2. CLINICAL SCIENCE

SEMINAR REPORT

  1. Title of Seminar: Animal models for hematological malignancies and hematopoiesis
  2. Period: March 22 to March 26, 2005, 5 days
  3. Site: Hawaii ( Maui island ), U.S.A.
  4. Japanese Organizer: Takuro Nakamura (Chief, The Cancer Institute, Department of Carcinogenesis, Japanese Foundation for Cancer Research)
  5. US Organizer: Thomas A. Look (Professor, Department of Pediatric Oncology, Dana-Farber Cancer Institute)
  6. List of Japanese-side Participants

    Kazuo Kitabayashi
    Chief
    National Cancer Center Research Institute

    Kinuko Mitani
    Professor
    Dokkyo University School of Medicine

    Masayuki Yamamoto
    Professor
    Center for TARA, University of Tsukuba

    Hiromitsu Nakauchi
    Professor
    Institute of Medical Science,

    eishi Ogawa
    Associate Professor
    Tokyo University Graduate School of Medicine

    Satoru Takahashi
    Professor
    Institute of Basic Medical Sciences,
    University of Tsukuba

    Yuji Yamanashi
    Professor
    Medical Research Institute,
    Tokyo Medical and Dental University

    Ryo Kominami
    Professor
    Graduate School of Medical and
    Dental Sciences, Niigata University

    Takeshi Suzuki
    Associate Professor
    Kyoto University Faculty of Medicine

    Yuzuru Kanakua
    Professor
    Osaka University Graduate School of Medicine

  7. List of US-side Participants

    Nancy Speck
    Professor
    Dartmouth-Hitchcock Medical Center

    Dong-ErZhang
    Assosiate Professor
    The Scripps Research Institute

    Michelle Kelliher
    Assosiate Professor
    University of Massachusetts Medical School

    Pier Paolo Pandolfi
    Professor
    Memorial Sloan-Kettering Cancer Center

    Michael Cleary
    Professor
    Stanford University School of Medicine

    Riccardo Dalla-Favera
    Professor
    Columbia University

    Leonard I. Zon
    Professor
    Children's Hospital Boston

    Dean Felsher
    Assistant Professor
    Stanford University School of Medicine

  8. List of Other Country Participants

    Yoshiaki Ito
    Professor
    Institute of Molecular and CellularBiology, Singapore

    Motomi Osato
    Research Assistant Professor
    Institute of Molecular and CellularBiology, Singapore

