part of its viral defe...

  10. Virus-induced gene silencing (VIGS) in barley seedling leaves

    USDA-ARS?s Scientific Manuscript database

    Virus-induced gene silencing (VIGS) is one of the most potent reverse genetics technologies for gene functional characterization. This method exploits a dsRNA-mediated antiviral defense mechanism in plants. Using this method allows researchers to generate rapid phenotypic data in a relatively rapid ...

  11. DT388-GM-CSF, a novel fusion toxin consisting of a truncated diphtheria toxin fused to human granulocyte-macrophage colony-stimulating factor, prolongs host survival in a SCID mouse model of acute myeloid leukemia.

    PubMed

    Hall, P D; Willingham, M C; Kreitman, R J; Frankel, A E

    1999-04-01

    Despite significant advances in the treatment of acute myeloid leukemia (AML), the majority of patients will succumb to drug-resistant AML. To overcome this resistance, we have developed a novel fusion toxin consisting of the catalytic and translocation subunits of diphtheria toxin (DT388) linked to human granulocyte-macrophage colony-stimulating factor (GM-CSF). In vitro, DT388-GM-CSF demonstrated significant activity against numerous AML cell lines and fresh AML blasts. To determine its in vivo efficacy, we developed an in vivo model of human AML in severe combined immunodeficiency (SCID) mice injected intravenously with 1 x 10(7) HL-60 cells (AML-M2 cell line). The SCID mice developed abdominal masses, infiltration of the liver and bone marrow, and peripheral blasts with a median survival of 42.5 days. We tested DT388-GM-CSF, ara-C, human GM-CSF, and DAB389IL-2, which were injected intraperitoneally on days 2-6 in this model. DT3-GM-CSF significantly improved survival of the SCID mice over Ara-C, DAB389IL-2, or control (P < 0.001). DT388-GM-CSF-treated mice who developed leukemia exhibited no difference in the number of GM-CSF receptors (P = 0.39), ligand affinity (P = 0.77), or sensitivity (P = 0.56) to DT388-GM-CSF as compared to the controls. Frank leukemia in DT388-GM-CSF-treated mice may be due to incomplete penetration of drug into tissues rather than cellular resistance. DT388-GM-CSF is an active therapeutic agent in our SCID mouse model of AML with a unique mechanism of action and differing toxicities than current cytotoxic agents.

  12. BCR-ABL fusion transcript types and levels and their interaction with secondary genetic changes in determining the phenotype of Philadelphia chromosome–positive leukemias

    PubMed Central

    Luthra, Rajyalakshmi; Cortes, Jorge; Thomas, Deborah; O'Brien, Susan; Bueso-Ramos, Carlos; Hai, Seema; Ravandi, Farhad; de Lima, Marcos; Kantarjian, Hagop; Jorgensen, Jeffrey L.

    2008-01-01

    It remains unresolved how different BCR-ABL transcripts differentially drive lymphoid and myeloid proliferation in Philadelphia chromosome–positive (Ph+) leukemias. We compared BCR-ABL transcript type and level with kinase domain (KD) mutation status, genotype, and phenotype in 1855 Ph+ leukemias. Compared with e1a2/p190 BCR-ABL cases, de novo e13-e14a2/p210 Ph+ lymphoid leukemia more frequently showed CML-type background, had higher blast-normalized BCR-ABL transcript levels, and more frequent persistent BCR-ABL transcript in the absence of detectable lymphoblasts. Secondary lymphoid blast transformation of CML was exclusively due to e13/e14a2/p210 BCR-ABL but was associated, at a much higher level than p210 myeloid transformation, with acquisition of new KD mutations and/or Ph genomic amplification. In contrast, myeloid blast transformation was more frequently accompanied by new acquisition of acute myeloid leukemia-type chromosomal aberrations, particularly involving the EVI1 and RUNX1 loci. Therefore, higher kinase activity by mutation, transcriptional up-regulation or gene amplification appears required for lymphoid transformation by p210 BCR-ABL. PMID:18809762

  13. Chronic myelogenous leukemia (CML)

    MedlinePlus

    CML; Chronic myeloid leukemia; Chronic granulocytic leukemia; Leukemia - chronic granulocytic ... nuclear disaster. It takes many years to develop leukemia from radiation exposure. Most people treated for cancer ...

  14. Childhood Leukemia

    MedlinePlus

    Leukemia is cancer of the white blood cells. It is the most common type of childhood cancer. ... blood cells help your body fight infection. In leukemia, the bone marrow produces abnormal white blood cells. ...

  15. Mechanisms of Virus-Induced Neural Cell Death

    DTIC Science & Technology

    2003-09-01

    We are using experimental infection with reoviruses to study how viruses induce cell death . (apoptosis), and the significance of apoptosis in the...pathogenesis of viral infection. We have developed one of the best-characterized experimental models for investigating and manipulating viral cell death pathways...We have shown that apoptosis is a major mechanism of reovirus-induced cell death in murine models of key human viral infections including

  16. Influenza virus induces apoptosis via BAD-mediated mitochondrial dysregulation.

    PubMed

    Tran, Anh T; Cortens, John P; Du, Qiujiang; Wilkins, John A; Coombs, Kevin M

    2013-01-01

    Influenza virus infection results in host cell death and major tissue damage. Specific components of the apoptotic pathway, a signaling cascade that ultimately leads to cell death, are implicated in promoting influenza virus replication. BAD is a cell death regulator that constitutes a critical control point in the intrinsic apoptosis pathway, which occurs through the dysregulation of mitochondrial outer membrane permeabilization and the subsequent activation of downstream apoptogenic factors. Here we report a novel proviral role for the proapoptotic protein BAD in influenza virus replication. We show that influenza virus-induced cytopathology and cell death are considerably inhibited in BAD knockdown cells and that both virus replication and viral protein production are dramatically reduced, which suggests that virus-induced apoptosis is BAD dependent. Our data showed that influenza viruses induced phosphorylation of BAD at residues S112 and S136 in a temporal manner. Viral infection also induced BAD cleavage, late in the viral life cycle, to a truncated form that is reportedly a more potent inducer of apoptosis. We further demonstrate that knockdown of BAD resulted in reduced cytochrome c release and suppression of the intrinsic apoptotic pathway during influenza virus replication, as seen by an inhibition of caspases-3, caspase-7, and procyclic acidic repetitive protein (PARP) cleavage. Our data indicate that influenza viruses carefully modulate the activation of the apoptotic pathway that is dependent on the regulatory function of BAD and that failure of apoptosis activation resulted in unproductive viral replication.

  17. Influenza Virus Induces Apoptosis via BAD-Mediated Mitochondrial Dysregulation

    PubMed Central

    Tran, Anh T.; Cortens, John P.; Du, Qiujiang; Wilkins, John A.

    2013-01-01

    Influenza virus infection results in host cell death and major tissue damage. Specific components of the apoptotic pathway, a signaling cascade that ultimately leads to cell death, are implicated in promoting influenza virus replication. BAD is a cell death regulator that constitutes a critical control point in the intrinsic apoptosis pathway, which occurs through the dysregulation of mitochondrial outer membrane permeabilization and the subsequent activation of downstream apoptogenic factors. Here we report a novel proviral role for the proapoptotic protein BAD in influenza virus replication. We show that influenza virus-induced cytopathology and cell death are considerably inhibited in BAD knockdown cells and that both virus replication and viral protein production are dramatically reduced, which suggests that virus-induced apoptosis is BAD dependent. Our data showed that influenza viruses induced phosphorylation of BAD at residues S112 and S136 in a temporal manner. Viral infection also induced BAD cleavage, late in the viral life cycle, to a truncated form that is reportedly a more potent inducer of apoptosis. We further demonstrate that knockdown of BAD resulted in reduced cytochrome c release and suppression of the intrinsic apoptotic pathway during influenza virus replication, as seen by an inhibition of caspases-3, caspase-7, and procyclic acidic repetitive protein (PARP) cleavage. Our data indicate that influenza viruses carefully modulate the activation of the apoptotic pathway that is dependent on the regulatory function of BAD and that failure of apoptosis activation resulted in unproductive viral replication. PMID:23135712

  18. Epidemiology of virus-induced asthma exacerbations: with special reference to the role of human rhinovirus

    PubMed Central

    Saraya, Takeshi; Kurai, Daisuke; Ishii, Haruyuki; Ito, Anri; Sasaki, Yoshiko; Niwa, Shoichi; Kiyota, Naoko; Tsukagoshi, Hiroyuki; Kozawa, Kunihisa; Goto, Hajime; Takizawa, Hajime

    2014-01-01

    Viral respiratory infections may be associated with the virus-induced asthma in adults as well as children. Particularly, human rhinovirus is strongly suggested a major candidate for the associations of the virus-induced asthma. Thus, in this review, we reviewed and focused on the epidemiology, pathophysiology, and treatment of virus-induced asthma with special reference on human rhinovirus. Furthermore, we added our preliminary data regarding the clinical and virological findings in the present review. PMID:24904541

  19. The human formin-binding protein 17 (FBP17) interacts with sorting nexin, SNX2, and is an MLL-fusion partner in acute myelogeneous leukemia

    PubMed Central

    Fuchs, Uta; Rehkamp, Gönna; Haas, Oskar A.; Slany, Robert; König, Margit; Bojesen, Stig; Bohle, Rainer M.; Damm-Welk, Christine; Ludwig, Wolf-Dieter; Harbott, Jochen; Borkhardt, Arndt

    2001-01-01

    We have cloned a fusion partner of the MLL gene at 11q23 and identified it as the gene encoding the human formin-binding protein 17, FBP17. It maps to chromosome 9q34 centromeric to ABL. The gene fusion results from a complex chromosome rearrangement that was resolved by fluorescence in situ hybridization with various probes on chromosomes 9 and 11 as an ins(11;9)(q23;q34)inv(11)(q13q23). The rearrangement resulted in a 5′-MLL/FBP17-3′ fusion mRNA. We retrovirally transduced murine-myeloid progenitor cells with MLL/FBP17 to test its transforming ability. In contrast to MLL/ENL, MLL/ELL and other MLL-fusion genes, MLL/FBP17 did not give a positive readout in a serial replating assay. Therefore, we assume that additional cooperating genetic abnormalities might be needed to establish a full malignant phenotype. FBP17 consists of a C-terminal Src homology 3 domain and an N-terminal region that is homologous to the cell division cycle protein, cdc15, a regulator of the actin cytoskeleton in Schizosaccharomyces pombe. Both domains are separated by a consensus Rho-binding motif that has been identified in different Rho-interaction partners such as Rhotekin and Rhophilin. We evaluated whether FBP17 and members of the Rho family interact in vivo with a yeast two-hybrid assay. None of the various Rho proteins tested, however, interacted with FBP17. We screened a human kidney library and identified a sorting nexin, SNX2, as a protein interaction partner of FBP17. These data provide a link between the epidermal growth factor receptor pathway and an MLL fusion protein. PMID:11438682

  20. An Ultrasensitive Mechanism Regulates Influenza Virus-Induced Inflammation.

    PubMed

    Shoemaker, Jason E; Fukuyama, Satoshi; Eisfeld, Amie J; Zhao, Dongming; Kawakami, Eiryo; Sakabe, Saori; Maemura, Tadashi; Gorai, Takeo; Katsura, Hiroaki; Muramoto, Yukiko; Watanabe, Shinji; Watanabe, Tokiko; Fuji, Ken; Matsuoka, Yukiko; Kitano, Hiroaki; Kawaoka, Yoshihiro

    2015-06-01

    Influenza viruses present major challenges to public health, evident by the 2009 influenza pandemic. Highly pathogenic influenza virus infections generally coincide with early, high levels of inflammatory cytokines that some studies have suggested may be regulated in a strain-dependent manner. However, a comprehensive characterization of the complex dynamics of the inflammatory response induced by virulent influenza strains is lacking. Here, we applied gene co-expression and nonlinear regression analysis to time-course, microarray data developed from influenza-infected mouse lung to create mathematical models of the host inflammatory response. We found that the dynamics of inflammation-associated gene expression are regulated by an ultrasensitive-like mechanism in which low levels of virus induce minimal gene expression but expression is strongly induced once a threshold virus titer is exceeded. Cytokine assays confirmed that the production of several key inflammatory cytokines, such as interleukin 6 and monocyte chemotactic protein 1, exhibit ultrasensitive behavior. A systematic exploration of the pathways regulating the inflammatory-associated gene response suggests that the molecular origins of this ultrasensitive response mechanism lie within the branch of the Toll-like receptor pathway that regulates STAT1 phosphorylation. This study provides the first evidence of an ultrasensitive mechanism regulating influenza virus-induced inflammation in whole lungs and provides insight into how different virus strains can induce distinct temporal inflammation response profiles. The approach developed here should facilitate the construction of gene regulatory models of other infectious diseases.

  1. Defining leukemia stem cells in MLL-translocated leukemias: implications for novel therapeutic strategies.

    PubMed

    Faber, J; Armstrong, S A

    2007-01-01

    Hematological malignancies and probably many other tumors are dependent on highly proliferating and self-renewing cancer stem cells. An important question in the development of novel, less toxic antileukemic strategies specifically targeting leukemia stem cells is how closely leukemia stem cells are related to normal hematopoietic stem cells. It has been recently demonstrated that leukemia stem cells can be derived from different stages in normal hematopoiesis and have unique phenotypic and genetic features. Introduction of Mixed-lineage leukemia ( MLL)-fusion oncoproteins, frequently found in infant leukemias and therapy-related leukemias, into differentiated hematopoietic progenitor cells results in the generation of leukemias with a high frequency of leukemia stem cells. The progenitor-derived leukemia stem cells ectopically express a limited stem cell program while maintaining the global identity of differentiated myeloid cells. Development of therapeutic strategies that specifically target the leukemia stem cell program while sparing normal hematopoietic stem cells may represent a novel therapeutic approach in human leukemias with high efficacy yet less side effects.

  2. The target cell of transformation is distinct from the leukemia stem cell in murine CALM/AF10 leukemia models.

    PubMed

    Dutta, S; Krause, A; Vosberg, S; Herold, T; Ksienzyk, B; Quintanilla-Martinez, L; Tizazu, B; Chopra, M; Graf, A; Krebs, S; Blum, H; Greif, P A; Vetter, A; Metzeler, K; Rothenberg-Thurley, M; Schneider, M R; Dahlhoff, M; Spiekermann, K; Zimber-Strobl, U; Wolf, E; Bohlander, S K

    2016-05-01

    The CALM/AF10 fusion gene is found in various hematological malignancies including acute myeloid leukemia (AML), T-cell acute lymphoblastic leukemia and malignant lymphoma. We have previously identified the leukemia stem cell (LSC) in a CALM/AF10-driven murine bone marrow transplant AML model as B220+ lymphoid cells with B-cell characteristics. To identify the target cell for leukemic transformation or 'cell of origin of leukemia' (COL) in non-disturbed steady-state hematopoiesis, we inserted the CALM/AF10 fusion gene preceded by a loxP-flanked transcriptional stop cassette into the Rosa26 locus. Vav-Cre-induced panhematopoietic expression of the CALM/AF10 fusion gene led to acute leukemia with a median latency of 12 months. Mice expressing CALM/AF10 in the B-lymphoid compartment using Mb1-Cre or CD19-Cre inducer lines did not develop leukemia. Leukemias had a predominantly myeloid phenotype but showed coexpression of the B-cell marker B220, and had clonal B-cell receptor rearrangements. Using whole-exome sequencing, we identified an average of two to three additional mutations per leukemia, including activating mutations in known oncogenes such as FLT3 and PTPN11. Our results show that the COL for CALM/AF10 leukemia is a stem or early progenitor cell and not a cell of B-cell lineage with a phenotype similar to that of the LSC in CALM/AF10+ leukemia.

  3. Incidence and clinical relevance of TEL/AML1 fusion genes in children with acute lymphoblastic leukemia enrolled in the German and Italian multicenter therapy trials. Associazione Italiana Ematologia Oncologia Pediatrica and the Berlin-Frankfurt-Münster Study Group.

    PubMed

    Borkhardt, A; Cazzaniga, G; Viehmann, S; Valsecchi, M G; Ludwig, W D; Burci, L; Mangioni, S; Schrappe, M; Riehm, H; Lampert, F; Basso, G; Masera, G; Harbott, J; Biondi, A

    1997-07-15

    The molecular approach for the analysis of leukemia associated chromosomal translocations has led to the identification of prognostic relevant subgroups. In pediatric acute lymphoblastic leukemia (ALL), the most common translocations, t(9;22) and t(4;11), have been associated with a poorer clinical outcome. Recently the TEL gene at chromosome 12p13 and the AML1 gene at chromosome 21q22 were found to be involved in the translocation t(12;21)(p13;q22). By conventional cytogenetics, however, this chromosomal abnormality is barely detectable and occurs in less than 0.05% of childhood ALL. To investigate the frequency of the molecular equivalent of the t(12;21), the TEL/AML1 gene fusion, we have undertaken a prospective screening in the running German Berlin-Frankfurt-Münster (BFM) and Italian Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP) multicenter ALL therapy trials. We have analyzed 334 unselected cases of pediatric ALL patients consecutively referred over a period of 5 and 9 months, respectively. The overall incidence of the t(12;21) in pediatric ALL is 18.9%. The 63 cases positive for the TEL/AML1 chimeric products ranged in age between 1 and 12 years, and all but one showed CD10 and pre-B immunophenotype. Interestingly, one case displayed a pre-pre-B immunophenotype. Among the B-lineage subgroup, the t(12;21) occurs in 22.0% of the cases. Fifteen of 61 (24.6%) cases coexpressed at least two myeloid antigens (CD13, CD33, or CDw65) in more than 20% of the gated blast cells. DNA index was available for 59 of the 63 TEL/AML1 positive cases; a hyperdiploid DNA content (> or = 1.16) was detected in only four patients, being nonhyperdiploid in the remaining 55. Based on this prospective analysis, we retrospectively evaluated the impact of TEL/AML1 in prognosis by identifying the subset of B-lineage ALL children enrolled in the closed German ALL-BFM-90 and Italian ALL-AIEOP-91 protocols who had sufficient material for analysis. A total of 342 children

  4. Virus -induced plankton dynamic and sea spray oragnics

    NASA Astrophysics Data System (ADS)

    Facchini, Maria Cristina; O'Dowd, Colin; Danovaro, Roberto

    2015-04-01

    The processes that link phytoplankton biomass and productivity to the organic matter enrichment in sea spray aerosol are far from being understood and modelling predictions remain highly uncertain at the moment. While some studies have asserted that the enrichment of OM in sea spray aerosol is independent on marine productivity, others, on the contrary, have shown significant correlation with phytoplankton biomass and productivity (Chl-a retrieved by satellites). Here we show that viral infection of prokaryotes and phytoplankton, by inducing the release of large quantities of surfaceactive organic matter (cell debris, exudates and other colloidal gel-forming material), in part due to cell lysis and plankton defence reactions, and in part from rapid virus multiplication, triggers the organic matter (OM) enrichment in the sea-spray particles during blooms. We show that virus-induced bloom dynamics may explain the contrasting results present in literature on the link between primary productivity and OM sea spray enrichment.

  5. Cell entry of Lassa virus induces tyrosine phosphorylation of dystroglycan.

    PubMed

    Moraz, Marie-Laurence; Pythoud, Christelle; Turk, Rolf; Rothenberger, Sylvia; Pasquato, Antonella; Campbell, Kevin P; Kunz, Stefan

    2013-05-01

    The extracellular matrix (ECM) receptor dystroglycan (DG) serves as a cellular receptor for the highly pathogenic arenavirus Lassa virus (LASV) that causes a haemorrhagic fever with high mortality in human. In the host cell, DG provides a molecular link between the ECM and the actin cytoskeleton via the adapter proteins utrophin or dystrophin. Here we investigated post-translational modifications of DG in the context of LASV cell entry. Using the tyrosine kinase inhibitor genistein, we found that tyrosine kinases are required for efficient internalization of virus particles, but not virus-receptor binding. Engagement of cellular DG by LASV envelope glycoprotein (LASV GP) in human epithelial cells induced tyrosine phosphorylation of the cytoplasmic domain of DG. LASV GP binding to DG further resulted in dissociation of the adapter protein utrophin from virus-bound DG. This virus-induced dissociation of utrophin was affected by genistein treatment, suggesting a role of receptor tyrosine phosphorylation in the process.

  6. Cell entry of Lassa virus induces tyrosine phosphorylation of dystroglycan

    PubMed Central

    Moraz, Marie-Laurence; Pythoud, Christelle; Turk, Rolf; Rothenberger, Sylvia; Pasquato, Antonella; Campbell, Kevin P.; Kunz, Stefan

    2013-01-01

    The extracellular matrix (ECM) receptor dystroglycan (DG) serves as a cellular receptor for the highly pathogenic arenavirus Lassa virus (LASV) that causes a hemorrhagic fever with high mortality in man. In the host cell, DG provides a molecular link between the ECM and the actin cytoskeleton via the adapter proteins utrophin or dystrophin. Here we investigated post-translational modifications of DG in the context of LASV cell entry. Using the tyrosine kinase inhibitor genistein, we found that tyrosine kinases are required for efficient internalization of virus particles, but not virus-receptor binding. Engagement of cellular DG by LASV envelope glycoprotein (LASV GP) in human epithelial cells induced tyrosine phosphorylation of the cytoplasmic domain of DG. LASV GP binding to DG further resulted in dissociation of the adapter protein utrophin from virus-bound DG. This virus-induced dissociation of utrophin was affected by genistein treatment, suggesting a role of receptor tyrosine phosphorylation in the process. PMID:23279385

  7. Poxvirus entry and membrane fusion

    SciTech Connect

    Moss, Bernard . E-mail: bmoss@nih.gov

    2006-01-05

    The study of poxvirus entry and membrane fusion has been invigorated by new biochemical and microscopic findings that lead to the following conclusions: (1) the surface of the mature virion (MV), whether isolated from an infected cell or by disruption of the membrane wrapper of an extracellular virion, is comprised of a single lipid membrane embedded with non-glycosylated viral proteins; (2) the MV membrane fuses with the cell membrane, allowing the core to enter the cytoplasm and initiate gene expression; (3) fusion is mediated by a newly recognized group of viral protein components of the MV membrane, which are conserved in all members of the poxvirus family; (4) the latter MV entry/fusion proteins are required for cell to cell spread necessitating the disruption of the membrane wrapper of extracellular virions prior to fusion; and furthermore (5) the same group of MV entry/fusion proteins are required for virus-induced cell-cell fusion. Future research priorities include delineation of the roles of individual entry/fusion proteins and identification of cell receptors.

  8. The MN1-TEL fusion protein, encoded by the translocation (12;22)(p13;q11) in myeloid leukemia, is a transcription factor with transforming activity.

    PubMed

    Buijs, A; van Rompaey, L; Molijn, A C; Davis, J N; Vertegaal, A C; Potter, M D; Adams, C; van Baal, S; Zwarthoff, E C; Roussel, M F; Grosveld, G C

    2000-12-01

    The Tel gene (or ETV6) is the target of the translocation (12;22)(p13;q11) in myeloid leukemia. TEL is a member of the ETS family of transcription factors and contains the pointed protein interaction (PNT) domain and an ETS DNA binding domain (DBD). By contrast to other chimeric proteins that contain TEL's PNT domain, such as TEL-platelet-derived growth factor beta receptor in t(5;12)(q33;p13), MN1-TEL contains the DBD of TEL. The N-terminal MN1 moiety is rich in proline residues and contains two polyglutamine stretches, suggesting that MN1-TEL may act as a deregulated transcription factor. We now show that MN1-TEL type I, unlike TEL and MN1, transforms NIH 3T3 cells. The transforming potential depends on both N-terminal MN1 sequences and a functional TEL DBD. Furthermore, we demonstrate that MN1 has transcription activity and that MN1-TEL acts as a chimeric transcription factor on the Moloney sarcoma virus long terminal repeat and a synthetic promoter containing TEL binding sites. The transactivating capacity of MN1-TEL depended on both the DBD of TEL and sequences in MN1. MN1-TEL contributes to leukemogenesis by a mechanism distinct from that of other chimeric proteins containing TEL.

  9. Murine leukemia virus pol gene products: analysis with antisera generated against reverse transcriptase and endonuclease fusion proteins expressed in Escherichia coli

    SciTech Connect

    Hu, S.C.; Court, D.L.; Zweig, M.; Levin, J.G.

    1986-10-01

    The organization of the murine leukemia virus (MuLV) pol gene was investigated by expressing molecular clones containing AKR MuLV reverse transcriptase or endonuclease or both gene segments in Escherichia coli and generating specific antisera against the expressed bacterial proteins. Reaction of these antisera with detergent-disrupted virus precipitated and 80-kilodalton (kDa) protein, the MuLV reverse transcriptase, and a 46-kDa protein which we believe is the viral endonuclease. A third (50-kDa) protein, related to reverse transcriptase, was also precipitated. Bacterial extracts of clones expressing reverse transcriptase and endonuclease sequences competed with the viral 80- and 46-kDa proteins, respectively. These results demonstrate that the antisera are specific for viral reverse transcriptase and endonuclease. Immunoprecipitation of AKR MuLV with antisera prepared against a bacterial protein containing only endonuclease sequences led to the observation that reverse transcriptase and endonuclease can be associated as a complex involving a disulfide bond(s).

  10. Henipavirus membrane fusion and viral entry.

    PubMed

    Aguilar, Hector C; Iorio, Ronald M

    2012-01-01

    Nipah (NiV) and Hendra (HeV) viruses cause cell-cell fusion (syncytia) in brain, lung, heart, and kidney tissues, leading to encephalitis, pneumonia, and often death. Membrane fusion is essential to both viral entry and virus-induced cell-cell fusion, a hallmark of henipavirus infections. Elucidiation of the mechanism(s) of membrane fusion is critical to understanding henipavirus pathobiology and has the potential to identify novel strategies for the development of antiviral therapeutic agents. Henipavirus membrane fusion requires the coordinated actions of the viral attachment (G) and fusion (F) glycoproteins. Current henipavirus fusion models posit that attachment of NiV or HeV G to its cell surface receptors releases F from its metastable pre-fusion conformation to mediate membrane fusion. The identification of ephrinB2 and ephrinB3 as henipavirus receptors has paved the way for recent advances in our understanding of henipavirus membrane fusion. These advances highlight mechanistic similarities and differences between membrane fusion for the henipavirus and other genera within the Paramyxoviridae family. Here, we review these mechanisms and the current gaps in our knowledge in the field.

  11. Multimeric complexes of the PML-retinoic acid receptor alpha fusion protein in acute promyelocytic leukemia cells and interference with retinoid and peroxisome-proliferator signaling pathways.

    PubMed Central

    Jansen, J H; Mahfoudi, A; Rambaud, S; Lavau, C; Wahli, W; Dejean, A

    1995-01-01

    The t(15;17) chromosomal translocation, specific for acute promyelocytic leukemia (APL), fuses the PML gene to the retinoic acid receptor alpha (RAR alpha) gene, resulting in expression of a PML-RAR alpha hybrid protein. In this report, we analyzed the nature of PML-RAR alpha-containing complexes in nuclear protein extracts of t(15;17)-positive cells. We show that endogenous PML-RAR alpha can bind to DNA as a homodimer, in contrast to RAR alpha that requires the retinoid X receptor (RXR) dimerization partner. In addition, these cells contain oligomeric complexes of PML-RAR alpha and endogenous RXR. Treatment with retinoic acid results in a decrease of PML-RAR alpha protein levels and, as a consequence, of DNA binding by the different complexes. Using responsive elements from various hormone signaling pathways, we show that PML-RAR alpha homodimers have altered DNA-binding characteristics when compared to RAR alpha-RXR alpha heterodimers. In transfected Drosophila SL-3 cells that are devoid of endogenous retinoid receptors PML-RAR alpha inhibits transactivation by RAR alpha-RXR alpha heterodimers in a dominant fashion. In addition, we show that both normal retinoid receptors and the PML-RAR alpha hybrid bind and activate the peroxisome proliferator-activated receptor responsive element from the Acyl-CoA oxidase gene, indicating that retinoids and peroxisome proliferator receptors may share common target genes. These properties of PML-RAR alpha may contribute to the transformed phenotype of APL cells. Images Fig. 1 Fig. 2 Fig. 3 PMID:7638205

  12. Efficient Virus-Induced Gene Silencing in Solanum rostratum

    PubMed Central

    Meng, Lan-Huan; Wang, Rui-Heng; Zhu, Ben-Zhong; Zhu, Hong-Liang; Luo, Yun-Bo; Fu, Da-Qi

    2016-01-01

    Solanum rostratum is a “super weed” that grows fast, is widespread, and produces the toxin solanine, which is harmful to both humans and other animals. To our knowledge, no study has focused on its molecular biology owing to the lack of available transgenic methods and sequence information for S. rostratum. Virus-induced gene silencing (VIGS) is a powerful tool for the study of gene function in plants; therefore, in the present study, we aimed to establish tobacco rattle virus (TRV)-derived VIGS in S. rostratum. The genes for phytoene desaturase (PDS) and Chlorophyll H subunit (ChlH) of magnesium protoporphyrin chelatase were cloned from S. rostratum and used as reporters of gene silencing. It was shown that high-efficiency VIGS can be achieved in the leaves, flowers, and fruit of S. rostratum. Moreover, based on our comparison of three different types of infection methods, true leaf infection was found to be more efficient than cotyledon and sprout infiltration in long-term VIGS in multiple plant organs. In conclusion, the VIGS technology and tomato genomic sequences can be used in the future to study gene function in S. rostratum. PMID:27258320

  13. Virus-Induced Dormancy in the Archaeon Sulfolobus islandicus

    PubMed Central

    Bautista, Maria A.; Zhang, Changyi

    2015-01-01

    ABSTRACT We investigated the interaction between Sulfolobus spindle-shaped virus (SSV9) and its native archaeal host Sulfolobus islandicus. We show that upon exposure to SSV9, S. islandicus strain RJW002 has a significant growth delay where the majority of cells are dormant (viable but not growing) for 24 to 48 hours postinfection (hpi) compared to the growth of controls without virus. We demonstrate that in this system, dormancy (i) is induced by both active and inactive virus particles at a low multiplicity of infection (MOI), (ii) is reversible in strains with active CRISPR-Cas immunity that prevents the establishment of productive infections, and (iii) results in dramatic and rapid host death if virus persists in the culture even at low levels. Our results add a new dimension to evolutionary models of virus-host interactions, showing that the mere presence of a virus induces host cell stasis and death independent of infection. This novel, highly sensitive, and risky bet-hedging antiviral response must be integrated into models of virus-host interactions in this system so that the true ecological impact of viruses can be predicted and understood. PMID:25827422

  14. Virus-induced gene silencing in eggplant (Solanum melongena).

    PubMed

    Liu, Haiping; Fu, Daqi; Zhu, Benzhong; Yan, Huaxue; Shen, Xiaoying; Zuo, Jinhua; Zhu, Yi; Luo, Yunbo

    2012-06-01

    Eggplant (Solanum melongena) is an economically important vegetable requiring investigation into its various genomic functions. The current limitation in the investigation of genomic function in eggplant is the lack of effective tools available for conducting functional assays. Virus-induced gene silencing (VIGS) has played a critical role in the functional genetic analyses. In this paper, TRV-mediated VIGS was successfully elicited in eggplant. We first cloned the CDS sequence of PDS (PHYTOENE DESATURASE) in eggplant and then silenced the PDS gene. Photo-bleaching was shown on the newly-developed leaves four weeks after agroinoculation, indicating that VIGS can be used to silence genes in eggplant. To further illustrate the reliability of VIGS in eggplant, we selected Chl H, Su and CLA1 as reporters to elicit VIGS using the high-pressure spray method. Suppression of Chl H and Su led to yellow leaves, while the depletion of CLA1 resulted in albino. In conclusion, four genes, PDS, Chl H, Su (Sulfur), CLA1, were down-regulated significantly by VIGS, indicating that the VIGS system can be successfully applied in eggplant and is a reliable tool for the study of gene function. © 2012 Institute of Botany, Chinese Academy of Sciences.

  15. Zika Virus-Induced Microcephaly and Its Possible Molecular Mechanism.

    PubMed

    Faizan, Md Imam; Abdullah, Mohd; Ali, Sher; Naqvi, Irshad H; Ahmed, Anwar; Parveen, Shama

    2016-01-01

    Zika virus is an arthropod-borne re-emerging pathogen associated with the global pandemic of 2015-2016. The devastating effect of Zika viral infection is reflected by its neurological manifestations such as microcephaly in newborns. This scenario evoked our interest to uncover the neurotropic localization, multiplication of the virus, and the mechanism of microcephaly. The present report provides an overview of a possible molecular mechanism of Zika virus-induced microcephaly based on recent publications. Transplacental transmission of Zika viral infection from mother to foetus during the first trimester of pregnancy results in propagation of the virus in human neural progenitor cells (hNPCs), where entry is facilitated by the receptor (AXL protein) leading to the alteration of signalling and immune pathways in host cells. Further modification of the viral-induced TLR3-mediated immune network in the infected hNPCs affects viral replication. Downregulation of neurogenesis and upregulation of apoptosis in hNPCs leads to cell cycle arrest and death of the developing neurons. In addition, it is likely that the environmental, physiological, immunological, and genetic factors that determine in utero transmission of Zika virus are also involved in neurotropism. Despite the global concern regarding the Zika-mediated epidemic, the precise molecular mechanism of neuropathogenesis remains elusive.

  16. Virus-induced exacerbations in asthma and COPD

    PubMed Central

    Kurai, Daisuke; Saraya, Takeshi; Ishii, Haruyuki; Takizawa, Hajime

    2013-01-01

    Chronic obstructive pulmonary disease (COPD) is characterized by chronic airway inflammation and/or airflow limitation due to pulmonary emphysema. Chronic bronchitis, pulmonary emphysema, and bronchial asthma may all be associated with airflow limitation; therefore, exacerbation of asthma may be associated with the pathophysiology of COPD. Furthermore, recent studies have suggested that the exacerbation of asthma, namely virus-induced asthma, may be associated with a wide variety of respiratory viruses. COPD and asthma have different underlying pathophysiological processes and thus require individual therapies. Exacerbation of both COPD and asthma, which are basically defined and diagnosed by clinical symptoms, is associated with a rapid decline in lung function and increased mortality. Similar pathogens, including human rhinovirus, respiratory syncytial virus, influenza virus, parainfluenza virus, and coronavirus, are also frequently detected during exacerbation of asthma and/or COPD. Immune response to respiratory viral infections, which may be related to the severity of exacerbation in each disease, varies in patients with both COPD and asthma. In this regard, it is crucial to recognize and understand both the similarities and differences of clinical features in patients with COPD and/or asthma associated with respiratory viral infections, especially in the exacerbative stage. In relation to definition, epidemiology, and pathophysiology, this review aims to summarize current knowledge concerning exacerbation of both COPD and asthma by focusing on the clinical significance of associated respiratory virus infections. PMID:24098299

  17. Virus-induced gene silencing in Rauwolfia species.

    PubMed

    Corbin, Cyrielle; Lafontaine, Florent; Sepúlveda, Liuda Johana; Carqueijeiro, Ines; Courtois, Martine; Lanoue, Arnaud; Dugé de Bernonville, Thomas; Besseau, Sébastien; Glévarec, Gaëlle; Papon, Nicolas; Atehortúa, Lucia; Giglioli-Guivarc'h, Nathalie; Clastre, Marc; St-Pierre, Benoit; Oudin, Audrey; Courdavault, Vincent

    2017-07-01

    Elucidation of the monoterpene indole alkaloid biosynthesis has recently progressed in Apocynaceae through the concomitant development of transcriptomic analyses and reverse genetic approaches performed by virus-induced gene silencing (VIGS). While most of these tools have been primarily adapted for the Madagascar periwinkle (Catharanthus roseus), the VIGS procedure has scarcely been used on other Apocynaceae species. For instance, Rauwolfia sp. constitutes a unique source of specific and valuable monoterpene indole alkaloids such as the hypertensive reserpine but are also well recognized models for studying alkaloid metabolism, and as such would benefit from an efficient VIGS procedure. By taking advantage of a recent modification in the inoculation method of the Tobacco rattle virus vectors via particle bombardment, we demonstrated that the biolistic-mediated VIGS approach can be readily used to silence genes in both Rauwolfia tetraphylla and Rauwolfia serpentina. After establishing the bombardment conditions minimizing injuries to the transformed plantlets, gene downregulation efficiency was evaluated at approximately a 70% expression decrease in both species by silencing the phytoene desaturase encoding gene. Such a gene silencing approach will thus constitute a critical tool to identify and characterize genes involved in alkaloid biosynthesis in both of these prominent Rauwolfia species.

  18. Occurrence of virus-induced COPD exacerbations during four seasons.

    PubMed

    Djamin, Remco S; Uzun, Sevim; Snelders, Eveline; Kluytmans, Jan J W; Hoogsteden, Henk C; Aerts, Joachim G J V; Van Der Eerden, Menno M

    2015-02-01

    In this study, we investigated the occurrence of viral infections in acute exacerbations of chronic obstructive pulmonary disease (COPD) during four seasons. Viral infections were detected by the use of real-time reverse transcriptase polymerase chain reaction on pharyngeal swabs. During a 12-month period pharyngeal swabs were obtained in 136 exacerbations of 63 patients. In 35 exacerbations (25.7%) a viral infection was detected. Most viral infections occurred in the winter (n = 14, 40.0%), followed by summer (n = 9, 25.7%), autumn (n = 6, 17.1%), and spring (n = 6, 17.1%). Rhinovirus was the most frequently isolated virus (n = 19, 51.4%), followed by respiratory syncytial virus (n = 6, 16.2%), human metapneumovirus (n = 5, 13.5%), influenza A (n = 4, 10.8%), parainfluenza 4 (n = 2, 5.4%), and parainfluenza 3 (n = 1, 2.7%). This study showed that virus-induced COPD exacerbations occur in all four seasons with a peak in the winter months. However, the distribution of rhinovirus infections showed a different pattern, with most infections occurring in July.

  19. Virus-Induced Silencing of a Plant Cellulose Synthase Gene

    PubMed Central

    Burton, Rachel A.; Gibeaut, David M.; Bacic, Antony; Findlay, Kim; Roberts, Keith; Hamilton, Andrew; Baulcombe, David C.; Fincher, Geoffrey B.

    2000-01-01

    Specific cDNA fragments corresponding to putative cellulose synthase genes (CesA) were inserted into potato virus X vectors for functional analysis in Nicotiana benthamiana by using virus-induced gene silencing. Plants infected with one group of cDNAs had much shorter internode lengths, small leaves, and a “dwarf” phenotype. Consistent with a loss of cell wall cellulose, abnormally large and in many cases spherical cells ballooned from the undersurfaces of leaves, particularly in regions adjacent to vascular tissues. Linkage analyses of wall polysaccharides prepared from infected leaves revealed a 25% decrease in cellulose content. Transcript levels for at least one member of the CesA cellulose synthase gene family were lower in infected plants. The decrease in cellulose content in cell walls was offset by an increase in homogalacturonan, in which the degree of esterification of carboxyl groups decreased from ∼50 to ∼33%. The results suggest that feedback loops interconnect the cellular machinery controlling cellulose and pectin biosynthesis. On the basis of the phenotypic features of the infected plants, changes in wall composition, and the reduced abundance of CesA mRNA, we concluded that the cDNA fragments silenced one or more cellulose synthase genes. PMID:10810144

  20. Fluorescence spectroscopic detection of virus-induced atherosclerosis

    NASA Astrophysics Data System (ADS)

    Yan, Wei-dong; Perk, Masis; Nation, Patric N.; Power, Robert F.; Liu, Liying; Jiang, Xiuyan; Lucas, Alexandra

    1994-07-01

    Laser-induced fluorescence (LF) has been developed as a diagnostic tool for the detection of atherosclerosis. We have examined the use of LF for the identification of accelerated atherosclerotic plaque growth induced by Marek's Disease Virus (MDV) infection in White Leghorn rooster chicks (R) as well as plaque regression after treatment. Twenty-eight newborn R were infected with 12,000 cfu of MDV. Twelve parallel control R had saline injection. LF spectra were recorded from the arteries in vitro with a CeramOptec laser angioplasty catheter during 308 nm XeCl excimer laser excitation. Significant differences were detected at 440 to 475, 525, 550, 600, and 650 nm in MDV-R (p<0.05). In a subsequent study, 60 R were infected with 5,000 cfu of MDV, and were then treated with either Pravastatin (PRV) or placebo at 3 months post infection. These PRV-R were followed for 6 months to detect changes in atherosclerotic plaque development. PRV reduced intimal proliferation produced by MDV infection on histological examination (PRV-R 128.0+/- 44.0 micrometers , placebo-R 412.2+/- 91.5 micrometers , pequals0.007). MDV infected, PRV treated R were examined for LF changes that correlated with decreased atherosclerosis. There was an associated significant increase in LF intensity in PRV-R at 405 to 425 nm (p<0.001). In conclusion, LF can detect intimal proliferation in virus- induced atherosclerosis and atherosclerotic plaque regression after PRV therapy.

  1. Nutrigenomics Therapy of Hepatisis C Virus Induced-hepatosteatosis

    PubMed Central

    2010-01-01

    Nutrigenomics is a relatively new branch of nutrition science, which aim is to study the impact of the foods we eat on the function of our genes. Hepatosteatosis is strongly associated with hepatitis C virus infection, which is known to increase the risk of the disease progression and reduce the likelihood of responding to anti- virus treatment. It is well documented that hepatitis C virus can directly alter host cell lipid metabolism through nuclear transcription factors. To date, only a limited number of studies have been on the effect of human foods on the nuclear transcription factors of hepatitis C virus -induced hepatosteatosis. Three nutrients, selected among 46 different nutrients: β-carotene, vitamin D2, and linoleic acid were found in a cell culture system to inhibit hepatitis C virus RNA replication. In addition, polyunsaturated fatty acids (PUFAs) especially arachidonic acid (AA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) have been demonstrated to inhibit hepatitis C virus RNA replication. These PUFAs, in particular the highly unsaturated n-3 fatty acids change the gene expression of PPARa and SREBP, suppress the expression of mRNAs encoding key metabolic enzymes and hereby suppress hepatic lipogenesis and triglyceride synthesis, as well as secretion and accumulation in tissues. A recent prospective clinical trial of 1,084 chronic hepatitis C patients compared to 2,326 healthy subjects suggests that chronic hepatitis C patients may benefit from strict dietary instructions. Increasing evidence suggest that some crucial nuclear transcription factors related to hepatitis C virus -associated hepatosteatosis and hepatitis C virus RNA itself can be controlled by specific anti- hepatitis C virus nutrition. It seems important that these findings are taken into account and specific nutritional supplements developed to be used in combination with interferon as adjunctive therapy with the aim to improve both the early as well as the sustained

  2. Nutrigenomics therapy of hepatisis C virus induced-hepatosteatosis.

    PubMed

    Liu, Qing; Bengmark, Stig; Qu, Shen

    2010-05-20

    Nutrigenomics is a relatively new branch of nutrition science, which aim is to study the impact of the foods we eat on the function of our genes. Hepatosteatosis is strongly associated with hepatitis C virus infection, which is known to increase the risk of the disease progression and reduce the likelihood of responding to anti- virus treatment. It is well documented that hepatitis C virus can directly alter host cell lipid metabolism through nuclear transcription factors. To date, only a limited number of studies have been on the effect of human foods on the nuclear transcription factors of hepatitis C virus -induced hepatosteatosis.Three nutrients, selected among 46 different nutrients: beta-carotene, vitamin D2, and linoleic acid were found in a cell culture system to inhibit hepatitis C virus RNA replication. In addition, polyunsaturated fatty acids (PUFAs) especially arachidonic acid (AA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) have been demonstrated to inhibit hepatitis C virus RNA replication. These PUFAs, in particular the highly unsaturated n-3 fatty acids change the gene expression of PPARa and SREBP, suppress the expression of mRNAs encoding key metabolic enzymes and hereby suppress hepatic lipogenesis and triglyceride synthesis, as well as secretion and accumulation in tissues. A recent prospective clinical trial of 1,084 chronic hepatitis C patients compared to 2,326 healthy subjects suggests that chronic hepatitis C patients may benefit from strict dietary instructions.Increasing evidence suggest that some crucial nuclear transcription factors related to hepatitis C virus -associated hepatosteatosis and hepatitis C virus RNA itself can be controlled by specific anti- hepatitis C virus nutrition. It seems important that these findings are taken into account and specific nutritional supplements developed to be used in combination with interferon as adjunctive therapy with the aim to improve both the early as well as the sustained

  3. Understanding Leukemia

    MedlinePlus

    ... a microscope. Bone marrow biopsy I A very small amount of bone filled with marrow cells is removed through a needle. The cells are then looked at under a microscope. Each main type of leukemia also has different subtypes . In other words, patients ...

  4. Childhood Cancer: Leukemia (For Parents)

    MedlinePlus

    ... acute. Acute childhood leukemias are also divided into acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) , depending on ... Bone Marrow Childhood Cancer Neutropenia Stem Cell Transplants Acute Lymphoblastic Leukemia (ALL) Chemotherapy Radiation Therapy Chronic Myelogenous Leukemia (CML) ...

  5. Chronic Myelogenous Leukemia

    MedlinePlus

    Chronic myelogenous leukemia Overview Chronic myelogenous leukemia (CML) is an uncommon type of cancer of the blood cells. The term "chronic" in chronic myelogenous leukemia indicates that this cancer ...

  6. Big fusion, little fusion

    NASA Astrophysics Data System (ADS)

    Chen, Frank; ddtuttle

    2016-08-01

    In reply to correspondence from George Scott and Adam Costley about the Physics World focus issue on nuclear energy, and to news of construction delays at ITER, the fusion reactor being built in France.

  7. Increased tumor necrosis factor-alpha (TNF-alpha) gene expression in parainfluenza type 1 (Sendai) virus-induced bronchiolar fibrosis.

    PubMed Central

    Uhl, E. W.; Moldawer, L. L.; Busse, W. W.; Jack, T. J.; Castleman, W. L.

    1998-01-01

    Increased airway resistance and airway hyperresponsiveness induced in rats by infection with parainfluenza type I (Sendai) virus is associated with bronchiolar fibrosis. To determine whether increased tumor necrosis factor (TNF)-alpha gene expression is an important regulatory event in virus-induced bronchiolar fibrosis, pulmonary TNF-alpha mRNA and protein expression was assessed in rat strains that are susceptible (Brown Norway; BN) and resistant (Fischer 344; F344) to virus-induced bronchiolar fibrosis. Virus-inoculated BN rats had increased TNF-alpha pulmonary mRNA levels (P < 0.05) and increased numbers of bronchiolar macrophages and fibroblasts expressing TNF-alpha protein compared with virus-inoculated F344 rats (P < 0.05). Virus inoculation also induced elevated TNF-alpha mRNA and protein levels (P < 0.05) in cultured rat alveolar macrophages (NR8383 cells). A 55-kd soluble TNF receptor-immunoglobulin G fusion protein (sTNFR-IgG) was used to inhibit TNF-alpha bioactivity in virus-inoculated BN rats. Treated rats had fewer proliferating bronchiolar fibroblasts, as detected by bromodeoxyuridine incorporation, compared with virus-inoculated control rats (P < 0.05). There was also increased mortality in p55sTNFR-IgG-treated virus-inoculated rats associated with increased viral replication and decreased numbers of macrophages and lymphocytes in bronchoalveolar lavage fluid (P < 0.05). The results of this study indicate that 1) Sendai virus can directly up-regulate TNF-alpha mRNA and protein expression in macrophages, 2) TNF-alpha is an important mediator of virus-induced bronchiolar fibrosis, and 3) TNF-alpha has a critical role in the termination of Sendai viral replication in the lung. Images Figure 2 PMID:9466578

  8. Sequences responsible for erythroid and lymphoid leukemia in the long terminal repeats of Friend-mink cell focus-forming and Moloney murine leukemia viruses.

    PubMed Central

    Ishimoto, A; Takimoto, M; Adachi, A; Kakuyama, M; Kato, S; Kakimi, K; Fukuoka, K; Ogiu, T; Matsuyama, M

    1987-01-01

    Despite the high degree of homology (91%) between the nucleotide sequences of the Friend-mink cell focus-forming (MCF) and the Moloney murine leukemia virus (MuLV) genomic long terminal repeats (LTRs), the pathogenicities determined by the LTR sequences of the two viruses are quite different. Friend-MCF MuLV is an erythroid leukemia virus, and Moloney MuLV is a lymphoid leukemia virus. To map the LTR sequences responsible for the different disease specificities, we constructed nine viruses with LTRs recombinant between the Friend-MCF and Moloney MuLVs. Analysis of the leukemia induced with the recombinant viruses showed that a 195-base-pair nucleotide sequence, including a 75-base-pair nucleotide Moloney enhancer, is responsible for the tissue-specific leukemogenicity of Moloney MuLV. However, not only the enhancer but also its downstream sequences appear to be necessary. The Moloney virus enhancer and its downstream sequence exerted a dominant effect over that of the Friend-MCF virus, but the enhancer sequence alone did not. The results that three of the nine recombinant viruses induced both erythroid and lymphoid leukemias supported the hypothesis that multiple viral genetic determinants control both the ability to cause leukemia and the type of leukemia induced. PMID:3033317

  9. Acute myelogenous leukemia cells with the MLL-ELL translocation convert morphologically and functionally into adherent myofibroblasts

    SciTech Connect

    Tashiro, Haruko; Mizutani-Noguchi, Mitsuho; Shirasaki, Ryosuke

    2010-01-01

    Bone marrow-myofibroblasts, a major component of bone marrow-stroma, are reported to originate from hematopoietic stem cells. We show in this paper that non-adherent leukemia blasts can change into myofibroblasts. When myeloblasts from two cases of acute myelogenous leukemia with a fusion product comprising mixed lineage leukemia and RNA polymerase II elongation factor, were cultured long term, their morphology changed to that of myofibroblasts with similar molecular characteristics to the parental myeloblasts. The original leukemia blasts, when cultured on the leukemia blast-derived myofibroblasts, grew extensively. Leukemia blasts can create their own microenvironment for proliferation.

  10. Simple multiplex RT-PCR for identifying common fusion BCR-ABL transcript types and evaluation of molecular response of the a2b2 and a2b3 transcripts to Imatinib resistance in north Indian chronic myeloid leukemia patients.

    PubMed

    Mir, Rashid; Ahmad, I; Javid, J; Zuberi, M; Yadav, P; Shazia, R; Masroor, M; Guru, S; Ray, P C; Gupta, N; Saxena, A

    2015-01-01

    Chronic myeloid leukemia (CML) is characterized by the Philadelphia chromosome, an abnormally shortened chromosome 22. It is the result of a reciprocal translocation of chromosomes 9 and 22, creating BCR-ABL fusion transcripts, b3a2, b2a2, and e1a2. The aim of our study was to determine the type of BCR-ABL fusion transcripts for molecular diagnosis and investigate the frequency of BCR-ABL fusion transcripts in CML patients by multiplex RT-PCR in CML. A single reaction with multiple primers multiplex PCR was used to detect and investigate the type and frequency in 200 CML patients among which 116, 33, and 51 were in CP, AP, and BC phase, respectively. The study included 200 CML patients, among whom breakpoints in b3a2, b2a2 transcripts were detected in 68% and 24%, respectively, while 8% of the patients showed both b3a2/b2a2. A statistically significant difference was seen between frequency of BCR-ABL fusion transcripts and gender (P = 0.03), molecular response (P = 0.04), and hematological response (P = 0.05). However, there was no correlation found between frequencies of BCR-/ABL fusion transcripts and other clinicopathological parameters like age, type of therapy, thrombocytopenia, and white blood cell count. Multiplex reverse transcriptase-polymerase chain reaction is useful and saves time in the detection of BCR-ABL variants; the occurrence of these transcripts associated with CML can assist in prognosis and treatment of disease.

  11. MLL-Rearranged Leukemias-An Update on Science and Clinical Approaches.

    PubMed

    Winters, Amanda C; Bernt, Kathrin M

    2017-01-01

    The mixed-lineage leukemia 1 (MLL1) gene (now renamed Lysine [K]-specific MethylTransferase 2A or KMT2A) on chromosome 11q23 is disrupted in a unique group of acute leukemias. More than 80 different partner genes in these fusions have been described, although the majority of leukemias result from MLL1 fusions with one of about six common partner genes. Approximately 10% of all leukemias harbor MLL1 translocations. Of these, two patient populations comprise the majority of cases: patients younger than 1 year of age at diagnosis (primarily acute lymphoblastic leukemias) and young- to-middle-aged adults (primarily acute myeloid leukemias). A much rarer subgroup of patients with MLL1 rearrangements develop leukemia that is attributable to prior treatment with certain chemotherapeutic agents-so-called therapy-related leukemias. In general, outcomes for all of these patients remain poor when compared to patients with non-MLL1 rearranged leukemias. In this review, we will discuss the normal biological roles of MLL1 and its fusion partners, how these roles are hypothesized to be dysregulated in the context of MLL1 rearrangements, and the clinical manifestations of this group of leukemias. We will go on to discuss the progress in clinical management and promising new avenues of research, which may lead to more effective targeted therapies for affected patients.

  12. Leukemia revisited

    SciTech Connect

    Cronkite, E P

    1980-01-01

    Selected features of the historical development of our knowledge of leukemia are discussed. The use of different methodologies for study of the nature of leukemic cell proliferation are analyzed. The differences between older cell kinetic data using tritiated thymidine and autoradiography and the newer cell culture methods are more apparent than real. It is suggested that tritiated thymidine and extracorporeal irradiation of the blood may be useful for therapeutic agents that have not been given an adequate trial. Radiation leukemogenesis presents an opportunity for study of the nature of leukemogenesis that has not been exploited adequately.

  13. The leukemias: Epidemiologic aspects

    SciTech Connect

    Linet, M.S.

    1984-01-01

    Particularly geared to physicians and cancer researchers, this study of the epidemiology and etiology of leukemia analyzes the four major leukemia subtypes in terms of genetic and familial determinant factors and examines the incidence, distribution and frequency of reported leukemia clusters. Linet discusses the connection between other types of malignancies, their treatments, and the subsequent development of leukemia and evaluates the impact on leukemia onset of such environmental factors as radiation therapy, drugs, and occupational hazards.

  14. Virus-induced hepatocellular carcinoma with special emphasis on HBV.

    PubMed

    Wang, Ming; Xi, Dong; Ning, Qin

    2017-03-01

    Hepatocellular carcinoma (HCC) is a common malignant tumor with high lethality, and the hepatitis B virus (HBV) is a chief cause. HBV can accelerate HCC via multiple mechanisms. First, HBV induces immune reactions that lead to repeated hepatic inflammation, fibrosis and a deficient immune microenvironment. Subsequently, HBV can modify host genes near the insertion point through DNA integration to cause host cell genome instability and to generate carcinogenic fusion proteins. Additionally, HBV expresses diverse active proteins, especially HBx and HBs, which have a range of transactivation functions such as regulation of apoptosis, interference with intracellular signaling pathways, and alteration of epigenetics. Currently, primary prevention measures for HBV-induced HCC focus on vaccination and antiviral treatment. Here, we report the epidemiology, the molecular mechanism and the progress in therapeutic strategies for controlling HBV-induced HCC.

  15. Decitabine in Treating Children With Relapsed or Refractory Acute Myeloid Leukemia or Acute Lymphoblastic Leukemia

    ClinicalTrials.gov

    2013-01-22

    Childhood Acute Myeloblastic Leukemia With Maturation (M2); Childhood Acute Promyelocytic Leukemia (M3); Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Acute Myeloid Leukemia; Secondary Acute Myeloid Leukemia

  16. An accurate and rapid flow cytometric diagnosis of BCR-ABL positive acute lymphoblastic leukemia

    PubMed Central

    Raponi, Sara; De Propris, Maria Stefania; Wai, Hobert; Intoppa, Stefania; Elia, Loredana; Diverio, Daniela; Vitale, Antonella; Foà, Robin; Guarini, Anna

    2009-01-01

    Tyrosine kinase inhibitors have profoundly modified the treatment and prognosis of chronic myeloid leukemia and Ph+ acute lymphoblastic leukemia. A rapid and accurate detection of the BCR-ABL fusion protein is paramount today for an optimal management of Ph+ acute lymphoblastic leukemia. We have utilized a recently described and commercialized immunoassay that identifies qualitatively the presence of the BCR-ABL protein in leukemic cell lysates. The BCR-ABL fusion protein is captured and detected by a cytometric bead assay and analyzed by flow cytometry. The assay was applied to 101 primary patient samples (94 acute leukemias and 7 chronic myeloid leukemia blast crisis) and the results of the immunoassay were concordant with those obtained by conventional molecular techniques. The method proved reliable, reproducible, of simple execution and it was successfully completed within four hours. This flow cytometric immunoassay has important implications for perfecting the management of Ph+ acute lymphoblastic leukemia patients worldwide. PMID:19608682

  17. TRV Based Virus Induced Gene Silencing in Gladiolus (Gladiolus grandiflorus L.), A Monocotyledonous Ornamental Plant

    USDA-ARS?s Scientific Manuscript database

    Virus-induced gene silencing (VIGS) has not yet successfully been used as a tool for gene functional analysis in non-grass monocotyledonous geophytes. We therefore tested VIGS in gladiolus (Gladiolus grandiflora L) using a Tobacco Rattle Virus (TRV) vector containing a fragment of the gladiolus gene...

  18. Virus-induced gene silencing in cultivated cotton (Gossypium spp.) using Tobacco rattle virus

    USDA-ARS?s Scientific Manuscript database

    The study described here has optimized the conditions for virus induced gene silencing (VIGS) in three cultivated cotton species (Gossypium hirsutum, G. arboreum and G. herbaceum) using a Tobacco rattle virus (TRV) vector. The system was used to silence the homolog of the Arabidopsis thaliana chloro...

  19. IDENTITY OF "INHIBITOR" AND ANTIBODY IN EXTRACTS OF VIRUS-INDUCED RABBIT PAPILLOMAS

    PubMed Central

    Friedewald, William F.

    1940-01-01

    The "inhibitor" demonstrable in extracts of the virus-induced rabbit papillomas is identical with the antiviral antibody found in the blood of hosts bearing the growths. The conditions in these latter are frequently favorable to its extravasation in considerable amount into them. Its significance and its influence upon the recovery of virus from the papillomas are discussed. PMID:19871016

  20. Virus induced gene silencing of Arabidopsis gene homologues in wheat identify genes conferring improved drought tolerance

    USDA-ARS?s Scientific Manuscript database

    In a non-model staple crop like wheat, functional validation of potential drought stress responsive genes identified in Arabidopsis could provide gene targets for wheat breeding. Virus induced gene silencing (VIGS) of genes of interest can overcome the inherent problems of polyploidy and limited tra...

  1. Childhood Cancer: Leukemia (For Parents)

    MedlinePlus

    ... Habits for TV, Video Games, and the Internet Leukemia KidsHealth > For Parents > Leukemia Print A A A ... Causes Symptoms Diagnosis Treatment en español Leucemia About Leukemia The term leukemia refers to cancers of the ...

  2. What Is Chronic Lymphocytic Leukemia?

    MedlinePlus

    ... About Chronic Lymphocytic Leukemia What Is Chronic Lymphocytic Leukemia? Cancer starts when cells in the body begin ... the lymph nodes, liver, and spleen. What is leukemia? Leukemia is a cancer that starts in the ...

  3. What Is Chronic Myeloid Leukemia?

    MedlinePlus

    ... About Chronic Myeloid Leukemia What Is Chronic Myeloid Leukemia? Cancer starts when cells in the body begin ... is the same as for adults. What is leukemia? Leukemia is a cancer that starts in the ...

  4. Acute promyelocytic leukemia: new issues on pathogenesis and treatment response.

    PubMed

    Vitoux, Dominique; Nasr, Rihab; de The, Hugues

    2007-01-01

    Pathogenesis of acute promyelocytic leukemia appears to be one of the best understood among human malignancies. The ability of retinoic acid (RA) and arsenic trioxide to directly target the oncogenic promyelocytic leukemia-retinoic receptor A (PML-RARA) fusion protein also made this disease the first model for oncogene-targeted therapies. A set of recent data has significantly increased the complexity of our view of acute promyelocytic leukemia pathogenesis, as well as of therapeutic response. This review summarizes and discusses these findings, which yield novels questions and models.

  5. Moloney murine leukemia virus activates NF-kappa B.

    PubMed Central

    Pak, J; Faller, D V

    1996-01-01

    Nonacutely transforming retroviruses, such as Moloney murine leukemia virus (M-MuLV), differ from transforming viruses in their mechanisms of tumor induction. While the transforming viruses cause tumors by transduction of oncogenes, the leukemia retroviruses, lacking oncogenes, employ other mechanisms, including promoter insertion and enhancer activation. Although these two mechanisms occur in many tumors induced by leukemia viruses, a substantial proportion of such tumors do not show site-specific proviral insertions. Thus, other, unidentified virus-driven mechanisms may participate in tumorigenesis. In these studies, we show that infection of cells by M-MuLV activates expression of Rel family transcription factors. In murine cells chronically infected with M-MuLV, gel shift analyses with kappaB DNA-binding motifs from the murine immunoglobulin kappa light chain enhancer demonstrated induction of at least two distinct kappaB enhancer-binding complexes. Supershifting and immunoblotting analyses defined p50, p52, RelB, and c-Rel subunits as constituents of these virus-induced protein complexes. Transient transfections performed with kappaB-dependent reporter plasmids showed transcriptional activation in M-MuLV-infected cells relative to uninfected cells. Induction of Rel/NF-kappaB transcription factor activity by M-MuLV infection may prove relevant to the mechanism of M-MuLV-induced leukemia. PMID:8648762

  6. Measles virus-induced suppression of immune responses

    PubMed Central

    Griffin, Diane E.

    2010-01-01

    Summary Measles is an important cause of child mortality that has a seemingly paradoxical interaction with the immune system. In most individuals, the immune response is successful in eventually clearing measles virus (MV) infection and in establishing life-long immunity. However, infection is also associated with persistence of viral RNA and several weeks of immune suppression, including loss of delayed type hypersensitivity responses and increased susceptibility to secondary infections. The initial T-cell response includes CD8+ and T-helper 1 CD4+ T cells important for control of infectious virus. As viral RNA persists, there is a shift to a T-helper 2 CD4+ T-cell response that likely promotes B-cell maturation and durable antibody responses but may suppress macrophage activation and T-helper 1 responses to new infections. Suppression of mitogen-induced lymphocyte proliferation can be induced by lymphocyte infection with MV or by lymphocyte exposure to a complex of the hemagglutinin and fusion surface glycoproteins without infection. Dendritic cells are susceptible to infection and can transmit infection to lymphocytes. MV-infected dendritic cells are unable to stimulate a mixed lymphocyte reaction and can induce lymphocyte unresponsiveness through expression of MV glycoproteins. Thus, multiple factors may contribute both to measles-induced immune suppression and to the establishment of durable protective immunity. PMID:20636817

  7. Supportive Care for Chronic Lymphocytic Leukemia

    MedlinePlus

    ... Chronic Lymphocytic Leukemia Supportive Care for Chronic Lymphocytic Leukemia Supportive care for chronic lymphocytic leukemia (CLL) is ... Treating Hairy Cell Leukemia More In Chronic Lymphocytic Leukemia About Chronic Lymphocytic Leukemia Causes, Risk Factors, and ...

  8. MLL-ENL-mediated leukemia initiation at the interface of lymphoid commitment.

    PubMed

    Ugale, A; Säwén, P; Dudenhöffer-Pfeifer, M; Wahlestedt, M; Norddahl, G L; Bryder, D

    2017-06-01

    Translocations involving the mixed lineage leukemia-1 are recurrent events in acute leukemia and associate with lymphoid (ALL), myeloid (AML) or mixed lineage (MLL) subtypes. Despite an association with ALL in humans, murine MLL fusion models are persistently restricted to AML. We here explored this issue using an inducible mixed lineage leukemia-eleven nineteen leukemia (MLL-ENL) mouse model. Although multiple progenitor cell types with myeloid potential are potent AML leukemia-initiating cells, also the earliest lymphoid progenitors were capable of initiating AML. This ability to evoke a latent myeloid potential in the earliest lymphoid progenitors was lost upon further lymphoid commitment. At the same time, more downstream/committed lymphoid precursors also failed to initiate lymphoid leukemia. Co-expression of MLL-ENL with a constitutively active RAS allele, the most common co-mutation in MLL fusion leukemias, could influence on both disease latency and lineage assignment of developing leukemia in what appears to be a mutation-order-dependent manner. Finally, CEBPB-mediated transdifferentation of committed and otherwise leukemia-incompetent B-cell progenitors imbued these cells with leukemic competence for AML. Therefore, apart from providing detailed insight into the differential responsiveness of candidate target cells to a first-hit MLL fusion event, our data warrants caution to therapeutic approaches based on the concept of transdifferentiation.

  9. Spinal Fusion

    MedlinePlus

    ... concept of fusion is similar to that of welding in industry. Spinal fusion surgery, however, does not ... bone taken from the patient has a long history of use and results in predictable healing. Autograft ...

  10. Spinal Fusion

    MedlinePlus

    ... concept of fusion is similar to that of welding in industry. Spinal fusion surgery, however, does not ... bone taken from the patient has a long history of use and results in predictable healing. Autograft ...

  11. Leukemia & Lymphoma Society

    MedlinePlus

    ... Light The Night Man & Woman of the Year Leukemia Cup Regatta Student Series Lifestyle Community Careers at ... Special Projects Beat AML Patients & caregivers Disease Information Leukemia Lymphoma Myeloma Myelodysplastic Syndromes Myeloproliferative Neoplasms Childhood Blood ...

  12. Acute Myeloid Leukemia

    MedlinePlus

    Leukemia is cancer of the white blood cells. White blood cells help your body fight infection. Your blood cells form in your bone marrow. In leukemia, however, the bone marrow produces abnormal white blood ...

  13. Acute Lymphocytic Leukemia

    MedlinePlus

    Leukemia is cancer of the white blood cells. White blood cells help your body fight infection. Your blood cells form in your bone marrow. In leukemia, however, the bone marrow produces abnormal white blood ...

  14. Chronic Myeloid Leukemia

    MedlinePlus

    Leukemia is cancer of the white blood cells. White blood cells help your body fight infection. Your blood cells form in your bone marrow. In leukemia, the bone marrow produces abnormal white blood cells. ...

  15. Chronic Lymphocytic Leukemia

    MedlinePlus

    Leukemia is cancer of the white blood cells. White blood cells help your body fight infection. Your blood cells form in your bone marrow. In leukemia, the bone marrow produces abnormal white blood cells. ...

  16. Acute Lymphocytic Leukemia

    MedlinePlus

    ... treatment of acute lymphoblastic leukemia in children. In: Hematology: Basic Principles and Practice. 6th ed. Philadelphia, Pa.: ... et al. Acute lymphoblastic leukemia in adults. In: Hematology: Basic Principles and Practice. 6th ed. Philadelphia, Pa.: ...

  17. Leukemia: stem cells, maturation arrest, and differentiation therapy.

    PubMed

    Sell, Stewart

    2005-01-01

    Human myeloid leukemias provide models of maturation arrest and differentiation therapy of cancer. The genetic lesions of leukemia result in a block of differentiation (maturation arrest) that allows myeloid leukemic cells to continue to proliferate and/or prevents the terminal differentiation and apoptosis seen in normal white blood cells. In chronic myeloid leukemia, the bcr-abl (t9/22) translocation produces a fusion product that is an activated tyrosine kinase resulting in constitutive activation cells at the myelocyte level. This activation may be inhibited by imatinib mesylate (Gleevec, STI-571), which blocks the binding of ATP to the activated tyrosine kinase, prevents phosphorylation, and allows the leukemic cells to differentiate and undergo apoptosis. In acute promyelocytic leukemia, fusion of the retinoic acid receptor-alpha with the gene coding for promyelocytic protein, the PML-RAR alpha (t15:17) translocation, produces a fusion product that blocks the activity of the promyelocytic protein, which is required for formation of the granules of promyelocytes and prevents further differentiation. Retinoic acids bind to the retinoic acid receptor (RAR alpha) component of the fusion product, resulting in degradation of the fusion protein by ubiquitinization. This allows normal PML to participate in granule formation and differentiation of the promyelocytes. In one common type of acute myeloid leukemia, which results in maturation arrest at the myeloid precursor level, there is a mutation of FLT3, a transmembrane tyrosine kinase, which results in constitutive activation of the IL-3 receptor. This may be blocked by agents that inhibit farnesyl transferase. In each of these examples, specific inhibition of the genetically altered activation molecules of the leukemic cells allows the leukemic cells to differentiate and die. Because acute myeloid leukemias usually have mutation of more than one gene, combinations of specific inhibitors that act on the effects of

  18. 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

  19. 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. Copyright© Ferrata Storti Foundation.

  20. MicroRNA miR-125b causes leukemia.

    PubMed

    Bousquet, Marina; Harris, Marian H; Zhou, Beiyan; Lodish, Harvey F

    2010-12-14

    MicroRNA miR-125b has been implicated in several kinds of leukemia. The chromosomal translocation t(2;11)(p21;q23) found in patients with myelodysplasia and acute myeloid leukemia leads to an overexpression of miR-125b of up to 90-fold normal. Moreover, miR-125b is also up-regulated in patients with B-cell acute lymphoblastic leukemia carrying the t(11;14)(q24;q32) translocation. To decipher the presumed oncogenic mechanism of miR-125b, we used transplantation experiments in mice. All mice transplanted with fetal liver cells ectopically expressing miR-125b showed an increase in white blood cell count, in particular in neutrophils and monocytes, associated with a macrocytic anemia. Among these mice, half died of B-cell acute lymphoblastic leukemia, T-cell acute lymphoblastic leukemia, or a myeloproliferative neoplasm, suggesting an important role for miR-125b in early hematopoiesis. Furthermore, coexpression of miR-125b and the BCR-ABL fusion gene in transplanted cells accelerated the development of leukemia in mice, compared with control mice expressing only BCR-ABL, suggesting that miR-125b confers a proliferative advantage to the leukemic cells. Thus, we show that overexpression of miR-125b is sufficient both to shorten the latency of BCR-ABL-induced leukemia and to independently induce leukemia in a mouse model.

  1. Radioscapholunate Fusions

    PubMed Central

    McGuire, Duncan Thomas; Bain, Gregory Ian

    2012-01-01

    Radiocarpal fusions are performed for a variety of indications, most commonly for debilitating painful arthritis. The goal of a wrist fusion is to fuse the painful, diseased joints and to preserve motion through the healthy joints. Depending on the extent of the disease process, radiocarpal fusions may take the form of radiolunate, radioscapholunate, or total wrist fusions. Surgical techniques and instrumentation have advanced over the last few decades, and consequently the functional outcomes have improved and complications decreased. Techniques for partial carpal fusions have improved and now include distal scaphoid and triquetrum excision, which improves range of motion and fusion rates. In this article we discuss the various surgical techniques and fixation methods available and review the corresponding evidence in the literature. The authors' preferred surgical technique of radioscapholunate fusion with distal scaphoid and triquetrum excision is outlined. New implants and new concepts are also discussed. PMID:24179717

  2. Persistence of TEL-AML1 fusion gene as minimal residual disease has no additive prognostic value in CD 10 positive B-acute lymphoblastic leukemia: a FISH study

    PubMed Central

    Mosad, Eman; Hamed, Hosny B; Bakry, Rania M; Ezz-Eldin, Azza M; Khalifa, Nesrine M

    2008-01-01

    Objectives We have analyzed t(12;21)(p13:q22) in an attempt to evaluate the frequency and prognostic significance of TEL-AML1 fusion gene in patients with childhood CD 10 positive B-ALL by fluorescence in situ hybridization (FISH). Also, we have monitored the prognostic value of this gene as a minimal residual disease (MRD). Methods All bone marrow samples of eighty patients diagnosed as CD 10 positive B-ALL in South Egypt Cancer Institute were evaluated by fluorescence in situ hybridization (FISH) for t(12;21) in newly diagnosed cases and after morphological complete remission as a minimal residual disease (MRD). We determined the prognostic significance of TEL-AML1 fusion represented by disease course and survival. Results TEL-AML1 fusion gene was positive in (37.5%) in newly diagnosed patients. There was a significant correlation between TEL-AML1 fusion gene both at diagnosis (r = 0.5, P = 0.003) and as a MRD (r = 0.4, P = 0.01) with favorable course. Kaplan-Meier curve for the presence of TEL-AML1 fusion at the diagnosis was associated with a better probability of overall survival (OS); mean survival time was 47 ± 1 month, in contrast to 28 ± 5 month in its absence (P = 0.006). Also, the persistence at TEL-AML1 fusion as a MRD was not significantly associated with a better probability of OS; the mean survival time was 42 ± 2 months in the presence of MRD and it was 40 ± 1 months in its absence. So, persistence of TEL-AML1 fusion as a MRD had no additive prognostic value over its measurement at diagnosis in terms of predicting the probability of OS. Conclusion For most patients, the presence of TEL-AML1 fusion gene at diagnosis suggests a favorable prognosis. The present study suggests that persistence of TEL-AML1 fusion as MRD has no additive prognostic value. PMID:18928518

  3. Exhaled breath temperature increases during mild exacerbations in children with virus-induced asthma.

    PubMed

    Xepapadaki, P; Xatziioannou, A; Chatzicharalambous, M; Makrinioti, H; Papadopoulos, N G

    2010-01-01

    Exhaled breath temperature (EBT) has been suggested as a non-invasive surrogate marker of airway inflammation in asthma. The aim of the study was to evaluate differences in EBT between periods of controlled disease and during exacerbations in children with virus-induced asthma. Twenty-nine children (aged 6-14 years) with a history of intermittent, virus-induced asthma were included in this case-control study. Cases presented with a common cold and/or mild exacerbation of asthma, while controls were free of asthmatic or common cold symptoms during the previous 6 weeks. A baseline questionnaire was obtained. Atopy assessment, central temperature and a spirometric measurement were recorded. EBT was measured with a new device (Delmedica, Singapore). A nasal wash (for identification of common respiratory viruses) was obtained. Twenty-four children (12 from each group) completed the study. Groups were homogeneous with respect to baseline characteristics. PCR revealed the presence of a virus in 3 out of 17 controls and 10 out of 12 cases (17.6 and 83.3%, respectively, p = 0.002). The most commonly identified virus was rhinovirus (3/3 controls and 7/10 cases, p = 0.02). EBT values were significantly higher for cases (34.91 +/- 0.62 degrees C) compared to controls (34.18 +/- 1.1 degrees C, p = 0.032). No important differences were observed in the increase rate of EBT (Deltae degrees T) between groups. Changes in airway inflammation during virus-induced asthma exacerbations are reflected in EBT changes. These preliminary data suggest a possible role of EBT measurements in the assessment of airway inflammation in children with virus-induced asthma. Copyright (c) 2010 S. Karger AG, Basel.

  4. Heparin prevents Zika virus induced-cytopathic effects in human neural progenitor cells.

    PubMed

    Ghezzi, Silvia; Cooper, Lynsay; Rubio, Alicia; Pagani, Isabel; Capobianchi, Maria Rosaria; Ippolito, Giuseppe; Pelletier, Julien; Meneghetti, Maria Cecilia Z; Lima, Marcelo A; Skidmore, Mark A; Broccoli, Vania; Yates, Edwin A; Vicenzi, Elisa

    2017-04-01

    The recent Zika virus (ZIKV) outbreak, which mainly affected Brazil and neighbouring states, demonstrated the paucity of information concerning the epidemiology of several flaviruses, but also highlighted the lack of available agents with which to treat such emerging diseases. Here, we show that heparin, a widely used anticoagulant, while exerting a modest inhibitory effect on Zika Virus replication, fully prevents virus-induced cell death of human neural progenitor cells (NPCs).

  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. AMKL chimeric transcription factors are potent inducers of leukemia.

    PubMed

    Dang, J; Nance, S; Ma, J; Cheng, J; Walsh, M P; Vogel, P; Easton, J; Song, G; Rusch, M; Gedman, A L; Koss, C; Downing, J R; Gruber, T A

    2017-03-10

    Acute megakaryoblastic leukemia in patients without Down syndrome is a rare malignancy with a poor prognosis. RNA sequencing of fourteen pediatric cases previously identified novel fusion transcripts that are predicted to be pathological including CBFA2T3-GLIS2, GATA2-HOXA9, MN1-FLI and NIPBL-HOXB9. In contrast to CBFA2T3-GLIS2, which is insufficient to induce leukemia, we demonstrate that the introduction of GATA2-HOXA9, MN1-FLI1 or NIPBL-HOXB9 into murine bone marrow induces overt disease in syngeneic transplant models. With the exception of MN1, full penetrance was not achieved through the introduction of fusion partner genes alone, suggesting that the chimeric transcripts possess a unique gain-of-function phenotype. Leukemias were found to exhibit elements of the megakaryocyte erythroid progenitor gene expression program, as well as unique leukemia-specific signatures that contribute to transformation. Comprehensive genomic analyses of resultant murine tumors revealed few cooperating mutations confirming the strength of the fusion genes and their role as pathological drivers. These models are critical for both the understanding of the biology of disease as well as providing a tool for the identification of effective therapeutic agents in preclinical studies.Leukemia advance online publication, 10 March 2017; doi:10.1038/leu.2017.51.

  7. IP-10 Is Elevated in Virus-Induced Acute Exacerbations in Childhood Asthma.

    PubMed

    Suzuki, Kazuo; Kato, Masahiko; Matsuda, Shinichi; Nukaga, Mariko; Enseki, Mayumi; Tabata, Hideyuki; Hirai, Kota; Yamada, Yoshiyuki; Maruyama, Kenichi; Hayashi, Yasuhide; Mochizuki, Hiroyuki

    2016-12-20

    Viral infections and sensitization to aeroallergens are major factors in the exacerbation of asthma and its development during early childhood. However, the cytokine profiles and eosinophil activation status linked to the association between viral infections and sensitization to aeroallergens are incompletely understood. Here we investigated respiratory viruses, serum eosinophil cationic protein (ECP), and various cytokines/chemokines in acute exacerbation of childhood asthma. We analyzed peripheral eosinophil counts, serum ECP, and 27 cytokines/chemokines in 76 virus-induced acute asthma cases with or without aeroallergen sensitization. Asthma due to sensitization was defined by a positive reaction to at least one aeroallergen in serum specific IgE antibody tests. Virus detection was performed using antigen detection kits and/or RT-PCR, followed by direct DNA sequencing analysis. Serum cytokines/chemokines were measured using a multi-cytokine detection system. Peripheral eosinophil counts and serum ECP and IL-5 levels were significantly elevated in sensitized cases compared with nonsensitized cases. Conversely, IP-10 values were significantly higher in nonsensitized cases. An inverse correlation between IP-10 and IL-5 production was identified in virus-induced acute exacerbations of asthma but not in controls. Cytokine profiles and eosinophil activation status might be different between sensitized and nonsensitized cases of virus-induced acute exacerbations of asthma.

  8. Influenza Virus Induces Inflammatory Response in Mouse Primary Cortical Neurons with Limited Viral Replication.

    PubMed

    Wang, Gefei; Li, Rui; Jiang, Zhiwu; Gu, Liming; Chen, Yanxia; Dai, Jianping; Li, Kangsheng

    2016-01-01

    Unlike stereotypical neurotropic viruses, influenza A viruses have been detected in the brain tissues of human and animal models. To investigate the interaction between neurons and influenza A viruses, mouse cortical neurons were isolated, infected with human H1N1 influenza virus, and then examined for the production of various inflammatory molecules involved in immune response. We found that replication of the influenza virus in neurons was limited, although early viral transcription was not affected. Virus-induced neuron viability decreased at 6 h postinfection (p.i.) but increased at 24 h p.i. depending upon the viral strain. Virus-induced apoptosis and cytopathy in primary cortical neurons were not apparent at 24 h p.i. The mRNA levels of inflammatory cytokines, chemokines, and type I interferons were upregulated at 6 h and 24 h p.i. These results indicate that the influenza virus induces inflammatory response in mouse primary cortical neurons with limited viral replication. The cytokines released in viral infection-induced neuroinflammation might play critical roles in influenza encephalopathy, rather than in viral replication-induced cytopathy.

  9. Transcription factor RUNX1 promotes survival of acute myeloid leukemia cells

    PubMed Central

    Goyama, Susumu; Schibler, Janet; Cunningham, Lea; Zhang, Yue; Rao, Yalan; Nishimoto, Nahoko; Nakagawa, Masahiro; Olsson, Andre; Wunderlich, Mark; Link, Kevin A.; Mizukawa, Benjamin; Grimes, H. Leighton; Kurokawa, Mineo; Liu, P. Paul; Huang, Gang; Mulloy, James C.

    2013-01-01

    RUNX1 is generally considered a tumor suppressor in myeloid neoplasms. Inactivating RUNX1 mutations have frequently been found in patients with myelodysplastic syndrome (MDS) and cytogenetically normal acute myeloid leukemia (AML). However, no somatic RUNX1 alteration was found in AMLs with leukemogenic fusion proteins, such as core-binding factor (CBF) leukemia and MLL fusion leukemia, raising the possibility that RUNX1 could actually promote the growth of these leukemia cells. Using normal human cord blood cells and those expressing leukemogenic fusion proteins, we discovered a dual role of RUNX1 in myeloid leukemogenesis. RUNX1 overexpression inhibited the growth of normal cord blood cells by inducing myeloid differentiation, whereas a certain level of RUNX1 activity was required for the growth of AML1-ETO and MLL-AF9 cells. Using a mouse genetic model, we also showed that the combined loss of Runx1/Cbfb inhibited leukemia development induced by MLL-AF9. RUNX2 could compensate for the loss of RUNX1. The survival effect of RUNX1 was mediated by BCL2 in MLL fusion leukemia. Our study unveiled an unexpected prosurvival role for RUNX1 in myeloid leukemogenesis. Inhibiting RUNX1 activity rather than enhancing it could be a promising therapeutic strategy for AMLs with leukemogenic fusion proteins. PMID:23979164

  10. Fusion breeder

    SciTech Connect

    Moir, R.W.

    1982-04-20

    The fusion breeder is a fusion reactor designed with special blankets to maximize the transmutation by 14 MeV neutrons of uranium-238 to plutonium or thorium to uranium-233 for use as a fuel for fission reactors. Breeding fissile fuels has not been a goal of the US fusion energy program. This paper suggests it is time for a policy change to make the fusion breeder a goal of the US fusion program and the US nuclear energy program. The purpose of this paper is to suggest this policy change be made and tell why it should be made, and to outline specific research and development goals so that the fusion breeder will be developed in time to meet fissile fuel needs.

  11. Fusion breeder

    SciTech Connect

    Moir, R.W.

    1982-02-22

    The fusion breeder is a fusion reactor designed with special blankets to maximize the transmutation by 14 MeV neutrons of uranium-238 to plutonium or thorium to uranium-233 for use as a fuel for fission reactors. Breeding fissile fuels has not been a goal of the US fusion energy program. This paper suggests it is time for a policy change to make the fusion breeder a goal of the US fusion program and the US nuclear energy program. The purpose of this paper is to suggest this policy change be made and tell why it should be made, and to outline specific research and development goals so that the fusion breeder will be developed in time to meet fissile fuel needs.

  12. "Polarized" Fusion

    NASA Astrophysics Data System (ADS)

    Schieck, Hans Paetz Gen.

    Increasing energy demand in view of limited supply, as well as environmental and nuclear-safety concerns leading to increased emphasis on renewable energy sources such as solar or wind energy are expected to focus public and scientific interest increasingly also on fusion energy. With the decision to build ITER (low-density magnetic confinement) and also continuing research on (high-density) inertial-confinement fusion (cf. the inauguration of the laser fusion facility at the Lawrence Livermore National Laboratory) prospects of fusion energy have probably entered a new era.

  13. Plasma fusion and cold fusion

    SciTech Connect

    Hideo, Kozima

    1996-12-31

    Fundamental problems of plasma fusion (controlled thermonuclear fusion) due to the contradicting demands of the magnetic confinement of plasma and suppression of instabilities occurring on and in plasma are surveyed in contrast with problems of cold fusion. Problems in cold fusion due to the complicated constituents and types of force are explained. Typical cold fusion events are explained by a model based on the presence of trapped neutrons in cold fusion materials. The events include Pons-Fleishmann effect, tritium anomaly, helium 4 production, and nuclear transmutation. Fundamental hypothesis of the model is an effectiveness of a new concept--neutron affinity of elements. The neutron affinity is defined and some bases supporting it are explained. Possible justification of the concept by statistical approach is given.

  14. What You Need to Know about Leukemia

    MedlinePlus

    ... Publications Reports What You Need To Know About™ Leukemia This booklet is about leukemia. Leukemia is cancer of the blood and bone marrow ( ... This book covers: Basics about blood cells and leukemia Types of doctors who treat leukemia Treatments for ...

  15. Targeted Therapy for Acute Lymphocytic Leukemia

    MedlinePlus

    ... Adults Treating Acute Lymphocytic Leukemia Targeted Therapy for Acute Lymphocytic Leukemia In recent years, new drugs that target specific ... Typical Treatment of Acute Lymphocytic Leukemia More In Acute Lymphocytic Leukemia About Acute Lymphocytic Leukemia Causes, Risk Factors, and ...

  16. What Is Acute Lymphocytic Leukemia (ALL)?

    MedlinePlus

    ... Adults About Acute Lymphocytic Leukemia (ALL) What Is Acute Lymphocytic Leukemia? Cancer starts when cells in the body begin ... Acute Lymphocytic Leukemia Research and Treatment? More In Acute Lymphocytic Leukemia About Acute Lymphocytic Leukemia Causes, Risk Factors, and ...

  17. A high-throughput virus-induced gene-silencing vector for screening transcription factors in virus-induced plant defense response in orchid.

    PubMed

    Lu, Hsiang-Chia; Hsieh, Ming-Hsien; Chen, Cheng-En; Chen, Hong-Hwa; Wang, Hsiang-Iu; Yeh, Hsin-Hung

    2012-06-01

    The large number of species and worldwide spread of species of Orchidaceae indicates their successful adaptation to environmental stresses. Thus, orchids provide rich resources to study how plants have evolved to cope with stresses. This report describes our improvement of our previously reported orchid virus-induced gene silencing vector, pCymMV-pro60, with a modified Gateway cloning system which requires only one recombination and can be inoculated by agroinfiltration. We cloned 1,700 DNA fragments, including 187 predicted transcription factors derived from an established expression sequence tag library of orchid, into pCymMV-Gateway. Phalaenopsis aphrodite was inoculated with these vectors that contained DNA fragments of the 187 predicted transcription factors. The viral vector initially triggered the expression of the salicylic acid (SA)-related plant defense responses and later induced silencing of the endogenous target transcription factor genes. By monitoring the expression of the SA-related plant defense marker PhaPR1 (homolog of PR1), we identified a gene, PhaTF15, involved in the expression of PhaPR1. Knockdown of PhaTF15 by virus-induced gene silencing and by transient delivery of double-stranded RNA (dsRNA) reduced expression of the orchid homolog of the conserved positive defense regulator NPR1, PhaNPR1. Cymbidium mosaic virus also accumulated to high levels with knockdown of PhaTF15 by transient delivery of dsRNA. We demonstrated efficient cloning and screening strategies for high-throughput analysis of orchid and identify a gene, PhaTF15, involved in regulation of SA-related plant defense.

  18. Image fusion

    NASA Technical Reports Server (NTRS)

    Pavel, M.

    1993-01-01

    The topics covered include the following: a system overview of the basic components of a system designed to improve the ability of a pilot to fly through low-visibility conditions such as fog; the role of visual sciences; fusion issues; sensor characterization; sources of information; image processing; and image fusion.

  19. Acute myeloid leukemia induced by MLL-ENL is cured by oncogene ablation despite acquisition of complex genetic abnormalities.

    PubMed

    Horton, Sarah J; Walf-Vorderwülbecke, Vanessa; Chatters, Steve J; Sebire, Neil J; de Boer, Jasper; Williams, Owen

    2009-05-14

    Chromosomal translocations involving 11q23 are frequent in infant acute leukemia and give rise to the formation of MLL fusion genes. The mechanism of leukemic transformation by these fusions has been the subject of numerous investigations. However, the dependence of acute leukemia on MLL fusion activity in vivo and the efficacy of targeting this activity to eliminate disease have not been established. We have developed a model for conditional expression of MLL-ENL in hematopoietic progenitor cells, in which expression of the fusion oncogene is turned off by doxycycline. Conditionally immortalized myeloblast cells derived from these progenitors were found to induce leukemia in vivo. Leukemic cells isolated from primary recipient mice were shown to have acquired additional genetic abnormalities and, when transplanted into secondary recipients, induced leukemia with shortened latencies. However, the leukemic cells remained dependent on MLL-ENL expression in vitro and in vivo, and its ablation resulted in regression of established leukemias. This study demonstrates that even genetically complex leukemias can be reversed on inactivation of the initiating MLL fusion and has important implications for the design of novel leukemia therapies.

  20. Flavopiridol, Cytarabine, and Mitoxantrone in Treating Patients With Acute Leukemia

    ClinicalTrials.gov

    2013-10-07

    Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Secondary Acute Myeloid Leukemia; Untreated Adult Acute Lymphoblastic Leukemia; Untreated Adult Acute Myeloid Leukemia

  1. [Hairy cell leukemia].

    PubMed

    Dietrich, S; Andrulis, M; Zenz, T

    2015-04-01

    Hairy cell leukemia was initially described as a distinct entity in 1958. It is rare B-cell malignancy characterized by an indolent course. Advances in the treatment and understanding of the biology of hairy cell leukemia have made the disease exquisitely amenable to treatment. This review summarizes the present understanding of hairy cell leukemia with a particular focus on the development of novel and targeted approaches to treatment.

  2. EGFR activation suppresses respiratory virus-induced IRF1-dependent CXCL10 production.

    PubMed

    Kalinowski, April; Ueki, Iris; Min-Oo, Gundula; Ballon-Landa, Eric; Knoff, David; Galen, Benjamin; Lanier, Lewis L; Nadel, Jay A; Koff, Jonathan L

    2014-07-15

    Airway epithelial cells are the primary cell type involved in respiratory viral infection. Upon infection, airway epithelium plays a critical role in host defense against viral infection by contributing to innate and adaptive immune responses. Influenza A virus, rhinovirus, and respiratory syncytial virus (RSV) represent a broad range of human viral pathogens that cause viral pneumonia and induce exacerbations of asthma and chronic obstructive pulmonary disease. These respiratory viruses induce airway epithelial production of IL-8, which involves epidermal growth factor receptor (EGFR) activation. EGFR activation involves an integrated signaling pathway that includes NADPH oxidase activation of metalloproteinase, and EGFR proligand release that activates EGFR. Because respiratory viruses have been shown to activate EGFR via this signaling pathway in airway epithelium, we investigated the effect of virus-induced EGFR activation on airway epithelial antiviral responses. CXCL10, a chemokine produced by airway epithelial cells in response to respiratory viral infection, contributes to the recruitment of lymphocytes to target and kill virus-infected cells. While respiratory viruses activate EGFR, the interaction between CXCL10 and EGFR signaling pathways is unclear, and the potential for EGFR signaling to suppress CXCL10 has not been explored. Here, we report that respiratory virus-induced EGFR activation suppresses CXCL10 production. We found that influenza virus-, rhinovirus-, and RSV-induced EGFR activation suppressed IFN regulatory factor (IRF) 1-dependent CXCL10 production. In addition, inhibition of EGFR during viral infection augmented IRF1 and CXCL10. These findings describe a novel mechanism that viruses use to suppress endogenous antiviral defenses, and provide potential targets for future therapies.

  3. EGFR activation suppresses respiratory virus-induced IRF1-dependent CXCL10 production

    PubMed Central

    Kalinowski, April; Ueki, Iris; Min-Oo, Gundula; Ballon-Landa, Eric; Knoff, David; Galen, Benjamin; Lanier, Lewis L.; Nadel, Jay A.

    2014-01-01

    Airway epithelial cells are the primary cell type involved in respiratory viral infection. Upon infection, airway epithelium plays a critical role in host defense against viral infection by contributing to innate and adaptive immune responses. Influenza A virus, rhinovirus, and respiratory syncytial virus (RSV) represent a broad range of human viral pathogens that cause viral pneumonia and induce exacerbations of asthma and chronic obstructive pulmonary disease. These respiratory viruses induce airway epithelial production of IL-8, which involves epidermal growth factor receptor (EGFR) activation. EGFR activation involves an integrated signaling pathway that includes NADPH oxidase activation of metalloproteinase, and EGFR proligand release that activates EGFR. Because respiratory viruses have been shown to activate EGFR via this signaling pathway in airway epithelium, we investigated the effect of virus-induced EGFR activation on airway epithelial antiviral responses. CXCL10, a chemokine produced by airway epithelial cells in response to respiratory viral infection, contributes to the recruitment of lymphocytes to target and kill virus-infected cells. While respiratory viruses activate EGFR, the interaction between CXCL10 and EGFR signaling pathways is unclear, and the potential for EGFR signaling to suppress CXCL10 has not been explored. Here, we report that respiratory virus-induced EGFR activation suppresses CXCL10 production. We found that influenza virus-, rhinovirus-, and RSV-induced EGFR activation suppressed IFN regulatory factor (IRF) 1-dependent CXCL10 production. In addition, inhibition of EGFR during viral infection augmented IRF1 and CXCL10. These findings describe a novel mechanism that viruses use to suppress endogenous antiviral defenses, and provide potential targets for future therapies. PMID:24838750

  4. The role of macrophage IL-10/innate IFN interplay during virus-induced asthma

    PubMed Central

    Zdrenghea, Mihnea T; Makrinioti, Heidi; Muresan, Adriana; Johnston, Sebastian L; Stanciu, Luminita A

    2015-01-01

    Activation through different signaling pathways results in two functionally different types of macrophages, the pro-inflammatory (M1) and the anti-inflammatory (M2). The polarization of macrophages toward the pro-inflammatory M1 phenotype is considered to be critical for efficient antiviral immune responses in the lung. Among the various cell types that are present in the asthmatic airways, macrophages have emerged as significant participants in disease pathogenesis, because of their activation during both the inflammatory and resolution phases, with an impact on disease progression. Polarized M1 and M2 macrophages are able to reversibly undergo functional redifferentiation into anti-inflammatory or pro-inflammatory macrophages, respectively, and therefore, macrophages mediate both processes. Recent studies have indicated a predominance of M2 macrophages in asthmatic airways. During a virus infection, it is likely that M2 macrophages would secrete higher amounts of the suppressor cytokine IL-10, and less innate IFNs. However, the interactions between IL-10 and innate IFNs during virus-induced exacerbations of asthma have not been well studied. The possible role of IL-10 as a therapy in allergic asthma has already been suggested, but the divergent roles of this suppressor molecule in the antiviral immune response raise concerns. This review attempts to shed light on macrophage IL-10–IFNs interactions and discusses the role of IL-10 in virus-induced asthma exacerbations. Whereas IL-10 is important in terminating pro-inflammatory and antiviral immune responses, the presence of this immune regulatory cytokine at the beginning of virus infection could impair the response to viruses and play a role in virus-induced asthma exacerbations. PMID:25430775

  5. PU.1 is essential for MLL leukemia partially via crosstalk with the MEIS/HOX pathway

    PubMed Central

    Zhou, J; Wu, J; Li, B; Liu, D; Yu, J; Yan, X; Zheng, S; Wang, J; Zhang, L; Zhang, L; He, F; Li, Q; Chen, A; Zhang, Y; Zhao, X; Guan, Y; Zhao, X; Yan, J; Ni, J; Nobrega, MA; Löwenberg, B; Delwel, R; Valk, PJM; Kumar, A; Xie, L; Tenen, DG; Huang, G; Wang, Q-f

    2015-01-01

    Mixed lineage leukemia (MLL) fusion proteins directly activate the expression of key downstream genes such as MEIS1, HOXA9 to drive an aggressive form of human leukemia. However, it is still poorly understood what additional transcriptional regulators, independent of the MLL fusion pathway, contribute to the development of MLL leukemia. Here we show that the transcription factor PU.1 is essential for MLL leukemia and is required for the growth of MLL leukemic cells via the promotion of cell-cycle progression and inhibition of apoptosis. Importantly, PU.1 expression is not under the control of MLL fusion proteins. We further identified a PU.1-governed 15-gene signature, which contains key regulators in the MEIS-HOX program (MEIS1, PBX3, FLT3, and c-KIT). PU.1 directly binds to the genomic loci of its target genes in vivo, and is required to maintain active expression of those genes in both normal hematopoietic stem and progenitor cells and in MLL leukemia. Finally, the clinical significance of the identified PU.1 signature was indicated by its ability to predict survival in acute myelogenous leukemia patients. Together, our findings demonstrate that PU.1 contributes to the development of MLL leukemia, partially via crosstalk with the MEIS/HOX pathway. PMID:24445817

  6. MR VIGS: microRNA-based virus-induced gene silencing in plants.

    PubMed

    Chen, Weiwei; Zhang, Qi; Kong, Junhua; Hu, Feng; Li, Bin; Wu, Chaoqun; Qin, Cheng; Zhang, Pengcheng; Shi, Nongnong; Hong, Yiguo

    2015-01-01

    In plants, microRNA (miRNA)-based virus-induced gene silencing, dubbed MR VIGS, is a powerful technique to delineate the biological functions of genes. By targeting to a specific sequence, miRNAs can knock down expression of genes with fewer off-target effects. Here, using a modified Cabbage leaf curling virus (CaLCuV) and Tobacco rattle virus (TRV) as vectors, we describe two virus-based miRNA expression systems to perform MR VIGS for plant functional genomics assays.