  9. Agenda and Topics
    Monday, March 21: Arrival and Hotel check-in
    Tuesday, March 22
    Session I   Myeloid leukemias
    8:00-8:45 Nancy Speck: Core binding factor mutations in hematopoietic disease
    8:45-9:30 Motomi Osato, Yoshiaki Ito: Multistep carcinogenesis in RUNX1-related leukemias
    9:30-10:15 Kinuko Mitani: In vivo function of AML1/Evi-1 chimeric gene
    10:45-11:30 Pier Paolo Pandolfi: The role of Pokemon in human malignancy
    11:30-12:15 Masayuki Yamamoto: Hematopoietic malignancies related to GATA transcription factors
    Wednesday, March 23
    Session II   Stem cells and leukemia
    13:00-13:45 Hiromitsu Nakauchi: Massive expansion of HSC in Lnk-deficient mice
    13:45-14:30 Leonard I. Zon: Stem cell development in the zebrafish
    14:30-15:15 Dean Felsher: Reversing hematopoietic tumorigenesis
    15:45-16:30 Micheal Cleary: At the intersection of MLL and Menin; what does it mean for leukemia
    16:30-17:15 Issay Kitabayashi: Functional analysis of the AML1 transcription factor complex
    17:15-18:00 Yuzuru Kanakura: Role of anti-apoptotic molecule Anamorsin in hematopoiesis and hematological malignancies
    Thursday, March 24
    Session III   T cell lymphoid malignancies
    8:00-8:45 Ryo Kominami: Functional role of Rit1/Bcl11b in the development of mouse thymic lymphoma
    8:45-9:30 Michelle Kelliher: Cooperating mutations in a mouse model of TAL1/SCL- induced leukemia
    9:30-10:15 A. Thomas Look: Genetics of T-cell ALL: the role of Notch
    10:45-11:30 Shigeru Chiba: Notch signaling: role in an unexpected blood lineage
    11:30-12:15 Satoru Takahashi: Functional analysis of large Maf transcription factors for development of multiple myeloma and T cell lymphoma by using transgenic mouse model
    12:15-13:00 Riccardo Dalla-Favera: The role of BCL6 in diffuse large cell lymphoma
    Friday, March 25
    Session IV   Myeloid leukemias
    8:00-8:45 Seishi Ogawa: Inactivation of the c-cbl gene promotes tumor generation
    8:45-9:30 Takuro Nakamura: Analysis of Evi9/Bcl11a-induced leukemia using a mouse model
    9:30-10:15 Takeshi Suzuki: Retroviral tagging of candidate tumor suppressor genes from MuLV-infected mice with genome instability
    10:45-11:30 Yuji Yamanashi: Role of Dok-family adaptors in hematopoietic cells
    11:30-12:15 Dong-Er Zhang: UBP43, a protease for ubiquitin-like modifier ISG15, in interferon signaling and leukemia development
    Saturday, March 26
    Session V   Discussion Session
    8:00-10:15 Stem cells in leukemia: Basic and clinical implications
  10. Scientific Achievements
    1. Stem cell
      1. Lnk knockout (ko) homozygous mice have high stem cell activity in the bone marrow. Bone marrow transfer (BMT) of Lnk -/- mice outcompeted the wild type bone marrow cells with 5 to 60-fold increase of the stem cell activity.
      2. Runx1 is required for definitive but not for primitive hematopoiesis of zebrafish. Constitutive activation of notch intracellular domain (ICN) results in increase of hematopoietic stem cell (HSC) by converting endothelial cells to HSC.
    2. Transcription factor
      1. The RUNX1 HHR domain is important for protein-protein interaction and its mutant lost the replating activity. Runt domain mutations in RUNX1 were found in human AML.
      2. The heterozygous AML1-EVI1 knock-in mice showed similar phenotype to the AML1 ko homozygotes and AML1-ETO knock-in heterozygotes. Only CFU-M and CFU-GEMM were seen in the fetal liver cell of AML1-EVI1 knock-in embryos. PU.1 expression was preserved in AML1-EVI1 knock-in, which may explain phenotypic difference from AML1 ko.
      3. Pokemon ko homozygotes showed differentiation block of pro-B-cells and promyelocytes, and no cell cycle progression was seen in erythroblasts. Pokemon transgenic (tg) mice developed T-cell lymphoma, repressing the arf promoter. Pokemon was overexpressed in various human cancers and may be a good target for HDAC inhibitors.
      4. Erythropoiesis was suppressed and myeloid progenitors were decreased in the homozygous MOZ mutant. MOZ -/- bone marrow cells could not compete wild type bone marrow cells. Phosphorylation of p300, AML1/2/3, PU.1, c-myb, jun and fos are HIPK2 dependent. Vasculogenesis, angiogenesis and definitive hematopoiesis was inhibited in the HIPK1/HIPK2 double ko homozygous mutant mice.
    3. Leukemogenesis/Lymphomagenesis