  7. THE EFFECT OF CHEMICAL CARCINOGENS ON VIRUS-INDUCED RABBIT PAPILLOMAS

    PubMed Central

    Rous, Peyton; Friedewald, William F.

    1944-01-01

    The application of methylcholanthrene and tar to virus-induced papillomas of the domestic rabbit caused them to become carcinomatous with great rapidity, and the malignant changes were frequently multiple. In bringing on the cancers the chemical agents acted in their specific capacity as carcinogens, not as ordinary stimulants of cell proliferation. The cancers derived from the virus-infected cells and were of the same types as arise from these elements spontaneously after a much longer time. The evidence would seem to indicate that the chemical carcinogens acted by way of the virus. PMID:19871385

  8. Flavopiridol in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia, Acute Lymphoblastic Leukemia, or Chronic Myelogenous Leukemia

    ClinicalTrials.gov

    2013-06-03

    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); Blastic Phase Chronic Myelogenous Leukemia; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Relapsing Chronic Myelogenous Leukemia

  9. [Extramedullary onset of mixed phenotype acute leukemia with MLL gene rearrangement].

    PubMed

    Kawashima, Ichiro; Shobu, Yuki; Yamamoto, Takeo; Hamanaka, Satoshi; Nozaki, Yumi; Nakajima, Kei; Mitsumori, Toru; Kirito, Keita

    2013-03-01

    Rearrangements of the mixed lineage leukemia MLL gene at chromosome 11q23 are common chromosomal abnormalities in human leukemia. MLL fused with numerous partner genes causes different leukemia phenotypes that depend on the function of partner genes. MLLT3-MLL is generated by translocation t(9;11), which primarily induces acute myeloid leukemia in humans, whereas MLLT3-MLL induces ALL or biphenotypic leukemia in mice. The microenvironment that surrounds leukemia cells plays a central role in this process. We report a patient with mixed phenotype acute leukemia with MLLT3-MLL. This patient, a 44-year-old woman, initially exhibited extramedullary leukemia with multiple tumors and subsequently developed bone marrow disease. The leukemia cells exhibited myeloid (CD13 and MPO) and B cell (CD19 and CD79a) phenotypes. Chromosomal analysis and RT-PCR assay revealed tumor cells with the MLLT3-MLL fusion gene. We treated this patient with a drug regimen for AML (Ara-C plus anthracycline), and complete remission was obtained. This report describes the fourth case of mixed phenotypic leukemia with extramedullary disease. The extramedullary circumstance may underlie the biphenotypic features of these patients.

  10. The MLL recombinome of acute leukemias in 2017.

    PubMed

    Meyer, C; Burmeister, T; Gröger, D; Tsaur, G; Fechina, L; Renneville, A; Sutton, R; Venn, N C; Emerenciano, M; Pombo-de-Oliveira, M S; Barbieri Blunck, C; Almeida Lopes, B; Zuna, J; Trka, J; Ballerini, P; Lapillonne, H; De Braekeleer, M; Cazzaniga, G; Corral Abascal, L; van der Velden, V H J; Delabesse, E; Park, T S; Oh, S H; Silva, M L M; Lund-Aho, T; Juvonen, V; Moore, A S; Heidenreich, O; Vormoor, J; Zerkalenkova, E; Olshanskaya, Y; Bueno, C; Menendez, P; Teigler-Schlegel, A; Zur Stadt, U; Lentes, J; Göhring, G; Kustanovich, A; Aleinikova, O; Schäfer, B W; Kubetzko, S; Madsen, H O; Gruhn, B; Duarte, X; Gameiro, P; Lippert, E; Bidet, A; Cayuela, J M; Clappier, E; Alonso, C N; Zwaan, C M; van den Heuvel-Eibrink, M M; Izraeli, S; Trakhtenbrot, L; Archer, P; Hancock, J; Möricke, A; Alten, J; Schrappe, M; Stanulla, M; Strehl, S; Attarbaschi, A; Dworzak, M; Haas, O A; Panzer-Grümayer, R; Sedék, L; Szczepański, T; Caye, A; Suarez, L; Cavé, H; Marschalek, R

    2017-07-13

    Chromosomal rearrangements of the human MLL/KMT2A gene are associated with infant, pediatric, adult and therapy-induced acute leukemias. Here we present the data obtained from 2345 acute leukemia patients. Genomic breakpoints within the MLL gene and the involved translocation partner genes (TPGs) were determined and 11 novel TPGs were identified. Thus, a total of 135 different MLL rearrangements have been identified so far, of which 94 TPGs are now characterized at the molecular level. In all, 35 out of these 94 TPGs occur recurrently, but only 9 specific gene fusions account for more than 90% of all illegitimate recombinations of the MLL gene. We observed an age-dependent breakpoint shift with breakpoints localizing within MLL intron 11 associated with acute lymphoblastic leukemia and younger patients, while breakpoints in MLL intron 9 predominate in AML or older patients. The molecular characterization of MLL breakpoints suggests different etiologies in the different age groups and allows the correlation of functional domains of the MLL gene with clinical outcome. This study provides a comprehensive analysis of the MLL recombinome in acute leukemia and demonstrates that the establishment of patient-specific chromosomal fusion sites allows the design of specific PCR primers for minimal residual disease analyses for all patients.Leukemia advance online publication, 8 August 2017; doi:10.1038/leu.2017.213.

  11. New insights to the MLL recombinome of acute leukemias.

    PubMed

    Meyer, C; Kowarz, E; Hofmann, J; Renneville, A; Zuna, J; Trka, J; Ben Abdelali, R; Macintyre, E; De Braekeleer, E; De Braekeleer, M; Delabesse, E; de Oliveira, M P; Cavé, H; Clappier, E; van Dongen, J J M; Balgobind, B V; van den Heuvel-Eibrink, M M; Beverloo, H B; Panzer-Grümayer, R; Teigler-Schlegel, A; Harbott, J; Kjeldsen, E; Schnittger, S; Koehl, U; Gruhn, B; Heidenreich, O; Chan, L C; Yip, S F; Krzywinski, M; Eckert, C; Möricke, A; Schrappe, M; Alonso, C N; Schäfer, B W; Krauter, J; Lee, D A; Zur Stadt, U; Te Kronnie, G; Sutton, R; Izraeli, S; Trakhtenbrot, L; Lo Nigro, L; Tsaur, G; Fechina, L; Szczepanski, T; Strehl, S; Ilencikova, D; Molkentin, M; Burmeister, T; Dingermann, T; Klingebiel, T; Marschalek, R

    2009-08-01

    Chromosomal rearrangements of the human MLL gene are associated with high-risk pediatric, adult and therapy-associated acute leukemias. These patients need to be identified, treated appropriately and minimal residual disease was monitored by quantitative PCR techniques. Genomic DNA was isolated from individual acute leukemia patients to identify and characterize chromosomal rearrangements involving the human MLL gene. A total of 760 MLL-rearranged biopsy samples obtained from 384 pediatric and 376 adult leukemia patients were characterized at the molecular level. The distribution of MLL breakpoints for clinical subtypes (acute lymphoblastic leukemia, acute myeloid leukemia, pediatric and adult) and fused translocation partner genes (TPGs) will be presented, including novel MLL fusion genes. Combined data of our study and recently published data revealed 104 different MLL rearrangements of which 64 TPGs are now characterized on the molecular level. Nine TPGs seem to be predominantly involved in genetic recombinations of MLL: AFF1/AF4, MLLT3/AF9, MLLT1/ENL, MLLT10/AF10, MLLT4/AF6, ELL, EPS15/AF1P, MLLT6/AF17 and SEPT6, respectively. Moreover, we describe for the first time the genetic network of reciprocal MLL gene fusions deriving from complex rearrangements.

  12. Fusion Power.

    ERIC Educational Resources Information Center

    Dingee, David A.

    1979-01-01

    Discusses the extraordinary potential, the technical difficulties, and the financial problems that are associated with research and development of fusion power plants as a major source of energy. (GA)

  13. Fusion Power.

    ERIC Educational Resources Information Center

    Dingee, David A.

    1979-01-01

    Discusses the extraordinary potential, the technical difficulties, and the financial problems that are associated with research and development of fusion power plants as a major source of energy. (GA)

  14. The Family Leukemia Association

    ERIC Educational Resources Information Center

    Pollitt, Eleanor

    1976-01-01

    An association of families of children with leukemia, the Family Leukemia Association (FLA), was recently established in Toronto. This paper discusses (a) philosophy of the FLA; (b) formative years of this organization; (c) problems encountered by leukemic children and their families; and (d) the FLA's past and future educational and social…

  15. The Family Leukemia Association

    ERIC Educational Resources Information Center

    Pollitt, Eleanor

    1976-01-01

    An association of families of children with leukemia, the Family Leukemia Association (FLA), was recently established in Toronto. This paper discusses (a) philosophy of the FLA; (b) formative years of this organization; (c) problems encountered by leukemic children and their families; and (d) the FLA's past and future educational and social…

  16. [Acute plasma cell leukemia].

    PubMed

    Monsalbe, V; Domíngues, C; Roa, I; Busel, D; González, S

    1989-01-01

    Plasma Cell Leukemia is a very rare form of plasmocytic dyscrasia, whose clinical and pathological characteristics warrant its recognition as a distinct subentity. We report the case of a 60 years old man who presented a rapidly fatal acute plasma cell leukemia, with multiple osteolytic lesions, hipercalcemia, renal and cardiac failure.

  17. Virus-induced gene complementation reveals a transcription factor network in modulation of tomato fruit ripening

    PubMed Central

    Zhou, Tao; Zhang, Hang; Lai, Tongfei; Qin, Cheng; Shi, Nongnong; Wang, Huizhong; Jin, Mingfei; Zhong, Silin; Fan, Zaifeng; Liu, Yule; Wu, Zirong; Jackson, Stephen; Giovannoni, James J.; Rolin, Dominique; Gallusci, Philippe; Hong, Yiguo

    2012-01-01

    Plant virus technology, in particular virus-induced gene silencing, is a widely used reverse- and forward-genetics tool in plant functional genomics. However the potential of virus technology to express genes to induce phenotypes or to complement mutants in order to understand the function of plant genes is not well documented. Here we exploit Potato virus X as a tool for virus-induced gene complementation (VIGC). Using VIGC in tomato, we demonstrated that ectopic viral expression of LeMADS-RIN, which encodes a MADS-box transcription factor (TF), resulted in functional complementation of the non-ripening rin mutant phenotype and caused fruits to ripen. Comparative gene expression analysis indicated that LeMADS-RIN up-regulated expression of the SBP-box (SQUAMOSA promoter binding protein-like) gene LeSPL-CNR, but down-regulated the expression of LeHB-1, an HD-Zip homeobox TF gene. Our data support the hypothesis that a transcriptional network may exist among key TFs in the modulation of fruit ripening in tomato. PMID:23150786

  18. Respiratory syncytial virus infection and virus-induced inflammation are modified by contaminants of indoor air

    PubMed Central

    Foster, Serene; Bedford, Kirk J; Gould, Melanie E L; Coward, William R; Hewitt, Colin R A

    2003-01-01

    The airway epithelium is the first cellular component of the lung to be encountered by the particles and pathogens present in inhaled air. In addition to its role as a physical barrier, the immunological activity of the airway epithelium is an essential part of the pulmonary immune system. This means that the symptoms of lung diseases that involve immunological mechanisms are frequently exacerbated by infection of the airway epithelium with respiratory viruses. The virus-induced enhancement of immunological activity in infected epithelial cells is well characterized. However, the effects that contaminants of inhaled air have upon the infectivity and replication of respiratory viruses and the inflammation they cause, are comparatively unknown. In this study, we have shown that pre-exposure of airway epithelial cells to bacterial lipopolysaccharides or a proteolytically active house dust mite allergen, is able to, respectively, inhibit or enhance the level of cellular infection with respiratory syncytial virus and similarly alter virus-induced expression of the inflammatory chemokine interleukin-8. These results suggest that respiratory syncytial virus infection and the inflammation caused by respiratory syncytial virus may be modified by the biologically active contaminants of indoor air. PMID:12519309

  19. Fludarabine Phosphate and Total-Body Irradiation Before Donor Peripheral Blood Stem Cell Transplant in Treating Patients With Chronic Lymphocytic Leukemia or Small Lymphocytic Leukemia

    ClinicalTrials.gov

    2016-07-18

    B-Cell Prolymphocytic Leukemia; Chronic Lymphocytic Leukemia; Prolymphocytic Leukemia; Recurrent Chronic Lymphocytic Leukemia; Recurrent Small Lymphocytic Lymphoma; Refractory Chronic Lymphocytic Leukemia; T-Cell Prolymphocytic Leukemia

  20. Acute promyelocytic leukemia, arsenic, and PML bodies

    PubMed Central

    Le Bras, Morgane; Lallemand-Breitenbach, Valérie

    2012-01-01

    Acute promyelocytic leukemia (APL) is driven by a chromosomal translocation whose product, the PML/retinoic acid (RA) receptor α (RARA) fusion protein, affects both nuclear receptor signaling and PML body assembly. Dissection of APL pathogenesis has led to the rediscovery of PML bodies and revealed their role in cell senescence, disease pathogenesis, and responsiveness to treatment. APL is remarkable because of the fortuitous identification of two clinically effective therapies, RA and arsenic, both of which degrade PML/RARA oncoprotein and, together, cure APL. Analysis of arsenic-induced PML or PML/RARA degradation has implicated oxidative stress in the biogenesis of nuclear bodies and SUMO in their degradation. PMID:22778276

  1. Leukemia Cutis Associated with Secondary Plasma Cell Leukemia.

    PubMed

    DeMartinis, Nicole C; Brown, Megan M; Hinds, Brian R; Cohen, Philip R

    2017-05-09

    Plasma cell leukemia is an uncommon, aggressive variant of leukemia that may occur de novo or in association with multiple myeloma. Leukemia cutis is the cutaneous manifestation of leukemia, and indicates an infiltration of the skin by malignant leukocytes or their precursors. Plasma cell leukemia cutis is a rare clinical presentation of leukemia. We present a man who developed plasma cell leukemia cutis in association with multiple myeloma. Cutaneous nodules developed on his arms and legs 50 days following an autologous stem cell transplant. Histopathologic examination showed CD138-positive nodular aggregates of atypical plasma cells with kappa light chain restriction, similar to the phenotype of his myeloma. In spite of systemic treatment of his underlying disease, he died 25 days after the presentation of leukemia cutis. Pub-Med was searched for the following terms: cutaneous plasmacytomas, leukemia cutis, plasma cell leukemia nodules, plasma cell leukemia cutis, and secondary cutaneous plasmacytoma. Papers were reviewed and appropriate references evaluated. Leukemia cutis in plasma cell leukemia patients is an infrequent occurrence. New skin lesions in patients with plasma cell leukemia should be biopsied for pathology and for tissue cultures to evaluate for cancer or infection, respectively. The diagnosis plasma cell leukemia cutis is associated with a very poor prognosis.

  2. Characterization of the Rana grylio virus 3{beta}-hydroxysteroid dehydrogenase and its novel role in suppressing virus-induced cytopathic effect

    SciTech Connect

    Sun Wei; Huang Youhua; Zhao Zhe; Gui Jianfang; Zhang Qiya . E-mail: zhangqy@ihb.ac.cn

    2006-12-08

    The 3{beta}-hydroxysteroid dehydrogenase (3{beta}-HSD) isoenzymes play a key role in cellular steroid hormone synthesis. Here, a 3{beta}-HSD gene homolog was cloned from Rana grylio virus (RGV), a member of family Iridoviridae. RGV 3{beta}-HSD gene has 1068 bp, encoding a 355 aa predicted protein. Transcription analyses showed that RGV 3{beta}-HSD gene was transcribed immediate-early during infection from an initiation site 19 nucleotides upstream of the translation start site. Confocal microscopy revealed that the 3{beta}-HSD-EGFP fusion protein was exclusively colocalized with the mitochondria marker (pDsRed2-Mito) in EPC cells. Upon morphological observation and MTT assay, it was revealed that overexpression of RGV 3{beta}-HSD in EPC cells could apparently suppress RGV-induced cytopathic effect (CPE). The present studies indicate that the RGV immediate-early 3{beta}-HSD gene encodes a mitochondria-localized protein, which has a novel role in suppressing virus-induced CPE. All these suggest that RGV 3{beta}-HSD might be a protein involved in host-virus interaction.

  3. Mechanism of ETV6-RUNX1 Leukemia.

    PubMed

    Sundaresh, Aishwarya; Williams, Owen

    2017-01-01

    The t(12;21)(p13;q22) translocation is the most frequently occurring single genetic abnormality in pediatric leukemia. This translocation results in the fusion of the ETV6 and RUNX1 genes. Since its discovery in the 1990s, the function of the ETV6-RUNX1 fusion gene has attracted intense interest. In this chapter, we will summarize current knowledge on the clinical significance of ETV6-RUNX1, the experimental models used to unravel its function in leukemogenesis, the identification of co-operating mutations and the mechanisms responsible for their acquisition, the function of the encoded transcription factor and finally, the future therapeutic approaches available to mitigate the associated disease.

  4. Differential requirement for wild-type Flt3 in leukemia-initiation among mouse models of human leukemia

    PubMed Central

    Kamezaki, Kenjiro; Luchsinger, Larry; Snoeck, Hans-Willem

    2014-01-01

    FLT3 is one of the most frequently mutated genes in acute leukemias. However, the role in leukemogenesis of wt Flt3, which is highly expressed in many hematological malignancies, is unclear. We show here that in mouse models established by retroviral transduction of leukemic fusion proteins deletion of Flt3 strongly inhibits MLL-ENL and to lesser extent p210BCR-ABL-induced leukemogenesis, but has no effect in MLL-AF9 or AML1-ETO9a models. Flt3 acts at the level of leukemic stem cells (LSCs), as a fraction of LSCs in MLL-ENL, but not in MLL-AF9-induced leukemia, expressed Flt3 in vivo, and Flt3 expression on LSCs was associated with leukemia development in this model. Furthermore, efficiency of MLL-ENL, but not of MLL-AF9-induced leukemia induction was significantly enhanced after transduction of Flt3+ compared to Flt3− wt myeloid progenitors. However, Flt3 is not required for immortalization of bone marrow cells in vitro by MLL-ENL and does not affect colony-formation by MLL-ENL LSCs in vitro, suggesting that in vitro models do not reflect the in vivo biology of MLL-ENL leukemia with respect to Flt3 requirement. We conclude that wt Flt3 plays a role in leukemia initiation in vivo, which is, however, not universal. PMID:24269847

  5. Leukemias in Children.

    PubMed

    Seth, Rachna; Singh, Amitabh

    2015-09-01

    Childhood cancers are rare but an important cause of morbidity and mortality in children younger than 15 y of age. Common childhood malignancies include leukemias (commonest, 30-40%), brain tumors (20%) and lymphoma (12%) followed by neuroblastoma, retinoblastoma and tumors arising from soft tissues, bones and gonads. Leukemias, the commonest childhood cancer, arise from clonal proliferation of abnormal hematopoietic cells leading to disruption of normal marrow function and marrow failure. The various clinical manifestations of leukemia result from unregulated proliferation of the malignant clone and bone marrow failure. There are two main subtypes, the commoner, acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). A small proportion may have chronic myeloid leukemia (CML) and juvenile myelomonocytic leukemia (JMML). A systematic approach is necessary for diagnosis. Treatment should be initiated as early as possible to avoid complications. A timely referral to a cancer center must be done if facilities for diagnosis/treatment, management of complications and provision for supportive care are not available at the treating center.

  6. Sorafenib in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia, Acute Lymphoblastic Leukemia, or Chronic Myelogenous Leukemia

    ClinicalTrials.gov

    2013-01-08

    Adult Acute Basophilic Leukemia; Adult Acute Eosinophilic Leukemia; Adult Acute Megakaryoblastic Leukemia (M7); Adult Acute Minimally Differentiated Myeloid Leukemia (M0); 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 Del(5q); 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 Erythroleukemia (M6a); Adult Pure Erythroid Leukemia (M6b); Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia

  7. Laser fusion

    SciTech Connect

    Smit, W.A.; Boskma, P.

    1980-12-01

    Unrestricted laser fusion offers nations an opportunity to circumvent arms control agreements and develop thermonuclear weapons. Early laser weapons research sought a clean radiation-free bomb to replace the fission bomb, but this was deceptive because a fission bomb was needed to trigger the fusion reaction and additional radioactivity was induced by generating fast neutrons. As laser-implosion experiments focused on weapons physics, simulating weapons effects, and applications for new weapons, the military interest shifted from developing a laser-ignited hydrogen bomb to more sophisticated weapons and civilian applications for power generation. Civilian and military research now overlap, making it possible for several countries to continue weapons activities and permitting proliferation of nuclear weapons. These countries are reluctant to include inertial confinement fusion research in the Non-Proliferation Treaty. 16 references. (DCK)

  8. The Antiviral Alkaloid Berberine Reduces Chikungunya Virus-Induced Mitogen-Activated Protein Kinase Signaling.

    PubMed

    Varghese, Finny S; Thaa, Bastian; Amrun, Siti Naqiah; Simarmata, Diane; Rausalu, Kai; Nyman, Tuula A; Merits, Andres; McInerney, Gerald M; Ng, Lisa F P; Ahola, Tero

    2016-11-01

    Chikungunya virus (CHIKV) has infected millions of people in the tropical and subtropical regions since its reemergence in the last decade. We recently identified the nontoxic plant alkaloid berberine as an antiviral substance against CHIKV in a high-throughput screen. Here, we show that berberine is effective in multiple cell types against a variety of CHIKV strains, also at a high multiplicity of infection, consolidating the potential of berberine as an antiviral drug. We excluded any effect of this compound on virus entry or on the activity of the viral replicase. A human phosphokinase array revealed that CHIKV infection specifically activated the major mitogen-activated protein kinase (MAPK) signaling pathways extracellular signal-related kinase (ERK), p38 and c-Jun NH2-terminal kinase (JNK). Upon treatment with berberine, this virus-induced MAPK activation was markedly reduced. Subsequent analyses with specific inhibitors of these kinases indicated that the ERK and JNK signaling cascades are important for the generation of progeny virions. In contrast to specific MAPK inhibitors, berberine lowered virus-induced activation of all major MAPK pathways and resulted in a stronger reduction in viral titers. Further, we assessed the in vivo efficacy of berberine in a mouse model and measured a significant reduction of CHIKV-induced inflammatory disease. In summary, we demonstrate the efficacy of berberine as a drug against CHIKV and highlight the importance of the MAPK signaling pathways in the alphavirus infectious cycle. Chikungunya virus (CHIKV) is a mosquito-borne virus that causes severe and persistent muscle and joint pain and has recently spread to the Americas. No licensed drug exists to counter this virus. In this study, we report that the alkaloid berberine is antiviral against different CHIKV strains and in multiple human cell lines. We demonstrate that berberine collectively reduced the virus-induced activation of cellular mitogen-activated protein kinase

  9. Activation of a promyelocytic leukemia-tumor protein 53 axis underlies acute promyelocytic leukemia cure.

    PubMed

    Ablain, Julien; Rice, Kim; Soilihi, Hassane; de Reynies, Aurélien; Minucci, Saverio; de Thé, Hugues

    2014-02-01

    Acute promyelocytic leukemia (APL) is driven by the promyelocytic leukemia (PML)-retinoic acid receptor-α (PML-RARA) fusion protein, which interferes with nuclear receptor signaling and PML nuclear body (NB) assembly. APL is the only malignancy definitively cured by targeted therapies: retinoic acid (RA) and/or arsenic trioxide, which both trigger PML-RARA degradation through nonoverlapping pathways. Yet, the cellular and molecular determinants of treatment efficacy remain disputed. We demonstrate that a functional Pml-transformation-related protein 53 (Trp53) axis is required to eradicate leukemia-initiating cells in a mouse model of APL. Upon RA-induced PML-RARA degradation, normal Pml elicits NB reformation and induces a Trp53 response exhibiting features of senescence but not apoptosis, ultimately abrogating APL-initiating activity. Apart from triggering PML-RARA degradation, arsenic trioxide also targets normal PML to enhance NB reformation, which may explain its clinical potency, alone or with RA. This Pml-Trp53 checkpoint initiated by therapy-triggered NB restoration is specific for PML-RARA-driven APL, but not the RA-resistant promyelocytic leukemia zinc finger (PLZF)-RARA variant. Yet, as NB biogenesis is druggable, it could be therapeutically exploited in non-APL malignancies.

  10. Proteasome inhibitor MG-132 enhances histone deacetylase inhibitor SAHA-induced cell death of chronic myeloid leukemia cells by an ROS-mediated mechanism and downregulation of the Bcr-Abl fusion protein

    PubMed Central

    ZHOU, WENJING; ZHU, WEIWEI; MA, LIYA; XIAO, FENG; QIAN, WENBIN

    2015-01-01

    Recently, there has been progress in the treatment of chronic myeloid leukemia (CML). However, novel therapeutic strategies are required in order to address the emerging problem of imatinib resistance. Histone deacetylase inhibitors (HDACi) and proteasome inhibitors are promising alternatives, and may be amenable to integration with current therapeutic approaches. However, the mechanisms underlying the interaction between these two agents remain unclear. The present study assessed the cytotoxic effect of the HDACi, suberoylanilide hydroxamic acid (SAHA), in combination with the proteasome inhibitor, MG-132, in imatinib-sensitive K562 and imatinib-resistant K562G cells, and investigated the mechanism underlying this effect. Cell viability was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method and protein expression levels were determined by western blotting. Reactive oxygen species (ROS) generation levels were observed under a fluorescence microscope The results indicated that SAHA and MG-132 act in a synergistic manner to induce cell death in K562 and K562G cells. This effect was associated with Bcr-Abl downregulation and the production of ROS. Notably, the ROS scavenger, N-acetyl-L-cysteine, almost fully reversed the cell death and Bcr-Abl downregulation that was induced by the combination of SAHA and MG-132. By contrast, the pan-caspase inhibitor, z-VAD-fmk, only partially reversed the cell death induced by these two drugs in CML cells. These results indicated that increased intracellular ROS levels are important in the induction of cell death and the downregulation of Bcr-Abl. In conclusion, the present results suggested that combined SAHA and MG-132 may be a promising treatment for CML. PMID:26722260

  11. Dermatoglyphics in childhood leukemia

    PubMed Central

    Berka, Ludmila; McClure, P. D.; Sonley, Marilyn J.; Thompson, Margaret W.

    1971-01-01

    The dermatoglyphics of 54 leukemic children do not differ significantly from those of 25 mothers and 592 unrelated controls with respect to frequency of digital pattern types, position of axial triradius, or type of palmar flexion creases. These findings do not support the hypothesis that children with leukemia have an increased frequency of unusual dermal patterns, but suggest that the dermatoglyphics of leukemic children are not distinctive and therefore have no practical value in the diagnosis of childhood leukemia. Whatever factors are responsible for the development of leukemia in children, these factors do not appear regularly to affect the differentiation of the dermal ridges. PMID:5112119

  12. PU.1-mediated upregulation of M-CSFR is critical for MOZ-leukemia stem cell potential

    PubMed Central

    Aikawa, Yukiko; Katsumoto, Takuo; Zhang, Pu; Shima, Haruko; Shino, Mika; Terui, Kiminori; Ito, Etsuro; Ohno, Hiroaki; Stanley, E. Richard; Singh, Harinder; Tenen, Daniel G; Kitabayashi, Issay

    2011-01-01

    Leukemias and other cancers possess self-renewing stem cells that help to maintain the cancer1,2. Cancer stem cell eradication is thought to be critical for successful anti-cancer therapy. Using an acute myeloid leukemia (AML) model induced by introducing the leukemia-associated monocytic leukemia zinc finger (MOZ)-TIF2 fusion protein, we show here that AML can be cured by the ablation of leukemia stem cells. The MOZ-fusion proteins interacted with PU.1 to stimulate the expression of macrophage-colony stimulating factor receptor (M-CSFR, also called CSF1R/c-FMS/CD115). Analysis using PU.1-deficient mice demonstrated that PU.1 was essential for MOZ-TIF2 to establish and maintain AML stem cells. Cells expressing high levels of CSF1R (CSF1Rhigh cells), but not those expressing low levels of CSF1R (CSF1Rlow/− cells), showed potent leukemia-initiating activity. Using transgenic mice expressing a drug-inducible suicide gene controlled by the CSF1R promoter, AML was cured by ablation of the CSF1Rhigh cells. Induction of AML was suppressed in CSF1R-deficient mice. CSF1R inhibitors slowed the progress of MOZ-TIF2–induced leukemia. Thus, CSF1Rhigh cells contain leukemia stem cells, and the PU.1-mediated upregulation of CSF1R may be a useful therapeutic target for MOZ leukemia. PMID:20418886

  13. An immunoreceptor tyrosine activation motif in the mouse mammary tumor virus envelope protein plays a role in virus-induced mammary tumors.

    PubMed

    Ross, Susan R; Schmidt, John W; Katz, Elad; Cappelli, Laura; Hultine, Stacy; Gimotty, Phyllis; Monroe, John G

    2006-09-01

    Mouse mammary tumor virus (MMTV) induces breast cancer with almost 100% efficiency in susceptible strains through insertional activation of protooncogenes, such as members of the wnt and fibroblast growth factor (fgf) families. We previously showed that expression of the MMTV envelope protein (Env) in normal immortalized mammary epithelial cells grown in three-dimensional cultures caused their morphological transformation, and that this phenotype depended on an immunoreceptor tyrosine-based activation motif (ITAM) present in Env and signaling through the Syk tyrosine kinase (E. Katz, M. H. Lareef, J. C. Rassa, S. M. Grande, L. B. King, J. Russo, S. R. Ross, and J. G. Monroe, J. Exp. Med. 201:431-439, 2005). Here, we examined the role of the Env protein in virus-induced mammary tumorigenesis in vivo. Similar to the effect seen in vitro, Env expression in the mammary glands of transgenic mice bearing either full-length wild-type provirus or only Env transgenes showed increased lobuloalveolar budding. Introduction of the ITAM mutation into the env of an infectious, replication-competent MMTV or into MMTV/murine leukemia virus pseudotypes had no effect on incorporation of Env into virus particles or on in vitro infectivity. Moreover, replication-competent MMTV bearing the ITAM mutation in Env infected lymphoid and mammary tissue at the same level as wild-type MMTV and was transmitted through milk. However, mammary tumor induction was greatly attenuated, and the pattern of oncogene activation was altered. Taken together, these studies indicate that the MMTV Env protein participates in mammary epithelial cell transformation in vivo and that this requires a functional ITAM in the envelope protein.

  14. Acute Myeloid Leukemia (AML) (For Parents)

    MedlinePlus

    ... TV, Video Games, and the Internet Acute Myeloid Leukemia (AML) KidsHealth > For Parents > Acute Myeloid Leukemia (AML) ... Treatment Coping en español Leucemia mieloide aguda About Leukemia Leukemia is a type of cancer that affects ...

  15. Can Acute Myeloid Leukemia Be Prevented?

    MedlinePlus

    ... Causes, Risk Factors, and Prevention Can Acute Myeloid Leukemia Be Prevented? It’s not clear what causes most ... Myeloid Leukemia Be Prevented? More In Acute Myeloid Leukemia About Acute Myeloid Leukemia Causes, Risk Factors, and ...

  16. Preclinical modeling of cytosine arabinoside response in Mll-Enl translocator mouse leukemias.

    PubMed

    Cano, Florencia; Pannel, Richard; Follows, George A; Rabbitts, Terence H

    2008-03-01

    Mouse models of human cancer are a potential preclinical setting for drug testing and for development of methods for delivery of macromolecular drugs to tumors. We have assessed a mouse model of leukemia caused by Mll-Enl protein fusion as a preclinical situation in which myeloid-lineage leukemia results from de novo occurrence of chromosomal translocations between Mll and Enl genes. Here, we show that the mouse leukemias respond to cytosine arabinoside, a frontline treatment for human leukemia. The observations show that the myeloid cells are susceptible to the drug and the mice undergo a remission that comprises a reduction of the myeloid population of cells and recovery of the lymphoid population. This translocator model should therefore prove useful for future drug assessments against the recurrent mixed-lineage leukemia-associated translocations.

  17. Recognition of viral antigens in 6/94 virus-induced T-cell-mediated cytotoxicity.

    PubMed

    Pickel, K; Solvay, M J

    1979-01-24

    Distinct events in the virus-stimulated T-cell-mediated cytotoxicity (V-CMC) have been investigated: 1.) The induction of V-CMC is possible by immunizing mice with infectious as well as UV-inactivated virus (parainfluenza type 1 strain 6/94), or with virus-infected cells either compatible or imcompatible with the recipient. 2). Recognition of viral antigens by the effector cells occurs independently of the H2 environment: Fractionation of effector cells on columns loaded with virus-infected cells eliminates virus-specific cytotoxic cells. Effector cells and cells on the column need not share H-2 antigens. The findings are discussed with regard to the H2 restriction of the virus induced T-cells mediated cytotoxicity.

  18. A virus-induced gene silencing method to study soybean cyst nematode parasitism in Glycine max

    PubMed Central

    2013-01-01

    Background Bean pod mottle virus (BPMV) based virus-induced gene silencing (VIGS) vectors have been developed and used in soybean for the functional analysis of genes involved in disease resistance to foliar pathogens. However, BPMV-VIGS protocols for studying genes involved in disease resistance or symbiotic associations with root microbes have not been developed. Findings Here we describe a BPMV-VIGS protocol suitable for reverse genetic studies in soybean roots. We use this method for analyzing soybean genes involved in resistance to soybean cyst nematode (SCN). A detailed SCN screening pipeline is described. Conclusions The VIGS method described here provides a new tool to identify genes involved in soybean-nematode interactions. This method could be adapted to study genes associated with any root pathogenic or symbiotic associations. PMID:23830484

  19. The methyltransferase Setdb2 mediates virus-induced susceptibility to bacterial superinfection

    PubMed Central

    Schliehe, Christopher; Swaminanthan, Savitha; Bosnjak, Berislav; Bauer, Lisa; Kandasamy, Richard K.; Griesshammer, Isabel M.; Kosack, Lindsay; Schmitz, Frank; Litvak, Vladimir; Sissons, James; Lercher, Alexander; Bhattacharya, Anannya; Khamina, Kseniya; Trivett, Anna L.; Tessarollo, Lino; Mesteri, Ildiko; Hladik, Anastasiya; Merkler, Doron; Kubicek, Stefan; Knapp, Sylvia; Epstein, Michelle M.; Bergthaler, Andreas

    2014-01-01

    Immune responses are tightly regulated to ensure efficient pathogen clearance while avoiding tissue damage. Here we report that SET domain bifurcated 2 (Setdb2) was the only protein lysine methyltransferase induced during influenza virus infection. Setdb2 expression depended on type-I interferon signaling and it repressed the expression of the neutrophil attractant Cxcl1 and other NF-κB target genes. This coincided with Setdb2 occupancy at the Cxcl1 promoter, which in the absence of Setdb2 displayed reduced H3K9 tri-methylation. Setdb2 hypomorphic gene-trap mice exhibited increased neutrophil infiltration in sterile lung inflammation and were less sensitive to bacterial superinfection upon influenza virus infection. This suggests that a Setdb2-mediated regulatory crosstalk between the type-I interferon and NF-κB pathways represents an important mechanism for virus-induced susceptibility to bacterial superinfection. PMID:25419628

  20. Epithelial-mesenchymal transition: molecular pathways of hepatitis viruses-induced hepatocellular carcinoma progression.

    PubMed

    Panebianco, Concetta; Saracino, Chiara; Pazienza, Valerio

    2014-08-01

    Hepatocellular carcinoma is the fifth most common tumor and the third cause of death for cancer in the world. Among the main causative agents of this tumor is the chronic infection by hepatitis viruses B and C, which establish a context of chronic inflammation degenerating in fibrosis, cirrhosis, and, finally, cancer. Recent findings, however, indicate that hepatitis viruses are not only responsible for cancer onset but also for its progression towards metastasis. Indeed, they are able to promote epithelial-mesenchymal transition, a process of cellular reprogramming underlying tumor spread. In this manuscript, we review the currently known molecular mechanisms by which hepatitis viruses induce epithelial-mesenchymal transition and, thus, hepatocellular carcinoma progression.

  1. Strategies for altering plant traits using virus-induced gene silencing technologies.

    PubMed

    Lacomme, Christophe

    2015-01-01

    The rapid progress in genome sequencing and transcriptome analysis in model and crop plants has made possible the identification of a vast number of genes potentially associated with economically important complex traits. The ultimate goal is to assign functions to these genes by using forward and reverse genetic screens. Plant viruses have been developed for virus-induced gene silencing (VIGS) to generate rapid gene knockdown phenotypes in numerous plant species. To fulfill its potential for high-throughput phenomics, it is of prime importance to ensure that parameters conditioning the VIGS response, i.e., plant-virus interactions and associated loss-of-function screens, are "fit for purpose" and optimized to unequivocally conclude the role of a gene of interest in relation to a given trait. This chapter will review and discuss the different strategies used for the development of VIGS-based phenomics in model and crop species.

  2. Sequence of protein synthesis in cells infected by human cytomegalovirus: early and late virus-induced polypeptides.

    PubMed Central

    Stinski, M F

    1978-01-01

    At least 10 distinct early virus-induced polypeptides were synthesized within 0 to 6 h after infection of permissive cells with cytomegalovirus. These virus-induced polypeptides were synthesized before and independently of viral DNA replication. A majority of these early virus-induced polypeptides were also synthesized in nonpermissive cells, which do not permit viral DNA replication. The virus-induced polypeptides synthesized before viral DNA replication were hypothesized to be nonstructural proteins coded for by the cytomegalovirus genome. Their synthesis was found to be a sequential process, since three proteins preceded the synthesis of the others. Synthesis of all early cytomegalovirus-induced proteins was a transient process; the proteins reached their highest molar ratios before the onset of viral DNA replication. Late viral proteins were synthesized at the time of the onset of viral DNA replication, which was approximately 15 h after infection. Their synthesis was continuous and increased in molar ratios with the accumulation of newly synthesized viral DNA in the cells. The presence of the amino acid analog canavanine or azetadine during the early stage of infection suppressed viral DNA replication. The amount of viral DNA synthesis was directly correlated to the relative amount of late viral protein synthesis. Because synthesis of late viral proteins depended upon viral DNA replication, the proteins were not detected in permissive cells treated with an inhibitor of viral DNA synthesis or in nonpermissive cells that are restrictive for cytomegalovirus DNA replication. Images PMID:209215

  3. Virus-induced gene silencing and transient gene expression in soybean using Bean pod mottle virus infectious clones

    USDA-ARS?s Scientific Manuscript database

    Virus-induced gene silencing (VIGS) is a powerful and rapid approach for determining the functions of plant genes. The basis of VIGS is that a viral genome is engineered so that it can carry fragments of plant genes, typically in the 200-300 base pair size range. The recombinant viruses are used to ...

  4. Virus-induced gene silencing of RPC5-like subunit of RNA polymerase III caused pleiotropic effects in Nicotiana benthamiana

    USDA-ARS?s Scientific Manuscript database

    In eukaryotic cells, RNA polymerase III is highly conserved, contains 17 subunits and transcribes housekeeping genes such as ribosomal 50S rRNA, tRNA and other small RNAs. Functional roles of the RPC5 are poorly characterized in the literature. In this work, we report that virus-induced gene silenci...

  5. Evaluating the ability of the barley stripe mosaic virus-induced gene silencing system to simultaneously silence two wheat genes

    USDA-ARS?s Scientific Manuscript database

    Virus-induced gene silencing (VIGS) is an important tool for rapid assessment of gene function in plants. The ability of the Barley Stripe Mosaic Virus (BSMV) VIGS system to simultaneously silence two genes was assessed by comparing the extent of down-regulation of the wheat PDS and SGT1 genes afte...

  6. Evaluating the Ability of the Barley Stripe Mosaic Virus-Induced Gene Silencing System to Simultaneously Silence Two Wheat Genes

    USDA-ARS?s Scientific Manuscript database

    Virus-induced gene silencing (VIGS) is an important tool for rapid assessment of gene function in plants. The ability of the Barley stripe mosaic virus (BSMV) VIGS system to simultaneously silence two genes was assessed by comparing the extent of down-regulation of the wheat PDS and SGT1 genes afte...

  7. Virus-induced gene silencing in diverse maize lines using the Brome Mosaic virus-based silencing vector

    USDA-ARS?s Scientific Manuscript database

    Virus-induced gene silencing (VIGS) is a widely used tool for gene function studies in many plant species, though its use in monocots has been limited. Using a Brome mosaic virus (BMV) vector designed to silence the maize phytoene desaturase gene, a genetically diverse set of maize inbred lines was ...

  8. Transcriptome analyses and virus induced gene silencing identify genes in the Rpp4-mediated Asian soybean rust resistance pathway

    USDA-ARS?s Scientific Manuscript database

    Rpp4 (Resistance to Phakopsora pachyrhizi 4) confers resistance to P. pachyrhizi, the causal agent of Asian soybean rust (ASR). By combining expression profiling and virus induced gene silencing (VIGS), we are developing a genetic framework for Rpp4-mediated resistance. We measured gene expression i...

  9. An AF9/ENL-targted peptide with therapeutic potential in mixed lineage leukemias.

    PubMed

    Barretto, Nisha N; Karahalios, Dean S; You, Dewen; Hemenway, Charles S

    2014-01-01

    Misregulation of transcription elongation is proposed to underlie the pathobiology of MLL leukemia. AF4, AF9, and ENL, common MLL fusion partners, are found in complex with positive transcription elongation factor b (P-TEFb). AF9 and its homolog ENL directly interact with AF4 within these complexes. Previously, we designed a peptide that mimics the AF9 binding domain of AF4 and reported that MLL leukemia cell lines are inhibited by it. Extending these studies, we have modified the peptide design in order to avoid recognition by proteases. The peptide is as effective as its predecessor in vitro and enhances survival in mice bearing MLL leukemia cell lines.

  10. Interleukin-1β Mediates Virus-Induced M2 Muscarinic Receptor Dysfunction and Airway Hyperreactivity

    PubMed Central

    Rynko, Abby E.; Fryer, Allison D.

    2014-01-01

    Respiratory viral infections are associated with the majority of asthma attacks. Inhibitory M2 receptors on parasympathetic nerves, which normally limit acetylcholine (ACh) release, are dysfunctional after respiratory viral infection. Because IL-1β is up-regulated during respiratory viral infections, we investigated whether IL-1β mediates M2 receptor dysfunction during parainfluenza virus infection. Virus-infected guinea pigs were pretreated with the IL-1β antagonist anakinra. In the absence of anakinra, viral infection increased bronchoconstriction in response to vagal stimulation but not to intravenous ACh, and neuronal M2 muscarinic receptors were dysfunctional. Pretreatment with anakinra prevented virus-induced increased bronchoconstriction and M2 receptor dysfunction. Anakinra did not change smooth muscle M3 muscarinic receptor response to ACh, lung viral loads, or blood and bronchoalveolar lavage leukocyte populations. Respiratory virus infection decreased M2 receptor mRNA expression in parasympathetic ganglia extracted from infected animals, and this was prevented by blocking IL-1β or TNF-α. Treatment of SK-N-SH neuroblastoma cells or primary cultures of guinea pig parasympathetic neurons with IL-1β directly decreased M2 receptor mRNA, and this was not synergistic with TNF-α treatment. Treating guinea pig trachea segment with TNF-α or IL-1β in vitro increased tracheal contractions in response to activation of airway nerves by electrical field stimulation. Blocking IL-1β during TNF-α treatment prevented this hyperresponsiveness. These data show that virus-induced hyperreactivity and M2 dysfunction involves IL-1β and TNF-α, likely in sequence with TNF-α causing production of IL-1β. PMID:24735073

  11. Novel Strategy To Protect against Influenza Virus-Induced Pneumococcal Disease without Interfering with Commensal Colonization

    PubMed Central

    Greene, Christopher J.; Marks, Laura R.; Hu, John C.; Reddinger, Ryan; Mandell, Lorrie; Roche-Hakansson, Hazeline; King-Lyons, Natalie D.

    2016-01-01

    Streptococcus pneumoniae commonly inhabits the nasopharynx as a member of the commensal biofilm. Infection with respiratory viruses, such as influenza A virus, induces commensal S. pneumoniae to disseminate beyond the nasopharynx and to elicit severe infections of the middle ears, lungs, and blood that are associated with high rates of morbidity and mortality. Current preventive strategies, including the polysaccharide conjugate vaccines, aim to eliminate asymptomatic carriage with vaccine-type pneumococci. However, this has resulted in serotype replacement with, so far, less fit pneumococcal strains, which has changed the nasopharyngeal flora, opening the niche for entry of other virulent pathogens (e.g., Streptococcus pyogenes, Staphylococcus aureus, and potentially Haemophilus influenzae). The long-term effects of these changes are unknown. Here, we present an attractive, alternative preventive approach where we subvert virus-induced pneumococcal disease without interfering with commensal colonization, thus specifically targeting disease-causing organisms. In that regard, pneumococcal surface protein A (PspA), a major surface protein of pneumococci, is a promising vaccine target. Intradermal (i.d.) immunization of mice with recombinant PspA in combination with LT-IIb(T13I), a novel i.d. adjuvant of the type II heat-labile enterotoxin family, elicited strong systemic PspA-specific IgG responses without inducing mucosal anti-PspA IgA responses. This response protected mice from otitis media, pneumonia, and septicemia and averted the cytokine storm associated with septic infection but had no effect on asymptomatic colonization. Our results firmly demonstrated that this immunization strategy against virally induced pneumococcal disease can be conferred without disturbing the desirable preexisting commensal colonization of the nasopharynx. PMID:27001538

  12. Pleiotropic Effects of Levofloxacin, Fluoroquinolone Antibiotics, against Influenza Virus-Induced Lung Injury.

    PubMed

    Enoki, Yuki; Ishima, Yu; Tanaka, Ryota; Sato, Keizo; Kimachi, Kazuhiko; Shirai, Tatsuya; Watanabe, Hiroshi; Chuang, Victor T G; Fujiwara, Yukio; Takeya, Motohiro; Otagiri, Masaki; Maruyama, Toru

    2015-01-01

    Reactive oxygen species (ROS) and nitric oxide (NO) are major pathogenic molecules produced during viral lung infections, including influenza. While fluoroquinolones are widely used as antimicrobial agents for treating a variety of bacterial infections, including secondary infections associated with the influenza virus, it has been reported that they also function as anti-oxidants against ROS and as a NO regulator. Therefore, we hypothesized that levofloxacin (LVFX), one of the most frequently used fluoroquinolone derivatives, may attenuate pulmonary injuries associated with influenza virus infections by inhibiting the production of ROS species such as hydroxyl radicals and neutrophil-derived NO that is produced during an influenza viral infection. The therapeutic impact of LVFX was examined in a PR8 (H1N1) influenza virus-induced lung injury mouse model. ESR spin-trapping experiments indicated that LVFX showed scavenging activity against neutrophil-derived hydroxyl radicals. LVFX markedly improved the survival rate of mice that were infected with the influenza virus in a dose-dependent manner. In addition, the LVFX treatment resulted in a dose-dependent decrease in the level of 8-hydroxy-2'-deoxyguanosine (a marker of oxidative stress) and nitrotyrosine (a nitrative marker) in the lungs of virus-infected mice, and the nitrite/nitrate ratio (NO metabolites) and IFN-γ in BALF. These results indicate that LVFX may be of substantial benefit in the treatment of various acute inflammatory disorders such as influenza virus-induced pneumonia, by inhibiting inflammatory cell responses and suppressing the overproduction of NO in the lungs.

  13. Drugs Approved for Leukemia

    Cancer.gov

    This page lists cancer drugs approved by the FDA for use in leukemia. The drug names link to NCI's Cancer Drug Information summaries. The list includes generic names, brand names, and common drug combinations, which are shown in capital letters.

  14. Clonal evolution in leukemia.

    PubMed

    Ferrando, Adolfo A; López-Otín, Carlos

    2017-10-06

    Human leukemias are liquid malignancies characterized by diffuse infiltration of the bone marrow by transformed hematopoietic progenitors. The accessibility of tumor cells obtained from peripheral blood or through bone marrow aspirates, together with recent advances in cancer genomics and single-cell molecular analysis, have facilitated the study of clonal populations and their genetic and epigenetic evolution over time with unprecedented detail. The results of these analyses challenge the classic view of leukemia as a clonal homogeneous diffuse tumor and introduce a more complex and dynamic scenario. In this review, we present current concepts on the role of clonal evolution in lymphoid and myeloid leukemia as a driver of tumor initiation, disease progression and relapse. We also discuss the implications of these concepts in our understanding of the evolutionary mechanisms involved in leukemia transformation and therapy resistance.

  15. Mechanisms of pathogenesis induced by bovine leukemia virus as a model for human T-cell leukemia virus

    PubMed Central

    Aida, Yoko; Murakami, Hironobu; Takahashi, Masahiko; Takeshima, Shin-Nosuke

    2013-01-01

    Bovine leukemia virus (BLV) and human T-cell leukemia virus type 1 (HTLV-1) make up a unique retrovirus family. Both viruses induce chronic lymphoproliferative diseases with BLV affecting the B-cell lineage and HTLV-1 affecting the T-cell lineage. The pathologies of BLV- and HTLV-induced infections are notably similar, with an absence of chronic viraemia and a long latency period. These viruses encode at least two regulatory proteins, namely, Tax and Rex, in the pX region located between the env gene and the 3′ long terminal repeat. The Tax protein is a key contributor to the oncogenic potential of the virus, and is also the key protein involved in viral replication. However, BLV infection is not sufficient for leukemogenesis, and additional events such as gene mutations must take place. In this review, we first summarize the similarities between the two viruses in terms of genomic organization, virology, and pathology. We then describe the current knowledge of the BLV model, which may also be relevant for the understanding of leukemogenesis caused by HTLV-1. In addition, we address our improved understanding of Tax functions through the newly identified BLV Tax mutants, which have a substitution between amino acids 240 and 265. PMID:24265629

  16. Pharmacologic inhibition of the menin-MLL interaction blocks progression of MLL leukemia in vivo

    DOE PAGES

    Borkin, Dmitry; He, Shihan; Miao, Hongzhi; ...

    2015-03-26

    Chromosomal translocations affecting mixed lineage leukemia gene (MLL) result in acute leukemias resistant to therapy. The leukemogenic activity of MLL fusion proteins is dependent on their interaction with menin, providing basis for therapeutic intervention. In this paper, we report the development of highly potent and orally bioavailable small-molecule inhibitors of the menin-MLL interaction, MI-463 and MI-503, and show their profound effects in MLL leukemia cells and substantial survival benefit in mouse models of MLL leukemia. Finally, we demonstrate the efficacy of these compounds in primary samples derived from MLL leukemia patients. In conclusion, overall, we demonstrate that pharmacologic inhibition ofmore » the menin-MLL interaction represents an effective treatment for MLL leukemias in vivo and provide advanced molecular scaffold for clinical lead identification.« less

  17. Aberrant expression of CKLF-like MARVEL transmembrane member 5 (CMTM5) by promoter methylation in myeloid leukemia.

    PubMed

    Niu, Jihong; Li, Henan; Zhang, Yao; Li, Jinlan; Xie, Min; Li, Lingdi; Qin, Xiaoying; Qin, Yazhen; Guo, Xiaohuan; Jiang, Qian; Liu, Yanrong; Chen, Shanshan; Huang, Xiaojun; Han, Wenling; Ruan, Guorui

    2011-06-01

    CMTM5 has been shown to exhibit tumor suppressor activities, however, its role in leukemia is unclear. Herein we firstly reported the expression and function of CMTM5 in myeloid leukemia. CMTM5 was down-regulated, or undetectable, in leukemia cell lines and bone marrow cells from leukemia patients with promoter methylation. Ectopic expression of CMTM5-v1 strongly inhibited the proliferation of K562 and MEG-01 cells. In addition, significant negative correlations were observed between CMTM5 and three leukemia-specific fusion genes (AML1-ETO, PML-RARα and BCR/ABL1). CMTM5 expression was up-regulated in patients who had undergone treatment. Therefore, CMTM5 may be involved in the pathomechanism of myeloid leukemias. Copyright © 2010 Elsevier Ltd. All rights reserved.

  18. CT findings in leukemia

    SciTech Connect

    Heiberg, E.; Wolverson, M.K.; Sundaram, M.; Shields, J.B.

    1984-12-01

    Review of 84 computed tomographic (CT) scans in leukemic patients demonstrate a wide spectrum of abnormalities. Findings caused by leukemia were lymphadenopathy, visceral enlargement, focal defects, and tissue infiltration. Hemorrhage was by far the most common complication and could usually be characterized on the noncontrast CT scan. The distinction between old hematomas, foci of infection, and leukemia infiltration could not be made with certainty without CT-guided aspiration. Unusual instances of sepsis, such as microabscesses of the liver and typhlitis, were seen.

  19. Treatment of Children with APL (Acute Promyelocytic Leukemia)

    MedlinePlus

    ... Childhood Leukemia Treatment of Children With Acute Promyelocytic Leukemia (APL) Treatment of acute promyelocytic leukemia (APL), the ... With Chronic Myelogenous Leukemia (CML) More In Childhood Leukemia About Childhood Leukemia Causes, Risk Factors, and Prevention ...

  20. Treatment of Chronic Lymphocytic Leukemia by Risk Group

    MedlinePlus

    ... Chronic Lymphocytic Leukemia Typical Treatment of Chronic Lymphocytic Leukemia Treatment options for chronic lymphocytic leukemia (CLL) vary ... Treating Hairy Cell Leukemia More In Chronic Lymphocytic Leukemia About Chronic Lymphocytic Leukemia Causes, Risk Factors, and ...

  1. Tipifarnib and Bortezomib in Treating Patients With Acute Leukemia or Chronic Myelogenous Leukemia in Blast Phase

    ClinicalTrials.gov

    2015-04-14

    Adult Acute Basophilic Leukemia; Adult Acute Eosinophilic Leukemia; 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; Blastic Phase; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Recurrent Disease; Untreated Adult Acute Lymphoblastic Leukemia; Untreated Adult Acute Myeloid Leukemia

  2. BMS-214662 in Treating Patients With Acute Leukemia, Myelodysplastic Syndrome, or Chronic Myeloid Leukemia

    ClinicalTrials.gov

    2013-01-22

    Adult Acute Promyelocytic Leukemia (M3); Blastic Phase Chronic Myelogenous Leukemia; Childhood Myelodysplastic Syndromes; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Acute Myeloid Leukemia; Refractory Anemia With Excess Blasts; Refractory Anemia With Excess Blasts in Transformation; Relapsing Chronic Myelogenous Leukemia

  3. Flavopiridol and Vorinostat in Treating Patients With Relapsed or Refractory Acute Leukemia or Chronic Myelogenous Leukemia or Refractory Anemia

    ClinicalTrials.gov

    2013-04-01

    Blastic Phase Chronic Myelogenous Leukemia; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Refractory Anemia With Excess Blasts; Relapsing Chronic Myelogenous Leukemia; Untreated Adult Acute Lymphoblastic Leukemia; Untreated Adult Acute Myeloid Leukemia

  4. Clathrin assembly lymphoid myeloid leukemia-AF10-positive acute leukemias: a report of 2 cases with a review of the literature.

    PubMed

    Huh, Ji Young; Chung, Soie; Oh, Doyeun; Kang, Myung Seo; Eom, Hyeon Seok; Cho, Eun Hae; Han, Mi Hwa; Kong, Sun Young

    2010-04-01

    The translocation t(10;11)(p13;q14q21) has been found to be recurrent in acute lymphoblastic and myeloid leukemias, and results in the fusion of the clathrin assembly lymphoid myeloid leukemia (CALM) gene with the AF10 gene; these genes are present on chromosomes 11 and 10, respectively. Because the CALM-AF10 rearrangement is a rare chromosomal abnormality, it is not included in routine molecular tests for acute leukemia. Here, we describe the cases of 2 patients with the CALM-AF10 fusion gene. The first patient (case 1) was diagnosed with T-cell ALL, and the second patient (case 2) was diagnosed with AML. Both patient samples showed expression of the homeobox A gene cluster and the histone methyltransferase hDOT1L, which suggests that they mediate leukemic transformation in CALM-AF10-positive and mixed-lineage leukemia-AF10-positive leukemias. Both patients achieved complete remission after induction chemotherapy. The first patient (case 1) relapsed after double-unit cord blood transplantation; there was no evidence of relapse in the second patient (case 2) after allogenic peripheral blood stem cell transplantation. Since CALM-AF10- positive leukemias have been shown to have poor prognosis with conventional therapy, molecular tests for CALM-AF10 rearrangement would be necessary to detect minimal residual disease during follow-up.

  5. Cold fusion, Alchemist's dream

    SciTech Connect

    Clayton, E.D.

    1989-09-01

    In this report the following topics relating to cold fusion are discussed: muon catalysed cold fusion; piezonuclear fusion; sundry explanations pertaining to cold fusion; cosmic ray muon catalysed cold fusion; vibrational mechanisms in excited states of D{sub 2} molecules; barrier penetration probabilities within the hydrogenated metal lattice/piezonuclear fusion; branching ratios of D{sub 2} fusion at low energies; fusion of deuterons into {sup 4}He; secondary D+T fusion within the hydrogenated metal lattice; {sup 3}He to {sup 4}He ratio within the metal lattice; shock induced fusion; and anomalously high isotopic ratios of {sup 3}He/{sup 4}He.

  6. Anticipation in familial leukemia

    SciTech Connect

    Horwitz, M.; Jarvik, G.P.; Goode, E.L.

    1996-11-01

    Anticipation refers to worsening severity or earlier age at onset with each generation for an inherited disease and primarily has been described for neurodegenerative illnesses resulting from expansion of trinucleotide repeats. We have tested for evidence of anticipation in familial leukemia. Of 49 affected individuals in nine families transmitting autosomal dominant acute myelogenous leukemia (AML), the mean age at onset is 57 years in the grandparental generation, 32 years in the parental generation, and 13 years in the youngest generation (P < .001). Of 21 parent-child pairs with AML, 19 show younger ages at onset in the child and demonstrate a mean decline in age at onset of 28 years (P < .001). Of 18 affected individuals from seven pedigrees with autosomal dominant chronic lymphocytic leukemia (CLL), the mean age at onset in the parental generation is 66 years versus 51 years in the youngest generation (P = .008). Of nine parent-child pairs with CLL, eight show younger ages at onset in the child and reveal a mean decline in age at onset of 21 years (P = .001). Inspection of rare pedigrees transmitting acute lymphocytic leukemia, chronic myelogenous leukemia, multiple types of leukemia, and lymphoma is also compatible with anticipation. Sampling bias is unlikely to explain these findings. This suggests that dynamic mutation of unstable DNA sequence repeats could be a common mechanism of inherited hematopoietic malignancy with implications for the role of somatic mutation in the more frequent sporadic cases. We speculate on three possible candidate genes for familial leukemia with anticipation: a locus on 21q22.1-22.2, CBL2 on 11q23.3, and CBFB or a nearby gene on 16q22. 55 refs., 4 figs.

  7. The MLL recombinome of acute leukemias in 2013

    PubMed Central

    Meyer, C; Hofmann, J; Burmeister, T; Gröger, D; Park, T S; Emerenciano, M; Pombo de Oliveira, M; Renneville, A; Villarese, P; Macintyre, E; Cavé, H; Clappier, E; Mass-Malo, K; Zuna, J; Trka, J; De Braekeleer, E; De Braekeleer, M; Oh, S H; Tsaur, G; Fechina, L; van der Velden, V H J; van Dongen, J J M; Delabesse, E; Binato, R; Silva, M L M; Kustanovich, A; Aleinikova, O; Harris, M H; Lund-Aho, T; Juvonen, V; Heidenreich, O; Vormoor, J; Choi, W W L; Jarosova, M; Kolenova, A; Bueno, C; Menendez, P; Wehner, S; Eckert, C; Talmant, P; Tondeur, S; Lippert, E; Launay, E; Henry, C; Ballerini, P; Lapillone, H; Callanan, M B; Cayuela, J M; Herbaux, C; Cazzaniga, G; Kakadiya, P M; Bohlander, S; Ahlmann, M; Choi, J R; Gameiro, P; Lee, D S; Krauter, J; Cornillet-Lefebvre, P; Te Kronnie, G; Schäfer, B W; Kubetzko, S; Alonso, C N; zur Stadt, U; Sutton, R; Venn, N C; Izraeli, S; Trakhtenbrot, L; Madsen, H O; Archer, P; Hancock, J; Cerveira, N; Teixeira, M R; Lo Nigro, L; Möricke, A; Stanulla, M; Schrappe, M; Sedék, L; Szczepański, T; Zwaan, C M; Coenen, E A; van den Heuvel-Eibrink, M M; Strehl, S; Dworzak, M; Panzer-Grümayer, R; Dingermann, T; Klingebiel, T; Marschalek, R

    2013-01-01

    Chromosomal rearrangements of the human MLL (mixed lineage leukemia) gene are associated with high-risk infant, pediatric, adult and therapy-induced acute leukemias. We used long-distance inverse-polymerase chain reaction to characterize the chromosomal rearrangement of individual acute leukemia patients. We present data of the molecular characterization of 1590 MLL-rearranged biopsy samples obtained from acute leukemia patients. The precise localization of genomic breakpoints within the MLL gene and the involved translocation partner genes (TPGs) were determined and novel TPGs identified. All patients were classified according to their gender (852 females and 745 males), age at diagnosis (558 infant, 416 pediatric and 616 adult leukemia patients) and other clinical criteria. Combined data of our study and recently published data revealed a total of 121 different MLL rearrangements, of which 79 TPGs are now characterized at the molecular level. However, only seven rearrangements seem to be predominantly associated with illegitimate recombinations of the MLL gene (∼90%): AFF1/AF4, MLLT3/AF9, MLLT1/ENL, MLLT10/AF10, ELL, partial tandem duplications (MLL PTDs) and MLLT4/AF6, respectively. The MLL breakpoint distributions for all clinical relevant subtypes (gender, disease type, age at diagnosis, reciprocal, complex and therapy-induced translocations) are presented. Finally, we present the extending network of reciprocal MLL fusions deriving from complex rearrangements. PMID:23628958

  8. The MLL recombinome of acute leukemias in 2013.

    PubMed

    Meyer, C; Hofmann, J; Burmeister, T; Gröger, D; Park, T S; Emerenciano, M; Pombo de Oliveira, M; Renneville, A; Villarese, P; Macintyre, E; Cavé, H; Clappier, E; Mass-Malo, K; Zuna, J; Trka, J; De Braekeleer, E; De Braekeleer, M; Oh, S H; Tsaur, G; Fechina, L; van der Velden, V H J; van Dongen, J J M; Delabesse, E; Binato, R; Silva, M L M; Kustanovich, A; Aleinikova, O; Harris, M H; Lund-Aho, T; Juvonen, V; Heidenreich, O; Vormoor, J; Choi, W W L; Jarosova, M; Kolenova, A; Bueno, C; Menendez, P; Wehner, S; Eckert, C; Talmant, P; Tondeur, S; Lippert, E; Launay, E; Henry, C; Ballerini, P; Lapillone, H; Callanan, M B; Cayuela, J M; Herbaux, C; Cazzaniga, G; Kakadiya, P M; Bohlander, S; Ahlmann, M; Choi, J R; Gameiro, P; Lee, D S; Krauter, J; Cornillet-Lefebvre, P; Te Kronnie, G; Schäfer, B W; Kubetzko, S; Alonso, C N; zur Stadt, U; Sutton, R; Venn, N C; Izraeli, S; Trakhtenbrot, L; Madsen, H O; Archer, P; Hancock, J; Cerveira, N; Teixeira, M R; Lo Nigro, L; Möricke, A; Stanulla, M; Schrappe, M; Sedék, L; Szczepański, T; Zwaan, C M; Coenen, E A; van den Heuvel-Eibrink, M M; Strehl, S; Dworzak, M; Panzer-Grümayer, R; Dingermann, T; Klingebiel, T; Marschalek, R

    2013-11-01

    Chromosomal rearrangements of the human MLL (mixed lineage leukemia) gene are associated with high-risk infant, pediatric, adult and therapy-induced acute leukemias. We used long-distance inverse-polymerase chain reaction to characterize the chromosomal rearrangement of individual acute leukemia patients. We present data of the molecular characterization of 1590 MLL-rearranged biopsy samples obtained from acute leukemia patients. The precise localization of genomic breakpoints within the MLL gene and the involved translocation partner genes (TPGs) were determined and novel TPGs identified. All patients were classified according to their gender (852 females and 745 males), age at diagnosis (558 infant, 416 pediatric and 616 adult leukemia patients) and other clinical criteria. Combined data of our study and recently published data revealed a total of 121 different MLL rearrangements, of which 79 TPGs are now characterized at the molecular level. However, only seven rearrangements seem to be predominantly associated with illegitimate recombinations of the MLL gene (≈ 90%): AFF1/AF4, MLLT3/AF9, MLLT1/ENL, MLLT10/AF10, ELL, partial tandem duplications (MLL PTDs) and MLLT4/AF6, respectively. The MLL breakpoint distributions for all clinical relevant subtypes (gender, disease type, age at diagnosis, reciprocal, complex and therapy-induced translocations) are presented. Finally, we present the extending network of reciprocal MLL fusions deriving from complex rearrangements.

  9. Topoisomerase II and leukemia

    PubMed Central

    Pendleton, MaryJean; Lindsey, R. Hunter; Felix, Carolyn A.; Grimwade, David; Osheroff, Neil

    2014-01-01

    Type II topoisomerases are essential enzymes that modulate DNA under- and overwinding, knotting, and tangling. Beyond their critical physiological functions, these enzymes are the targets for some of the most widely prescribed anticancer drugs (topoisomerase II poisons) in clinical use. Topoisomerase II poisons kill cells by increasing levels of covalent enzyme-cleaved DNA complexes that are normal reaction intermediates. Drugs such as etoposide, doxorubicin, and mitoxantrone are frontline therapies for a variety of solid tumors and hematological malignancies. Unfortunately, their use is also associated with the development of specific leukemias. Regimens that include etoposide or doxorubicin are linked to the occurrence of acute myeloid leukemias that feature rearrangements at chromosomal band 11q23. Similar rearrangements are seen in infant leukemias and are associated with gestational diets that are high in naturally occurring topoisomerase II–active compounds. Finally, regimens that include mitoxantrone and epirubicin are linked to acute promyelocytic leukemias that feature t(15;17) rearrangements. The first part of this article will focus on type II topoisomerases and describe the mechanism of enzyme and drug action. The second part will discuss how topoisomerase II poisons trigger chromosomal breaks that lead to leukemia and potential approaches for dissociating the actions of drugs from their leukemogenic potential. PMID:24495080

  10. Obatoclax, Fludarabine, and Rituximab in Treating Patients With Previously Treated Chronic Lymphocytic Leukemia

    ClinicalTrials.gov

    2013-09-27

    B-cell Chronic Lymphocytic Leukemia; Leukemia; Prolymphocytic Leukemia; Refractory Chronic Lymphocytic Leukemia; Stage I Chronic Lymphocytic Leukemia; Stage II Chronic Lymphocytic Leukemia; Stage III Chronic Lymphocytic Leukemia; Stage IV Chronic Lymphocytic Leukemia

  11. Adaptive immunity to leukemia is inhibited by cross-reactive induced regulatory T cells

    PubMed Central

    Manlove, Luke S.; Berquam-Vrieze, Katherine E.; Pauken, Kristen E.; Williams, Richard T.; Jenkins, Marc K.; Farrar, Michael A.

    2015-01-01

    BCR-ABL+ acute lymphoblastic leukemia patients have transient responses to current therapies. However, the fusion of BCR to ABL generates a potential leukemia-specific antigen that could be a target for immunotherapy. We demonstrate that the immune system can limit BCR-ABL+ leukemia progression although ultimately this immune response fails. To address how BCR-ABL+ leukemia escapes immune surveillance, we developed a peptide: MHC-II tetramer that labels endogenous BCR-ABL-specific CD4+ T cells. Naïve mice harbored a small population of BCR-ABL-specific T cells that proliferated modestly upon immunization. The small number of naïve BCR-ABL specific T cells was due to negative selection in the thymus, which depleted BCR-ABL specific T cells. Consistent with this observation, we saw that BCR-ABL specific T cells were cross-reactive with an endogenous peptide derived from ABL. Despite this cross-reactivity, the remaining population of BCR-ABL reactive T cells proliferated upon immunization with the BCR-ABL fusion peptide and adjuvant. In response to BCR-ABL+ leukemia, BCR-ABL specific T cells proliferated and converted into regulatory T cells (Treg cells), a process that was dependent on cross-reactivity with self-antigen, TGFβ1, and MHC-II antigen presentation by leukemic cells. Treg cells were critical for leukemia progression in C57Bl/6 mice, as transient Treg cell ablation led to extended survival of leukemic mice. Thus, BCR-ABL+ leukemia actively suppresses anti-leukemia immune responses by converting cross-reactive leukemia-specific T cells into Treg cells. PMID:26378075

  12. Characterization of the HIV N-terminal fusion peptide-containing region in context of key gp41 fusion conformations.

    PubMed

    Sackett, Kelly; Wexler-Cohen, Yael; Shai, Yechiel

    2006-08-04

    Central to our understanding of human immunodeficiency virus-induced fusion is the high resolution structure of fragments of the gp41 fusion protein folded in a low energy core conformation. However, regions fundamental to fusion, like the fusion peptide (FP), have yet to be characterized in the context of the cognate protein regardless of its conformation. Based on conformation-specific monoclonal antibody recognition, we identified the polar region consecutive to the N36 fragment as a stabilizer of trimeric coiled-coil assembly, thereby enhancing inhibitory potency. This tertiary organization is retained in the context of the hydrophobic FP (N70 fragment). Our data indicate that the N70 fragment recapitulates the expected organization of this region in the viral fusion intermediate (N-terminal half of the pre-hairpin intermediate (N-PHI)), which happens to be the prime target for fusion inhibitors. Regarding the low energy conformation, we show for the first time core formation in the context of the FP (N70 core). The alpha-helical and coiled-coil stabilizing polar region confers substantial thermal stability to the core, whereas the hydrophobic FP does not add further stability. For the two key fusion conformations, N-PHI and N70 core, we find that the FP adopts a nonhelical structure and directs higher order assembly (assembly of coiled coils in N-PHI and assembly of bundles in the N70 core). This supra-molecular organization of coiled coils or folded cores is seen only in the context of the FP. This study is the first to characterize the FP region in the context of the folded core and provides a basic understanding of the role of the elusive FP for key gp41 fusion conformations.

  13. NUP98 gene fusions and hematopoietic malignancies: common themes and new biologic insights

    PubMed Central

    Gough, Sheryl M.; Slape, Christopher I.

    2011-01-01

    Structural chromosomal rearrangements of the Nucleoporin 98 gene (NUP98), primarily balanced translocations and inversions, are associated with a wide array of hematopoietic malignancies. NUP98 is known to be fused to at least 28 different partner genes in patients with hematopoietic malignancies, including acute myeloid leukemia, chronic myeloid leukemia in blast crisis, myelodysplastic syndrome, acute lymphoblastic leukemia, and bilineage/biphenotypic leukemia. NUP98 gene fusions typically encode a fusion protein that retains the amino terminus of NUP98; in this context, it is important to note that several recent studies have demonstrated that the amino-terminal portion of NUP98 exhibits transcription activation potential. Approximately half of the NUP98 fusion partners encode homeodomain proteins, and at least 5 NUP98 fusions involve known histone-modifying genes. Several of the NUP98 fusions, including NUP98-homeobox (HOX)A9, NUP98-HOXD13, and NUP98-JARID1A, have been used to generate animal models of both lymphoid and myeloid malignancy; these models typically up-regulate HOXA cluster genes, including HOXA5, HOXA7, HOXA9, and HOXA10. In addition, several of the NUP98 fusion proteins have been shown to inhibit differentiation of hematopoietic precursors and to increase self-renewal of hematopoietic stem or progenitor cells, providing a potential mechanism for malignant transformation. PMID:21948299

  14. RUNX1-ETO Leukemia.

    PubMed

    Lin, Shan; Mulloy, James C; Goyama, Susumu

    2017-01-01

    AML1-ETO leukemia is the most common cytogenetic subtype of acute myeloid leukemia, defined by the presence of t(8;21). Remarkable progress has been achieved in understanding the molecular pathogenesis of AML1-ETO leukemia. Proteomic surveies have shown that AML-ETO forms a stable complex with several transcription factors, including E proteins. Genome-wide transcriptome and ChIP-seq analyses have revealed the genes directly regulated by AML1-ETO, such as CEBPA. Several lines of evidence suggest that AML1-ETO suppresses endogenous DNA repair in cells to promote mutagenesis, which facilitates acquisition of cooperating secondary events. Furthermore, it has become increasingly apparent that a delicate balance of AML1-ETO and native AML1 is important to sustain the malignant cell phenotype. Translation of these findings into the clinical setting is just beginning.

  15. Tanespimycin and Cytarabine in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia, Acute Lymphoblastic Leukemia, Chronic Myelogenous Leukemia, Chronic Myelomonocytic Leukemia, or Myelodysplastic Syndromes

    ClinicalTrials.gov

    2013-09-27

    Accelerated Phase Chronic Myelogenous Leukemia; 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); Blastic Phase Chronic Myelogenous Leukemia; Chronic Myelomonocytic Leukemia; de Novo Myelodysplastic Syndromes; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Refractory Anemia With Excess Blasts in Transformation; Relapsing Chronic Myelogenous Leukemia; Secondary Acute Myeloid Leukemia; Secondary Myelodysplastic Syndromes

  16. Leukemia in benzene workers.

    PubMed

    Rinsky, R A; Young, R J; Smith, A B

    1981-01-01

    To evaluate the possible association between occupational exposure to benzene and subsequent death from leukemia, the National Institute for Occupational Safety and Health (NIOSH) conducted a retrospective cohort mortality study of workers who had been exposed to benzene in the manufacture of rubber hydrochloride at two locations in Ohio. Ascertainment of vital status was accomplished for 98% of the cohort. Among 748 workers who had at least one day of exposure to benzene between 1940 and 1950, seven deaths from leukemia occurred; from United States death rates standardized for sex, age, and calendar time period, only 1.25 leukemia deaths would have been expected (standardized mortality ratio = 560; p less than 0.001). Mean duration of exposure to benzene was brief, and 437 (58%) of the cohort were exposed for less than 1 year. Evaluation of leukemia mortality for those workers exposed five or more years showed an SMR of 2100. All leukemia deaths were myelocytic or monocytic in cell type. Four additional cases of leukemia have been reorganized in workers at the study locations, but occurred in persons not encompassed by the strict definition of the cohort. Reconstruction of past exposures to benzene at the two locations indicates that in some areas of the plant airborne benzene concentrations rose occasionally to several hundred parts per million (ppm), but that for the most part, employee eight-hour time-weighted averages (TWA) fell within the limits considered permissible at the time of exposure. These data corroborate an initial analysis of the same cohort by Infante et al, and indicate that benzene is a human carcinogen at a range of exposures not greatly above the current legal standard.

  17. A novel PRD I and TG binding activity involved in virus-induced transcription of IFN-A genes.

    PubMed Central

    Génin, P; Bragança, J; Darracq, N; Doly, J; Civas, A

    1995-01-01

    Comparative analysis of the inducible elements of the mouse interferon A4 and A11 gene promoters (IE-A4 and IE-A11) by transient transfection experiments, DNase 1 footprinting and electrophoretic mobility shift assays resulted in identification of a virus-induced binding activity suggested to be involved in NDV-induced activation of transcription of these genes. The virus-induced factor, termed VIF, is activated early by contact of virions with cells. It specifically recognizes the PRD I-like domain shared by both inducible elements, as well as the TG-like domain of IE-A4. This factor, distinct from the IRF-1, IRF-2 and the alpha F1 binding proteins and presenting a different affinity pattern from that of the TG protein, is proposed as a candidate for IFN-type I gene regulation. Images PMID:8559665

  18. Molecular cloning and functional characterization of the lycopene ε-cyclase gene via virus-induced gene silencing and its expression pattern in Nicotiana tabacum.

    PubMed

    Shi, Yanmei; Wang, Ran; Luo, Zhaopeng; Jin, Lifeng; Liu, Pingping; Chen, Qiansi; Li, Zefeng; Li, Feng; Wei, Chunyang; Wu, Mingzhu; Wei, Pan; Xie, He; Qu, Lingbo; Lin, Fucheng; Yang, Jun

    2014-08-22

    Lycopene ε-cyclase (ε-LCY) is a key enzyme that catalyzes the synthesis of α-branch carotenoids through the cyclization of lycopene. Two cDNA molecules encoding ε-LCY (designated Ntε-LCY1 and Ntε-LCY2) were cloned from Nicotiana tabacum. Ntε-LCY1 and Ntε-LCY2 are encoded by two distinct genes with different evolutionary origins, one originating from the tobacco progenitor, Nicotiana sylvestris, and the other originating from Nicotiana tomentosiformis. The two coding regions are 97% identical at the nucleotide level and 95% identical at the amino acid level. Transcripts of Ntε-LCY were detectable in both vegetative and reproductive organs, with a relatively higher level of expression in leaves than in other tissues. Subcellular localization experiments using an Ntε-LCY1-GFP fusion protein demonstrated that mature Ntε-LCY1 protein is localized within the chloroplast in Bright Yellow 2 suspension cells. Under low-temperature and low-irradiation stress, Ntε-LCY transcript levels substantially increased relative to control plants. Tobacco rattle virus (TRV)-mediated silencing of ε-LCY in Nicotiana benthamiana resulted in an increase of β-branch carotenoids and a reduction in the levels of α-branch carotenoids. Meanwhile, transcripts of related genes in the carotenoid biosynthetic pathway observably increased, with the exception of β-OHase in the TRV-ε-lcy line. Suppression of ε-LCY expression was also found to alleviate photoinhibition of Potosystem II in virus-induced gene silencing (VIGS) plants under low-temperature and low-irradiation stress. Our results provide insight into the regulatory role of ε-LCY in plant carotenoid biosynthesis and suggest a role for ε-LCY in positively modulating low temperature stress responses.

  19. Molecular Cloning and Functional Characterization of the Lycopene ε-Cyclase Gene via Virus-Induced Gene Silencing and Its Expression Pattern in Nicotiana tabacum

    PubMed Central

    Shi, Yanmei; Wang, Ran; Luo, Zhaopeng; Jin, Lifeng; Liu, Pingping; Chen, Qiansi; Li, Zefeng; Li, Feng; Wei, Chunyang; Wu, Mingzhu; Wei, Pan; Xie, He; Qu, Lingbo; Lin, Fucheng; Yang, Jun

    2014-01-01

    Lycopene ε-cyclase (ε-LCY) is a key enzyme that catalyzes the synthesis of α-branch carotenoids through the cyclization of lycopene. Two cDNA molecules encoding ε-LCY (designated Ntε-LCY1 and Ntε-LCY2) were cloned from Nicotiana tabacum. Ntε-LCY1 and Ntε-LCY2 are encoded by two distinct genes with different evolutionary origins, one originating from the tobacco progenitor, Nicotiana sylvestris, and the other originating from Nicotiana tomentosiformis. The two coding regions are 97% identical at the nucleotide level and 95% identical at the amino acid level. Transcripts of Ntε-LCY were detectable in both vegetative and reproductive organs, with a relatively higher level of expression in leaves than in other tissues. Subcellular localization experiments using an Ntε-LCY1-GFP fusion protein demonstrated that mature Ntε-LCY1 protein is localized within the chloroplast in Bright Yellow 2 suspension cells. Under low-temperature and low-irradiation stress, Ntε-LCY transcript levels substantially increased relative to control plants. Tobacco rattle virus (TRV)-mediated silencing of ε-LCY in Nicotiana benthamiana resulted in an increase of β-branch carotenoids and a reduction in the levels of α-branch carotenoids. Meanwhile, transcripts of related genes in the carotenoid biosynthetic pathway observably increased, with the exception of β-OHase in the TRV-ε-lcy line. Suppression of ε-LCY expression was also found to alleviate photoinhibition of Potosystem II in virus-induced gene silencing (VIGS) plants under low-temperature and low-irradiation stress. Our results provide insight into the regulatory role of ε-LCY in plant carotenoid biosynthesis and suggest a role for ε-LCY in positively modulating low temperature stress responses. PMID:25153631

  20. Development of Virus-Induced Gene Expression and Silencing Vector Derived from Grapevine Algerian Latent Virus

    PubMed Central

    Park, Sang-Ho; Choi, Hoseong; Kim, Semin; Cho, Won Kyong; Kim, Kook-Hyung

    2016-01-01

    Grapevine Algerian latent virus (GALV) is a member of the genus Tombusvirus in the Tombusviridae and infects not only woody perennial grapevine plant but also herbaceous Nicotiana benthamiana plant. In this study, we developed GALV-based gene expression and virus-induced gene silencing (VIGS) vectors in N. benthamiana. The GALV coat protein deletion vector, pGMG, was applied to express the reporter gene, green fluorescence protein (GFP), but the expression of GFP was not detected due to the necrotic cell death on the infiltrated leaves. The p19 silencing suppressor of GALV was engineered to inactivate its expression and GFP was successfully expressed with unrelated silencing suppressor, HC-Pro, from soybean mosaic virus. The pGMG vector was used to knock down magnesium chelatase (ChlH) gene in N. benthamaina and the silencing phenotype was clearly observed on systemic leaves. Altogether, the GALV-derived vector is expected to be an attractive tool for useful gene expression and VIGS vectors in grapevine as well as N. benthamiana. PMID:27493613

  1. Development of a virus induced gene silencing vector from a legumes infecting tobamovirus.

    PubMed

    Várallyay, Eva; Lichner, Zsuzsanna; Sáfrány, Judit; Havelda, Z; Salamon, P; Bisztray, Gy; Burgyán, J

    2010-12-01

    Medicago truncatula, the model plant of legumes, is well characterized, but there is only a little knowledge about it as a viral host. Viral vectors can be used for expressing foreign genes or for virus-induced gene silencing (VIGS), what is a fast and powerful tool to determine gene functions in plants. Viral vectors effective on Nicotiana benthamiana have been constructed from a number of viruses, however, only few of them were effective in other plants. A Tobamovirus, Sunnhemp mosaic virus (SHMV) systemically infects Medicago truncatula without causing severe symptoms. To set up a viral vector for Medicago truncatula, we prepared an infectious cDNA clone of SHMV. We constructed two VIGS vectors differing in the promoter element to drive foreign gene expression. The vectors were effective both in the expression and in the silencing of a transgene Green Fluorescent Protein (GFP) and in silencing of an endogenous gene Phytoene desaturase (PDS) on N. benthamiana. Still only one of the vectors was able to successfully silence the endogenous Chlorata 42 gene in M. truncatula.

  2. Incidence of Alpha-Herpes virus induced ocular disease in Suriname.

    PubMed

    Adhin, Malti R; Grunberg, Meritha G; Labadie-Bracho, Mergiory; Pawiroredjo, Jerrel

    2012-12-01

    Herpes simplex virus (HSV) infection of the corneal stroma is the most prominent cause of scar formation impairing visual acuity and HSV keratitis is the leading cause of corneal opacity throughout the world. Suriname lacked test systems for microbial causes of ocular disease, therefore a polymerase chain reaction-based Herpes virus assay was introduced, enabling prompt recognition, and timely treatment, preventing progressive eye damage. The incidence and epidemiology of Herpes simplex virus type 1 (HSV-1), type 2 (HSV-2), and varicella zoster virus (VZV) in ocular disease in Suriname was assessed. In a cross-sectional prospective study, ocular swabs were collected from 91 patients with a presumptive α-Herpes virus ocular infection attending the Academic Hospital between November 2008 and August 2010 and were tested by a PCR-based α-Herpes virus assay. Alpha-Herpes virus ophthalmic infections were caused predominantly by HSV-1 with a prevalence of 31%. The prevalences of VZV, HSV-2, and a mixed HSV-1/HSV-2 infection were 4%, 3%, and 2%, respectively. The first reported annual incidence of herpetic induced ocular disease in Suriname was estimated at 11.4 per 100,000 person-years (95% CI, 4.8-18.1). No clear age, ethnic or gender dependent difference in incidence was observed. The information obtained on α-Herpes virus positive ocular infections and the distribution of subtypes provided the first insight in the South American situation of α-Herpes virus induced ocular disease.

  3. Foxtail Mosaic Virus-Induced Gene Silencing in Monocot Plants1[OPEN

    PubMed Central

    Liu, Na; Xie, Ke; Jia, Qi; Zhao, Jinping; Chen, Tianyuan; Li, Huangai; Wei, Xiang; Diao, Xianmin; Hong, Yiguo

    2016-01-01

    Virus-induced gene silencing (VIGS) is a powerful technique to study gene function in plants. However, very few VIGS vectors are available for monocot plants. Here we report that Foxtail mosaic virus (FoMV) can be engineered as an effective VIGS system to induce efficient silencing of endogenous genes in monocot plants including barley (Hordeum vulgare L.), wheat (Triticum aestivum) and foxtail millet (Setaria italica). This is evidenced by FoMV-based silencing of phytoene desaturase (PDS) and magnesium chelatase in barley, of PDS and Cloroplastos alterados1 in foxtail millet and wheat, and of an additional gene IspH in foxtail millet. Silencing of these genes resulted in photobleached or chlorosis phenotypes in barley, wheat, and foxtail millet. Furthermore, our FoMV-based gene silencing is the first VIGS system reported for foxtail millet, an important C4 model plant. It may provide an efficient toolbox for high-throughput functional genomics in economically important monocot crops. PMID:27225900

  4. A virus-induced gene silencing approach to understanding alkaloid metabolism in Catharanthus roseus

    PubMed Central

    Liscombe, David K.; O’Connor, Sarah E.

    2011-01-01

    The anticancer agents vinblastine and vincristine are bisindole alkaloids derived from coupling vindoline and catharanthine, monoterpenoid indole alkaloids produced exclusively by Madagascar periwinkle (Catharanthus roseus) plants. Industrial production of vinblastine and vincristine currently relies on isolation from C. roseus leaves, a process that affords these compounds in 0.0003–0.01% yields. Metabolic engineering efforts to improve alkaloid content or provide alternative sources of the bisindole alkaloids ultimately rely on the isolation and characterization of the genes involved. Several vindoline biosynthetic genes have been isolated, and the cellular and subcellular organization of the corresponding enzymes has been well studied. However, due to the leaf-specific localization of vindoline biosynthesis, and the lack of production of this precursor in cell suspension and hairy root cultures of C. roseus, further elucidation of this pathway demands the development of reverse genetics approaches to assay gene function in planta. The bipartite pTRV vector system is a Tobacco Rattle Virus-based virus-induced gene silencing (VIGS) platform that has provided efficient and effective means to assay gene function in diverse plant systems. We have developed a VIGS method to investigate gene function in C. roseus plants using the pTRV vector system. The utility of this approach in understanding gene function in C. roseus leaves is demonstrated by silencing known vindoline biosynthetic genes previously characterized in vitro. PMID:21802100

  5. Compromised virus-induced gene silencing in RDR6-deficient plants.

    PubMed

    Vaistij, Fabián E; Jones, Louise

    2009-03-01

    RNA silencing in plants serves as a potent antiviral defense mechanism through the action of small interfering RNAs (siRNAs), which direct RNA degradation. siRNAs can be derived directly from the viral genome or via the action of host-encoded RNA-dependent RNA polymerases (RDRs). Plant genomes encode multiple RDRs, and it has been demonstrated that plants defective for RDR6 hyperaccumulate several classes of virus. In this study, we compared the effectiveness of virus-induced gene silencing (VIGS) and RNA-directed DNA methylation (RdDM) in wild-type and RDR6-deficient Nicotiana benthamiana plants. For the potexvirus Potato virus X (PVX) and the potyvirus Plum pox virus (PPV), the efficiency of both VIGS and RdDM were compromised in RDR6-defective plants despite accumulating high levels of viral siRNAs similar to infection of wild-type plants. The reduced efficiency of VIGS and RdDM was unrelated to the size class of siRNA produced and, at least for PVX, was not dependent on the presence of the virus-encoded silencing suppressor protein, 25K. We suggest that primary siRNAs produced from PVX and PPV in the absence of RDR6 may not be good effectors of silencing and that RDR6 is required to produce secondary siRNAs that drive a more effective antiviral response.

  6. Functional analyses of cellulose synthase genes in flax (Linum usitatissimum) by virus-induced gene silencing.

    PubMed

    Chantreau, Maxime; Chabbert, Brigitte; Billiard, Sylvain; Hawkins, Simon; Neutelings, Godfrey

    2015-12-01

    Flax (Linum usitatissimum) bast fibres are located in the stem cortex where they play an important role in mechanical support. They contain high amounts of cellulose and so are used for linen textiles and in the composite industry. In this study, we screened the annotated flax genome and identified 14 distinct cellulose synthase (CESA) genes using orthologous sequences previously identified. Transcriptomics of 'primary cell wall' and 'secondary cell wall' flax CESA genes showed that some were preferentially expressed in different organs and stem tissues providing clues as to their biological role(s) in planta. The development for the first time in flax of a virus-induced gene silencing (VIGS) approach was used to functionally evaluate the biological role of different CESA genes in stem tissues. Quantification of transcript accumulation showed that in many cases, silencing not only affected targeted CESA clades, but also had an impact on other CESA genes. Whatever the targeted clade, inactivation by VIGS affected plant growth. In contrast, only clade 1- and clade 6-targeted plants showed modifications in outer-stem tissue organization and secondary cell wall formation. In these plants, bast fibre number and structure were severely impacted, suggesting that the targeted genes may play an important role in the establishment of the fibre cell wall. Our results provide new fundamental information about cellulose biosynthesis in flax that should facilitate future plant improvement/engineering.

  7. Characterization of virus-induced gene silencing in tobacco plants infected with apple latent spherical virus.

    PubMed

    Yaegashi, H; Yamatsuta, T; Takahashi, T; Li, C; Isogai, M; Kobori, T; Ohki, S; Yoshikawa, N

    2007-01-01

    Apple latent spherical virus (ALSV) expressing green fluorescent protein (GFP-ALSV) was used for analysis of virus-induced gene silencing (VIGS) in tobacco plants expressing GFP (GFP-tobacco). In GFP-tobacco inoculated with GFP-ALSV, small dark spots appeared on inoculated leaves at 5 days post-inoculation (dpi), then expanded, and finally covered the whole area of the leaves after 12 dpi. Most of the fluorescence of upper leaves above the 12th true leaf disappeared at 21 dpi. Thus, GFP-ALSV infection efficiently triggered VIGS of a transgene (GFP gene) in tobacco plants. Analysis of GFP-silenced leaves showed that viral RNAs and proteins accumulated in all leaves where most GFP mRNA had been degraded. The siRNAs derived from ALSV-RNAs were not detected in samples from which siRNA of GFP mRNA could be easily detected. Direct tissue blot analysis showed that the spread of GFP-ALSV always preceded the induction of VIGS in infected leaves of GFP-tobacco. GFP leaf patch tests using Nicotiana benthamiana line 16c showed that Vp20, one of the three capsid proteins, is a silencing suppressor which interferes with systemic silencing.

  8. Common Viral Integration Sites Identified in Avian Leukosis Virus-Induced B-Cell Lymphomas

    PubMed Central

    Justice, James F.; Morgan, Robin W.

    2015-01-01

    ABSTRACT Avian leukosis virus (ALV) induces B-cell lymphoma and other neoplasms in chickens by integrating within or near cancer genes and perturbing their expression. Four genes—MYC, MYB, Mir-155, and TERT—have previously been identified as common integration sites in these virus-induced lymphomas and are thought to play a causal role in tumorigenesis. In this study, we employ high-throughput sequencing to identify additional genes driving tumorigenesis in ALV-induced B-cell lymphomas. In addition to the four genes implicated previously, we identify other genes as common integration sites, including TNFRSF1A, MEF2C, CTDSPL, TAB2, RUNX1, MLL5, CXorf57, and BACH2. We also analyze the genome-wide ALV integration landscape in vivo and find increased frequency of ALV integration near transcriptional start sites and within transcripts. Previous work has shown ALV prefers a weak consensus sequence for integration in cultured human cells. We confirm this consensus sequence for ALV integration in vivo in the chicken genome. PMID:26670384

  9. Virus-Induced Gene Silencing in Cultivated Cotton (Gossypium spp.) Using Tobacco Rattle Virus.

    PubMed

    Mustafa, Roma; Shafiq, Muhammad; Mansoor, Shahid; Briddon, Rob W; Scheffler, Brian E; Scheffler, Jodi; Amin, Imran

    2016-01-01

    The study described here has optimized the conditions for virus-induced gene silencing (VIGS) in three cultivated cotton species (Gossypium hirsutum, G. arboreum, and G. herbaceum) using a Tobacco rattle virus (TRV) vector. The system was used to silence the homolog of the Arabidopsis thaliana chloroplastos alterados 1 (AtCLA1) gene, involved in chloroplast development, in G. herbaceum, G. arboreum, and six commercial G. hirsutum cultivars. All plants inoculated with the TRV vector to silence CLA1 developed a typical albino phenotype indicative of silencing this gene. Although silencing in G. herbaceum and G. arboreum was complete, silencing efficiency differed for each G. hirsutum cultivar. Reverse transcriptase polymerase chain reaction (PCR) and real-time quantitative PCR showed a reduction in mRNA levels of the CLA1 homolog in all three species, with the highest efficiency (lowest CLA1 mRNA levels) in G. arboreum followed by G. herbaceum and G. hirsutum. The results indicate that TRV is a useful vector for VIGS in Gossypium species. However, selection of host cultivar is important. With the genome sequences of several cotton species recently becoming publicly available, this system has the potential to provide a very powerful tool for the rapid, large-scale reverse-genetic analysis of genes in Gossypium spp.