      1. The tetracycline-inducible system exhibited regression lymphoma in myc tg mice by erasing myc expression but the tumor frequently relapsed. Relapsed tumors were myc-independent and acquired novel translocation at chromosome 3. myc overexpression induced genomic instability and myc inactivation restored DNA repair. Statin prevented tumorigenesis by inhibiting myc phosphorylation.
      2. Translocation of ICN needs both metalloprotease and γ-secretase. The PEST domain in the notch C-terminus decreases half time. Mutations of HD, the target of γ-secretase, and PEST mutations were seen in human T-cell leukemia (58% in pediatric T-ALL).
      3. TAL1/SCL tg mice using the lck promoter developed T-cell leukemia. E2A +/- or HEB+/- background accelerated the disease in TAL1 tg mice, and T-cell development was perturbed in these mice. Notch1 was a common insertion site in MoMLV-infected TAL1 tumors with ICN, Hes1 and Deltex upregulation. Tumors in TAL1 tg mice were sensitive to γ-secretase inhibitiors that downregulate the notch signaling.
      4. DNA damaging agents such as etoposide downregulated BCL6 via the proteasome/ubiquitin pathway. Constitutive expression of BCL6 protected cells from DNA damage-induced apoptosis in diffuse large B-cell lymphoma (DLBCL) cells. The mice with BCL6 knock-in into the Ig μenhancer showed aberrant BCL6 expression in post-germinal center B-cells, and germinal centers were increased in number. The mice developed lymphoproliferative disease and DLBCL eventually.
      5. Loss of Bcl11a/Evi9 inhibited B-cell development at the pro-B stage, and Bcl11a and E2A synergistically activated the Ig μ enhancer. BMT using Bcl11a-transduced cells induced T-cell lymphoma in the cell non-autonomous manner.
      6. T cell development was blocked at the DN3 stage in the Rit1/Bcl11b homozygous ko mice. Bcl11b ko +/- was more susceptible to radiation- and MNU-induced lymphomagenesis, and spontaneous lymphoma was seen in the Bcl11b +/- p53 -/- mice, indicating that Bcl11b is haploinsufficient to T-cell lymphoma development.
      7. Retroviral insertional mutagenesis using Bloom mutant background identified tumor suppressors including Rbl1, Rbl2, Cdkn2c, Fancg, Fbxl10, Fbxl11 and 3110005o21Rik.
  11. Other Seminar Activities: None
  12. Comments and Opinions
    The seminar on "Animal models of Hematological Malignancies and Hematopoiesis" was held in support by National Cancer Institute of US and Japan Society for the Promotion of Science from March 21 to March 26 at Maui Prince Hotel in Maui island of Hawaii. There were more than 20 American and Japanese scientists who were selected on the basis of their expertise and interests as most likely to contribute to a stimulating and productive environment. Major focus was on a variety of animal models that are being used to define the biological roles of cellular oncogenes implicated in the development of specific leukemias and lymphomas. Presentation of participants was fantastick, and novel data that had not been published anywhere were presented.
    Among the topics discussed were: functional dissection of RUNX1 and its oncogenic form AML1-EVI1 in hematopoiesis and leukemogenesis, oncogenic function of POKEMON and its aberrant expression in human malignancies, functional and mutation analysis of notch molecule in lymphomagenesis, tumor regression model by reversible expression of oncogenes, functional role of Bcl11 family genes in lymphomagenesis, development of plasmacytoma and T-cell lymphoma in c-maf transgenic mice, development of diffuse large B-cell lymphoma in the Bcl6 knock-in mouse into immunoglobulin ? enhancer, and recent advances in retroviral insertional mutagenesis. Substantial parts of the studies were achieved using animal models, and these models were excellently devised to develop appropriate tumors that exhibit similar molecular profiles as human counterparts.
    It should be noted that there were fruitful and very productive discussions through the meeting sessions, and every participants had a feeling that exchanging the scientific data and information was incredibly useful. Collaborative researches will be taken place, for instance, there have been already collaborations between Dr. Pandolfi and Dr. Kitabayashi for PML/RUNX1 interaction, and between Dr. Speck and Dr. Mitani for RUNX1 function.
    At last, all the US and Japanese participans were very disappointed to know that the seminar under the US-Japan Cooperative Cancer Research Program would not be held any longer. The seminar provides a unique opportunity and this is an exceptionally successful meeting. We would ask NCI and JSPS to promote scientific seminars for cancer research.