  10. Delineation of autoantibody repertoire through differential proteogenomics in hepatitis C virus-induced cryoglobulinemia

    PubMed Central

    Ogishi, Masato; Yotsuyanagi, Hiroshi; Moriya, Kyoji; Koike, Kazuhiko

    2016-01-01

    Antibodies cross-reactive to pathogens and autoantigens are considered pivotal in both infection control and accompanying autoimmunity. However, the pathogenic roles of autoantibodies largely remain elusive without a priori knowledge of disease-specific autoantigens. Here, through a novel quantitative proteogenomics approach, we demonstrated a successful identification of immunoglobulin variable heavy chain (VH) sequences highly enriched in pathological immune complex from clinical specimens obtained from a patient with hepatitis C virus-induced cryoglobulinemia (HCV-CG). Reconstructed single-domain antibodies were reactive to both HCV antigens and potentially liver-derived human proteins. Moreover, over the course of antiviral therapy, a substantial “de-evolution” of a distinct sub-repertoire was discovered, to which proteomically identified cryoprecipitation-prone autoantibodies belonged. This sub-repertoire was characterized by IGHJ6*03-derived, long, hydrophobic complementarity determining region (CDR-H3). This study provides a proof-of-concept of de novo mining of autoantibodies and corresponding autoantigen candidates in a disease-specific context in human, thus facilitating future reverse-translational research for the discovery of novel biomarkers and the development of antigen-specific immunotherapy against various autoantibody-related disorders. PMID:27403724

  11. Host genome integration and giant virus-induced reactivation of the virophage mavirus.

    PubMed

    Fischer, Matthias G; Hackl, Thomas

    2016-12-07

    Endogenous viral elements are increasingly found in eukaryotic genomes, yet little is known about their origins, dynamics, or function. Here we provide a compelling example of a DNA virus that readily integrates into a eukaryotic genome where it acts as an inducible antiviral defence system. We found that the virophage mavirus, a parasite of the giant Cafeteria roenbergensis virus (CroV), integrates at multiple sites within the nuclear genome of the marine protozoan Cafeteria roenbergensis. The endogenous mavirus is structurally and genetically similar to eukaryotic DNA transposons and endogenous viruses of the Maverick/Polinton family. Provirophage genes are not constitutively expressed, but are specifically activated by superinfection with CroV, which induces the production of infectious mavirus particles. Virophages can inhibit the replication of mimivirus-like giant viruses and an anti-viral protective effect of provirophages on their hosts has been hypothesized. We find that provirophage-carrying cells are not directly protected from CroV; however, lysis of these cells releases infectious mavirus particles that are then able to suppress CroV replication and enhance host survival during subsequent rounds of infection. The microbial host-parasite interaction described here involves an altruistic aspect and suggests that giant-virus-induced activation of provirophages might be ecologically relevant in natural protist populations.

  12. A Foxtail mosaic virus Vector for Virus-Induced Gene Silencing in Maize.

    PubMed

    Mei, Yu; Zhang, Chunquan; Kernodle, Bliss M; Hill, John H; Whitham, Steven A

    2016-06-01

    Plant viruses have been widely used as vectors for foreign gene expression and virus-induced gene silencing (VIGS). A limited number of viruses have been developed into viral vectors for the purposes of gene expression or VIGS in monocotyledonous plants, and among these, the tripartite viruses Brome mosaic virus and Cucumber mosaic virus have been shown to induce VIGS in maize (Zea mays). We describe here a new DNA-based VIGS system derived from Foxtail mosaic virus (FoMV), a monopartite virus that is able to establish systemic infection and silencing of endogenous maize genes homologous to gene fragments inserted into the FoMV genome. To demonstrate VIGS applications of this FoMV vector system, four genes, phytoene desaturase (functions in carotenoid biosynthesis), lesion mimic22 (encodes a key enzyme of the porphyrin pathway), iojap (functions in plastid development), and brown midrib3 (caffeic acid O-methyltransferase), were silenced and characterized in the sweet corn line Golden × Bantam. Furthermore, we demonstrate that the FoMV infectious clone establishes systemic infection in maize inbred lines, sorghum (Sorghum bicolor), and green foxtail (Setaria viridis), indicating the potential wide applications of this viral vector system for functional genomics studies in maize and other monocots. © 2016 American Society of Plant Biologists. All Rights Reserved.

  13. A Foxtail mosaic virus Vector for Virus-Induced Gene Silencing in Maize1[OPEN

    PubMed Central

    Mei, Yu; Kernodle, Bliss M.; Hill, John H.

    2016-01-01

    Plant viruses have been widely used as vectors for foreign gene expression and virus-induced gene silencing (VIGS). A limited number of viruses have been developed into viral vectors for the purposes of gene expression or VIGS in monocotyledonous plants, and among these, the tripartite viruses Brome mosaic virus and Cucumber mosaic virus have been shown to induce VIGS in maize (Zea mays). We describe here a new DNA-based VIGS system derived from Foxtail mosaic virus (FoMV), a monopartite virus that is able to establish systemic infection and silencing of endogenous maize genes homologous to gene fragments inserted into the FoMV genome. To demonstrate VIGS applications of this FoMV vector system, four genes, phytoene desaturase (functions in carotenoid biosynthesis), lesion mimic22 (encodes a key enzyme of the porphyrin pathway), iojap (functions in plastid development), and brown midrib3 (caffeic acid O-methyltransferase), were silenced and characterized in the sweet corn line Golden × Bantam. Furthermore, we demonstrate that the FoMV infectious clone establishes systemic infection in maize inbred lines, sorghum (Sorghum bicolor), and green foxtail (Setaria viridis), indicating the potential wide applications of this viral vector system for functional genomics studies in maize and other monocots. PMID:27208311

  14. Method: low-cost delivery of the cotton leaf crumple virus-induced gene silencing system

    PubMed Central

    2012-01-01

    Background We previously developed a virus-induced gene silencing (VIGS) vector for cotton from the bipartite geminivirusCotton leaf crumple virus (CLCrV). The original CLCrV VIGS vector was designed for biolistic delivery by a gene gun. This prerequisite limited the use of the system to labs with access to biolistic equipment. Here we describe the adaptation of this system for delivery by Agrobacterium (Agrobacterium tumefaciens). We also describe the construction of two low-cost particle inflow guns. Results The biolistic CLCrV vector was transferred into two Agrobacterium binary plasmids. Agroinoculation of the binary plasmids into cotton resulted in silencing and GFP expression comparable to the biolistic vector. Two homemade low-cost gene guns were used to successfully inoculate cotton (G. hirsutum) and N. benthamiana with either the CLCrV VIGS vector or the Tomato golden mosaic virus (TGMV) VIGS vector respectively. Conclusions These innovations extend the versatility of CLCrV-based VIGS for analyzing gene function in cotton. The two low-cost gene guns make VIGS experiments affordable for both research and teaching labs by providing a working alternative to expensive commercial gene guns. PMID:22853641

  15. A CRISPR-Based Screen Identifies Genes Essential for West-Nile-Virus-Induced Cell Death.

    PubMed

    Ma, Hongming; Dang, Ying; Wu, Yonggan; Jia, Gengxiang; Anaya, Edgar; Zhang, Junli; Abraham, Sojan; Choi, Jang-Gi; Shi, Guojun; Qi, Ling; Manjunath, N; Wu, Haoquan

    2015-07-28

    West Nile virus (WNV) causes an acute neurological infection attended by massive neuronal cell death. However, the mechanism(s) behind the virus-induced cell death is poorly understood. Using a library containing 77,406 sgRNAs targeting 20,121 genes, we performed a genome-wide screen followed by a second screen with a sub-library. Among the genes identified, seven genes, EMC2, EMC3, SEL1L, DERL2, UBE2G2, UBE2J1, and HRD1, stood out as having the strongest phenotype, whose knockout conferred strong protection against WNV-induced cell death with two different WNV strains and in three cell lines. Interestingly, knockout of these genes did not block WNV replication. Thus, these appear to be essential genes that link WNV replication to downstream cell death pathway(s). In addition, the fact that all of these genes belong to the ER-associated protein degradation (ERAD) pathway suggests that this might be the primary driver of WNV-induced cell death. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Recombinant infectious hematopoietic necrosis viruses induce protection for rainbow trout Oncorhynchus mykiss.

    PubMed

    Romero, Alejandro; Figueras, Antonio; Thoulouze, Maria-Isabel; Bremont, Michael; Novoa, Beatriz

    2008-07-07

    Infectious hematopoietic necrosis virus (IHNV) and viral hemorrhagic septicaemia virus (VHSV) are rhabdoviruses that infect salmonids, producing serious economic losses. Two recombinant IHN viruses were generated by reverse genetics. For one (rIHNV GFP) the IHNV NV gene was replaced with the green fluorescent protein (GFP) gene. In the other (rIHNV-Gvhsv GFP) the G gene was also exchanged for that of VHSV. No mortalities, external signs or histological lesions were observed in experimental infections conducted with the recombinant viruses. Neither the rIHNV GFP nor rIHNV-Gvhsv GFP was detected by RT-PCR in any of the examined tissues from experimentally infected fish. In order to assess their potential as vaccines against the wild type viruses, rainbow trout were vaccinated with the recombinant viruses by intraperitoneal injection and challenged 30 d later with virulent IHNV or VHSV. The GFP viruses provided protection against both wild type viruses. None of the recombinant viruses induced antibody production, and the expression of interferon (IFNalpha4) and interferon induced genes such as Mx protein and ISG-15 was not different to that of controls. The rIHNV-Gvhsv GFP did not inhibit cellular apoptosis as it was observed in an IHNV inoculated fish cell line. These studies suggest that the recombinant rIHNV-Gvhsv GFP is a promising candidate as a live recombinant vaccine and also provides a good model to further study viral pathogenicity and the molecular basis of protection against these viral infections.

  17. Disruption of Rpp1-mediated soybean rust immunity by virus-induced gene silencing.

    PubMed

    Cooper, Bret; Campbell, Kimberly B; McMahon, Michael B; Luster, Douglas G

    2013-01-01

    Phakopsora pachyrhizi, a fungus that causes rust disease on soybean, has potential to impart significant yield loss and disrupt food security and animal feed production. Rpp1 is a soybean gene that confers immunity to soybean rust, and it is important to understand how it regulates the soybean defense system and to use this knowledge to protect commercial crops. It was previously discovered that some soybean proteins resembling transcription factors accumulate in the nucleus of Rpp1 soybeans. To determine if they contribute to immunity, Bean pod mottle virus was used to attenuate or silence the expression of their genes. Rpp1 plants subjected to virus-induced gene silencing exhibited reduced amounts of RNA for 5 of the tested genes, and the plants developed rust-like symptoms after subsequent inoculation with fungal spores. Symptoms were associated with the accumulation of rust fungal RNA and protein. Silenced plants also had reduced amounts of RNA for the soybean Myb84 transcription factor and soybean isoflavone O-methyltransferase, both of which are important to phenylpropanoid biosynthesis and lignin formation, crucial components of rust resistance. These results help resolve some of the genes that contribute to Rpp1-mediated immunity and improve upon the knowledge of the soybean defense system. It is possible that these genes could be manipulated to enhance rust resistance in otherwise susceptible soybean cultivars.

  18. The development of Akabane virus-induced congenital abnormalities in cattle.

    PubMed

    Kirkland, P D; Barry, R D; Harper, P A; Zelski, R Z

    1988-06-11

    A prospective study of the incidence and severity of congenital deformities of calves, attributable to maternal infection by Akabane virus, was carried out on a population of 174 susceptible animals that were between one and nine months pregnant at the time of infection. The study was carried out in the Hunter Valley of New South Wales during 1983, after an epidemic of Akabane virus infection in late February to early March 1983. The incidence of virus-induced abnormalities in calves and fetuses was 17.8 per cent (31/174). The highest incidence of abnormalities occurred during the third and sixth months of gestation (27 to 29 per cent). The earliest abnormality was observed after infection at 76 days of gestation, and the last after infection at 249 days. The development of the pathological entities of hydranencephaly/porencephaly and arthrogryposis were found to be quite distinct. Cases of hydranencephaly and porencephaly developed after infection between 76 and 104 days of gestation whereas arthrogryposis developed after infection between 103 and 174 days of infection. It was concluded that the type of congenital deformity produced by maternal infection with Akabane virus was dependent on the stage of fetal development at the time of infection. The data suggest that the infection was transplacental and that fetuses of less than two months of age were protected from infection.

  19. Autophagy Genes Enhance Murine Gammaherpesvirus 68 Reactivation From Latency by Preventing Virus-induced Systemic Inflammation

    PubMed Central

    Park, Sunmin; Buck, Michael D.; Desai, Chandni; Zhang, Xin; Loginicheva, Ekaterina; Martinez, Jennifer; Freeman, Michael L.; Saitoh, Tatsuya; Akira, Shizuo; Guan, Jun-Lin; He, You-Wen; Blackman, Marcia A.; Handley, Scott A.; Levine, Beth; Green, Douglas R.; Reese, Tiffany A.; Artyomov, Maxim N.; Virgin, Herbert W.

    2016-01-01

    SUMMARY Host genes that regulate systemic inflammation upon chronic viral infection are incompletely understood. Murine γ-herpesvirus 68 (MHV68) infection is characterized by latency in macrophages, and reactivation is inhibited by Interferon-γ (IFN-γ). Using a Lysozyme-M-cre (LysMcre) expression system, we show that deletion of autophagy-related (Atg) genes Fip200, beclin 1, Atg14, Atg16L1, Atg7, Atg3, and Atg5, in the myeloid compartment, inhibited MHV68 reactivation in macrophages. Atg5-deficiency did not alter reactivation from B cells, and effects on reactivation from macrophages were not explained by alterations in productive viral replication or the establishment of latency. Rather, chronic MHV68 infection triggered increased systemic inflammation, increased T cell production of IFN-γ and an IFN-γ-induced transcriptional signature in macrophages from Atg gene-deficient mice. The Atg5-related reactivation defect was partially reversed by neutralization of IFN-γ. Thus Atg genes in myeloid cells dampen virus-induced systemic inflammation, creating an environment that fosters efficient MHV68 reactivation from latency. PMID:26764599

  20. The methyltransferase Setdb2 mediates virus-induced susceptibility to bacterial superinfection.

    PubMed

    Schliehe, Christopher; Flynn, Elizabeth K; Vilagos, Bojan; Richson, Udochuku; Swaminanthan, Savitha; Bosnjak, Berislav; Bauer, Lisa; Kandasamy, Richard K; Griesshammer, Isabel M; Kosack, Lindsay; Schmitz, Frank; Litvak, Vladimir; Sissons, James; Lercher, Alexander; Bhattacharya, Anannya; Khamina, Kseniya; Trivett, Anna L; Tessarollo, Lino; Mesteri, Ildiko; Hladik, Anastasiya; Merkler, Doron; Kubicek, Stefan; Knapp, Sylvia; Epstein, Michelle M; Symer, David E; Aderem, Alan; Bergthaler, Andreas

    2015-01-01

    Immune responses are tightly regulated to ensure efficient pathogen clearance while avoiding tissue damage. Here we report that Setdb2 was the only protein lysine methyltransferase induced during infection with influenza virus. Setdb2 expression depended on signaling via type I interferons, and Setdb2 repressed expression of the gene encoding the neutrophil attractant CXCL1 and other genes that are targets of the transcription factor NF-κB. This coincided with occupancy by Setdb2 at the Cxcl1 promoter, which in the absence of Setdb2 displayed diminished trimethylation of histone H3 Lys9 (H3K9me3). Mice with a hypomorphic gene-trap construct of Setdb2 exhibited increased infiltration of neutrophils during sterile lung inflammation and were less sensitive to bacterial superinfection after infection with influenza virus. This suggested that a Setdb2-mediated regulatory crosstalk between the type I interferons and NF-κB pathways represents an important mechanism for virus-induced susceptibility to bacterial superinfection.

  1. Virus-induced gene silencing of fiber-related genes in cotton.

    PubMed

    Tuttle, John R; Haigler, Candace H; Robertson, Dominique Niki

    2015-01-01

    Virus-Induced Gene Silencing (VIGS) is a useful method for transient downregulation of gene expression in crop plants. The geminivirus Cotton leaf crumple virus (CLCrV) has been modified to serve as a VIGS vector for persistent gene silencing in cotton. Here the use of Green Fluorescent Protein (GFP) is described as a marker for identifying silenced tissues in reproductive tissues, a procedure that requires the use of transgenic plants. Suggestions are given for isolating and cloning combinations of target and marker sequences so that the total length of inserted foreign DNA is between 500 and 750 bp. Using this strategy, extensive silencing is achieved with only 200-400 bp of sequence homologous to an endogenous gene, reducing the possibility of off-target silencing. Cotyledons can be inoculated using either the gene gun or Agrobacterium and will continue to show silencing throughout fruit and fiber development. CLCrV is not transmitted through seed, and VIGS is limited to genes expressed in the maternally derived seed coat and fiber in the developing seed. This complicates the use of GFP as a marker for VIGS because cotton fibers must be separated from unsilenced tissue in the seed to determine if they are silenced. Nevertheless, fibers from a large number of seeds can be rapidly screened following placement into 96-well plates. Methods for quantifying the extent of silencing using semiquantitative RT-PCR are given.

  2. Investigating Gene Function in Cereal Rust Fungi by Plant-Mediated Virus-Induced Gene Silencing.

    PubMed

    Panwar, Vinay; Bakkeren, Guus

    2017-01-01

    Cereal rust fungi are destructive pathogens, threatening grain production worldwide. Targeted breeding for resistance utilizing host resistance genes has been effective. However, breakdown of resistance occurs frequently and continued efforts are needed to understand how these fungi overcome resistance and to expand the range of available resistance genes. Whole genome sequencing, transcriptomic and proteomic studies followed by genome-wide computational and comparative analyses have identified large repertoire of genes in rust fungi among which are candidates predicted to code for pathogenicity and virulence factors. Some of these genes represent defence triggering avirulence effectors. However, functions of most genes still needs to be assessed to understand the biology of these obligate biotrophic pathogens. Since genetic manipulations such as gene deletion and genetic transformation are not yet feasible in rust fungi, performing functional gene studies is challenging. Recently, Host-induced gene silencing (HIGS) has emerged as a useful tool to characterize gene function in rust fungi while infecting and growing in host plants. We utilized Barley stripe mosaic virus-mediated virus induced gene silencing (BSMV-VIGS) to induce HIGS of candidate rust fungal genes in the wheat host to determine their role in plant-fungal interactions. Here, we describe the methods for using BSMV-VIGS in wheat for functional genomics study in cereal rust fungi.

  3. Four plant Dicers mediate viral small RNA biogenesis and DNA virus induced silencing

    PubMed Central

    Blevins, Todd; Rajeswaran, Rajendran; Shivaprasad, Padubidri V.; Beknazariants, Daria; Si-Ammour, Azeddine; Park, Hyun-Sook; Vazquez, Franck; Robertson, Dominique; Meins, Frederick; Hohn, Thomas; Pooggin, Mikhail M.

    2006-01-01

    Like other eukaryotes, plants use DICER-LIKE (DCL) proteins as the central enzymes of RNA silencing, which regulates gene expression and mediates defense against viruses. But why do plants like Arabidopsis express four DCLs, a diversity unmatched by other kingdoms? Here we show that two nuclear DNA viruses (geminivirus CaLCuV and pararetrovirus CaMV) and a cytoplasmic RNA tobamovirus ORMV are differentially targeted by subsets of DCLs. DNA virus-derived small interfering RNAs (siRNAs) of specific size classes (21, 22 and 24 nt) are produced by all four DCLs, including DCL1, known to process microRNA precursors. Specifically, DCL1 generates 21 nt siRNAs from the CaMV leader region. In contrast, RNA virus infection is mainly affected by DCL4. While the four DCLs are partially redundant for CaLCuV-induced mRNA degradation, DCL4 in conjunction with RDR6 and HEN1 specifically facilitates extensive virus-induced silencing in new growth. Additionally, we show that CaMV infection impairs processing of endogenous RDR6-derived double-stranded RNA, while ORMV prevents HEN1-mediated methylation of small RNA duplexes, suggesting two novel viral strategies of silencing suppression. Our work highlights the complexity of virus interaction with host silencing pathways and suggests that DCL multiplicity helps mediate plant responses to diverse viral infections. PMID:17090584

  4. Graft-accelerated virus-induced gene silencing facilitates functional genomics in rose flowers.

    PubMed

    Yan, Huijun; Shi, Shaochuan; Ma, Nan; Cao, Xiaoqian; Zhang, Hao; Qiu, Xianqin; Wang, Qigang; Jian, Hongying; Zhou, Ningning; Zhang, Zhao; Tang, Kaixue

    2017-09-12

    Rose has emerged as a model ornamental plant for studies of flower development, senescence, and morphology, as well as the metabolism of floral fragrances and colors. Virus-induced gene silencing (VIGS) has long since been used in functional genomics studies of rose by vacuum infiltration of cuttings or seedlings with an Agrobacterium suspension carrying TRV-derived vectors. However, VIGS in rose flowers remains a challenge because of its low efficiency and long time to silencing. Here we present a novel and rapid VIGS method that can be used to analyze gene function in rose, called 'graft-accelerated VIGS', where axillary sprouts are cut off the rose plant and vacuum infiltrated with Agrobacterium. The inoculated scions are then grafted back onto the plants to flower and silencing phenotypes can be observed within five weeks post infiltration. Using this new method, we successfully silenced the expression of the RhDFR1, RhAG, and RhNUDX1 in rose flowers, and affected their color, petal number, as well as fragrance, respectively. This grafting method will facilitate high-throughput functional analysis of genes in rose flowers. Importantly, it may also be applied to other woody species that are not currently amenable to VIGS by conventional leaf or plantlet/seedling infiltration methods. This article is protected by copyright. All rights reserved.

  5. Tobacco rattle virus-based virus-induced gene silencing in Nicotiana benthamiana.

    PubMed

    Senthil-Kumar, Muthappa; Mysore, Kirankumar S

    2014-07-01

    Tobacco rattle virus (TRV)-based virus-induced gene silencing (VIGS) is widely used in various plant species to downregulate the expression of a target plant gene. TRV is a bipartite, positive-strand RNA virus with the TRV1 and TRV2 genomes. To induce post-transcriptional gene silencing (PTGS), the TRV2 genome is genetically modified to carry a fragment of the target gene and delivered into the plant (along with the TRV1 genome) by agroinoculation. TRV1- and TRV2-carrying Agrobacterium strains are then co-inoculated into 3-week-old plant leaves by one of three methods: a needleless syringe, the agrodrench method or by pricking with a toothpick. Target gene silencing occurs in the newly developed noninoculated leaves within 2-3 weeks of TRV inoculation. The TRV-VIGS protocol described here takes only 4 weeks to implement, and it is faster and easier to perform than other gene silencing techniques that are currently available. Although we use Nicotiana benthamiana as an example, the protocol is adaptable to other plant species.

  6. Disruption of Rpp1-mediated soybean rust immunity by virus-induced gene silencing

    PubMed Central

    Cooper, Bret; Campbell, Kimberly B; McMahon, Michael B; Luster, Douglas G

    2013-01-01

    Phakopsora pachyrhizi, a fungus that causes rust disease on soybean, has potential to impart significant yield loss and disrupt food security and animal feed production. Rpp1 is a soybean gene that confers immunity to soybean rust, and it is important to understand how it regulates the soybean defense system and to use this knowledge to protect commercial crops. It was previously discovered that some soybean proteins resembling transcription factors accumulate in the nucleus of Rpp1 soybeans. To determine if they contribute to immunity, Bean pod mottle virus was used to attenuate or silence the expression of their genes. Rpp1 plants subjected to virus-induced gene silencing exhibited reduced amounts of RNA for 5 of the tested genes, and the plants developed rust-like symptoms after subsequent inoculation with fungal spores. Symptoms were associated with the accumulation of rust fungal RNA and protein. Silenced plants also had reduced amounts of RNA for the soybean Myb84 transcription factor and soybean isoflavone O-methyltransferase, both of which are important to phenylpropanoid biosynthesis and lignin formation, crucial components of rust resistance. These results help resolve some of the genes that contribute to Rpp1-mediated immunity and improve upon the knowledge of the soybean defense system. It is possible that these genes could be manipulated to enhance rust resistance in otherwise susceptible soybean cultivars. PMID:24401541

  7. Role of TNF-α in virus-induced airway hyperresponsiveness and neuronal M2 muscarinic receptor dysfunction

    PubMed Central

    Nie, Zhenying; Scott, Gregory D; Weis, Patrick D; Itakura, Asako; Fryer, Allison D; Jacoby, David B

    2011-01-01

    BACKGROUND AND PURPOSE Infections with respiratory viruses induce exacerbations of asthma, increase acetylcholine release and potentiate vagally mediated bronchoconstriction by blocking inhibitory M2 muscarinic receptors on parasympathetic neurons. Here we test whether virus-induced M2 receptor dysfunction and airway hyperresponsiveness are tumour necrosis factor-alpha (TNF-α) dependent. EXPERIMENTAL APPROACH Guinea pigs were pretreated with etanercept or phosphate-buffered saline 24 h before intranasal infection with parainfluenza. Four days later, pulmonary inflation pressure, heart rate and blood pressure were measured. M2 receptor function was assessed by the potentiation by gallamine (an M2 receptor antagonist) of bronchoconstriction caused by electrical stimulation of the vagus nerves and measured as increased pulmonary inflation pressure. Human airway epithelial cells were infected with influenza and TNF-α concentration in supernatant was measured before supernatant was applied to human neuroblastoma cells. M2 receptor expression in these neuroblastoma cells was measured by qRT-PCR. KEY RESULTS Influenza-infected animals were hyperresponsive to vagal stimulation but not to intravenous ACh. Gallamine did not potentiate vagally induced bronchoconstriction in virus-infected animals, indicating M2 receptor dysfunction. Etanercept prevented virus-induced airway hyperresponsiveness and M2 receptor dysfunction, without changing lung viral titres. Etanercept caused a non-significant decrease in total cells, macrophages and neutrophils in bronchoalveolar lavage. Influenza infection significantly increased TNF-α release from isolated epithelial cells, sufficient to decrease M2 receptors in neuroblastoma cells. This ability of supernatants from infected epithelial cells to inhibit M2 receptor expression was blocked by etanercept. CONCLUSIONS AND IMPLICATIONS TNF-α is a key mediator of virus-induced M2 muscarinic receptor dysfunction and airway hyperresponsiveness

  8. Targeting DOT1L and HOX Gene Expression in MLL-Rearranged Leukemia and Beyond

    PubMed Central

    Chen, Chun-Wei; Armstrong, Scott A.

    2015-01-01

    Leukemias harboring mixed lineage leukemia (MLL1) gene abnormalities are associated with poor clinical outcomes and new therapeutic approaches are desperately needed. Rearrangement of the MLL1 gene generates chimeric proteins that fuse the NH3-terminus of MLL1 to the COOH-terminus of its translocation partners. These MLL1-fusion oncoproteins drive the expression of homeobox genes such as HOXA cluster genes and MEIS1, which are known to induce leukemic transformation of hematopoietic progenitors. Genome-wide histone methylation studies have revealed that the abnormal expression of MLL1-fusion target genes is associated with high levels of H3K79 methylation at these gene loci. The only known enzyme that catalyzes methylation of H3K79 is disruptor of telomeric-silencing 1-like (DOT1L). Loss-of-function mouse models as well as small molecular inhibitors of DOT1L demonstrate that leukemias driven by MLL1-translocations are dependent on DOT1L enzymatic activity for proliferation and for the maintenance of HOXA gene expression. Furthermore, DOT1L also appears to be important for HOXA gene expression in other settings including leukemias with select genetic abnormalities. These discoveries have established a foundation for disease-specific therapies that target chromatin modifications in highly malignant leukemias harboring specific genetic abnormalities. This review focuses on the molecular mechanisms underlying MLL1-translocation-driven leukemogenesis, and the latest progress on DOT1L-targeted epigenetic therapies for MLL1-rearranged and other leukemias. PMID:26118503

  9. Megakaryocytic blast crisis as a presenting manifestation of chronic myeloid leukemia.

    PubMed

    Pullarkat, Sheeja T; Vardiman, James W; Slovak, Marilyn L; Rao, Dinesh S; Rao, Nagesh P; Bedell, Victoria; Said, Jonathan W

    2008-11-01

    Acute megakaryocytic leukemia is a rare form of acute myelogenous leukemia and may occur either de novo or by transformation of a preexisting myelodysplastic or myeloproliferative process including blast crisis of chronic myeloid leukemia (CML). Megakaryocytic blast crisis as the presenting manifestation of CML is extremely rare. We describe such a patient with no prior hematologic disease who presented with acute megakaryoblastic leukemia and extramedullary involvement, in whom the leukemic cells carried the BCR-ABL1 translocation as part of a complex karyotype. Using targeted sequential fluorescence in situ hybridization (T-FISH) technique, we detected two copies of BCR-ABL1 fusion gene in the leukemic blasts while the neutrophils carried a single copy of BCR-ABL1 fusion gene, thereby proving the origin of the megakaryoblastic leukemia from a previously undiagnosed CML clone. Blast crisis as a presenting manifestation of CML is rare and detecting clonal evolution of acute leukemia by specialized cytogenetic techniques may have important diagnostic and therapeutic implications.

  10. Frequencies and prognostic impact of RAS mutations in MLL-rearranged acute lymphoblastic leukemia in infants

    PubMed Central

    Driessen, Emma M.C.; van Roon, Eddy H.J.; Spijkers-Hagelstein, Jill A.P.; Schneider, Pauline; de Lorenzo, Paola; Valsecchi, Maria Grazia; Pieters, Rob; Stam, Ronald W.

    2013-01-01

    Acute lymphoblastic leukemia in infants represents an aggressive malignancy associated with a high incidence (approx. 80%) of translocations involving the Mixed Lineage Leukemia (MLL) gene. Attempts to mimic Mixed Lineage Leukemia fusion driven leukemogenesis in mice raised the question whether these fusion proteins require secondary hits. RAS mutations are suggested as candidates. Earlier results on the incidence of RAS mutations in Mixed Lineage Leukemia-rearranged acute lymphoblastic leukemia are inconclusive. Therefore, we studied frequencies and relation with clinical parameters of RAS mutations in a large cohort of infant acute lymphoblastic leukemia patients. Using conventional sequencing analysis, we screened neuroblastoma RAS viral (v-ras) oncogene homolog gene (NRAS), v-Ki-ras Kirsten rat sarcoma viral oncogene homolog gene (KRAS), and v-raf murine sarcoma viral oncogene homolog B1 gene (BRAF) for mutations in a large cohort (n=109) of infant acute lymphoblastic leukemia patients and studied the mutations in relation to several clinical parameters, and in relation to Homeobox gene A9 expression and the presence of ALL1 fused gene 4-Mixed Lineage Leukemia (AF4-MLL). Mutations were detected in approximately 14% of all cases, with a higher frequency of approximately 24% in t(4;11)-positive patients (P=0.04). Furthermore, we identified RAS mutations as an independent predictor (P=0.019) for poor outcome in Mixed Lineage Leukemia-rearranged infant acute lymphoblastic leukemia, with a hazard ratio of 3.194 (95% confidence interval (CI):1.211–8.429). Also, RAS-mutated infants have higher white blood cell counts at diagnosis (P=0.013), and are more resistant to glucocorticoids in vitro (P<0.05). Finally, we demonstrate that RAS mutations, and not the lack of Homeobox gene A9 expression nor the expression of AF4-MLL are associated with poor outcome in t(4;11)-rearranged infants. We conclude that the presence of RAS mutations in Mixed Lineage Leukemia

  11. Crystal Structure of Menin Reveals Binding Site for Mixed Lineage Leukemia (MLL) Protein

    SciTech Connect

    Murai, Marcelo J.; Chruszcz, Maksymilian; Reddy, Gireesh; Grembecka, Jolanta; Cierpicki, Tomasz

    2014-10-02

    Menin is a tumor suppressor protein that is encoded by the MEN1 (multiple endocrine neoplasia 1) gene and controls cell growth in endocrine tissues. Importantly, menin also serves as a critical oncogenic cofactor of MLL (mixed lineage leukemia) fusion proteins in acute leukemias. Direct association of menin with MLL fusion proteins is required for MLL fusion protein-mediated leukemogenesis in vivo, and this interaction has been validated as a new potential therapeutic target for development of novel anti-leukemia agents. Here, we report the first crystal structure of menin homolog from Nematostella vectensis. Due to a very high sequence similarity, the Nematostella menin is a close homolog of human menin, and these two proteins likely have very similar structures. Menin is predominantly an {alpha}-helical protein with the protein core comprising three tetratricopeptide motifs that are flanked by two {alpha}-helical bundles and covered by a {beta}-sheet motif. A very interesting feature of menin structure is the presence of a large central cavity that is highly conserved between Nematostella and human menin. By employing site-directed mutagenesis, we have demonstrated that this cavity constitutes the binding site for MLL. Our data provide a structural basis for understanding the role of menin as a tumor suppressor protein and as an oncogenic co-factor of MLL fusion proteins. It also provides essential structural information for development of inhibitors targeting the menin-MLL interaction as a novel therapeutic strategy in MLL-related leukemias.

  12. Cytokines Interleukin 4 (IL-4) and Interleukin 10 (IL-10) Gene Polymorphisms as Potential Host Susceptibility Factors in Virus-Induced Encephalitis.

    PubMed

    Yu, Ying; Chen, Ying; Wang, Feng-Ling; Sun, Jing; Li, Hai-Jun; Liu, Jia-Ming

    2017-09-22

    BACKGROUND This study aimed to analyze and explore the relationship between the cytokines IL-4 and IL-10 in relation to gene polymorphism and their respective effects on the susceptibility to virus-induced encephalitis. MATERIAL AND METHODS From January 2012 to June 2013, 112 patients with virus-induced encephalitis (the case group and 109 healthy individuals (the control group) were recruited for the purposes of this study. The functional variations that IL-4 and IL-10 genes exhibit were detected through the use of a function analysis and selection tool for single-nucleotide polymorphisms (FASTSNP). The genotypes of IL-4 were rs2227283 and IL-4 rs2227288, and the genotypes of IL-10 were rs1800871 and IL-10 rs1800872. These genotypes were respectively assessed using direct sequencing. RESULTS IL-4 rs2227283 and IL-10 rs1800871 have no correlation in with risk of virus-induced encephalitis (both P>0.05) GA and AA genotypes were related to IL-4 rs2227288 and GT, while TT and GT + TT genotypes were related to IL-10 rs1800872. These were highlighted as being risk factors in virus-induced encephalitis (all P<0.05). However, the duration of fever, white blood cell (WBC) count, C-reactive protein (CRP), neutrophils, and lymphocytes and monocytes of virus-induced encephalitis patients with IL-4 rs2227288 and IL-10 rs1800872 all displayed significant differences (all P<0.05). Frequencies of GAGT and CAGT haplotypes were evaluated and deemed to be of statistical significance and subsequently were highlighted as being risk factors in virus-induced encephalitis (all P<0.05). CONCLUSIONS IL-4 rs2227288 and IL-10 rs1800872 may contribute to an increased risk for virus-induced encephalitis. Through use of direct sequencing, we showed that genotypes of IL-4 rs2227288 and IL-10 rs1800872 may have particular host susceptibility to virus-induced encephalitis.

  13. The Fusion Energy Option

    NASA Astrophysics Data System (ADS)

    Dean, Stephen O.

    2004-06-01

    Presentations from a Fusion Power Associates symposium, The Fusion Energy Option, are summarized. The topics include perspectives on fossil fuel reserves, fusion as a source for hydrogen production, status and plans for the development of inertial fusion, planning for the construction of the International Thermonuclear Experimental Reactor, status and promise of alternate approaches to fusion and the need for R&D now on fusion technologies.

  14. Detection of BCR-ABL Fusion mRNA Using Reverse Transcriptase Loop-mediated Isothermal Amplification

    SciTech Connect

    Dugan, L C; Hall, S; Kohlgruber, A; Urbin, S; Torres, C; Wilson, P

    2011-12-08

    RT-PCR is commonly used for the detection of Bcr-Abl fusion transcripts in patients diagnosed with chronic myelogenous leukemia, CML. Two fusion transcripts predominate in CML, Br-Abl e13a2 and e14a2. They have developed reverse transcriptase isothermal loop-mediated amplification (RT-LAMP) assays to detect these two fusion transcripts along with the normal Bcr transcript.

  15. Revitalizing Fusion via Fission Fusion

    NASA Astrophysics Data System (ADS)

    Manheimer, Wallace

    2001-10-01

    Existing tokamaks could generate significant nuclear fuel. TFTR, operating steady state with DT might generate enough fuel for a 300 MW nuclear reactor. The immediate goals of the magnetic fusion program would necessarily shift from a study of advanced plasma regimes in larger sized devices, to mostly known plasmas regimes, but at steady state or high duty cycle operation in DT plasmas. The science and engineering of breeding blankets would be equally important. Follow on projects could possibly produce nuclear fuel in large quantity at low price. Although today there is strong opposition to nuclear power in the United States, in a 21st century world of 10 billion people, all of whom will demand a middle class life style, nuclear energy will be important. Concern over greenhouse gases will also drive the world toward nuclear power. There are studies indicating that the world will need 10 TW of carbon free energy by 2050. It is difficult to see how this can be achieved without the breeding of nuclear fuel. By using the thorium cycle, proliferation risks are minimized. [1], [2]. 1 W. Manheimer, Fusion Technology, 36, 1, 1999, 2.W. Manheimer, Physics and Society, v 29, #3, p5, July, 2000

  16. Reversible conformational changes and fusion activity of rabies virus glycoprotein.

    PubMed Central

    Gaudin, Y; Tuffereau, C; Segretain, D; Knossow, M; Flamand, A

    1991-01-01

    In an attempt to understand the implication of the rabies virus glycoprotein (G) in the first steps of the viral cycle, we studied the pH dependence of virus-induced fusion and hemagglutination, as well as modifications of the structure and properties of the viral glycoprotein following pH acidification. Our results suggest that the G protein adopts at least three distinct configurations, each associated with different properties. At neutral pH, G did not fuse membranes or hemagglutinate erythrocytes. It was insensitive to digestion with bromelain and trypsin. At pH 6.4, the glycoprotein became sensitive to proteases. Hemagglutination was at its maximum and then sharply decreased with the pH. No fusion was detected. Aggregation of virus was also observed. The third configuration, at below pH 6.1, was associated with the appearance of fusion. Some neutralizing monoclonal antibodies were able to differentiate these three configurations. Preincubation of the virus at below pH 6 inhibited fusion, but this inhibition, like the structural modifications of the glycoprotein, was reversible when G was reincubated at neutral pH. Images PMID:1870204

  17. Vertigo as the First Sign of Chronic Myeloid Leukemia: A Case Report and Literature Review

    PubMed Central

    Martín-Hernández, Rubén; Macías-Rodríguez, Diego Hernando; Martín-Sánchez, Víctor; Cordero-Civantos, Cristina; Santa Cruz-Ruiz, Santiago; Batuecas-Caletrio, Ángel

    2013-01-01

    Acute vestibular deficit as the first sign of leukemia is extremely rare. The literature shows some cases of sudden hearing loss accompanied by instability and associated with hyperviscosity syndrome. We present the case of a patient who presents a harmonic vestibular deficit of the right ear. The complementary studies revealed an abnormally high level of leukocytes. A peripheral blood cytogenetic analysis is performed due to a high suspicion of leukemia, and the results show BCR/ABL fusion gene with a cut point in the M-BCR region, which confirms the diagnosis of chronic myeloid leukemia. In this case we detail the importance of taking hematological disorders into consideration in the differential diagnosis of patients with otoneurological symptoms, and we also review the etiopathogenic mechanisms, symptoms, diagnosis, and therapeutic options for chronic myeloid leukemia with sudden hearing loss and vertigo. PMID:23476855

  18. LEUKEMIA-ASSOCIATED TRANSPLANTATION ANTIGENS RELATED TO MURINE LEUKEMIA VIRUS

    PubMed Central

    Sato, H.; Boyse, E. A.; Aoki, T.; Iritani, C.; Old, L. J.

    1973-01-01

    Two BALB radiation leukemias are strongly rejected by hybrids of BALB with certain other mouse strains, although BALB mice themselves exhibit no detectable resistance whatever. Hybrids immunized with progressively increased inocula are resistant to 200 x 106 or more leukemia cells; their serum is cytotoxic for the leukemia cells in vitro and protects BALB mice against challenge with these BALB leukemias. The antigenic system thus identified has been named X.1. In (BALB x B6) hybrids the major determinant of resistance was shown to be a B6 gene in the K region of H-2. This is likely to be the Rgv-1 (Resistance to gross virus) locus of Lilly, which may thus be identified in this case as an Ir (Immune response) allele conferring ability to respond to X.1 antigen on MuLV and leukemia cells, and so responsible for production of X.1 antibody and the rejection of X.1+ leukemia cells by hybrid mice. Immunoelectron microscopy with X.1 antiserum (from immunized hybrids) shows labeling both on the cell surface and on virions produced by the leukemia cells. It is not known whether X.1 comprises only one or more than one antigen. Three radiation-induced BALB leukemias, one A strain radiation-induced leukemia, and 15/15 AKR primary spontaneous leukemias were typed X.1+ by the cytotoxicity test. Several other leukemias, including one induced by passage A Gross virus and one long-transplanted AKR ascites leukemia carried in (B6 x AKR)F1 hybrids, were X.1-. Normal mice of strains with a high incidence of leukemia and one other strain (129) express X.1 antigen, but evidently in amounts too small for certain detection in vitro; by the method of absorption in vivo, however, these strains could be typed X.1+ and other strains X.1-. We ascribe the X.1 antigen system tentatively to a sub-type of MuLV that is not passage A Gross virus and is probably not the dominant sub-type in strains with a high incidence of leukemia. After repeated passage in hybrids, one of the BALB leukemias became

  19. Leukemia and Benzene

    PubMed Central

    Snyder, Robert

    2012-01-01

    Excessive exposure to benzene has been known for more than a century to damage the bone marrow resulting in decreases in the numbers of circulating blood cells, and ultimately, aplastic anemia. Of more recent vintage has been the appreciation that an alternative outcome of benzene exposure has been the development of one or more types of leukemia. While many investigators agree that the array of toxic metabolites, generated in the liver or in the bone marrow, can lead to traumatic bone marrow injury, the more subtle mechanisms leading to leukemia have yet to be critically dissected. This problem appears to have more general interest because of the recognition that so-called “second cancer” that results from prior treatment with alkylating agents to yield tumor remissions, often results in a type of leukemia reminiscent of benzene-induced leukemia. Furthermore, there is a growing literature attempting to characterize the fine structure of the marrow and the identification of so called “niches” that house a variety of stem cells and other types of cells. Some of these “niches” may harbor cells capable of initiating leukemias. The control of stem cell differentiation and proliferation via both inter- and intra-cellular signaling will ultimately determine the fate of these transformed stem cells. The ability of these cells to avoid checkpoints that would prevent them from contributing to the leukemogenic response is an additional area for study. Much of the study of benzene-induced bone marrow damage has concentrated on determining which of the benzene metabolites lead to leukemogenesis. The emphasis now should be directed to understanding how benzene metabolites alter bone marrow cell biology. PMID:23066403

  20. What Are the Key Statistics about Acute Lymphocytic Leukemia?

    MedlinePlus

    ... Leukemia (ALL) What Are the Key Statistics About Acute Lymphocytic Leukemia? The American Cancer Society’s estimates for acute lymphocytic ... Acute Lymphocytic Leukemia Research and Treatment? More In Acute Lymphocytic Leukemia About Acute Lymphocytic Leukemia Causes, Risk Factors, and ...

  1. Do We Know What Causes Chronic Myelomonocytic Leukemia?

    MedlinePlus

    ... Prevention Do We Know What Causes Chronic Myelomonocytic Leukemia? Some cases of chronic myelomonocytic leukemia (CMML) are ... Myelomonocytic Leukemia Be Prevented? More In Chronic Myelomonocytic Leukemia About Chronic Myelomonocytic Leukemia Causes, Risk Factors, and ...

  2. Radiation inactivation analysis of influenza virus reveals different target sizes for fusion, leakage, and neuraminidase activities

    SciTech Connect

    Gibson, S.; Jung, C.Y.; Takahashi, M.; Lenard, J.

    1986-10-07

    The size of the functional units responsible for several activities carried out by the influenza virus envelope glycoproteins was determined by radiation inactivation analysis. Neuraminidase activity, which resides in the glycoprotein NA, was inactivated exponentially with an increasing radiation dose, yielding a target size of 94 +/- 5 kilodaltons (kDa), in reasonable agreement with that of the disulfide-bonded dimer (120 kDa). All the other activities studied are properties of the HA glycoprotein and were normalized to the known molecular weight of the neuraminidase dimer. Virus-induced fusion activity was measured by two phospholipid dilution assays: relief of energy transfer between N-(7-nitro-2,1,3-benzoxadiazol-4-yl)dipalmitoyl-L-alpha- phosphatidylethanolamine (N-NBD-PE) and N-(lissamine rhodamine B sulfonyl)-dioleoyl-L-alpha-phosphatidylethanolamine (N-Rh-PE) in target liposomes and relief of self-quenching of N-Rh-PE in target liposomes. Radiation inactivation of fusion activity proceeded exponentially with radiation dose, yielding normalized target sizes of 68 +/- 6 kDa by assay i and 70 +/- 4 kDa by assay ii. These values are close to the molecular weight of a single disulfide-bonded (HA1 + HA2) unit (75 kDa), the monomer of the HA trimer. A single monomer is thus inactivated by each radiation event, and each monomer (or some part of it) constitutes a minimal functional unit capable of mediating fusion. Virus-induced leakage of calcein from target liposomes and virus-induced leakage of hemoglobin from erythrocytes (hemolysis) both showed more complex inactivation behavior: a pronounced shoulder was present in both inactivation curves, followed by a steep drop in activity at higher radiation levels.

  3. AKT capture by feline leukemia virus.

    PubMed

    Kawamura, Maki; Umehara, Daigo; Odahara, Yuka; Miyake, Ariko; Ngo, Minh Ha; Ohsato, Yoshiharu; Hisasue, Masaharu; Nakaya, Masa-Aki; Watanabe, Shinya; Nishigaki, Kazuo

    2017-04-01

    Oncogene-containing retroviruses are generated by recombination events between viral and cellular sequences, a phenomenon called "oncogene capture". The captured cellular genes, referred to as "v-onc" genes, then acquire new oncogenic properties. We report a novel feline leukemia virus (FeLV), designated "FeLV-AKT", that has captured feline c-AKT1 in feline lymphoma. FeLV-AKT contains a gag-AKT fusion gene that encodes the myristoylated Gag matrix protein and the kinase domain of feline c-AKT1, but not its pleckstrin homology domain. Therefore, it differs structurally from the v-Akt gene of murine retrovirus AKT8. AKT may be involved in the mechanisms underlying malignant diseases in cats.

  4. Tiotropium Attenuates Virus-Induced Pulmonary Inflammation in Cigarette Smoke–Exposed Mice

    PubMed Central

    Bucher, Hannes; Duechs, Matthias J.; Tilp, Cornelia; Jung, Birgit

    2016-01-01

    Viral infections trigger exacerbations in chronic obstructive pulmonary disease (COPD), and tiotropium, a M3 receptor antagonist, reduces exacerbations in patients by unknown mechanisms. In this report, we investigated whether tiotropium has anti-inflammatory effects in mice exposed to cigarette smoke (CS) and infected with influenza virus A/PR/8/34 (H1N1) or respiratory syncytial virus (RSV) and compared these effects with those of steroid fluticasone and PDE4-inhibitor roflumilast. Mice were exposed to CS; infected with H1N1 or RSV; and treated with tiotropium, fluticasone, or roflumilast. The amount of cells and cytokine levels in the airways, lung function, and viral load was determined. NCI-H292 cells were infected with H1N1 or RSV and treated with the drugs. In CS/H1N1-exposed mice, tiotropium reduced neutrophil and macrophage numbers and levels of interleukin-6 (IL-6) and interferon-γ (IFN-γ) in the airways and improved lung function. In contrast, fluticasone increased the loss of body weight; failed to reduce neutrophil or macrophage numbers; increased IL-6, KC, and tumor necrosis factor-α (TNF-α) in the lungs; and worsened lung function. Treatment with roflumilast reduced macrophage numbers, IL-6, and KC in the lungs but had no effect on neutrophil numbers or lung function. In CS/RSV-exposed mice, treatment with tiotropium, but not fluticasone or roflumilast, reduced neutrophil numbers and IL-6 and TNF-α levels in the lungs. Viral load of H1N1 and RSV was significantly elevated in CS/virus-exposed mice and NCI-H292 cells after fluticasone treatment, whereas tiotropium and roflumilast had no effect. In conclusion, tiotropium has anti-inflammatory effects on CS/virus-induced inflammation in mice that are superior to the effects of roflumilast and fluticasone. This finding might help to explain the observed reduction of exacerbation rates in COPD patients. PMID:27016458

  5. Latitudinal variation in virus-induced mortality of phytoplankton across the North Atlantic Ocean.

    PubMed

    Mojica, Kristina D A; Huisman, Jef; Wilhelm, Steven W; Brussaard, Corina P D

    2016-02-01

    Viral lysis of phytoplankton constrains marine primary production, food web dynamics and biogeochemical cycles in the ocean. Yet, little is known about the biogeographical distribution of viral lysis rates across the global ocean. To address this, we investigated phytoplankton group-specific viral lysis rates along a latitudinal gradient within the North Atlantic Ocean. The data show large-scale distribution patterns of different virus groups across the North Atlantic that are associated with the biogeographical distributions of their potential microbial hosts. Average virus-mediated lysis rates of the picocyanobacteria Prochlorococcus and Synechococcus were lower than those of the picoeukaryotic and nanoeukaryotic phytoplankton (that is, 0.14 per day compared with 0.19 and 0.23 per day, respectively). Total phytoplankton mortality (virus plus grazer-mediated) was comparable to the gross growth rate, demonstrating high turnover rates of phytoplankton populations. Virus-induced mortality was an important loss process at low and mid latitudes, whereas phytoplankton mortality was dominated by microzooplankton grazing at higher latitudes (>56°N). This shift from a viral-lysis-dominated to a grazing-dominated phytoplankton community was associated with a decrease in temperature and salinity, and the decrease in viral lysis rates was also associated with increased vertical mixing at higher latitudes. Ocean-climate models predict that surface warming will lead to an expansion of the stratified and oligotrophic regions of the world's oceans. Our findings suggest that these future shifts in the regional climate of the ocean surface layer are likely to increase the contribution of viral lysis to phytoplankton mortality in the higher-latitude waters of the North Atlantic, which may potentially reduce transfer of matter and energy up the food chain and thus affect the capacity of the northern North Atlantic to act as a long-term sink for CO2.

  6. Latitudinal variation in virus-induced mortality of phytoplankton across the North Atlantic Ocean

    PubMed Central

    Mojica, Kristina D A; Huisman, Jef; Wilhelm, Steven W; Brussaard, Corina P D

    2016-01-01

    Viral lysis of phytoplankton constrains marine primary production, food web dynamics and biogeochemical cycles in the ocean. Yet, little is known about the biogeographical distribution of viral lysis rates across the global ocean. To address this, we investigated phytoplankton group-specific viral lysis rates along a latitudinal gradient within the North Atlantic Ocean. The data show large-scale distribution patterns of different virus groups across the North Atlantic that are associated with the biogeographical distributions of their potential microbial hosts. Average virus-mediated lysis rates of the picocyanobacteria Prochlorococcus and Synechococcus were lower than those of the picoeukaryotic and nanoeukaryotic phytoplankton (that is, 0.14 per day compared with 0.19 and 0.23 per day, respectively). Total phytoplankton mortality (virus plus grazer-mediated) was comparable to the gross growth rate, demonstrating high turnover rates of phytoplankton populations. Virus-induced mortality was an important loss process at low and mid latitudes, whereas phytoplankton mortality was dominated by microzooplankton grazing at higher latitudes (>56°N). This shift from a viral-lysis-dominated to a grazing-dominated phytoplankton community was associated with a decrease in temperature and salinity, and the decrease in viral lysis rates was also associated with increased vertical mixing at higher latitudes. Ocean-climate models predict that surface warming will lead to an expansion of the stratified and oligotrophic regions of the world's oceans. Our findings suggest that these future shifts in the regional climate of the ocean surface layer are likely to increase the contribution of viral lysis to phytoplankton mortality in the higher-latitude waters of the North Atlantic, which may potentially reduce transfer of matter and energy up the food chain and thus affect the capacity of the northern North Atlantic to act as a long-term sink for CO2. PMID:26262815

  7. An efficient virus-induced gene silencing vector for maize functional genomics research.

    PubMed

    Wang, Rong; Yang, Xinxin; Wang, Nian; Liu, Xuedong; Nelson, Richard S; Li, Weimin; Fan, Zaifeng; Zhou, Tao

    2016-04-01

    Maize is a major crop whose rich genetic diversity provides an advanced resource for genetic research. However, a tool for rapid transient gene function analysis in maize that may be utilized in most maize cultivars has been lacking, resulting in reliance on time-consuming stable transformation and mutation studies to obtain answers. We developed an efficient virus-induced gene silencing (VIGS) vector for maize based on a naturally maize-infecting cucumber mosaic virus (CMV) strain, ZMBJ-CMV. An infectious clone of ZMBJ-CMV was constructed, and a vascular puncture inoculation method utilizing Agrobacterium was optimized to improve its utility for CMV infection of maize. ZMBJ-CMV was then modified to function as a VIGS vector. The ZMBJ-CMV vector induced mild to moderate symptoms in many maize lines, making it useful for gene function studies in critically important maize cultivars, such as the sequenced reference inbred line B73. Using this CMV VIGS system, expression of two endogenous genes, ZmPDS and ZmIspH, was found to be decreased by 75% and 78%, respectively, compared with non-silenced tissue. Inserts with lengths of 100-300 bp produced the most complete transcriptional and visual silencing phenotypes. Moreover, genes related to autophagy, ZmATG3 and ZmATG8a, were also silenced, and it was found that they function in leaf starch degradation. These results indicate that our ZMBJ-CMV VIGS vector provides a tool for rapid and efficient gene function studies in maize. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  8. Virus-induced alterations in insulin release in hamster islets of Langerhans.

    PubMed

    Rayfield, E J; Seto, Y; Walsh, S; McEvoy, R C

    1981-11-01

    After the inoculation of Golden Syrian hamsters with the TC-83 vaccine strain of Venezuelan encephalitis (VE) virus, a sustained diminution in glucose-stimulated insulin release and glucose intolerance of shorter duration develops. To understand better the mechanism of this defect in insulin release, we examined insulin secretion in response to several test agents in isolated perifused islets from control and 24-d post-VE virus-infected hamsters. 50 islets were used in all perifusion experiments, and data were expressed as total insulin released as well as peak response for each test agent during a 30-min perifusion period from control and VE-infected islets. After perifusion with 20 mM glucose, a 45% diminution of insulin release was noted in VE-infected islets in comparison with control islets, which in turn was similar to in vivo findings. However, following 1-mM tolbutamide stimulation, insulin release was similar in control and VE-infected islets. In separate studies, 1 mM tolbutamide, 10 mM theophilline, 1 mM dibutyryl cyclic (c)AMP, and 1 mM 8-bromo-cAMP resulted in statistically similar insulin-release curves in control and VE-infected islets. Additional experiments assessing [5-3H]glucose use in control and infected islets after 20 min of perifusion with 20 mM glucose revealed virtually identical values (239 +/- 30-control; and 222 +/- 27-VE-infected islets). Morphological and morphometric evaluation of VE-infected islets (21 d following virus inoculation) showed no changes in islet volume density, beta cell density, and beta cell granulation. Thus, VE virus induces a defect in glucose-stimulated insulin release from hamster beta cells that can be corrected by cAMP analogues and does not alter islet glucose use.

  9. Efficient virus-induced gene silencing in plants using a modified geminivirus DNA1 component.

    PubMed

    Huang, Changjun; Xie, Yan; Zhou, Xueping

    2009-04-01

    Virus-induced gene silencing (VIGS) is currently recognized as a powerful reverse genetics tool for application in functional genomics. DNA1, a satellite-like and single-stranded DNA molecule associated with begomoviruses (Family Geminiviridae), has been shown to replicate autonomously but requires the helper virus for its dissemination. We developed a VIGS vector based on the DNA1 component of tobacco curly shoot virus (TbCSV), a monopartite begomovirus, by inserting a multiple cloning site between the replication-associated protein open reading frame and the A-rich region for subsequent insertion of DNA fragments of genes targeted for silencing. When a host gene (sulphur, Su) or transgene (green fluorescent protein, GFP) was inserted into the modified DNA1 vector and co-agroinoculated with TbCSV, efficient silencing of the cognate gene was observed in Nicotiana benthamiana plants. More interestingly, we demonstrated that this modified DNA1 could effectively suppress GFP in transgenic N. benthamiana or endogenous Su in tobacco plants when co-agroinoculated with tomato yellow leaf curl China virus (TYLCCNV), another monopartite begomovirus that does not induce any viral symptoms. A gene-silencing system in Nicotiana spp., Solanum lycopersicum and Petunia hybrida plants was then established using TYLCCNV and the modified DNA1 vector. The system can be used to silence genes involved in meristem and flower development. The modified DNA1 vector was used to silence the AtTOM homologous genes (NbTOM1 and NbTOM3) in N. benthamiana. Silencing of NbTOM1 or NbTOM3 can reduce tobamovirus multiplication to a lower level, and silencing of both genes simultaneously can completely inhibit tobamovirus multiplication. Previous studies have reported that DNA1 is associated with both monopartite and bipartite begomoviruses, as well as curtoviruses. This vector system can therefore be applied for the study, analysis and discovery of gene function in a variety of important crop plants.

  10. Systematic knockdown of morphine pathway enzymes in opium poppy using virus-induced gene silencing.

    PubMed

    Wijekoon, Champa P; Facchini, Peter J

    2012-03-01

    Opium poppy (Papaver somniferum) remains the sole commercial source for several pharmaceutical alkaloids including the narcotic analgesics codeine and morphine, and the semi-synthetic drugs oxycodone, buprenorphine and naltrexone. Although most of the biosynthetic genes have been identified, the post-transcriptional regulation of the morphinan alkaloid pathway has not been determined. We have used virus-induced gene silencing (VIGS) as a functional genomics tool to investigate the regulation of morphine biosynthesis via a systematic reduction in enzyme levels responsible for the final six steps in the pathway. Specific gene silencing was confirmed at the transcript level by real-time quantitative PCR (polymerase chain reaction), and at the protein level by immunoblot analysis using antibodies raised against salutaridine synthase (SalSyn), salutaridine reductase (SalR), salutaridine 7-O-acetyltransferase (SalAT), thebaine 6-O-demethylase (T6ODM), codeinone reductase (COR), and codeine O-demethylase (CODM). In some cases, silencing a specific biosynthetic gene resulted in a predictable accumulation of the substrate for the corresponding enzyme. Reduced SalSyn, SalR, T6ODM and CODM protein levels correlated with lower morphine levels and a substantial increase in the accumulation of reticuline, salutaridine, thebaine and codeine, respectively. In contrast, the silencing of genes encoding SalAT and COR resulted in the accumulation of salutaridine and reticuline, respectively, which are not the corresponding enzymatic substrates. The silencing of alkaloid biosynthetic genes using VIGS confirms the physiological function of enzymes previously characterized in vitro, provides insight into the biochemical regulation of morphine biosynthesis, and demonstrates the immense potential for metabolic engineering in opium poppy.

  11. Canine distemper virus induces apoptosis in cervical tumor derived cell lines.

    PubMed

    Del Puerto, Helen L; Martins, Almir S; Milsted, Amy; Souza-Fagundes, Elaine M; Braz, Gissandra F; Hissa, Barbara; Andrade, Luciana O; Alves, Fabiana; Rajão, Daniela S; Leite, Rômulo C; Vasconcelos, Anilton C

    2011-06-30

    Apoptosis can be induced or inhibited by viral proteins, it can form part of the host defense against virus infection, or it can be a mechanism for viral spread to neighboring cells. Canine distemper virus (CDV) induces apoptotic cells in lymphoid tissues and in the cerebellum of dogs naturally infected. CDV also produces a cytopathologic effect, leading to apoptosis in Vero cells in tissue culture. We tested canine distemper virus, a member of the Paramyxoviridae family, for the ability to trigger apoptosis in HeLa cells, derived from cervical cancer cells resistant to apoptosis. To study the effect of CDV infection in HeLa cells, we examined apoptotic markers 24 h post infection (pi), by flow cytometry assay for DNA fragmentation, real-time PCR assay for caspase-3 and caspase-8 mRNA expression, and by caspase-3 and -8 immunocytochemistry. Flow cytometry showed that DNA fragmentation was induced in HeLa cells infected by CDV, and immunocytochemistry revealed a significant increase in the levels of the cleaved active form of caspase-3 protein, but did not show any difference in expression of caspase-8, indicating an intrinsic apoptotic pathway. Confirming this observation, expression of caspase-3 mRNA was higher in CDV infected HeLa cells than control cells; however, there was no statistically significant change in caspase-8 mRNA expression profile. Our data suggest that canine distemper virus induced apoptosis in HeLa cells, triggering apoptosis by the intrinsic pathway, with no participation of the initiator caspase -8 from the extrinsic pathway. In conclusion, the cellular stress caused by CDV infection of HeLa cells, leading to apoptosis, can be used as a tool in future research for cervical cancer treatment and control.

  12. Optimizing virus-induced gene silencing efficiency with Cymbidium mosaic virus in Phalaenopsis flower.

    PubMed

    Hsieh, Ming-Hsien; Lu, Hsiang-Chia; Pan, Zhao-Jun; Yeh, Hsin-Hung; Wang, Shyh-Shyan; Chen, Wen-Huei; Chen, Hong-Hwa

    2013-03-01

    Virus-induced gene silencing (VIGS) is a good way to study floral gene functions of orchids, especially those with a long life cycle. To explore the applicability and improve viral silencing efficiency for application of Cymbidium mosaic virus (CymMV)-induced gene silencing, we examined several variables, including the optimal length of the DNA fragment, the effect of developmental maturation status of inflorescence, and suitable inoculation sites. A CymMV-based VIGS system can be used with orchids to silence genes including PeUFGT3, PeMADS5 and PeMADS6 and induce prominent phenotypes with silencing efficiency up to 95.8% reduction. The DNA fragment size used for silencing can be as small as 78-85 bp and still reach 61.5-95.8% reduction. The effect of cDNA location as a target in VIGS varies among genes because of non-target gene influence when using the 5' terminus of the coding region of both PeMADS5 and PeMADS6. Use of VIGS to knock down a B-class MADS-box gene (PeMADS6) in orchids with different maturation status of inflorescence allowed for observing discernable knockdown phenotypes in flowers. Furthermore, silencing effects with Agro-infiltration did not differ with both leaf and inflorescence injections, but injection in the leaf saved time and produced less damage to plants. We propose an optimized approach for VIGS using CymMV as a silencing vector for floral functional genomics in Phalaenopsis orchid with Agro-infiltration: (1) DNA fragment length about 80 bp, (2) a more mature status of inflorescence and (3) leaf injection.

  13. Functional genomic analysis of cotton genes with agrobacterium-mediated virus-induced gene silencing.

    PubMed

    Gao, Xiquan; Shan, Libo

    2013-01-01

    Cotton (Gossypium spp.) is one of the most agronomically important crops worldwide for its unique textile fiber production and serving as food and feed stock. Molecular breeding and genetic engineering of useful genes into cotton have emerged as advanced approaches to improve cotton yield, fiber quality, and resistance to various stresses. However, the understanding of gene functions and regulations in cotton is largely hindered by the limited molecular and biochemical tools. Here, we describe the method of an Agrobacterium infiltration-based virus-induced gene silencing (VIGS) assay to transiently silence endogenous genes in cotton at 2-week-old seedling stage. The genes of interest could be readily silenced with a consistently high efficiency. To monitor gene silencing efficiency, we have cloned cotton GrCla1 from G. raimondii, a homolog gene of Arabidopsis Cloroplastos alterados 1 (AtCla1) involved in chloroplast development, and inserted into a tobacco rattle virus (TRV) binary vector pYL156. Silencing of GrCla1 results in albino phenotype on the newly emerging leaves, serving as a visual marker for silencing efficiency. To further explore the possibility of using VIGS assay to reveal the essential genes mediating disease resistance to Verticillium dahliae, a fungal pathogen causing severe Verticillium wilt in cotton, we developed a seedling infection assay to inoculate cotton seedlings when the genes of interest are silenced by VIGS. The method we describe here could be further explored for functional genomic analysis of cotton genes involved in development and various biotic and abiotic stresses.

  14. Genetics Home Reference: chronic myeloid leukemia

    MedlinePlus

    ... Home Health Conditions chronic myeloid leukemia chronic myeloid leukemia Printable PDF Open All Close All Enable Javascript ... view the expand/collapse boxes. Description Chronic myeloid leukemia is a slow-growing cancer of the blood- ...

  15. Treating Chronic Myeloid Leukemia by Phase

    MedlinePlus

    ... Myeloid Leukemia Targeted Therapies for Chronic Myeloid Leukemia Interferon Therapy for Chronic Myeloid Leukemia Chemotherapy for Chronic ... to help decide what drug would be best. Interferon or chemotherapy (chemo) may be tried for those ...

  16. Gemtuzumab Ozogamicin in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia or Acute Promyelocytic Leukemia

    ClinicalTrials.gov

    2017-02-20

    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); Childhood Acute Promyelocytic Leukemia (M3); Recurrent Adult Acute Myeloid Leukemia; Recurrent Childhood Acute Myeloid Leukemia

  17. Targeted therapy: The new lease on life for acute promyelocytic leukemia, and beyond.

    PubMed

    Chen, Sai-Juan; Zhou, Guang-Biao

    2012-08-01

    Leukemia, a group of hematological malignancies characterized by abnormal proliferation, decreased apoptosis, and blocked differentiation of hematopoietic stem/progenitor cells, is a disease involving dynamic change in the genome. Chromosomal translocation and point mutation are the major mechanisms in leukemia, which lead to production of oncogenes with dominant gain of function and tumor suppressor genes with recessive loss of function. Targeted therapy refers to treatment strategies perturbing the molecules critical for leukemia pathogenesis. The t(15;17) which generates PML-RARα, t(8;21) that produces AML1-ETO, and t(9;22) which generates BCR-ABL are the three most frequently seen chromosomal translocations in myeloid leukemia. The past two to three decades have witnessed tremendous success in development of targeted therapies for acute and chronic myeloid leukemia caused by the three fusion proteins. Here, we review the therapeutic efficacies and the mechanisms of action of targeted therapies for myeloid leukemia and show how this strategy significantly improve the clinical outcome of patients and even turn acute promyelocytic leukemia from highly fatal to highly curable.

  18. MS-275 and Azacitidine in Treating Patients With Myelodysplastic Syndromes, Chronic Myelomonocytic Leukemia, or Acute Myeloid Leukemia

    ClinicalTrials.gov

    2017-01-31

    Chronic Myelomonocytic Leukemia; de Novo Myelodysplastic Syndrome; Leukemia; Previously Treated Myelodysplastic Syndrome; Recurrent Adult Acute Myeloid Leukemia; Secondary Acute Myeloid Leukemia; Secondary Myelodysplastic Syndrome; Untreated Adult Acute Myeloid Leukemia

  19. Differential requirement for wild-type Flt3 in leukemia initiation among mouse models of human leukemia.

    PubMed

    Kamezaki, Kenjiro; Luchsinger, Larry L; Snoeck, Hans-Willem

    2014-03-01

    FLT3 is one of the most frequently mutated genes in acute leukemias. However, the role in leukemogenesis of wild-type (wt) FLT3, which is highly expressed in many hematologic malignancies, is unclear. We show here that in mouse models established by retroviral transduction of leukemic fusion proteins, deletion of Flt3 strongly inhibits MLL-ENL and to lesser extent p210(BCR-ABL)-induced leukemogenesis, but has no effect in MLL-AF9 or AML1-ETO9a models. Flt3 acts at the level of leukemic stem cells (LSCs), as a fraction of LSCs in MLL-ENL, but not in MLL-AF9-induced leukemia, expressed Flt3 in vivo, and Flt3 expression on LSCs was associated with leukemia development in this model. Furthermore, efficiency of MLL-ENL, but not of MLL-AF9-induced leukemia induction was significantly enhanced after transduction of Flt3(+) compared to Flt3(-) wt myeloid progenitors. However, Flt3 is not required for immortalization of bone marrow cells in vitro by MLL-ENL and does not affect colony formation by MLL-ENL LSCs in vitro, suggesting that in vitro models do not reflect the in vivo biology of MLL-ENL leukemia with respect to Flt3 requirement. We conclude that wt Flt3 plays a role in leukemia initiation in vivo, which is, however, not universal. Copyright © 2014 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.

  20. Phase I Dose-Escalation Trial of Clofarabine Followed by Escalating Doses of Fractionated Cyclophosphamide in Children With Relapsed or Refractory Acute Leukemias

    ClinicalTrials.gov

    2010-09-21

    Myelodysplastic Syndrome; Acute Myeloid Leukemia; Myeloproliferative Disorders; Acute Lymphocytic Leukemia; Acute Promyelocytic Leukemia; Acute Leukemia; Chronic Myelogenous Leukemia; Myelofibrosis; Chronic Myelomonocytic Leukemia; Juvenile Myelomonocytic Leukemia

  1. Temsirolimus and Imatinib Mesylate in Treating Patients With Chronic Myelogenous Leukemia

    ClinicalTrials.gov

    2013-01-11

    Accelerated Phase Chronic Myelogenous Leukemia; Blastic Phase Chronic Myelogenous Leukemia; Chronic Myelogenous Leukemia, BCR-ABL1 Positive; Chronic Phase Chronic Myelogenous Leukemia; Relapsing Chronic Myelogenous Leukemia

  2. Imatinib Mesylate and Decitabine in Treating Patients With Chronic Myelogenous Leukemia

    ClinicalTrials.gov

    2013-01-22

    Accelerated Phase Chronic Myelogenous Leukemia; Blastic Phase Chronic Myelogenous Leukemia; Childhood Chronic Myelogenous Leukemia; Chronic Myelogenous Leukemia, BCR-ABL1 Positive; Relapsing Chronic Myelogenous Leukemia

  3. Newly Diagnosed Acute Promyelocytic Leukemia

    PubMed Central

    Avvisati, Giuseppe

    2011-01-01

    Acute promyelocytic leukemia (APL) represents a medical emergency with a high rate of early mortality. As a consequence, as soon as the diagnosis is suspected based upon cytologic criteria, it is necessary to start all- trans retinoic acid (ATRA) treatment without delay. For patients with newly diagnosed APL, induction therapy with ATRA plus anthracycline based chemotherapy is recommended. At present the combination of arsenic trioxide plus ATRA should be considered for patients who are not candidates for anthracycline-based therapy. For pediatric and adult patients with APL aged < 60 years who achieve a CR with induction, I recommend 3 intensive courses of consolidation chemotherapy associated to ATRA, targeted on the basis of the risk group at diagnosis. In patients treated with a very intensive consolidation chemotherapy maintenance treatment can be omitted. However If a maintenance treatment has to be adopted I suggest the use of intermittent ATRA for 15 days every 3 months for a period of 2 years, rather than ATRA associated to chemotherapy. Moreover, taking into account the medical literature, a reduced dosage of ATRA ( 25 mg/m2) in pediatric patients and a consolidation chemotherapy of reduced intensity in elderly patients is recommended. Furthermore, in order to maximize survival, careful attention should be reserved to the coagulopathy and to the appearance of the differentiation syndrome. Finally, PCR for the PML/RARA fusion gene on a bone marrow specimen every three months for two years, and then every six months for additional three years are needed during the follow-up. PMID:22220261

  4. Comprehensive mutational analysis of primary and relapse acute promyelocytic leukemia

    PubMed Central

    Madan, V; Shyamsunder, P; Han, L; Mayakonda, A; Nagata, Y; Sundaresan, J; Kanojia, D; Yoshida, K; Ganesan, S; Hattori, N; Fulton, N; Tan, K-T; Alpermann, T; Kuo, M-C; Rostami, S; Matthews, J; Sanada, M; Liu, L-Z; Shiraishi, Y; Miyano, S; Chendamarai, E; Hou, H-A; Malnassy, G; Ma, T; Garg, M; Ding, L-W; Sun, Q-Y; Chien, W; Ikezoe, T; Lill, M; Biondi, A; Larson, R A; Powell, B L; Lübbert, M; Chng, W J; Tien, H-F; Heuser, M; Ganser, A; Koren-Michowitz, M; Kornblau, S M; Kantarjian, H M; Nowak, D; Hofmann, W-K; Yang, H; Stock, W; Ghavamzadeh, A; Alimoghaddam, K; Haferlach, T; Ogawa, S; Shih, L-Y; Mathews, V; Koeffler, H P

    2016-01-01

    Acute promyelocytic leukemia (APL) is a subtype of myeloid leukemia characterized by differentiation block at the promyelocyte stage. Besides the presence of chromosomal rearrangement t(15;17), leading to the formation of PML-RARA (promyelocytic leukemia-retinoic acid receptor alpha) fusion, other genetic alterations have also been implicated in APL. Here, we performed comprehensive mutational analysis of primary and relapse APL to identify somatic alterations, which cooperate with PML-RARA in the pathogenesis of APL. We explored the mutational landscape using whole-exome (n=12) and subsequent targeted sequencing of 398 genes in 153 primary and 69 relapse APL. Both primary and relapse APL harbored an average of eight non-silent somatic mutations per exome. We observed recurrent alterations of FLT3, WT1, NRAS and KRAS in the newly diagnosed APL, whereas mutations in other genes commonly mutated in myeloid leukemia were rarely detected. The molecular signature of APL relapse was characterized by emergence of frequent mutations in PML and RARA genes. Our sequencing data also demonstrates incidence of loss-of-function mutations in previously unidentified genes, ARID1B and ARID1A, both of which encode for key components of the SWI/SNF complex. We show that knockdown of ARID1B in APL cell line, NB4, results in large-scale activation of gene expression and reduced in vitro differentiation potential. PMID:27063598

  5. Fusion energy

    NASA Astrophysics Data System (ADS)

    1990-09-01

    The main purpose of the International Thermonuclear Experimental Reactor (ITER) is to develop an experimental fusion reactor through the united efforts of many technologically advanced countries. The ITER terms of reference, issued jointly by the European Community, Japan, the USSR, and the United States, call for an integrated international design activity and constitute the basis of current activities. Joint work on ITER is carried out under the auspices of the International Atomic Energy Agency (IAEA), according to the terms of quadripartite agreement reached between the European Community, Japan, the USSR, and the United States. The site for joint technical work sessions is at the Max Planck Institute of Plasma Physics. Garching, Federal Republic of Germany. The ITER activities have two phases: a definition phase performed in 1988 and the present design phase (1989 to 1990). During the definition phase, a set of ITER technical characteristics and supporting research and development (R and D) activities were developed and reported. The present conceptual design phase of ITER lasts until the end of 1990. The objectives of this phase are to develop the design of ITER, perform a safety and environmental analysis, develop site requirements, define future R and D needs, and estimate cost, manpower, and schedule for construction and operation. A final report will be submitted at the end of 1990. This paper summarizes progress in the ITER program during the 1989 design phase.

  6. Fusion energy

    SciTech Connect

    Not Available

    1990-09-01

    The main purpose of the International Thermonuclear Experimental Reactor (ITER) is to develop an experimental fusion reactor through the united efforts of many technologically advanced countries. The ITER terms of reference, issued jointly by the European Community, Japan, the USSR, and the United States, call for an integrated international design activity and constitute the basis of current activities. Joint work on ITER is carried out under the auspices of the International Atomic Energy Agency (IAEA), according to the terms of quadripartite agreement reached between the European Community, Japan, the USSR, and the United States. The site for joint technical work sessions is at the MaxPlanck Institute of Plasma Physics. Garching, Federal Republic of Germany. The ITER activities have two phases: a definition phase performed in 1988 and the present design phase (1989--1990). During the definition phase, a set of ITER technical characteristics and supporting research and development (R D) activities were developed and reported. The present conceptual design phase of ITER lasts until the end of 1990. The objectives of this phase are to develop the design of ITER, perform a safety and environmental analysis, develop site requirements, define future R D needs, and estimate cost, manpower, and schedule for construction and operation. A final report will be submitted at the end of 1990. This paper summarizes progress in the ITER program during the 1989 design phase.

  7. Donor cell leukemia.

    PubMed

    Ruiz-Arguelles, Alejandro

    2012-04-01

    Minimal residual disease refers to the tumour cells that are still present in a given patient after completion of a therapeutic scheme. The demonstration and quantification of residual neoplastic cells has a crucial impact in clinical decision making, for it might prompt continuation of treatment, while the absence of such cells might serve as evidence to withdraw therapy. Therefore, both sensitivity and specificity of the methods used to unravel residual neoplastic cells must be highly reliable and robust. Flow cytometry has been widely used for this purpose, and its clinical performance depends mainly on the criteria of interpretation, rather than in the technique by itself; molecular biology techniques have proved to be highly sensitive and specific but unfortunately they cannot be used in all patients or in all types of leukemia. Finally, the development of donor cell leukemia in transplanted patients, might mimic residual disease and add more confusion to an already controversial issue. These topics are discussed in this paper.

  8. Mast cell leukemia.

    PubMed

    Georgin-Lavialle, Sophie; Lhermitte, Ludovic; Dubreuil, Patrice; Chandesris, Marie-Olivia; Hermine, Olivier; Damaj, Gandhi

    2013-02-21

    Mast cell leukemia (MCL) is a very rare form of aggressive systemic mastocytosis accounting for < 1% of all mastocytosis. It may appear de novo or secondary to previous mastocytosis and shares more clinicopathologic aspects with systemic mastocytosis than with acute myeloid leukemia. Symptoms of mast cell activation-involvement of the liver, spleen, peritoneum, bones, and marrow-are frequent. Diagnosis is based on the presence of ≥ 20% atypical mast cells in the marrow or ≥ 10% in the blood; however, an aleukemic variant is frequently encountered in which the number of circulating mast cells is < 10%. The common phenotypic features of pathologic mast cells encountered in most forms of mastocytosis are unreliable in MCL. Unexpectedly, non-KIT D816V mutations are frequent and therefore, complete gene sequencing is necessary. Therapy usually fails and the median survival time is < 6 months. The role of combination therapies and bone marrow transplantation needs further investigation.

  9. IMMUNOTHERAPY IN ACUTE LEUKEMIA

    PubMed Central

    Leung, Wing

    2010-01-01

    Recent advances in immunotherapy of cancer may represent a successful example in translational research, in which progress in knowledge and technology in immunology has lead to new strategies of immunotherapy, and even past failure in many clinical trials have led to a better understanding of basic cancer immunobiology. This article reviews the latest concepts in antitumor immunology and its application in the treatment of cancer, with particular focus on acute leukemia. PMID:19100371

  10. Phase 1 Study of Terameprocol (EM-1421) in Patients With Leukemia

    ClinicalTrials.gov

    2016-02-20

    Leukemias; Acute Myeloid Leukemia (AML); Acute Lymphocytic Leukemia (ALL); Adult T Cell Leukemia (ATL); Chronic Myeloid Leukemia (CML-BP); Chronic Lymphocytic Leukemia (CLL); Myelodysplastic Syndrome (MDS); Chronic Myelomonocytic Leukemia (CMML)

  11. Targeting of a Nuclease to Murine Leukemia Virus Capsids Inhibits Viral Multiplication

    NASA Astrophysics Data System (ADS)

    Natsoulis, Georges; Seshaiah, Partha; Federspiel, Mark J.; Rein, Alan; Hughes, Stephen H.; Boeke, Jef D.

    1995-01-01

    Capsid-targeted viral inactivation is an antiviral strategy in which toxic fusion proteins are targeted to virions, where they inhibit viral multiplication by destroying viral components. These fusion proteins consist of a virion structural protein moiety and an enzymatic moiety such as a nuclease. Such fusion proteins can severely inhibit transposition of yeast retrotransposon Ty1, an element whose transposition mechanistically resembles retroviral multiplication. We demonstrate that expression of a murine retrovirus capsid-staphylococcal nuclease fusion protein inhibits multiplication of the corresponding murine leukemia virus by 30- to 100-fold. Staphylococcal nuclease is apparently inactive intracellularly and hence nontoxic to the host cell, but it is active extracellularly because of its requirement for high concentrations of Ca2+ ions. Virions assembled in and shed from cells expressing the fusion protein contain very small amounts of intact viral RNA, as would be predicted for nuclease-mediated inhibition of viral multiplication.

  12. SB-715992 in Treating Patients With Acute Leukemia, Chronic Myelogenous Leukemia, or Advanced Myelodysplastic Syndromes

    ClinicalTrials.gov

    2013-01-10

    Acute Undifferentiated 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(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); Adult Erythroleukemia (M6a); Adult Pure Erythroid Leukemia (M6b); Blastic Phase Chronic Myelogenous Leukemia; de Novo Myelodysplastic Syndromes; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Refractory Anemia With Excess Blasts; Refractory Anemia With Excess Blasts in Transformation; Relapsing Chronic Myelogenous Leukemia; Secondary Acute Myeloid Leukemia; Secondary Myelodysplastic Syndromes; Untreated Adult Acute Myeloid Leukemia

  13. The fusogenic state of Mayaro virus induced by low pH and by hydrostatic pressure.

    PubMed

    Freitas, Monica; Da Poian, Andrea T; Barth, Ortrud M; Rebello, Moacyr A; Silva, Jerson L; Gaspar, Luciane P

    2006-01-01

    Mayaro virus is an enveloped virus that belongs to the Alphavirus genus. To gain insight into the mechanism involved in Mayaro virus membrane fusion, we used hydrostatic pressure and low pH to isolate a fusion-active state of Mayaro glycoproteins. In response to pressure, E1 glycoprotein undergoes structural changes resulting in the formation of a stable conformation. This state was characterized and correlated to that induced by low pH as measured by intrinsic fluorescence, 4,4'-dianilino-1,1'-binaphthyl-5,5'-disulfonic acid, dipotassium salt fluorescence, fluorescence resonance energy transfer, electron microscopy, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In parallel, we used a neutralization assay to show that Mayaro virus in the fusogenic state retained most of the original immunogenic properties and could elicit high titers of neutralizing antibodies.

  14. Retinoid receptor signaling and autophagy in acute promyelocytic leukemia

    SciTech Connect

    Orfali, Nina; McKenna, Sharon L.; Cahill, Mary R.; Gudas, Lorraine J.; Mongan, Nigel P.

    2014-05-15

    Retinoids are a family of signaling molecules derived from vitamin A with well established roles in cellular differentiation. Physiologically active retinoids mediate transcriptional effects on cells through interactions with retinoic acid (RARs) and retinoid-X (RXR) receptors. Chromosomal translocations involving the RARα gene, which lead to impaired retinoid signaling, are implicated in acute promyelocytic leukemia (APL). All-trans-retinoic acid (ATRA), alone and in combination with arsenic trioxide (ATO), restores differentiation in APL cells and promotes degradation of the abnormal oncogenic fusion protein through several proteolytic mechanisms. RARα fusion-protein elimination is emerging as critical to obtaining sustained remission and long-term cure in APL. Autophagy is a degradative cellular pathway involved in protein turnover. Both ATRA and ATO also induce autophagy in APL cells. Enhancing autophagy may therefore be of therapeutic benefit in resistant APL and could broaden the application of differentiation therapy to other cancers. Here we discuss retinoid signaling in hematopoiesis, leukemogenesis, and APL treatment. We highlight autophagy as a potential important regulator in anti-leukemic strategies. - Highlights: • Normal and aberrant retinoid signaling in hematopoiesis and leukemia is reviewed. • We suggest a novel role for RARα in the development of X-RARα gene fusions in APL. • ATRA therapy in APL activates transcription and promotes onco-protein degradation. • Autophagy may be involved in both onco-protein degradation and differentiation. • Pharmacologic autophagy induction may potentiate ATRA's therapeutic effects.

  15. New insights into transcriptional and leukemogenic mechanisms of AML1-ETO and E2A fusion proteins

    PubMed Central

    Li, Jian; Guo, Chun; Steinauer, Nickolas; Zhang, Jinsong

    2016-01-01

    BACKGROUND Nearly 15% of acute myeloid leukemia (AML) cases are caused by aberrant expression of AML1-ETO, a fusion protein generated by the t(8;21) chromosomal translocation. Since its discovery, AML1-ETO has served as a prototype to understand how leukemia fusion proteins deregulate transcription to promote leukemogenesis. Another leukemia fusion protein, E2A-Pbx1, generated by the t(1;19) translocation, is involved in acute lymphoblastic leukemias (ALLs). While AML1-ETO and E2A-Pbx1 are structurally unrelated fusion proteins, we have recently shown that a common axis, the ETO/E-protein interaction, is involved in the regulation of both fusion proteins, underscoring the importance of studying protein–protein interactions in elucidating the mechanisms of leukemia fusion proteins. OBJECTIVE In this review, we aim to summarize these new developments while also providing a historic overview of the related early studies. METHODS A total of 218 publications were reviewed in this article, a majority of which were published after 2004.We also downloaded 3D structures of AML1-ETO domains from Protein Data Bank and provided a systematic summary of their structures. RESULTS By reviewing the literature, we summarized early and recent findings on AML1-ETO, including its protein–protein interactions, transcriptional and leukemogenic mechanisms, as well as the recently reported involvement of ETO family corepressors in regulating the function of E2A-Pbx1. CONCLUSION While the recent development in genomic and structural studies has clearly demonstrated that the fusion proteins function by directly regulating transcription, a further understanding of the underlying mechanisms, including crosstalk with other transcription factors and cofactors, and the protein–protein interactions in the context of native proteins, may be necessary for the development of highly targeted drugs for leukemia therapy. PMID:28261265

  16. [Chronic myeloid leukemia: "archetype" of the impact of targeted therapies].

    PubMed

    Nasr, R; Bazarbachi, A

    2012-08-01

    Chronic myeloid leukemia (CML) is a chronic blood disorder characterized by a reciprocal translocation between chromosomes 9 and 22, leading to the creation of a chimeric gene encoding the BCR-ABL fusion protein with a constitutive tyrosine kinase activity. Although long known as a disease with an inexorable progression to acute leukemia, CML history has been significantly improved by the use of imatinib, a tyrosine kinase inhibitor. Imatinib has revolutionized the treatment of CML by transforming it from an invariably fatal disease to a chronic but manageable condition. In fact, the discovery of this class of targeted therapy had an impact not only on the survival of CML patients but also on other scientific and medical fields. This review illustrates the impact of imatinib, the first example of tyrosine kinase inhibitors on the treatment of CML, on the treatment of other cancers, the impact on health systems and on the scientific research in general.

  17. Agrobacterium-mediated virus-induced gene silencing assay in cotton.

    PubMed

    Gao, Xiquan; Britt, Robert C; Shan, Libo; He, Ping

    2011-08-20

    Cotton (Gossypium hirsutum) is one of the most important crops worldwide. Considerable efforts have been made on molecular breeding of new varieties. The large-scale gene functional analysis in cotton has been lagged behind most of the modern plant species, likely due to its large size of genome, gene duplication and polyploidy, long growth cycle and recalcitrance to genetic transformation(1). To facilitate high throughput functional genetic/genomic study in cotton, we attempt to develop rapid and efficient transient assays to assess cotton gene functions. Virus-Induced Gene Silencing (VIGS) is a powerful technique that was developed based on the host Post-Transcriptional Gene Silencing (PTGS) to repress viral proliferation(2,3). Agrobacterium-mediated VIGS has been successfully applied in a wide range of dicots species such as Solanaceae, Arabidopsis and legume species, and monocots species including barley, wheat and maize, for various functional genomic studies(3,4). As this rapid and efficient approach avoids plant transformation and overcomes functional redundancy, it is particularly attractive and suitable for functional genomic study in crop species like cotton not amenable for transformation. In this study, we report the detailed protocol of Agrobacterium-mediated VIGS system in cotton. Among the several viral VIGS vectors, the tobacco rattle virus (TRV) invades a wide range of hosts and is able to spread vigorously throughout the entire plant yet produce mild symptoms on the hosts5. To monitor the silencing efficiency, GrCLA1, a homolog gene of Arabidopsis Cloroplastos alterados 1 gene (AtCLA1) in cotton, has been cloned and inserted into the VIGS binary vector pYL156. CLA1 gene is involved in chloroplast development(6), and previous studies have shown that loss-of-function of AtCLA1 resulted in an albino phenotype on true leaves(7), providing an excellent visual marker for silencing efficiency. At approximately two weeks post Agrobacterium infiltration

  18. High rates of virus-induced gene silencing by tobacco rattle virus in Populus.

    PubMed

    Shen, Zedan; Sun, Jian; Yao, Jun; Wang, Shaojie; Ding, Mingquan; Zhang, Huilong; Qian, Zeyong; Zhao, Nan; Sa, Gang; Zhao, Rui; Shen, Xin; Polle, Andrea; Chen, Shaoliang

    2015-09-01

    Virus-induced gene silencing (VIGS) has been shown to be an effective tool for investigating gene functions in herbaceous plant species, but has rarely been tested in trees. The establishment of a fast and reliable transformation system is especially important for woody plants, many of which are recalcitrant to transformation. In this study, we established a tobacco rattle virus (TRV)-based VIGS system for two Populus species, Populus euphratica and P. × canescens. Here, TRV constructs carrying a 266 bp or a 558 bp fragment of the phytoene desaturase (PDS) gene were Agrobacterium-infiltrated into leaves of the two poplar species. Agrobacterium-mediated delivery of the shorter insert, TRV2-PePDS266, into the host poplars resulted in expected photobleaching in both tree species, but not the longer insert, PePDS558. The efficiency of VIGS was temperature-dependent, increasing by raising the temperature from 18 to 28 °C. The optimized TRV-VIGS system at 28 °C resulted in a high silencing frequency and efficiency up to 65-73 and 83-94%, respectively, in the two tested poplars. Moreover, syringe inoculation of Agrobacterium in 100 mM acetosyringone induced a more efficient silencing in the two poplar species, compared with other agroinfiltration methods, e.g., direct injection, misting and agrodrench. There were plant species-related differences in the response to VIGS because the photobleaching symptoms were more severe in P. × canescens than in P. euphratica. Furthermore, VIGS-treated P. euphratica exhibited a higher recovery rate (50%) after several weeks of the virus infection, compared with TRV-infected P. × canescens plants (20%). Expression stability of reference genes was screened to assess the relative abundance of PePDS mRNA in VIGS-treated P. euphratica and P. × canescens. PeACT7 was stably expressed in P. euphratica and UBQ-L was selected as the most suitable reference gene for P. × canescens using three different

  19. Highly efficient virus-induced gene silencing in apple and soybean by apple latent spherical virus vector and biolistic inoculation.

    PubMed

    Yamagishi, Noriko; Yoshikawa, Nobuyuki

    2013-01-01

    Virus-induced gene silencing (VIGS) is an effective tool for the analysis of the gene function in plants within a short time. However, in woody fruit tree like apple, some of Solanum crops, and soybean, it is generally difficult to inoculate virus vector by conventional inoculation methods. Here, we show efficient VIGS in apple and soybean by Apple latent spherical virus (ALSV) vector and biolistic inoculation. The plants inoculated with ALSV vectors by particle bombardment showed uniform silenced phenotypes of target genes within 2-3 weeks post inoculation.

  20. Childhood Leukemia and Primary Prevention

    PubMed Central

    Whitehead, Todd P.; Metayer, Catherine; Wiemels, Joseph L.; Singer, Amanda W.; Miller, Mark D.

    2016-01-01

    Leukemia is the most common pediatric cancer, affecting 3,800 children per year in the United States. Its annual incidence has increased over the last decades, especially among Latinos. Although most children diagnosed with leukemia are now cured, many suffer long-term complications, and primary prevention efforts are urgently needed. The early onset of leukemia – usually before age five – and the presence at birth of “pre-leukemic” genetic signatures indicate that pre- and postnatal events are critical to the development of the disease. In contrast to most pediatric cancers, there is a growing body of literature – in the United States and internationally – that has implicated several environmental, infectious, and dietary risk factors in the etiology of childhood leukemia, mainly for acute lymphoblastic leukemia, the most common subtype. For example, exposures to pesticides, tobacco smoke, solvents, and traffic emissions have consistently demonstrated positive associations with the risk of developing childhood leukemia. In contrast, intake of vitamins and folate supplementation during the pre-conception period or pregnancy, breastfeeding, and exposure to routine childhood infections have been shown to reduce the risk of childhood leukemia. Some children may be especially vulnerable to these risk factors, as demonstrated by a disproportionate burden of childhood leukemia in the Latino population of California. The evidence supporting the associations between childhood leukemia and its risk factors – including pooled analyses from around the world and systematic reviews – is strong; however, the dissemination of this knowledge to clinicians has been limited. To protect children’s health, it is prudent to initiate programs designed to alter exposure to well-established leukemia risk factors rather than to suspend judgement until no uncertainty remains. Primary prevention programs for childhood leukemia would also result in the significant co

  1. ZFX controls propagation and prevents differentiation of acute T-lymphoblastic and myeloid leukemia.

    PubMed

    Weisberg, Stuart P; Smith-Raska, Matthew R; Esquilin, Jose M; Zhang, Ji; Arenzana, Teresita L; Lau, Colleen M; Churchill, Michael; Pan, Haiyan; Klinakis, Apostolos; Dixon, Jack E; Mirny, Leonid A; Mukherjee, Siddhartha; Reizis, Boris

    2014-02-13

    Tumor-propagating cells in acute leukemia maintain a stem/progenitor-like immature phenotype and proliferative capacity. Acute myeloid leukemia (AML) and acute T-lymphoblastic leukemia (T-ALL) originate from different lineages through distinct oncogenic events such as MLL fusions and Notch signaling, respectively. We found that Zfx, a transcription factor that controls hematopoietic stem cell self-renewal, controls the initiation and maintenance of AML caused by MLL-AF9 fusion and of T-ALL caused by Notch1 activation. In both leukemia types, Zfx prevents differentiation and activates gene sets characteristic of immature cells of the respective lineages. In addition, endogenous Zfx contributes to gene induction and transformation by Myc overexpression in myeloid progenitors. Key Zfx target genes include the mitochondrial enzymes Ptpmt1 and Idh2, whose overexpression partially rescues the propagation of Zfx-deficient AML. These results show that distinct leukemia types maintain their undifferentiated phenotype and self-renewal by exploiting a common stem-cell-related genetic regulator. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Genetics of susceptibility for radiation-induced leukemia. Mapping of genes involved to chromosomes 1, 2, and 4, and implications for a viral etiology in the disease. [Mice

    SciTech Connect

    Meruelo, D.; Offer, M.; Flieger, N.

    1981-01-01

    Susceptibility to radiation-induced leukemia in (A/J x B10)F2 mice is encoded for by genes in chromosomes 1, 2, and 4. The loci involved in chromosomes 1 and 4 are close to or similar to xenotropic virus inducibility locus on chromosome 1 and a locus-affecting expression of xenotropic MuLV envelope-related cell surface antigens. Radiation-induced leukemia-1 (Ril-1) on chromosome 2 plays an overriding influence in susceptibility to the disease. This locus might encode ecotropic viral-associated genetic information or might contain cellular sequences with oncogenic potential. These findings are of interest in view of the importance of recombinant viruses to leukemogenesis. Furthermore, it is intriguing that Ril-1 is located in a chromosomal site rich in thymus differentiation-specific loci. An explanation for tissue-specific activation of endogenous viruses is that activation of the virus in question is dependent on differentiation-specific steps.

  3. Co-operative leukemogenesis in acute myeloid leukemia and acute promyelocytic leukemia reveals C/EBPα as a common target of TRIB1 and PML/RARA

    PubMed Central

    Keeshan, Karen; Vieugué, Pauline; Chaudhury, Shahzya; Rishi, Loveena; Gaillard, Coline; Liang, Lu; Garcia, Elaine; Nakamura, Takuro; Omidvar, Nader; Kogan, Scott C.

    2016-01-01

    The PML/RARA fusion protein occurs as a result of the t(15;17) translocation in the acute promyelocytic leukemia subtype of human acute myeloid leukemia. Gain of chromosome 8 is the most common chromosomal gain in human acute myeloid leukemia, including acute promyelocytic leukemia. We previously demonstrated that gain of chromosome 8-containing MYC is of central importance in trisomy 8, but the role of the nearby TRIB1 gene has not been experimentally addressed in this context. We have now tested the hypothesis that both MYC and TRIB1 have functional roles underlying leukemogenesis of trisomy 8 by using retroviral vectors to express MYC and TRIB1 in wild-type bone marrow and in marrow that expressed a PML/RARA transgene. Interestingly, although MYC and TRIB1 readily co-operated in leukemogenesis for wild-type bone marrow, TRIB1 provided no selective advantage to cells expressing PML/RARA. We hypothesized that this lack of co-operation between PML/RARA and TRIB1 reflected a common pathway for their effect: both proteins targeting the myeloid transcription factor C/EBPα. In support of this idea, TRIB1 expression abrogated the all-trans retinoic acid response of acute promyelocytic leukemia cells in vitro and in vivo. Our data delineate the common and redundant inhibitory effects of TRIB1 and PML/RARA on C/EBPα providing a potential explanation for the lack of selection of TRIB1 in human acute promyelocytic leukemia, and highlighting the key role of C/EBPs in acute promyelocytic leukemia pathogenesis and therapeutic response. In addition, the co-operativity we observed between MYC and TRIB1 in the absence of PML/RARA show that, outside of acute promyelocytic leukemia, gain of both genes may drive selection for trisomy 8. PMID:27390356

  4. Developmental Outcome of Childhood Leukemia.

    ERIC Educational Resources Information Center

    Coniglio, Susan J.; Blackman, James A.

    1995-01-01

    Literature on developmental and psychosocial outcomes of childhood leukemia is reviewed, focusing on preschool-age children. Studies are categorized in terms of outcome measures: intelligence/achievement, neuropsychological, memory/attention, and psychosocial tests. Evidence suggests that preschool children with leukemia are at high risk for…

  5. Developmental Outcome of Childhood Leukemia.

    ERIC Educational Resources Information Center

    Coniglio, Susan J.; Blackman, James A.

    1995-01-01

    Literature on developmental and psychosocial outcomes of childhood leukemia is reviewed, focusing on preschool-age children. Studies are categorized in terms of outcome measures: intelligence/achievement, neuropsychological, memory/attention, and psychosocial tests. Evidence suggests that preschool children with leukemia are at high risk for…

  6. Obinutuzumab in chronic lymphocytic leukemia.

    PubMed

    Dupuis, Jehan

    2015-09-01

    Obinutuzumab is the second next-generation monoclonal anti-CD20 antibody (after ofatumumab) to enter clinical practice in chronic lymphocytic leukemia. Its superiority in association with chlorambucil as compared with chlorambucil alone has led to its approval as a first-line treatment for chronic lymphocytic leukemia, for patients who are not candidates for a more intensive treatment.

  7. Cystatins may confer viral resistance in plants by inhibition of a virus-induced cell death phenomenon in which cysteine proteinases are active: cloning and molecular characterization of a cDNA encoding cysteine-proteinase inhibitor (celostatin) from Celosia cristata (crested cock's comb).

    PubMed

    Gholizadeh, Ashraf; Santha, Ittiaparambu Mana; Kohnehrouz, Bahram Baghban; Lodha, Madan Lal; Kapoor, Harish Chander

    2005-12-01

    Cystatins (cysteine proteinase inhibitors) have been recently used in plants as antiviral strategy against those viruses whose replication involves cysteine proteinase activity. We proposed an idea that cystatins may confer resistance by inhibition of a virus-induced cell-death phenomenon in which cysteine proteinases are active. To test this idea, a full-length cDNA library was constructed from the preflowering stage of Celosia cristata (crested cock's comb) leaves, and a cDNA clone with cystatin domain was isolated using an oligonucleotide probe designed on the basis of the conserved peptide of plant cystatins. It was expressed in an Escherichia coli expression system as a fusion protein. The purified recombinant product, termed 'celostatin' (Celosia cystatin), inhibited the enzymatic activity of papain indicating its cystatin activity and prevented TMV (tobacco mosaic virus)-induced hypersensitive-response cell death in Nicotiana glutinosa (a wild species of tobacco) leaves by 65-70% at the concentration of approx. 50 ng/ml. It also offered resistance against TMV and caused normal growth of the test plant. Since the activity of cysteine proteinases is not involved in the TMV replication process, we speculated that inhibition of the hypersensitive response by celostatin may be due to the inactivation of proteolysis involved in the plant cell death programme, a phenomenon that has already been reported in animal systems.

  8. High Throughput Drug Sensitivity Assay and Genomics- Guided Treatment of Patients With Relapsed or Refractory Acute Leukemia

    ClinicalTrials.gov

    2017-07-14

    Acute Leukemia of Ambiguous Lineage; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Acute Myeloid Leukemia; Refractory Acute Myeloid Leukemia; Refractory Adult Acute Lymphoblastic Leukemia; Refractory Childhood Acute Lymphoblastic Leukemia

  9. Review of fusion synfuels

    SciTech Connect

    Fillo, J.A.

    1980-01-01

    Thermonuclear fusion offers an inexhaustible source of energy for the production of hydrogen from water. Depending on design, electric generation efficiencies of approx. 40 to 60% and hydrogen production efficiencies by high-temperature electrolysis of approx. 50 to 65% are projected for fusion reactors using high-temperatures blankets. Fusion/coal symbiotic systems appear economically promising for the first generation of commercial fusion synfuels plants. Coal production requirements and the environmental effects of large-scale coal usage would be greatly reduced by a fusion/coal system. In the long term, there could be a gradual transition to an inexhaustible energy system based solely on fusion.

  10. Acute Myelogenous Leukemia without Maturation with a Retinoic Alpha-Receptor Deletion: A Case Report

    PubMed Central

    Trosclair, Christopher; Pollen, Maressa; Capraro, Gerald; Cotelingam, James; Shackelford, Rodney E.

    2014-01-01

    Acute promyelocytic leukemia (APL) is characterized by a t(15;17) which fuses the 17q retinoic acid alpha-receptor sequence to the 15q PML gene sequence. The resulting fusion product plays a role in the development and maintenance of APL, and is very rarely found in other acute myeloid leukemia (AML) subtypes. Rare complex APL genomic rearrangements have retinoic acid alpha-receptor sequence deletions. Here we report a retinoic acid alpha-receptor sequence deletion in a case of AML without differentiation. To our knowledge, this is the first example of a retinoic acid alpha-receptor sequence deletion in this AML subtype. PMID:25076892

  11. Acute Myelogenous Leukemia without Maturation with a Retinoic Alpha-Receptor Deletion: A Case Report.

    PubMed

    Trosclair, Christopher; Pollen, Maressa; Capraro, Gerald; Cotelingam, James; Shackelford, Rodney E

    2014-05-01

    Acute promyelocytic leukemia (APL) is characterized by a t(15;17) which fuses the 17q retinoic acid alpha-receptor sequence to the 15q PML gene sequence. The resulting fusion product plays a role in the development and maintenance of APL, and is very rarely found in other acute myeloid leukemia (AML) subtypes. Rare complex APL genomic rearrangements have retinoic acid alpha-receptor sequence deletions. Here we report a retinoic acid alpha-receptor sequence deletion in a case of AML without differentiation. To our knowledge, this is the first example of a retinoic acid alpha-receptor sequence deletion in this AML subtype.

  12. Acute Lymphoblastic Leukemia (ALL) (For Parents)

    MedlinePlus

    ... TV, Video Games, and the Internet Acute Lymphoblastic Leukemia (ALL) KidsHealth > For Parents > Acute Lymphoblastic Leukemia (ALL) ... Treatment Coping en español Leucemia linfoblástica aguda About Leukemia Leukemia is a type of cancer that affects ...

  13. Juvenile Myelomonocytic Leukemia (JMML) (For Parents)

    MedlinePlus

    ... TV, Video Games, and the Internet Juvenile Myelomonocytic Leukemia (JMML) KidsHealth > For Parents > Juvenile Myelomonocytic Leukemia (JMML) ... Treatment Coping en español Leucemia mielomonocítica juvenil About Leukemia Leukemia is a type of cancer that affects ...

  14. Chronic Myelogenous Leukemia (CML) (For Parents)

    MedlinePlus

    ... TV, Video Games, and the Internet Chronic Myelogenous Leukemia (CML) KidsHealth > For Parents > Chronic Myelogenous Leukemia (CML) ... Treatment Coping en español Leucemia mielógena crónica About Leukemia Leukemia is a type of cancer that affects ...

  15. Leukemia: Recent advances in biology and treatment

    SciTech Connect

    Gale, R.P.; Golde, D.W.

    1985-01-01

    This book is a compilation of papers presented at a Symposium on the advances in the biology and treatment of leukemia. Topics covered include oncogenes and chromosomes in leukemia - the interactions of oncogenes with hemopoietic cells;the involvement of oncogenes in chronic myelogenous leukemia;oncogene regulation during erythroid differentiation;genomic rearrangements in human cancer;and pathenogenesis of leukemia.

  16. Rebeccamycin Analog in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia, Myelodysplastic Syndrome, Acute Lymphoblastic Leukemia, or Chronic Myelogenous Leukemia

    ClinicalTrials.gov

    2013-01-22

    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); Blastic Phase Chronic Myelogenous Leukemia; Chronic Myelomonocytic Leukemia; de Novo Myelodysplastic Syndromes; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Refractory Anemia With Excess Blasts; Refractory Anemia With Excess Blasts in Transformation; Relapsing Chronic Myelogenous Leukemia; Secondary Acute Myeloid Leukemia; Secondary Myelodysplastic Syndromes

  17. SJG-136 in Treating Patients With Relapsed or Refractory Acute Leukemia, Myelodysplastic Syndromes, Blastic Phase Chronic Myelogenous Leukemia, or Chronic Lymphocytic 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); Blastic Phase Chronic Myelogenous Leukemia; de Novo Myelodysplastic Syndromes; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Refractory Chronic Lymphocytic Leukemia; Relapsing Chronic Myelogenous Leukemia; Secondary Acute Myeloid Leukemia; Secondary Myelodysplastic Syndromes

  18. Current trends in molecular diagnostics of chronic myeloid leukemia.

    PubMed

    Vinhas, Raquel; Cordeiro, Milton; Pedrosa, Pedro; Fernandes, Alexandra R; Baptista, Pedro V

    2017-08-01

    Nearly 1.5 million people worldwide suffer from chronic myeloid leukemia (CML), characterized by the genetic translocation t(9;22)(q34;q11.2), involving the fusion of the Abelson oncogene (ABL1) with the breakpoint cluster region (BCR) gene. Early onset diagnosis coupled to current therapeutics allow for a treatment success rate of 90, which has focused research on the development of novel diagnostics approaches. In this review, we present a critical perspective on current strategies for CML diagnostics, comparing to gold standard methodologies and with an eye on the future trends on nanotheranostics.

  19. A conserved virus-induced cytoplasmic TRAMP-like complex recruits the exosome to target viral RNA for degradation

    PubMed Central

    Molleston, Jerome M.; Sabin, Leah R.; Moy, Ryan H.; Menghani, Sanjay V.; Rausch, Keiko; Gordesky-Gold, Beth; Hopkins, Kaycie C.; Zhou, Rui; Jensen, Torben Heick; Wilusz, Jeremy E.; Cherry, Sara

    2016-01-01

    RNA degradation is tightly regulated to selectively target aberrant RNAs, including viral RNA, but this regulation is incompletely understood. Through RNAi screening in Drosophila cells, we identified the 3′-to-5′ RNA exosome and two components of the exosome cofactor TRAMP (Trf4/5–Air1/2–Mtr4 polyadenylation) complex, dMtr4 and dZcchc7, as antiviral against a panel of RNA viruses. We extended our studies to human orthologs and found that the exosome as well as TRAMP components hMTR4 and hZCCHC7 are antiviral. While hMTR4 and hZCCHC7 are normally nuclear, infection by cytoplasmic RNA viruses induces their export, forming a cytoplasmic complex that specifically recognizes and induces degradation of viral mRNAs. Furthermore, the 3′ untranslated region (UTR) of bunyaviral mRNA is sufficient to confer virus-induced exosomal degradation. Altogether, our results reveal that signals from viral infection repurpose TRAMP components to a cytoplasmic surveillance role where they selectively engage viral RNAs for degradation to restrict a broad range of viruses. PMID:27474443

  20. Axin expression delays herpes simplex virus-induced autophagy and enhances viral replication in L929 cells.

    PubMed

    Choi, Eun-Jin; Kee, Sun-Ho

    2014-02-01

    Axin, a negative regulator of the Wnt signaling pathway, plays a critical role in various cellular events including cell proliferation and cell death. Axin-regulated cell death affects multiple processes, including viral replication. For example, axin expression suppresses herpes simplex virus (HSV)-induced necrotic cell death and enhances viral replication. Based on these observations, this study investigated the involvement of autophagy in regulation of HSV replication and found axin expression inhibits autophagy-mediated suppression of viral replication in L929 cells. HSV infection induced autophagy in a time- and viral dose-dependent manner in control L929 cells (L-EV), whereas virus-induced autophagy was delayed in axin-expressing L929 cells (L-axin). Subsequent analysis showed that induction of autophagy by rapamycin reduced HSV replication, and that inhibiting autophagy by 3-methyladenine (3MA) and beclin-1 knockdown facilitated viral replication in L-EV cells. In addition, preventing autophagy with 3MA suppressed virus-induced cytotoxicity in L-EV cells. In contrast, HSV replication in L-axin cells was resistant to changes in autophagy. These results suggest that axin expression may render L929 cells resistant to HSV-infection induced autophagy, leading to enhanced viral replication. © 2014 The Societies and Wiley Publishing Asia Pty Ltd.

  1. Disruption of plant carotenoid biosynthesis through virus-induced gene silencing affects oviposition behaviour of the butterfly Pieris rapae.

    PubMed

    Zheng, Si-Jun; Snoeren, Tjeerd A L; Hogewoning, Sander W; van Loon, Joop J A; Dicke, Marcel

    2010-05-01

    Optical plant characteristics are important cues to plant-feeding insects. In this article, we demonstrate for the first time that silencing the phytoene desaturase (PDS) gene, encoding a key enzyme in plant carotenoid biosynthesis, affects insect oviposition site selection behaviour. Virus-induced gene silencing employing tobacco rattle virus was used to knock down endogenous PDS expression in three plant species (Arabidopsis thaliana, Brassica nigra and Nicotiana benthamiana) by its heterologous gene sequence from Brassica oleracea. We investigated the consequences of the silencing of PDS on oviposition behaviour by Pieris rapae butterflies on Arabidopsis and Brassica plants; first landing of the butterflies on Arabidopsis plants (to eliminate an effect of contact cues); first landing on Arabidopsis plants enclosed in containers (to eliminate an effect of volatiles); and caterpillar growth on Arabidopsis plants. Our results show unambiguously that P. rapae has an innate ability to visually discriminate between green and variegated green-whitish plants. Caterpillar growth was significantly lower on PDS-silenced than on empty vector control plants. This study presents the first analysis of PDS function in the interaction with an herbivorous insect. We conclude that virus-induced gene silencing is a powerful tool for investigating insect-plant interactions in model and nonmodel plants.

  2. Impact of bacterial colonization on the severity, and accompanying airway inflammation, of virus-induced wheezing in children.

    PubMed

    Yu, D; Wei, L; Zhengxiu, L; Jian, L; Lijia, W; Wei, L; Xiqiang, Y; Xiaodong, Z; Zhou, F; Enmei, L

    2010-09-01

    It is reported that bacterial colonization of the airway in neonates affects the likelihood and severity of subsequent wheezing in childhood. This study aimed to explore the impact of bacterial colonization on the severity of virus-induced wheezing, and accompanying airway inflammation. Nasopharyngeal aspirates (NPAs) from 68 hospitalized children with bronchiolitis and 85 children with recurrent wheezing were obtained. Eleven common respiratory viruses were sought by PCR and/or direct fluorescence assay. Bacteria were isolated from NPAs by routine culture methods. Cell numbers and concentrations of cytokines/chemokines in the NPAs were measured, and nucleated cells were characterized. The frequency of bacterial colonization in children with recurrent wheezing was significantly higher than in children with an initial attack of bronchiolitis. Bacterial colonization accompanying virus infection had no effect on clinical manifestations, duration of hospitalization, concentrations of cytokines/chemokines (except interleukin-10 (IL-10)) or cellularity in the children with bronchiolitis; however, among the children with recurrent wheezing, those who had coexistent non-invasive bacterial colonization and virus infection presented more frequent cyanosis, longer duration of hospitalization, a higher concentration of IL-10 and a higher percentage of neutrophils in NPAs than those with virus infection but without bacterial colonization. Bacterial colonization was common in children with virus-induced wheezing, particularly in the situation of recurrent wheezing. To some extent, bacterial colonization accompanying virus infection may contribute to the severity of the wheezing because of its impact on airway inflammation.

  3. Stimulation of local solid tumour development of the nonproducer Marek's disease tumour transplant JMV by virus-induced immunosuppression.

    PubMed

    Bulow, V V; Weiland, F

    1980-01-01

    Chickens could be protected against lethal lymphoblastic leukaemia due to the nonproducer JMV Marek's disease (MD) tumour transplant by infection with the herpesvirus of turkeys (HVT) or various strains of MD virus. However, solid JMV tumours developed in MD virus-infected birds at the site of intramuscular or subcutaneous transplantation, but tumours never developed at the site of MD virus inoculation. The incidence and extent of local tumour growth, the development of metastases and the inhibition of tumour regression were related to the pathogenicity of the MD virus strains used for pre-treatment of the chickens. Infection of chickens with reticulo-endotheliosis virus (REV-C) or with chick syncytial virus (CSV), which are nonprotective against MD virus or JMV transplants, stimulated local tumour development of the attenuated JMV-A variant of the JMV transplant. Chickens which did not reject local tumours died of visceral JMV tumour metastases. A direct helper mechanism of viral infection on the oncogenicity of transplants was excluded. The results suggested that virus-induced immunosuppression stimulated the development of local JMV tumours which never occurred in normal chickens. Immunity to the JMV transplant, including resistance to lethal leukaemia and successful regression of local tumours, did not coincide with immunity to MD virus-induced visceral lymphomas or nerve lesions. Vaccinal induced tumour immunity evidently was defective. The significance of these results is discussed with reference to immunological functions of MD tumour-specific antigens.

  4. Bendamustine Plus Alemtuzumab for Refractory Chronic Lymphocytic Leukemia (CLL)

    ClinicalTrials.gov

    2013-08-20

    Recurrent Small Lymphocytic Lymphoma; Refractory Chronic Lymphocytic Leukemia; Stage III Chronic Lymphocytic Leukemia; Stage III Small Lymphocytic Lymphoma; Stage IV Chronic Lymphocytic Leukemia; Stage IV Small Lymphocytic Lymphoma

  5. Spectra of Chromosomal Aberrations in 325 Leukemia Patients and Implications for the Development of New Molecular Detection Systems

    PubMed Central

    Choi, Hyun-Jung; Kim, Hye-Ran; Kook, Hoon; Kim, Hyeoung-Joon; Shin, Jong-Hee; Suh, Soon-Pal; Ryang, Dong-Wook

    2011-01-01

    This study investigated the spectrum of chromosomal abnormalities in 325 leukemia patients and developed optimal profiles of leukemic fusion genes for multiplex RT-PCR. We prospectively analyzed blood and bone marrow specimens of patients with acute leukemia. Twenty types of chromosomal abnormalities were detected in 42% from all patients by commercially available multiplex RT-PCR for detecting 28 fusion genes and in 35% by cytogenetic analysis including FISH analysis. The most common cytogenetic aberrations in acute myeloid leukemia patients was PML/PARA, followed by AML1/MGT8 and MLL1, and in acute lymphoid leukemia patients was BCR/ABL, followed by TEL/AML1 and MLL1 gene rearrangement. Among the negative results for multiplex RT-PCR, clinically significant t(3;3)(q21;q26.2), t(8;14)(q24;q32) and i(17)(q10) were detected by conventional cytogenetics. The spectrum and frequency of chromosomal abnormalities in our leukemia patients are differed from previous studies, and may offer optimal profiles of leukemic fusion genes for the development of new molecular detection systems. PMID:21738341

  6. [Molecular targeted therapy in lymphoid leukemias].

    PubMed

    Kojima, Kensuke; Ando, Toshihiko; Kimura, Shinya

    2014-06-01

    Recent advances in the treatment of lymphoid leukemias have incorporated molecular targeted drugs (CD20-targeting rituximab and BCR-ABL tyrosine kinase inhibitors) into the traditional chemotherapeutic agents. This article reviews novel molecular targeted therapies for patients with lymphoid leukemias including acute lymphoblastic leukemia, chronic lymphocytic leukemia, hairly cell leukemia and HTLV-I-related adult T-cell leukemia. Investigational agents that will be discussed in this review include inotuzumab, blinatumomab, alemtuzumab, ofatumumab, ibrutinib, idelalisib, bafetinib, lenalidomide, ABT-199 and mogamulizumab. Novel approaches warrant continued research to improve outcomes for patients with lymphoid leukemias.

  7. Genomic Profiling of Adult and Pediatric B-cell Acute Lymphoblastic Leukemia.

    PubMed

    Liu, Yuan-Fang; Wang, Bai-Yan; Zhang, Wei-Na; Huang, Jin-Yan; Li, Ben-Shang; Zhang, Ming; Jiang, Lu; Li, Jian-Feng; Wang, Ming-Jie; Dai, Yu-Jun; Zhang, Zi-Guan; Wang, Qiang; Kong, Jie; Chen, Bing; Zhu, Yong-Mei; Weng, Xiang-Qin; Shen, Zhi-Xiang; Li, Jun-Min; Wang, Jin; Yan, Xiao-Jing; Li, Yan; Liang, Ying-Min; Liu, Li; Chen, Xie-Qun; Zhang, Wang-Gang; Yan, Jin-Song; Hu, Jian-Da; Shen, Shu-Hong; Chen, Jing; Gu, Long-Jun; Pei, Deqing; Li, Yongjin; Wu, Gang; Zhou, Xin; Ren, Rui-Bao; Cheng, Cheng; Yang, Jun J; Wang, Kan-Kan; Wang, Sheng-Yue; Zhang, Jinghui; Mi, Jian-Qing; Pui, Ching-Hon; Tang, Jing-Yan; Chen, Zhu; Chen, Sai-Juan

    2016-06-01

    Genomic landscapes of 92 adult and 111 pediatric patients with B-cell acute lymphoblastic leukemia (B-ALL) were investigated using next-generation sequencing and copy number alteration analysis. Recurrent gene mutations and fusions were tested in an additional 87 adult and 93 pediatric patients. Among the 29 newly identified in-frame gene fusions, those involving MEF2D and ZNF384 were clinically relevant and were demonstrated to perturb B-cell differentiation, with EP300-ZNF384 inducing leukemia in mice. Eight gene expression subgroups associated with characteristic genetic abnormalities were identified, including leukemia with MEF2D and ZNF384 fusions in two distinct clusters. In subgroup G4 which was characterized by ERG deletion, DUX4-IGH fusion was detected in most cases. This comprehensive dataset allowed us to compare the features of molecular pathogenesis between adult and pediatric B-ALL and to identify signatures possibly related to the inferior outcome of adults to that of children. We found that, besides the known discrepancies in frequencies of prognostic markers, adult patients had more cooperative mutations and greater enrichment for alterations of epigenetic modifiers and genes linked to B-cell development, suggesting difference in the target cells of transformation between adult and pediatric patients and may explain in part the disparity in their responses to treatment.

  8. Donor Umbilical Cord Blood Transplant With or Without Ex-vivo Expanded Cord Blood Progenitor Cells in Treating Patients With Acute Myeloid Leukemia, Acute Lymphoblastic Leukemia, Chronic Myelogenous Leukemia, or Myelodysplastic Syndromes

    ClinicalTrials.gov

    2017-09-14

    Acute Biphenotypic Leukemia; Acute Erythroid Leukemia; Acute Lymphoblastic Leukemia in Remission; Acute Megakaryoblastic Leukemia; Acute Myeloid Leukemia Arising From Previous Myelodysplastic Syndrome; Acute Myeloid Leukemia in Remission; Blasts Under 10 Percent of Bone Marrow Nucleated Cells; Chronic Myelogenous Leukemia, BCR-ABL1 Positive; Mixed Phenotype Acute Leukemia; Myelodysplastic Syndrome; Myelodysplastic Syndrome With Excess Blasts; Pancytopenia; Refractory Anemia; Secondary Acute Myeloid Leukemia

  9. Adult Acute Lymphoblastic Leukemia

    PubMed Central

    Faderl, Stefan; O’Brien, Susan; Pui, Ching-Hon; Stock, Wendy; Wetzler, Meir; Hoelzer, Dieter; Kantarjian, Hagop M.

    2016-01-01

    Acute lymphoblastic leukemia (ALL), a clonal expansion of hematopoietic blasts, is a highly heterogeneous disease comprising many entities for which distinct treatment strategies are pursued. Although ALL is a success story in pediatric oncology, results in adults lag behind those in children. An expansion of new drugs, more reliable immunologic and molecular techniques for the assessment of minimal residual disease, and efforts at more precise risk stratification are generating new aspects of adult ALL therapy. For this review, the authors summarized pertinent and recent literature on ALL biology and therapy, and they discuss current strategies and potential implications of novel approaches to the management of adult ALL. PMID:20101737

  10. Reprogramming of MLL-AF9 leukemia cells into pluripotent stem cells

    PubMed Central

    Liu, Y; Cheng, H; Gao, S; Lu, X; He, F; Hu, L; Hou, D; Zou, Z; Li, Y; Zhang, H; Xu, J; Kang, L; Wang, Q; Yuan, W; Gao, S; Cheng, T

    2014-01-01

    The ‘Yamanaka factors' (Oct4, Sox2, Klf4 and c-Myc) are able to generate induced pluripotent stem (iPS) cells from different cell types. However, to what degree primary malignant cells can be reprogrammed into a pluripotent state has not been vigorously assessed. We established an acute myeloid leukemia (AML) model by overexpressing the human mixed-lineage leukemia-AF9 (MLL-AF9) fusion gene in mouse hematopoietic cells that carry Yamanaka factors under the control of doxycycline (Dox). On addition of Dox to the culture, the transplantable leukemia cells were efficiently converted into iPS cells that could form teratomas and produce chimeras. Interestingly, most chimeric mice spontaneously developed the same type of AML. Moreover, both iPS reprogramming and leukemia reinitiation paths could descend from the same leukemia-initiating cell. RNA-seq analysis showed reversible global gene expression patterns between these interchangeable leukemia and iPS cells on activation or reactivation of MLL-AF9, suggesting a sufficient epigenetic force in driving the leukemogenic process. This study represents an important step for further defining the potential interplay between oncogenic molecules and reprogramming factors during MLL leukemogenesis. More importantly, our reprogramming approach may be expanded to characterize a range of hematopoietic malignancies in order to develop new strategies for clinical diagnosis and treatment. PMID:24150221

  11. Viral membrane fusion

    PubMed Central

    Harrison, Stephen C.

    2015-01-01

    Membrane fusion is an essential step when enveloped viruses enter cells. Lipid bilayer fusion requires catalysis to overcome a high kinetic barrier; viral fusion proteins are the agents that fulfill this catalytic function. Despite a variety of molecular architectures, these proteins facilitate fusion by essentially the same generic mechanism. Stimulated by a signal associated with arrival at the cell to be infected (e.g., receptor or co-receptor binding, proton binding in an endosome), they undergo a series of conformational changes. A hydrophobic segment (a “fusion loop” or “fusion peptide”) engages the target-cell membrane and collapse of the bridging intermediate thus formed draws the two membranes (virus and cell) together. We know of three structural classes for viral fusion proteins. Structures for both pre- and postfusion conformations of illustrate the beginning and end points of a process that can be probed by single-virion measurements of fusion kinetics. PMID:25866377

  12. Tipifarnib in Treating Patients With Chronic Myeloid Leukemia, Chronic Myelomonocytic Leukemia, or Undifferentiated Myeloproliferative Disorders

    ClinicalTrials.gov

    2017-05-08

    Accelerated Phase of Disease; Atypical Chronic Myeloid Leukemia, BCR-ABL1 Negative; Chronic Myelogenous Leukemia, BCR-ABL1 Positive; Chronic Myelomonocytic Leukemia; Chronic Phase of Disease; Myelodysplastic/Myeloproliferative Neoplasm, Unclassifiable; Recurrent Disease

  13. Molecular characterization of three erbB transducing viruses generated during avian leukosis virus-induced erythroleukemia: extensive internal deletion near the kinase domain activates the fibrosarcoma- and hemangioma-inducing potentials of erbB.

    PubMed Central

    Raines, M A; Maihle, N J; Moscovici, C; Moscovici, M G; Kung, H J

    1988-01-01

    Three new erbB transducing viruses generated during avian leukosis virus-induced erythroblastosis have been cloned and sequenced, and their transforming abilities have been analyzed. Provirus 9134 E1 expresses an amino-terminally truncated erbB product that is analogous to the proviral insertionally activated c-erbB gag-erbB fusion product. This virus efficiently induces erythroblastosis, but does not transform fibroblasts in vitro or induce sarcomas in vivo. In contrast, virus 9134 S3 expresses an erbB product identical to the erbB product of 9134 E1, with the exception of a large internal deletion located between the kinase domain and the putative autophosphorylation site, P1. Interestingly, this virus is no longer capable of inducing erythroblastosis, but can induce both fibrosarcomas and hemangiomas in vivo. Provirus 9134 F3 has sustained an approximately 23-amino-acid carboxy-terminal truncation and is capable of inducing both erythroblastosis and sarcomagenesis. This virus expresses an erbB product with the shortest carboxy-terminal truncation sufficient to reveal the sarcomagenic potential of this protein. The distinct transforming properties of these viruses indicate that different structural domains of the erbB product confer distinct disease specificities. Images PMID:2836624

  14. Childhood leukemia genetic bottleneck phenomenon related to TEL-AML1: the postulation by a mathematical model.

    PubMed

    Ivanovski, Petar; Ivanovski, Ivan; Nikolić, Dimitrije; Jovanović, Ivana

    2012-03-01

    Childhood leukemia bottleneck phenomenon is the most mysterious corollary of the prenatal origin discovery of leukemogenic chromosome translocations. The bottleneck is evidence that leukemia initiation, by in utero acquired chromosome translocations that generate functional fusion genes, is far more common than the incidence rate of corresponding leukemia. For childhood TEL-AML1(+) acute lymphoblastic leukemia (ALL) this equates to approximately 100 times. Practically this means that among a hundred children born with TEL-AML1 fusion gene, only one child will later in its life develop ALL. The key data necessary for unraveling of this mystery were discovered in 2002. It was the level of TEL-AML1(+) cells’ frequency. The bottleneck is caused by the very low body TEL-AML1(+) cell count. Only one out of a thousand B cells carries TEL-AML1 fusion gene. TEL-AML1(+) body cell count is low because TEL-AML1 fusion is generated at cell level of 10(-3) to 10(-4) just during the late fetal lymphopoiesis i.e. after the 36th gestational week.

  15. Heterogeneity of leukemia-initiating capacity of chronic myelogenous leukemia stem cells

    PubMed Central

    Zhang, Bin; Li, Ling; Ho, Yinwei; Li, Min; Marcucci, Guido

    2016-01-01

    Chronic myelogenous leukemia (CML) results from transformation of a long-term hematopoietic stem cell (LTHSC) by expression of the BCR-ABL fusion gene. However, BCR-ABL–expressing LTHSCs are heterogeneous in their capacity as leukemic stem cells (LSCs). Although discrepancies in proliferative, self-renewal, and differentiation properties of normal LTHSCs are being increasingly recognized, the mechanisms underlying heterogeneity of leukemic LTHSCs are poorly understood. Using a CML mouse model, we identified gene expression differences between leukemic and nonleukemic LTHSCs. Expression of the thrombopoietin (THPO) receptor MPL was elevated in leukemic LTHSC populations. Compared with LTHSCs with low MPL expression, LTHSCs with high MPL expression showed enhanced JAK/STAT signaling and proliferation in response to THPO in vitro and increased leukemogenic capacity in vivo. Although both G0 and S phase subpopulations were increased in LTHSCs with high MPL expression, LSC capacity was restricted to quiescent cells. Inhibition of MPL expression in CML LTHSCs reduced THPO-induced JAK/STAT signaling and leukemogenic potential. These same phenotypes were also present in LTHSCs from patients with CML, and patient LTHSCs with high MPL expression had reduced sensitivity to BCR-ABL tyrosine kinase inhibitor treatment but increased sensitivity to JAK inhibitors. Together, our studies identify MPL expression levels as a key determinant of heterogeneous leukemia-initiating capacity and drug sensitivity of CML LTHSCs and suggest that high MPL–expressing CML stem cells are potential targets for therapy. PMID:26878174

  16. Magneto-Inertial Fusion

    SciTech Connect

    Wurden, G. A.; Hsu, S. C.; Intrator, T. P.; Grabowski, T. C.; Degnan, J. H.; Domonkos, M.; Turchi, P. J.; Campbell, E. M.; Sinars, D. B.; Herrmann, M. C.; Betti, R.; Bauer, B. S.; Lindemuth, I. R.; Siemon, R. E.; Miller, R. L.; Laberge, M.; Delage, M.

    2015-11-17

    In this community white paper, we describe an approach to achieving fusion which employs a hybrid of elements from the traditional magnetic and inertial fusion concepts, called magneto-inertial fusion (MIF). The status of MIF research in North America at multiple institutions is summarized including recent progress, research opportunities, and future plans.

  17. Cold fusion coatings

    SciTech Connect

    Wachtler, W.R.

    1993-12-31

    Historically, fusion of metals was accomplished through the use of heat. Cold fusion has become a reality with metal to metal fusion occurring at room temperature. The basics of this new technology which can be done in tank, brush or solid form is covered in this paper.

  18. Hot and cold fusion

    SciTech Connect

    Not Available

    1990-08-01

    This article presents an overview of research in cold fusion research and development in cold fusion at the Tokomak Fusion Test Reactor at the Princeton Plasma Physics Lab, and at the inertial containment facility at Lawrence Livermore National Lab. is described.

  19. Magneto-Inertial Fusion

    DOE PAGES

    Wurden, G. A.; Hsu, S. C.; Intrator, T. P.; ...

    2015-11-17

    In this community white paper, we describe an approach to achieving fusion which employs a hybrid of elements from the traditional magnetic and inertial fusion concepts, called magneto-inertial fusion (MIF). Furthermore, the status of MIF research in North America at multiple institutions is summarized including recent progress, research opportunities, and future plans.

  20. Cluster-impact fusion

    SciTech Connect

    Echenique, P.M.; Manson, J.R.; Ritchie, R.H. )

    1990-03-19

    We present a model for the cluster-impact-fusion experiments of Buehler, Friedlander, and Friedman, Calculated fusion rates as a function of bombarding energy for constant cluster size agree well with experiment. The dependence of the fusion rate on cluster size at fixed bombarding energy is explained qualitatively. The role of correlated, coherent collisions in enhanced energy loss by clusters is emphasized.

  1. Cold fusion research

    SciTech Connect

    1989-11-01

    I am pleased to forward to you the Final Report of the Cold Fusion Panel. This report reviews the current status of cold fusion and includes major chapters on Calorimetry and Excess Heat, Fusion Products and Materials Characterization. In addition, the report makes a number of conclusions and recommendations, as requested by the Secretary of Energy.

  2. Leukemia: genetics and prognostic factors.

    PubMed

    Hamerschlak, Nelson

    2008-08-01

    To present the implications of genetics, particularly of cytogenetic techniques, for the diagnosis and prognosis of leukemia. A survey of articles selected from MEDLINE, American Society of Hematology educational programs, the CAPES web portal, the National Comprehensive Cancer Network and textbook chapters. Since the discovery in 1960 by Peter C. Nowel and David Hungerford of the 9:22 translocation (the Philadelphia chromosome), genetics has come to play an important role in hematology, in this case making it possible to diagnose chronic myeloid leukemia and opening doors to research avenues for the whole field of oncology. One point of great interest refers to the implications of these findings for the prognosis of a range of types of leukemia. In acute myeloid leukemia, the karyotype is of fundamental importance to postremission treatment decisions, and molecular factors determine the treatment of individuals with normal karyotypes. In chronic myeloid leukemia, clonal evolution is associated with progression to the blast crisis. Patients on imatinib who cease responding may have mutations on their ABL gene. Finally, in acute lymphoblastic leukemia, factors such as hyperdiploidy and t 12:21 are associated with good prognosis, whereas carriers of t 4:11 and t 9:22 are considered high risk patients. Genetics has come to stay as far as hematology and, in particular, the management of leukemia and its prognostic factors are concerned. These tests should always be carried out and the appropriate treatment adopted in the light of their results, so that optimal patient outcomes can be achieved.

  3. Entinostat and Clofarabine in Treating Patients With Newly Diagnosed, Relapsed, or Refractory Poor-Risk Acute Lymphoblastic Leukemia or Bilineage/Biphenotypic Leukemia

    ClinicalTrials.gov

    2014-07-16

    Acute Leukemias of Ambiguous Lineage; Philadelphia Chromosome Negative Adult Precursor Acute Lymphoblastic Leukemia; Recurrent Adult Acute Lymphoblastic Leukemia; Untreated Adult Acute Lymphoblastic Leukemia

  4. Pathogenesis of the delayed phase of Rauscher virus-induced thrombocytopenia

    SciTech Connect

    Grau, G.E.; Morrow, D.; Izui, S.; Lambert, P.H.

    1986-01-01

    BALB/c (H-2/sup d/) mice injected with Rauscher murine leukemia virus (RMuLV) developed two phases of thrombocytopenia: an acute phase, probably due to direct virus-platelet interactions, and a delayed phase, starting 2 to 3 wk after virus injection, which was associated with the infection of megakaryocytes by RMuLV and with the expression of RMuLV gp70 and p30 antigens on platelet membranes. This study was concerned with the pathogenesis of this second phase of thrombocytopenia. During this period, the number of marrow megakaryocytes was increased. A peripheral platelet destruction was further indicated by reduced platelet life span. It was shown that radiolabeled platelets, either normal or infected, were submitted to a more rapid clearance in infected recipients than in normal recipients. This might be due to the splenomegaly observed in infected recipients. However, the immediate clearance of gp70/sup +/ platelets was more accelerated in infected recipients with high titers of serum anti-gp70 antibodies than in infected recipients without detectable serum anti-gp70 antibodies. These results suggest that specific clearance of gp70/sup +/ platelets in the presence of significant amounts of serum antiviral antibodies and nonspecific hypersplenism play a role in the development of delayed thrombocytopenia in RMuLV-infected mice.

  5. Marrow transplantation for leukemia

    SciTech Connect

    Thomas, E.D.

    1981-07-01

    Marrow transplantation for selected patients with leukemia, as for patients with severe combined immunologic deficiency or severe aplastic anemia, has now become an accepted clinical procedure. For patients with acute leukemia who have relapsed after achieving a remission of chemotherapy, marrow grafting from an identical twin or an HLA-identical sibling has now been demonstrated to produce median remissions as long as or longer than any reported for combination chemotherapy. In contrast to chemotherapy, marrow transplantation offers the possibility of cure for a small but significant fraction of these patients. Marrow transplantation for patients with ANL in first remission has now resulted in median survivals much longer than any reported with chemotherapy. Although it now appears that more than 50% of these patients can be cured with marrow transplantation, a much longer follow-up is indicated since some patients who achieve a complete remission with combination chemotherapy are now living for a long time, and some of these patients (less than 20%) may also be cured. Current intensive research with new modalities such as interferon, Acyclovir, Cyclosporin A, and monoclonal antibodies can reasonably be expected to improve the overall results of marrow transplantation.

  6. Avian reovirus-induced syncytium formation is independent of infectious progeny virus production and enhances the rate, but is not essential, for virus-induced cytopathology and virus egress.

    PubMed

    Duncan, R; Chen, Z; Walsh, S; Wu, S

    1996-10-15

    The nonenveloped avian reoviruses represent a distinct antigenic subgroup of orthoreoviruses. Unlike their mammalian counterparts, the avian reoviruses exhibit the unusual property of inducing rapid and extensive syncytium formation in cell cultures, a cytopathic effect more commonly associated with enveloped virus replication. While the syncytium-inducing capability of avian reovirus has been known for quite some time, the relationship between cell fusion and the virus replication cycle has not been determined. The conservation of the syncytial phenotype among all field isolates of avian reovirus suggests that avian reovirus-induced syncytium formation either reflects an essential step in the virus replication cycle involving intracellular membrane interactions or that cell fusion contributes to enhanced virus replication in infected animals. In order to distinguish between these possibilities, we have examined several aspects of virus replication in the presence of inhibitors of syncytium formation. Inhibitors of intracellular vesicle transport and O-linked glycosylation eliminated or markedly reduced syncytium formation with little effect on the rate or extent of virus macromolecular synthesis and infectious progeny virus production. Moreover, syncytium formation was not required for virus-induced cytopathology or virus egress but did significantly enhance the rate of both of these processes. The data indicate that, unlike the syncytium-inducing enveloped viruses, the membrane interactions and protein trafficking required for avian reovirus-induced syncytium formation do not reflect the sequelae of an essential step in the virus replication cycle. These results suggest that the conservation of the avian reovirus syncytial phenotype may reflect a fortuitous aspect of virus replication which confers advantages associated with the rapid spread of the virus within an infected host.

  7. MicroRNA profiling can classify acute leukemias of ambiguous lineage as either acute myeloid leukemia or acute lymphoid leukemia.

    PubMed

    de Leeuw, David C; van den Ancker, Willemijn; Denkers, Fedor; de Menezes, Renée X; Westers, Theresia M; Ossenkoppele, Gert J; van de Loosdrecht, Arjan A; Smit, Linda

    2013-04-15

    Classification of acute leukemia is based on the commitment of leukemic cells to the myeloid or the lymphoid lineage. However, a small percentage of acute leukemia cases lack straightforward immunophenotypical lineage commitment. These leukemias of ambiguous lineage represent a heterogeneous category of acute leukemia that cannot be classified as either acute myeloid leukemia (AML) or acute lymphoid leukemia (ALL). The lack of clear classification of acute leukemias of ambiguous lineage as either AML or ALL is a hurdle in treatment choice for these patients. Here, we compared the microRNA (miRNA) expression profiles of 17 cases with acute leukemia of ambiguous lineage and 16 cases of AML, B-cell acute lymphoid leukemia (B-ALL), and T-cell acute lymphoid leukemia (T-ALL). We show that leukemias of ambiguous lineage do not segregate as a separate entity but exhibit miRNA expression profiles similar to AML, B-ALL, or T-ALL. We show that by using only 5 of the most lineage-discriminative miRNAs, we are able to define acute leukemia of ambiguous lineage as either AML or ALL. Our results indicate the presence of a myeloid or lymphoid lineage-specific genotype, as reflected by miRNA expression, in these acute leukemias despite their ambiguous immunophenotype. miRNA-based classification of acute leukemia of ambiguous lineage might be of additional value in therapeutic decision making.

  8. The PlagL2 transcription factor activates Mpl transcription and signaling in hematopoietic progenitor and leukemia cells

    PubMed Central

    Landrette, Sean F; Madera, Dmitri; He, Feng; Castilla, Lucio H

    2010-01-01

    Cytokine signaling pathways are frequent targets of oncogenic mutations in acute myeloid leukemia, promoting proliferation and survival. We have previously shown that the transcription factor PLAGL2 promotes proliferation and cooperates with the leukemia fusion protein Cbfβ-SMMHC in acute myeloid leukemia development. Here we show that PLAGL2 upregulates expression of the thrombopoietin receptor Mpl, using 2 consensus sites in its proximal promoter. We also show that Mpl overexpression efficiently cooperates with Cbfβ-SMMHC in development of leukemia in mice. Finally, we demonstrate that PlagL2-expressing leukemic cells show hyper-activation of Jak2 and downstream STAT5, Akt and Erk1/2 pathways in response to Tpo ligand. These results show that PlagL2 expression activates expression of Mpl in hematopoietic progenitors, and that upregulation of wild type Mpl provides an oncogenic signal in cooperation with CBFβ-SMMHC in mice. PMID:21263445

  9. Magnetized target fusion and fusion propulsion

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, Ronald C.

    2002-01-01

    Magnetized target fusion (MTF) is a thermonuclear fusion concept that is intermediate between the two mainline approaches, magnetic confinement and inertial confinement fusion (MCF and ICF). MTF incorporates some aspects of each and offers advantages over each of the mainline approaches. First, it provides a means of reducing the driver power requirements, thereby admitting a wider range of drivers than ICF. Second, the magnetic field is only used for insulation, not confinement, and the plasma is wall confined, so that plasma instabilities are traded in for hydrodynamic instabilities. However, the degree of compression required to reach fusion condition is lower than for ICF, so that hydrodynamic instabilities are much less threatening. The standoff driver innovation proposes to dynamically form the target plasma and a gaseous shell that compresses and confines the target plasma. Therefore, fusion target fabrication is traded in for a multiplicity of plasma guns, which must work in synchrony. The standoff driver embodiment of MTF leads to a fusion propulsion system concept that is potentially compact and lightweight. We will discuss the underlying physics of MTF and some of the details of the fusion propulsion concept using the standoff driver approach. We discuss here the optimization of an MTF target design for space propulsion. .

  10. Different cytokine profile and eosinophil activation are involved in rhinovirus- and RS virus-induced acute exacerbation of childhood wheezing.

    PubMed

    Kato, Masahiko; Tsukagoshi, Hiroyuki; Yoshizumi, Masakazu; Saitoh, Mika; Kozawa, Kunihisa; Yamada, Yoshiyuki; Maruyama, Kenichi; Hayashi, Yasuhide; Kimura, Hirokazu

    2011-02-01

    Because little information is available on eosinophil activation and cytokine response in virus-induced wheezing, we attempted to detect respiratory viruses and measure eosinophil cationic protein (ECP), and 27 types of cytokines/chemokines in both serum and nasal secretions from children with wheezing. This study was an observational, case-control investigation of 267 subjects, who were visited and/or hospitalized with acute respiratory symptoms (with wheezing: men, 115; women, 59; mean/median age, 3.6/3.0 years) or who were visited for regular physical examination and treatment (non-symptomatic wheezing: men, 48; women, 31; mean/median, 5.0/4.7 years), and 14 control subjects (controls: men, 9; women, 5; mean/median, 3.6/3.7 years). We detected viruses in nasal secretions from 174 patients with acute exacerbations of wheezing using antigen detection kits or reverse transcription-polymerase chain reaction, followed by direct DNA sequencing analysis. We measured peripheral eosinophil counts, and serum concentrations of ECP and 27 cytokines/chemokines using a multiplex bead-based assay in patients with wheezing or non-symptomatic wheezing. We also examined nasal ECP and 27 cytokines/chemokines in patients with wheezing. Of 174 samples from wheezing exacerbations, rhinovirus was detected in 59; respiratory syncytial (RS) virus in 44; enterovirus in 17; other viruses in 19; and no viruses in 35. Serum concentrations of ECP, IL-5, IL-6, IL-1ra, and IP-10 were significantly elevated in rhinovirus-induced wheezing compared with non-symptomatic wheezing. Similarly, serum ECP, IL-5, and IP-10 were significantly higher in rhinovirus-induced wheezing than in controls. On the other hand, IL-1ra and IP-10, but not ECP and IL-5 were significantly higher in RS virus-induced wheezing than in controls. Furthermore, only IL-5 was significantly elevated in the rhinovirus group compared with the RS virus group in both serum and nasal secretions. Different cytokine profile and

  11. 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

  12. What Should You Ask Your Doctor about Acute Lymphocytic Leukemia?

    MedlinePlus

    ... Types What Should You Ask Your Doctor About Acute Lymphocytic Leukemia? It is important to have frank, honest discussions ... Your Doctor About Acute Lymphocytic Leukemia? More In Acute Lymphocytic Leukemia About Acute Lymphocytic Leukemia Causes, Risk Factors, and ...

  13. What Should You Ask Your Doctor about Chronic Lymphocytic Leukemia?

    MedlinePlus

    ... Should You Ask Your Doctor About Chronic Lymphocytic Leukemia? As you cope with cancer and cancer treatment, ... About Chronic Lymphocytic Leukemia? More In Chronic Lymphocytic Leukemia About Chronic Lymphocytic Leukemia Causes, Risk Factors, and ...

  14. What Should You Ask Your Doctor about Chronic Myeloid Leukemia?

    MedlinePlus

    ... Should You Ask Your Doctor About Chronic Myeloid Leukemia? As you cope with cancer and cancer treatment, ... About Chronic Myeloid Leukemia? More In Chronic Myeloid Leukemia About Chronic Myeloid Leukemia Causes, Risk Factors, and ...

  15. What Are the Risk Factors for Chronic Myeloid Leukemia?

    MedlinePlus

    ... What Are the Risk Factors for Chronic Myeloid Leukemia? A risk factor is something that affects a ... Myeloid Leukemia Be Prevented? More In Chronic Myeloid Leukemia About Chronic Myeloid Leukemia Causes, Risk Factors, and ...

  16. What's New in Chronic Lymphocytic Leukemia Research and Treatment?

    MedlinePlus

    ... Lymphocytic Leukemia (CLL) About Chronic Lymphocytic Leukemia What's New in Chronic Lymphocytic Leukemia Research and Treatment? Many ... person's outlook and whether they will need treatment. New drugs for chronic lymphocytic leukemia Dozens of new ...

  17. Modulating Leukemia-Initiating Cell Quiescence to Improve Leukemia Treatment

    DTIC Science & Technology

    2015-09-01

    chromosome translocation. We utilized a mouse model of human acute myeloid leukemia (AML) induced by the MLL-AF9 oncogene to determine the role of Necdin...function as an endogenous anti-mitotic and anti-apoptotic protein in post-mitotic neurons [1]. The necdin gene is located on chromosome 15 in human and...Downing, J.R. (1996). AML1, the target of multiple chromosomal translocations in human leukemia, is essential for normal fetal liver hematopoiesis. Cell

  18. The protective immune response against infectious bronchitis virus induced by multi-epitope based peptide vaccines.

    PubMed

    Yang, Tai; Wang, Hong-Ning; Wang, Xue; Tang, Jun-Ni; Lu, Dan; Zhang, Yun-Fei; Guo, Zi-Cheng; Li, Yu-Ling; Gao, Rong; Kang, Run-Min

    2009-07-01

    Peptide vaccine was found to be an effective and powerful approach to a variety of pathogens. To explore multi-epitope based peptide vaccines against infectious bronchitis virus (IBV), the immunogenic peptides were fused to the 3' terminal of glutathione S transferase gene (GST) and expressed in Escherichia coli. ELISA and Western blot analysis showed that the purified fusion proteins had excellent immune activity with chicken anti-IBV serum. During the vaccination course, the candidate peptide vaccines induced strong humoral and cellular response, and provided up to 80.0% immune protection, while all non-immunized chickens in the negative control group manifested obvious typical symptoms and died after virus challenge. Our finding provides a new way to develop multi-epitope based peptide vaccine against IBV.

  19. CCI-779 in Treating Patients With Relapsed or Refractory Acute Myeloid Leukemia, Acute Lymphoblastic Leukemia, Myelodysplastic Syndromes, or Chronic Myelogenous Leukemia in Blastic Phase

    ClinicalTrials.gov

    2013-01-22

    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); Blastic Phase Chronic Myelogenous Leukemia; Chronic Myelomonocytic Leukemia; de Novo Myelodysplastic Syndromes; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Refractory Anemia With Excess Blasts; Refractory Anemia With Excess Blasts in Transformation; Relapsing Chronic Myelogenous Leukemia; Secondary Myelodysplastic Syndromes

  20. Eliciting cytotoxic T lymphocytes against acute myeloid leukemia-derived antigens: evaluation of dendritic cell-leukemia cell hybrids and other antigen-loading strategies for dendritic cell-based vaccination.

    PubMed

    Galea-Lauri, Joanna; Darling, David; Mufti, Ghulam; Harrison, Phillip; Farzaneh, Farzin

    2002-08-01

    Dendritic cells (DC) have been successfully used in clinical pilot studies to induce tumor-specific immunity as well as clinical response in selected patients. However, DC-based immunotherapy remains a challenge and several parameters need to be examined in order to optimize the induction of anti-tumor immune responses. This study focuses on DC vaccination for leukemia and evaluates the in vitro efficacy of three different strategies for generating antigen-loaded DC-based vaccines for the induction of major histocompatibility complex (MHC) class I-restricted anti-leukemia cytotoxic T lymphocyte (CTL) responses. These included direct fusion of DC with leukemia cells to generate DC-leukemia cell hybrids, and DC pulsed with either apoptotic leukemia cell fragments or whole tumor cell lysates. Using either the U937 cell line or primary human acute myeloid leukemia blasts (AML), DC-leukemia cell hybrids were found to be the most potent in vitro inducers of CTL activity. DC pulsed with apoptotic tumor cell fragments were less efficient, but induced a more potent CTL response compared to tumor lysate-pulsed DC. The CTL responses were both MHC class I-restricted and antigen-specific, as shown by the inability of the CTL to lyse other control targets. The data presented here suggest that the method of antigen loading onto DC may be critical in the design of tumor vaccines.

  1. Viral membrane fusion

    SciTech Connect

    Harrison, Stephen C.

    2015-05-15

    Membrane fusion is an essential step when enveloped viruses enter cells. Lipid bilayer fusion requires catalysis to overcome a high kinetic barrier; viral fusion proteins are the agents that fulfill this catalytic function. Despite a variety of molecular architectures, these proteins facilitate fusion by essentially the same generic mechanism. Stimulated by a signal associated with arrival at the cell to be infected (e.g., receptor or co-receptor binding, proton binding in an endosome), they undergo a series of conformational changes. A hydrophobic segment (a “fusion loop” or “fusion peptide”) engages the target-cell membrane and collapse of the bridging intermediate thus formed draws the two membranes (virus and cell) together. We know of three structural classes for viral fusion proteins. Structures for both pre- and postfusion conformations of illustrate the beginning and end points of a process that can be probed by single-virion measurements of fusion kinetics. - Highlights: • Viral fusion proteins overcome the high energy barrier to lipid bilayer merger. • Different molecular structures but the same catalytic mechanism. • Review describes properties of three known fusion-protein structural classes. • Single-virion fusion experiments elucidate mechanism.

  2. Cilengitide in Treating Patients With Acute Myeloid Leukemia

    ClinicalTrials.gov

    2013-01-23

    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 Without Maturation (M1); Adult Acute Myeloid Leukemia in Remission; Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Erythroleukemia (M6a); Adult Pure Erythroid Leukemia (M6b)

  3. Identification of novel fusion genes with 28S ribosomal DNA in hematologic malignancies.

    PubMed

    Kobayashi, Satoru; Taki, Tomohiko; Nagoshi, Hisao; Chinen, Yoshiaki; Yokokawa, Yuichi; Kanegane, Hirokazu; Matsumoto, Yosuke; Kuroda, Junya; Horiike, Shigeo; Nishida, Kazuhiro; Taniwaki, Masafumi

    2014-04-01

    Fusion genes are frequently observed in hematologic malignancies and soft tissue sarcomas, and are usually associated with chromosome abnormalities. Many of these fusion genes create in-frame fusion transcripts that result in the production of fusion proteins, and some of which aid tumorigenesis. These fusion proteins are often associated with disease phenotype and clinical outcome, and act as markers for minimal residual disease and indicators of therapeutic targets. Here, we identified the 28S ribosomal DNA (RN28S1) gene as a novel fusion partner of the B-cell leukemia/lymphoma 11B gene (BCL11B), the immunoglobulin κ variable 3-20 gene (IGKV3-20) and the component of oligomeric Golgi complex 1 gene (COG1) in hematologic malignancies. The RN28S1-BCL11B fusion transcript was identified in a case with mixed-lineage (T/myeloid) acute leukemia having t(6;14)(q25;q32) by cDNA bubble PCR using BCL11B primers; however, the gene fused to BCL11B on 14q32 was not on 6q25. IGKV3-20-RN28S1 and COG1-RN28S1 fusion transcripts were identified in the Burkitt lymphoma cell line HBL-5, and the multiple myeloma cell line KMS-18. RN28S1 would not translate, and the breakpoints in partner genes of RN28S1 were within the coding exons, suggesting that disruption of fusion partners by fusion to RN28S1 is the possible mechanism of tumorigenesis. Although further analysis is needed to elucidate the mechanism(s) through which these RN28S1-related fusions play roles in tumorigenesis, our findings provide important insights into the role of rDNA function in human genomic architecture and tumorigenesis.

  4. Targeting Aberrant Epigenetic Networks Mediated by PRMT1 and KDM4C in Acute Myeloid Leukemia

    PubMed Central

    Cheung, Ngai; Fung, Tsz Kan; Zeisig, Bernd B.; Holmes, Katie; Rane, Jayant K.; Mowen, Kerri A.; Finn, Michael G.; Lenhard, Boris; Chan, Li Chong; So, Chi Wai Eric

    2016-01-01

    Summary Transcriptional deregulation plays a major role in acute myeloid leukemia, and therefore identification of epigenetic modifying enzymes essential for the maintenance of oncogenic transcription programs holds the key to better understanding of the biology and designing effective therapeutic strategies for the disease. Here we provide experimental evidence for the functional involvement and therapeutic potential of targeting PRMT1, an H4R3 methyltransferase, in various MLL and non-MLL leukemias. PRMT1 is necessary but not sufficient for leukemic transformation, which requires co-recruitment of KDM4C, an H3K9 demethylase, by chimeric transcription factors to mediate epigenetic reprogramming. Pharmacological inhibition of KDM4C/PRMT1 suppresses transcription and transformation ability of MLL fusions and MOZ-TIF2, revealing a tractable aberrant epigenetic circuitry mediated by KDM4C and PRMT1 in acute leukemia. PMID:26766589

  5. 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

  6. The role of the membrane-spanning domain sequence in glycoprotein-mediated membrane fusion.

    PubMed

    Taylor, G M; Sanders, D A

    1999-09-01

    The role of glycoprotein membrane-spanning domains in the process of membrane fusion is poorly understood. It has been demonstrated that replacing all or part of the membrane-spanning domain of a viral fusion protein with sequences that encode signals for glycosylphosphatidylinositol linkage attachment abrogates membrane fusion activity. It has been suggested, however, that the actual amino acid sequence of the membrane-spanning domain is not critical for the activity of viral fusion proteins. We have examined the function of Moloney murine leukemia virus envelope proteins with substitutions in the membrane-spanning domain. Envelope proteins bearing substitutions for proline 617 are processed and incorporated into virus particles normally and bind to the viral receptor. However, they possess greatly reduced or undetectable capacities for the promotion of membrane fusion and infectious virus particle formation. Our results imply a direct role for the residues in the membrane-spanning domain of the murine leukemia virus envelope protein in membrane fusion and its regulation. They also support the thesis that membrane-spanning domains possess a sequence-dependent function in other protein-mediated membrane fusion events.

  7. Vaccine Therapy Plus Immune Adjuvant in Treating Patients With Chronic Myeloid Leukemia, Acute Myeloid Leukemia, or Myelodysplastic Syndrome

    ClinicalTrials.gov

    2013-01-04

    Accelerated Phase Chronic Myelogenous Leukemia; Adult Acute Myeloid Leukemia in Remission; Chronic Phase Chronic Myelogenous Leukemia; Previously Treated Myelodysplastic Syndromes; Refractory Anemia With Excess Blasts; Refractory Anemia With Excess Blasts in Transformation; Relapsing Chronic Myelogenous Leukemia

  8. How Is Childhood Leukemia Classified?

    MedlinePlus

    ... Classification based on how the leukemia cells look (morphology) In the past, doctors used the French-American- ... of AML are classified mainly based on their morphology (how they look under the microscope). There are ...

  9. Pharmacogenetics in Acute Lymphoblastic Leukemia

    PubMed Central

    Cheok, Meyling H.; Pottier, Nicolas; Kager, Leo

    2009-01-01

    Progress in the treatment of acute leukemia in children has been remarkable, from a disease being lethal four decades ago to current cure rates exceeding 80%. This exemplary progress is largely due to the optimization of existing treatment modalities rather than the discovery of new antileukemic agents. However, despite these high cure rates, the annual number of children whose leukemia relapses after their initial therapy remains greater than that of new cases of most types of childhood cancers. The aim of pharmacogenetics is to develop strategies to personalize treatment and tailor therapy to individual patients, with the goal of optimizing efficacy and safety through better understanding of human genome variability and its influence on drug response. In this review, we summarize recent pharmacogenomic studies related to the treatment of pediatric acute lymphoblastic leukemia. These studies illustrate the promise of pharmacogenomics to further advance the treatment of human cancers, with childhood leukemia serving as a paradigm. PMID:19100367

  10. Down syndrome preleukemia and leukemia.

    PubMed

    Maloney, Kelly W; Taub, Jeffrey W; Ravindranath, Yaddanapudi; Roberts, Irene; Vyas, Paresh

    2015-02-01

    Children with Down syndrome (DS) and acute leukemias acute have unique biological, cytogenetic, and intrinsic factors that affect their treatment and outcome. Myeloid leukemia of Down syndrome (ML-DS) is associated with high event-free survival (EFS) rates and frequently preceded by a preleukemia condition, the transient abnormal hematopoiesis (TAM) present at birth. For acute lymphoblastic leukemia (ALL), their EFS and overall survival are poorer than non-DS ALL, it is important to enroll them on therapeutic trials, including relapse trials; investigate new agents that could potentially improve their leukemia-free survival; and strive to maximize the supportive care these patients need. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Linking Pesticide Exposure with Pediatric Leukemia: Potential Underlying Mechanisms

    PubMed Central

    Hernández, Antonio F.; Menéndez, Pablo

    2016-01-01

    Leukemia is the most common cancer in children, representing 30% of all childhood cancers. The disease arises from recurrent genetic insults that block differentiation of hematopoietic stem and/or progenitor cells (HSPCs) and drives uncontrolled proliferation and survival of the differentiation-blocked clone. Pediatric leukemia is phenotypically and genetically heterogeneous with an obscure etiology. The interaction between genetic factors and environmental agents represents a potential etiological driver. Although information is limited, the principal toxic mechanisms of potential leukemogenic agents (e.g., etoposide, benzene metabolites, bioflavonoids and some pesticides) include topoisomerase II inhibition and/or excessive generation of free radicals, which may induce DNA single- and double-strand breaks (DNA-DSBs) in early HSPCs. Chromosomal rearrangements (duplications, deletions and translocations) may occur if these lesions are not properly repaired. The initiating hit usually occurs in utero and commonly leads to the expression of oncogenic fusion proteins. Subsequent cooperating hits define the disease latency and occur after birth and may be of a genetic, epigenetic or immune nature (i.e., delayed infection-mediated immune deregulation). Here, we review the available experimental and epidemiological evidence linking pesticide exposure to infant and childhood leukemia and provide a mechanistic basis to support the association, focusing on early initiating molecular events. PMID:27043530

  12. Linking Pesticide Exposure with Pediatric Leukemia: Potential Underlying Mechanisms.

    PubMed

    Hernández, Antonio F; Menéndez, Pablo

    2016-03-29

    Leukemia is the most common cancer in children, representing 30% of all childhood cancers. The disease arises from recurrent genetic insults that block differentiation of hematopoietic stem and/or progenitor cells (HSPCs) and drives uncontrolled proliferation and survival of the differentiation-blocked clone. Pediatric leukemia is phenotypically and genetically heterogeneous with an obscure etiology. The interaction between genetic factors and environmental agents represents a potential etiological driver. Although information is limited, the principal toxic mechanisms of potential leukemogenic agents (e.g., etoposide, benzene metabolites, bioflavonoids and some pesticides) include topoisomerase II inhibition and/or excessive generation of free radicals, which may induce DNA single- and double-strand breaks (DNA-DSBs) in early HSPCs. Chromosomal rearrangements (duplications, deletions and translocations) may occur if these lesions are not properly repaired. The initiating hit usually occurs in utero and commonly leads to the expression of oncogenic fusion proteins. Subsequent cooperating hits define the disease latency and occur after birth and may be of a genetic, epigenetic or immune nature (i.e., delayed infection-mediated immune deregulation). Here, we review the available experimental and epidemiological evidence linking pesticide exposure to infant and childhood leukemia and provide a mechanistic basis to support the association, focusing on early initiating molecular events.

  13. Characterization of Clonality of Epstein-Barr Virus-Induced Human B Lymphoproliferative Disease in Mice with Severe Combined Immunodeficiency

    PubMed Central

    Nakamine, Hirokazu; Masih, Aneal S.; Okano, Motohiko; Taguchi, Yuichi; Pirruccello, Samuel J.; Davis, Jack R.; Mahloch, Mark L.; Beisel, Kirk W.; Kleveland, Kimberly; Sanger, Warren G.; Purtilo, David T.

    1993-01-01

    To improve the diagnostic accuracy and understanding of the pathogenesis of lymphoproliferative diseases (LPDs) occurring in immunosuppressed transplant recipients (post-transplantation LPD), clonality of Epstein-Barr virus-induced human LPDs in mice with severe combined immunodeficiency was examined by analyzing: 1) human immunoglobulin genes and their products, 2) the clonality of Epstein-Barr virus DNA, and 3) genetic alteration of c-myc or bcl-2 genes. A spectrum of clonality was found in the LPDs comparable with that reported for post-transplantation LPDs, although rearrangements of c-myc or bcl-2 genes were not detected. It is confirmed that this system is useful in terms of clonality for understanding the early phases in the pathogenesis of post-transplantation LPD or LPD in immune deficient patients. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5 PMID:8380952

  14. Virus-induced diabetes mellitus. VI. Genetically determined host differences in the replicating of encephalomyocarditis virus in pancreatic beta cells

    PubMed Central

    1976-01-01

    Beta cells were isolated from strains of mice that were susceptible and resistant to encephalomyocarditis (EMC) viral-induced diabetes mellitus. Beta cells from susceptible mice that were infected in vivo with EMC virus showed higher viral titers, more severe degranulation, and lower concentrations of immunoreactive insulin than beta cells from resistant mice. Immunofluorescence and infectious center assays revealed that pancreas from susceptible mice contained at least 10 times more infected cells than pancreas from resistant mice. Beta cell cultures prepared from susceptible mice and infected in vitro also showed higher viral titers and more severe cytopathologic changes than beta cell cultures from resistant mice. In contrast to beta cell cultures, virus replicated equally well in primary embryo and kidney cell cultures from susceptible and resistant strains of mice. It is concluded that the development of EMC virus-induced diabetes is related to genetically determined host differences in the capacity of the virus to infect beta cells. PMID:177713

  15. Inhibition of megakaryocyte development in the bone marrow underlies dengue virus-induced thrombocytopenia in humanized mice.

    PubMed

    Sridharan, Aishwarya; Chen, Qingfeng; Tang, Kin Fai; Ooi, Eng Eong; Hibberd, Martin L; Chen, Jianzhu

    2013-11-01

    A characteristic clinical feature of dengue virus infection is thrombocytopenia, though its underlying mechanism is not definitively determined. By adoptive transfer of human CD34(+) fetal liver cells into immunodeficient mice, we have constructed humanized mice with significant levels of human platelets, monocytes/macrophages, and hepatocytes. Infection of these mice with both lab-adapted and clinical strains of dengue virus induces characteristic human hematological changes, including transient leukopenia and thrombocytopenia. We show that the specific depletion of human platelets is not mediated by antibodies in the periphery or reduced production of human thrombopoietin in the liver but reduction of human megakaryocytes and megakaryocyte progenitors in the bone marrow of the infected mice. These findings identify inhibition of platelet production in the bone marrow as a key mechanism underlying dengue-induced thrombocytopenia and suggest the utility of the improved humanized mouse model in studying dengue virus infection and pathogenesis in a human cell context.

  16. Inhibition of Megakaryocyte Development in the Bone Marrow Underlies Dengue Virus-Induced Thrombocytopenia in Humanized Mice

    PubMed Central

    Sridharan, Aishwarya; Chen, Qingfeng; Tang, Kin Fai; Ooi, Eng Eong

    2013-01-01

    A characteristic clinical feature of dengue virus infection is thrombocytopenia, though its underlying mechanism is not definitively determined. By adoptive transfer of human CD34+ fetal liver cells into immunodeficient mice, we have constructed humanized mice with significant levels of human platelets, monocytes/macrophages, and hepatocytes. Infection of these mice with both lab-adapted and clinical strains of dengue virus induces characteristic human hematological changes, including transient leukopenia and thrombocytopenia. We show that the specific depletion of human platelets is not mediated by antibodies in the periphery or reduced production of human thrombopoietin in the liver but reduction of human megakaryocytes and megakaryocyte progenitors in the bone marrow of the infected mice. These findings identify inhibition of platelet production in the bone marrow as a key mechanism underlying dengue-induced thrombocytopenia and suggest the utility of the improved humanized mouse model in studying dengue virus infection and pathogenesis in a human cell context. PMID:23966397

  17. Influenza virus-induced encephalopathy in mice: interferon production and natural killer cell activity during acute infection.

    PubMed Central

    Wabuke-Bunoti, M A; Bennink, J R; Plotkin, S A

    1986-01-01

    Mice injected intracerebrally with infectious influenza virus (60 hemagglutinin units) developed lethargy, seizures, comas, and died 2 to 5 days postinfection. As early as 6 h after infection, the cerebrospinal fluid (CSF) in these animals was infiltrated with polymorphonuclear cells, mononuclear leukocytes, and large granular lymphocytes. Potent natural killer (NK) cell activity was observed for both CSF and spleen cell populations over the same period. This NK cell activity correlated with interferon (IFN) levels in the CSF and serum. Treatment of lethally infected mice with either anti-IFN alpha-IFN beta or anti-ganglio-n-tetraoglyceramide antiserum ameliorated the disease, reduced mortality, and effected changes in the relative proportions of inflammatory cell populations infiltrating the CSF. The possible significance of IFN and NK cell activity in the development of this influenza virus-induced encephalopathy is discussed. PMID:2431159

  18. Virus induced gene silencing (VIGS) for functional analysis of wheat genes involved in Zymoseptoria tritici susceptibility and resistance.

    PubMed

    Lee, Wing-Sham; Rudd, Jason J; Kanyuka, Kostya

    2015-06-01

    Virus-induced gene silencing (VIGS) has emerged as a powerful reverse genetic technology in plants supplementary to stable transgenic RNAi and, in certain species, as a viable alternative approach for gene functional analysis. The RNA virus Barley stripe mosaic virus (BSMV) was developed as a VIGS vector in the early 2000s and since then it has been used to study the function of wheat genes. Several variants of BSMV vectors are available, with some requiring in vitro transcription of infectious viral RNA, while others rely on in planta production of viral RNA from DNA-based vectors delivered to plant cells either by particle bombardment or Agrobacterium tumefaciens. We adapted the latest generation of binary BSMV VIGS vectors for the identification and study of wheat genes of interest involved in interactions with Zymoseptoria tritici and here present detailed and the most up-to-date protocols. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  19. Effects of long term feeding of raw soya bean flour on virus-induced pancreatic carcinogenesis in guinea fowl.

    PubMed

    Kirev, T; Woutersen, R A; Kiril, A

    1999-01-29

    The effects of a diet enriched with 25% raw soya bean flour (RSF) on the pancreas and on the avian retrovirus Pts 56-induced pancreatic carcinogenesis in guinea fowl were studied. It has been shown that prolonged RSF feeding of new-hatched virus-infected and uninfected guinea fowl-poults induced enlargement of the pancreas, which was less pronounced when administration of the RSF supplemented diet started at the age of 75 days. Time-dependent multifocal inter- and intralobular hyperplasia of pleomorphic ducts lined by mucin-producing epithelium in the exocrine pancreas of virus-infected guinea fowls fed a RSF supplemented diet was regularly observed. Enlargement of virus-induced ductular neoplasms has been shown only after simultaneous RSF and virus administration.

  20. Virus induced gene silencing (VIGS) for functional analysis of wheat genes involved in Zymoseptoria tritici susceptibility and resistance

    PubMed Central

    Lee, Wing-Sham; Rudd, Jason J.; Kanyuka, Kostya

    2015-01-01

    Virus-induced gene silencing (VIGS) has emerged as a powerful reverse genetic technology in plants supplementary to stable transgenic RNAi and, in certain species, as a viable alternative approach for gene functional analysis. The RNA virus Barley stripe mosaic virus (BSMV) was developed as a VIGS vector in the early 2000s and since then it has been used to study the function of wheat genes. Several variants of BSMV vectors are available, with some requiring in vitro transcription of infectious viral RNA, while others rely on in planta production of viral RNA from DNA-based vectors delivered to plant cells either by particle bombardment or Agrobacterium tumefaciens. We adapted the latest generation of binary BSMV VIGS vectors for the identification and study of wheat genes of interest involved in interactions with Zymoseptoria tritici and here present detailed and the most up-to-date protocols. PMID:26092793

  1. [Observation of cells tolerant of tobacco mosaic virus in virus-induced local lesions in Datura stramonium L. leaves].

    PubMed

    Reunov, A V; Lega, S N; Nagorskaia, V P; Lapshina, L A

    2011-01-01

    Ultrastructural examination of tobacco mosaic virus-induced local lesions developing in leaves of Datura stramonium plants demonstrated that, in the central area of the lesions, the cell response to viral invasion was not uniform. Most cells exhibited an acute hypersensitive reaction and underwent rapid and complete necrosis. However, some cells, despite considerable virus accumulation and immediate contact with completely collapsed cells, maintained a certain degree of structural integrity. Analysis performed showed that the proportion of collapsed and uncollapsed cells in the lesion centre 3 to 5 days after infection did not change essentially. These data suggest that the absence of hypersensitive response in some cells in the lesion centre is not due to an early stage of infection but is likely caused by cell tolerance of the virus.

  2. Immune response to acute virus infection in the Syrian hamster. II. Studies on the identity of virus-induced cytotoxic effector cells

    SciTech Connect

    Nelles, M.J.; Duncan, W.R.; Streilein, J.W.

    1981-01-01

    The identity of the effector cell(s) mediating vaccinia virus-induced cytotoxic activity in Syrian hamsters undergoing acute virus infection has been investigated. Two different approaches have been utilized in this regard. Although T cells do not mediate vaccinia virus-induced cytotoxic activity directly, functional T cells were required for the in vivo development of a significant portion of vaccinia virus-induced cytotoxic activity. In addition, incorporation of aggregated gamma-globulins as well as anti-immunoglobulin reagents into the in vitro 51 Cr release assay inhibited a significant proportion of the cytotoxic activity mediated by spleen cells obtained from acutely infected hamsters possessing an intact thymus. Both approaches have yielded information consistent with the idea that a sizable portion of vaccinia virus-induced cytotoxic activity in the Syrian hamster is effected by K cells mediating antibody-dependent cell-mediated cytotoxicity (ADCC). The significance of this observation is discussed with regard to hamster viral immunity in general.

  3. PROGRESS IN ACUTE MYELOID LEUKEMIA

    PubMed Central

    Kadia, Tapan M.; Ravandi, Farhad; O’Brien, Susan; Cortes, Jorge; Kantarjian, Hagop M.

    2014-01-01

    Significant progress has been made in the treatment of acute myeloid leukemia (AML). Steady gains in clinical research and a renaissance of genomics in leukemia have led to improved outcomes. The recognition of tremendous heterogeneity in AML has allowed individualized treatments of specific disease entities within the context of patient age, cytogenetics, and mutational analysis. The following is a comprehensive review of the current state of AML therapy and a roadmap of our approach to these distinct disease entities. PMID:25441110

  4. A distinct epigenetic signature at targets of a leukemia protein

    PubMed Central

    Rossetti, Stefano; Hoogeveen, André T; Liang, Ping; Stanciu, Cornel; van der Spek, Peter; Sacchi, Nicoletta

    2007-01-01

    Background Human myelogenous leukemia characterized by either the non random t(8; 21)(q22; q22) or t(16; 21)(q24; q22) chromosome translocations differ for both their biological and clinical features. Some of these features could be consequent to differential epigenetic transcriptional deregulation at AML1 targets imposed by AML1-MTG8 and AML1-MTG16, the fusion proteins deriving from the two translocations. Preliminary findings showing that these fusion proteins lead to transcriptional downregulation of AML1 targets, marked by repressive chromatin changes, would support this hypothesis. Here we show that combining conventional global gene expression arrays with the power of bioinformatic genomic survey of AML1-consensus sequences is an effective strategy to identify AML1 targets whose transcription is epigenetically downregulated by the leukemia-associated AML1-MTG16 protein. Results We interrogated mouse gene expression microarrays with probes generated either from 32D cells infected with a retroviral vector carrying AML1-MTG16 and unable of granulocyte differentiation and proliferation in response to the granulocyte colony stimulating factor (G-CSF), or from 32D cells infected with the cognate empty vector. From the analysis of differential gene expression alone (using as criteria a p value < 0.01 and an absolute fold change > 3), we were unable to conclude which of the 37 genes downregulated by AML1-MTG16 were, or not, direct AML1 targets. However, when we applied a bioinformatic approach to search for AML1-consensus sequences in the 10 Kb around the gene transcription start sites, we closed on 17 potential direct AML1 targets. By focusing on the most significantly downregulated genes, we found that both the AML1-consensus and the transcription start site chromatin regions were significantly marked by aberrant repressive histone tail changes. Further, the promoter of one of these genes, containing a CpG island, was aberrantly methylated. Conclusion This study

  5. Treatment of prolymphocytic leukemia

    SciTech Connect

    Hollister, S. Jr.; Coleman, M.

    1982-11-01

    Prolymphocytic leukemia is characterized by marked splenomegaly, distinctive cellular morphologic characteristics, and a poor clinical course. Five patients with typical PL were treated systematically with vincristine/prednisone, chlorambucil/prednisone, splenic irradiation, splenectomy, and other chemotherapy regimens. No patient responded to vincristine/prednisone. Two patients responded to chlorambucil/prednisone, and four patients had brief responses to splenic irradiation. Two patients underwent splenectomy, one of whom had a prolonged clinical remissions. No other chemotherapy combinations were of value. The median survival was 33 months. Recommendations are made to use chlorambucil/prednisone or splenic irradiation as initial treatment. Splenectomy should be considered in patients refractory to these modalities. The course of PL may be more protracted than originally reported.

  6. Risk-Based Classification System of Patients With Newly Diagnosed Acute Lymphoblastic Leukemia

    ClinicalTrials.gov

    2017-02-13

    Adult B Acute Lymphoblastic Leukemia; Adult T Acute Lymphoblastic Leukemia; Childhood B Acute Lymphoblastic Leukemia; Childhood T Acute Lymphoblastic Leukemia; Untreated Adult Acute Lymphoblastic Leukemia; Untreated Childhood Acute Lymphoblastic Leukemia

  7. [Application of spectral karyotyping to cytogenetic analysis in acute myeloid leukemia].

    PubMed

    Guo, Bo; Zhu, Hong-Li; Li, Su-Xia; Han, Xiao-Ping; Sun, Jing-Fen; Wang, Li-Li; Huang, Wen-Rong; Da, Wan-Ming

    2011-07-01

    To evaluate the value of spectral karyotyping (SKY) in cytogenetic analysis of acute myeloid leukemias (AML). Nine AML patients were analyzed by R-banding and SKY. MLL, PML-RARalpha, AML1-ETO fusion genes were detected by dual fusion- fluorescence in situ hybridization (D-FISH). All 9 samples were successfully hybridized. SKY identified structural aberrations including 9q -, t(15;17) and ins(10;17) (q22;p11p12) ; and some numeral abnormalities. The results of SKY confirmed those of R-band karyotyping and D-FISH; with more accurate localization. SKY appears to be fairly stable, accurate and sensitive, for AML cytogenetic study.

  8. Induction and maintenance of DNA methylation in plant promoter sequences by apple latent spherical virus-induced transcriptional gene silencing

    PubMed Central

    Kon, Tatsuya; Yoshikawa, Nobuyuki

    2014-01-01

    Apple latent spherical virus (ALSV) is an efficient virus-induced gene silencing vector in functional genomics analyses of a broad range of plant species. Here, an Agrobacterium-mediated inoculation (agroinoculation) system was developed for the ALSV vector, and virus-induced transcriptional gene silencing (VITGS) is described in plants infected with the ALSV vector. The cDNAs of ALSV RNA1 and RNA2 were inserted between the cauliflower mosaic virus 35S promoter and the NOS-T sequences in a binary vector pCAMBIA1300 to produce pCALSR1 and pCALSR2-XSB or pCALSR2-XSB/MN. When these vector constructs were agroinoculated into Nicotiana benthamiana plants with a construct expressing a viral silencing suppressor, the infection efficiency of the vectors was 100%. A recombinant ALSV vector carrying part of the 35S promoter sequence induced transcriptional gene silencing of the green fluorescent protein gene in a line of N. benthamiana plants, resulting in the disappearance of green fluorescence of infected plants. Bisulfite sequencing showed that cytosine residues at CG and CHG sites of the 35S promoter sequence were highly methylated in the silenced generation zero plants infected with the ALSV carrying the promoter sequence as well as in progeny. The ALSV-mediated VITGS state was inherited by progeny for multiple generations. In addition, induction of VITGS of an endogenous gene (chalcone synthase-A) was demonstrated in petunia plants infected with an ALSV vector carrying the native promoter sequence. These results suggest that ALSV-based vectors can be applied to study DNA methylation in plant genomes, and provide a useful tool for plant breeding via epigenetic modification. PMID:25426109

  9. Contribution of virus-induced lysis and protozoan grazing to benthic bacterial mortality estimated simultaneously in microcosms.

    PubMed

    Fischer, Ulrike R; Wieltschnig, Claudia; Kirschner, Alexander K T; Velimirov, Branko

    2006-08-01

    In contrast to the water column, the fate of bacterial production in freshwater sediments is still a matter of debate. Thus, the importance of virus-induced lysis and protozoan grazing of bacteria was investigated for the first time simultaneously in a silty sediment layer of a mesotrophic oxbow lake. Microcosms were installed in the laboratory in order to study the dynamics of these processes over 15 days. All microbial and physicochemical parameters showed acceptable resemblance to field data observed during a concomitant in situ study, and similar conclusions can be drawn with respect to the quantitative impact of viruses and protozoa on the bacterial compartment. Viral decay rates ranged from undetectable to 0.078 h(-1) (average, 0.033 h(-1)), and the control of bacterial production from below the detection limit to 36% (average, 12%). The contribution of virus-induced lysis of bacteria to the dissolved organic matter pool as well as to benthic bacterial nutrition was low. Ingestion rates of protozoan grazers ranged from undetectable to 24.7 bacteria per heterotrophic nanoflagellate (HNF) per hour (average, 4.8 bacteria HNF(-1) h(-1)) and from undetectable to 73.3 bacteria per ciliate per hour (average, 11.2 bacteria ciliate(-1) h(-1)). Heterotrophic nanoflagellate and ciliates together cropped up to 5% (average, 1%) of bacterial production. The viral impact on bacteria prevailed over protozoan grazing by a factor of 2.5-19.9 (average, 9.5). In sum, these factors together removed up to 36% (average, 12%) of bacterial production. The high number of correlations between viral and protozoan parameters is discussed in view of a possible relationship between virus removal and the presence of protozoan grazers.

  10. Newcastle disease virus induces stable formation of bona fide stress granules to facilitate viral replication through manipulating host protein translation.

    PubMed

    Sun, Yingjie; Dong, Luna; Yu, Shengqing; Wang, Xiaoxu; Zheng, Hang; Zhang, Pin; Meng, Chunchun; Zhan, Yuan; Tan, Lei; Song, Cuiping; Qiu, Xusheng; Wang, Guijun; Liao, Ying; Ding, Chan

    2017-04-01

    Mammalian cells respond to various environmental stressors to form stress granules (SGs) by arresting cytoplasmic mRNA, protein translation element, and RNA binding proteins. Virus-induced SGs function in different ways, depending on the species of virus; however, the mechanism of SG regulation of virus replication is not well understood. In this study, Newcastle disease virus (NDV) triggered stable formation of bona fide SGs on HeLa cells through activating the protein kinase R (PKR)/eIF2α pathway. NDV-induced SGs contained classic SG markers T-cell internal antigen (TIA)-1, Ras GTPase-activating protein-binding protein (G3BP)-1, eukaryotic initiation factors, and small ribosomal subunit, which could be disassembled in the presence of cycloheximide. Treatment with nocodazole, a microtubule disruption drug, led to the formation of relatively small and circular granules, indicating that NDV infection induces canonical SGs. Furthermore, the role of SGs on NDV replication was investigated by knockdown of TIA-1 and TIA-1-related (TIAR) protein, the 2 critical components involved in SG formation from the HeLa cells, followed by NDV infection. Results showed that depletion of TIA-1 or TIAR inhibited viral protein synthesis, reduced extracellular virus yields, but increased global protein translation. FISH revealed that NDV-induced SGs contained predominantly cellular mRNA rather than viral mRNA. Deletion of TIA-1 or TIAR reduced NP mRNA levels in polysomes. These results demonstrate that NDV triggers stable formation of bona fide SGs, which benefit viral protein translation and virus replication by arresting cellular mRNA.-Sun, Y., Dong, L., Yu, S., Wang, X., Zheng, H., Zhang, P., Meng, C., Zhan, Y., Tan, L., Song, C., Qiu, X., Wang, G., Liao, Y., Ding, C. Newcastle disease virus induces stable formation of bona fide stress granules to facilitate viral replication through manipulating host protein translation.

  11. Interferon Gene Expression in Sputum Cells Correlates with the Asthma Index Score During Virus-Induced Exacerbations

    PubMed Central

    Schwantes, Elizabeth A.; Manthei, David M.; Denlinger, Loren C.; Evans, Michael D.; Gern, James E.; Jarjour, Nizar N.; Mathur, Sameer K.

    2014-01-01

    Rationale The majority of asthma exacerbations are related to viral respiratory infections. Some, but not all, previous studies have reported that low interferon responses in patients with asthma increase the risk for virus-induced exacerbations. Objective We sought to determine the relationship between lower airway inflammatory biomarkers, specifically interferon gene expression, and the severity or presence of an exacerbation in asthmatics experiencing a naturally occurring viral infection. Methods Sputum samples were analyzed from subjects in an asthma exacerbation study who experienced a confirmed viral infection. Subjects were monitored for daily symptoms, medication use, and peak expiratory flow rate until baseline. Sputum samples were assessed for cell counts and gene expression. Results IFN-γ expression was significantly greater in patients with asthma exacerbations compared to non-exacerbating patients (p=0.002). IFN-α1, IFN-β1, and IFN-γ mRNA levels correlated with the peak Asthma Index (r=0.58, p<0.001; r=0.57, p=0.001; and r=0.51, p=0.004, respectively). Additionally, IL-13, IL-10 and eosinophil major basic protein mRNA levels were greater in patients with asthma exacerbations compared to non-exacerbating patients (p=0.03, p=0.06, and p=0.02, respectively), and IL-13 mRNA correlated with the peak Asthma Index (p=0.006). Conclusions Our findings indicate that asthma exacerbations are associated with increased rather than decreased expression of interferons early in the course of infection. These findings raise the possibility that excessive virus-induced interferon production during acute infections can contribute to airway inflammation and exacerbations of asthma. PMID:24450586

  12. Targeting DOT1L and HOX gene expression in MLL-rearranged leukemia and beyond.

    PubMed

    Chen, Chun-Wei; Armstrong, Scott A

    2015-08-01

    Leukemias harboring mixed-lineage leukemia gene (MLL1) abnormalities are associated with poor clinical outcomes, and new therapeutic approaches are desperately needed. Rearrangement of the MLL1 gene generates chimeric proteins that fuse the NH3 terminus of MLL1 to the COOH terminus of its translocation partners. These MLL1 fusion oncoproteins drive the expression of homeobox genes such as HOXA cluster genes and myeloid ecotropic viral integration site 1 homolog (MEIS1), which are known to induce leukemic transformation of hematopoietic progenitors. Genomewide histone methylation studies have revealed that the abnormal expression of MLL1 fusion target genes is associated with high levels of H3K79 methylation at these gene loci. The only known enzyme that catalyzes methylation of H3K79 is disruptor of telomeric-silencing 1-like (DOT1L). Loss-of-function mouse models, as well as small molecular inhibitors of DOT1L, illustrate that leukemias driven by MLL1 translocations are dependent on DOT1L enzymatic activity for proliferation and for the maintenance of HOXA gene expression. Furthermore, DOT1L also appears to be important for HOXA gene expression in other settings including leukemias with select genetic abnormalities. These discoveries have established a foundation for disease-specific therapies that target chromatin modifications in highly malignant leukemias harboring specific genetic abnormalities. This review focuses on the molecular mechanisms underlying MLL1 translocation-driven leukemogenesis and the latest progress on DOT1L-targeted epigenetic therapies for MLL1-rearranged and other leukemias. Copyright © 2015 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.

  13. Antibody Therapy for Pediatric Leukemia

    PubMed Central

    Vedi, Aditi; Ziegler, David S.

    2014-01-01

    Despite increasing cure rates for pediatric leukemia, relapsed disease still carries a poor prognosis with significant morbidity and mortality. Novel targeted therapies are currently being investigated in an attempt to reduce adverse events and improve survival outcomes. Antibody therapies represent a form of targeted therapy that offers a new treatment paradigm. Monoclonal antibodies are active in pediatric acute lymphoblastic leukemia (ALL) and are currently in Phase III trials. Antibody-drug conjugates (ADCs) are the next generation of antibodies where a highly potent cytotoxic agent is bound to an antibody by a linker, resulting in selective targeting of leukemia cells. ADCs are currently being tested in clinical trials for pediatric acute myeloid leukemia and ALL. Bispecific T cell engager (BiTE) antibodies are a construct whereby each antibody contains two binding sites, with one designed to engage the patient’s own immune system and the other to target malignant cells. BiTE antibodies show great promise as a novel and effective therapy for childhood leukemia. This review will outline recent developments in targeted agents for pediatric leukemia including monoclonal antibodies, ADCs, and BiTE antibodies. PMID:24795859

  14. Materials research for fusion

    NASA Astrophysics Data System (ADS)

    Knaster, J.; Moeslang, A.; Muroga, T.

    2016-05-01

    Fusion materials research started in the early 1970s following the observation of the degradation of irradiated materials used in the first commercial fission reactors. The technological challenges of fusion energy are intimately linked with the availability of suitable materials capable of reliably withstanding the extremely severe operational conditions of fusion reactors. Although fission and fusion materials exhibit common features, fusion materials research is broader. The harder mono-energetic spectrum associated with the deuterium-tritium fusion neutrons (14.1 MeV compared to <2 MeV on average for fission neutrons) releases significant amounts of hydrogen and helium as transmutation products that might lead to a (at present undetermined) degradation of structural materials after a few years of operation. Overcoming the historical lack of a fusion-relevant neutron source for materials testing is an essential pending step in fusion roadmaps. Structural materials development, together with research on functional materials capable of sustaining unprecedented power densities during plasma operation in a fusion reactor, have been the subject of decades of worldwide research efforts underpinning the present maturity of the fusion materials research programme.

  15. Inhibition of Rac GTPases in the Therapy of Chronic Myelogenous Leukemia

    DTIC Science & Technology

    2009-04-01

    reported data and different outcome definitions, we could not perform a meta - analysis and thus, a final judgment about the influence of corticosteroids...myelogenous leukemia (CML) is a clonal myeloproliferative disease (MPD) characterized by the expression of the p210-BCR/ABL fusion gene [1]. This gene...components downstream of BCR/ABL. During the first year of this award, we reported our progress on the analysis of the role of Rac GTPases in

  16. 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

  17. Primary virus-induced lymphomas evade T cell immunity by failure to express viral antigens

    PubMed Central

    1989-01-01

    T lymphoma induction by the mink cell focus-inducing murine leukemia virus MCF 1233 in C57BL/10 and C57BL/6 mice is influenced by a strongly Th-dependent, H-2I-A-restricted antiviral immune response (25). We compared the MHC class I as well as viral env and gag antigenic cell surface profiles of frequent T lymphomas of H-2I-A nonresponder-type mice to that of rare T lymphomas of H-2I-A responder-type mice. Membrane immunofluorescence studies, with a panel of anti-env mAbs (reactive with the highly conserved gp70f epitope, the p15Ec epitope, and the gp70-p15E complex), a polyclonal anti-p30 serum, and anti-H-2 class I mAbs, showed that all 17 nonresponder tumors tested expressed high levels of both env and gag viral proteins, and 15 of these 17 nonresponder tumors expressed high levels of H-2 class I K and D antigens. In contrast, 10 of 11 responder lymphomas lacked env and/or gag determinants. The only responder lymphoma with both strong env and gag expression failed to express H-2K and -D antigens. Preferential loss of env or gag expression did not correlate with H-2 class I allelic specificities. Both responder and nonresponder T lymphoma DNA contained multiple, predominantly MCF-like, newly acquired proviral integrations. Differences in viral antigen cell surface expression were confirmed at cytoplasmic and RNA levels. The amounts of 8.2- and 3.2-kb viral RNA were greatly reduced in two responder lymphomas when compared with four nonresponder lymphomas. In both responder lymphomas, aberrantly sized viral RNA species were found. Upon in vivo passage of these responder lymphomas in either immunocompetent or T cell-deficient nu/nu mice, it was found that various molecular mechanisms may underlie the lack of viral antigen expression at the cell surface of these lymphomas. One lymphoma re-expressed viral antigens when transplanted with nu/nu mice, whereas the other remained stably gag negative. The combined findings indicate that an H-2I-A-regulated antiviral immune

  18. MLL-AF9 and MLL-ENL alter the dynamic association of transcriptional regulators with genes critical for leukemia.

    PubMed

    Monroe, Sara C; Jo, Stephanie Y; Sanders, Daniel S; Basrur, Venkatesha; Elenitoba-Johnson, Kojo S; Slany, Robert K; Hess, Jay L

    2011-01-01

    The aim of this study was to better understand how mixed lineage leukemia (MLL) fusion proteins deregulate the expression of genes critical for leukemia. The transforming domain of one of the most common MLL fusion partners, AF9, was immunopurified after expression in myeloblastic M1 cells, and associating proteins were identified by mass spectrometric analysis. Chromatin immunoprecipitation followed by quantitative polymerase chain reaction was used to determine how binding of associating proteins compare across Hoxa9 and Meis1 in cell lines with and without MLL fusion proteins and how binding is altered during gene down-regulation and differentiation. Consistent with earlier purifications of ENL and AF4 from 293 cells, the 90 amino acid C-terminal domain of AF9 associates with many other MLL translocation partners including Enl, Af4, Laf4, Af5q31, Ell, and Af10. This complex, termed elongation assisting proteins (EAPs), also contains the RNA polymerase II C-terminal domain kinase Cdk9/Cyclin T1/T2 (pTEFb) and the histone H3 lysine 79 methyltransferase Dot1L. Myeloid cells transformed by MLL fusions show higher levels and a broader distribution of EAP components at genes critical for leukemia. Inhibition of EAP components pTEFb and Dot1l show that both contribute significantly to activation of Hoxa9 and Meis1 expression. EAP is dynamically associated with the Hoxa9 and Meis1 loci in hematopoietic cells and rapidly dissociates during induction of differentiation. In the presence of MLL fusion proteins, its dissociation is prevented. The findings suggest that MLL fusion proteins deregulate genes critical for leukemia by excessive recruitment and impaired dissociation of EAP from target loci. Copyright © 2011 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.

  19. Dengue virus induces mitochondrial elongation through impairment of Drp1-triggered mitochondrial fission.

    PubMed

    Barbier, Vincent; Lang, Diane; Valois, Sierra; Rothman, Alan L; Medin, Carey L

    2017-01-01

    Mitochondria are highly dynamic organelles that undergo continuous cycles of fission and fusion to maintain essential cellular functions. An imbalance between these two processes can result in many pathophysiological outcomes. Dengue virus (DENV) interacts with cellular organelles, including mitochondria, to successfully replicate in cells. This study used live-cell imaging and found an increase in mitochondrial length and respiration during DENV infection. The level of mitochondrial fission protein, Dynamin-related protein 1 (Drp1), was decreased on mitochondria during DENV infection, as well as Drp1 phosphorylated on serine 616, which is important for mitochondrial fission. DENV proteins NS4b and NS3 were also associated with subcellular fractions of mitochondria. Induction of fission through uncoupling of mitochondria or overexpression of Drp1 wild-type and Drp1 with a phosphomimetic mutation (S616D) significantly reduced viral replication. These results demonstrate that DENV infection causes an imbalance in mitochondrial dynamics by inhibiting Drp1-triggered mitochondrial fission, which promotes viral replication.

  20. Mechanisms of Graft-vs.-Leukemia against a Novel Murine Model of Chronic Myelogenous Leukemia

    DTIC Science & Technology

    2006-07-01

    AD_________________ Award Number: DAMD17-03-1-0311 TITLE: Mechanisms of Graft-vs.- Leukemia ...against a Novel Murine Model of Chronic Myelogenous Leukemia PRINCIPAL INVESTIGATOR: Warren D. Shlomchik, M.D. CONTRACTING ORGANIZATION...5a. CONTRACT NUMBER Mechanisms of Graft-vs.- Leukemia against a Novel Murine Model of Chronic Myelogenous Leukemia 5b. GRANT NUMBER DAMD17