1: Oncogene. 2002 Oct 17;21(47):7247-55. Large-scale identification of novel potential disease loci in mouse leukemia applying an improved strategy for cloning common virus integration sites. Joosten M, Vankan-Berkhoudt Y, Tas M, Lunghi M, Jenniskens Y, Parganas E, Valk PJ, Lowenberg B, van den Akker E, Delwel R. The Institute of Hematology, Erasmus University Rotterdam, Dr. Molewaterplein 50, 3015GE Rotterdam, The Netherlands. The identification of common virus integration sites (cVIS) in retrovirally induced tumors in mice provides a powerful strategy to isolate novel transforming genes. Applying virus LTR-specific inverse-PCR and RT-PCR combined with automated sequencing on CasBr-M Murine Leukemia Virus (MuLV) induced myeloid leukemias, 126 virus integration sites were cloned. Using locus- and LTR-specific primers, a nested-PCR/Southern-blotting procedure was developed on genomic DNA from a large panel of MuLV-induced leukemias, to analyse whether a particular virus insertion represented a cVIS. In fact 39 out of 41 integrations analysed this way appeared to represent a common virus integration. We recognized six previously cloned cVISs, i.e. Evi1, Hoxa7, c-Myb, Cb2/Evi11, Evi12, and His1 and 33 novel common insertions, designated Cas-Br Virus Integration Site (Casvis). Among this group we found integrations in or near genes encoding nuclear proteins, e.g. Dnmt-2, Nm23-M2, Ctbp1 or Erg, within receptor genes, e.g. Cb2 or mrc1, novel putative signaling or transporter genes, the ringfinger-protein gene Mid1 and a panel of genes encoding novel proteins with unknown function. The finding that 39 out of 41 integrations analysed represented a cVIS, suggests that the majority of the other virus insertions that were not yet analysed by the PCR/Southern-blotting method are located in a cVIS as well and may therefore also harbor novel disease genes. Publication Types: Evaluation Studies PMID: 12370816 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 2: Virology. 2000 Mar 15;268(2):308-18. Phenotyping of Evi1, Evi11/Cb2, and Evi12 transformed leukemias isolated from a novel panel of cas-Br-M murine leukemia virus-infected mice. Joosten M, Valk PJ, Vankan Y, de Both N, Lowenberg B, Delwel R. Institute of Hematology, Erasmus University Rotterdam, Rotterdam, 3000 DR, The Netherlands. Cas-Br-M murine leukemia virus (MuLV) is a slow-transforming retrovirus that potently induces leukemias in mice and therefore is well suited for retroviral insertional mutagenesis. We used Cas-Br-M MuLV in NIH/Swiss mice to establish a new panel of mainly myeloid leukemias. All tumors found in leukemic animals were classified by gross pathology, morphology, and immunophenotype, as well as the incidence of known common virus integration sites (VISs) in MuLV-induced myeloid malignancies (i.e., Evi1, Evi11/Cb2, Evi12, Fli1, and c-Myb). Interestingly, male mice were more susceptible than females to the induction of leukemia by Cas-Br-M MuLV. Seventy-four of the Cas-Br-M MuLV-inoculated mice developed a severe splenomegaly, sometimes in association with a thymoma. Although most of the immunophenotyped Cas-Br-M MuLV tumors were of myeloid origin (58%), numerous T-cell leukemias (21%) and mixed myeloid/T-cell leukemias (21%) were found. The myeloid leukemias and myeloid compartment of the mixed leukemias were further characterized by immunophenotyping with stem cell-, myeloid-, and erythroid-specific antibodies. The known Cas-Br-M MuLV common VISs (Evi1, Evi11/Cb2, and Evi12) were demonstrated in 19%, 12%, and 20% of the cases, respectively, whereas no Fli1 and c-Myb rearrangements were found. Integrations into Evi1 were restricted to myeloid leukemias, whereas those in Evi11/Cb2 and Evi12 were identified in myeloid as well as T-lymphoid leukemias. This panel of well characterized Cas-Br-M MuLV-induced hematopoietic tumors may be useful for the isolation and characterization of new proto-oncogenes involved in myeloid or T-cell leukemias. Copyright 2000 Academic Press. PMID: 10704339 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 3: Genomics. 1996 Oct 1;37(1):24-8. The B-lymphocyte maturation promoting transcription factor BLIMP1/PRDI-BF1 maps to D6S447 on human chromosome 6q21-q22.1 and the syntenic region of mouse chromosome 10. Mock BA, Liu L, LePaslier D, Huang S. National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA. The human PRDI-BF1 or BLIMP1 gene and its mouse homolog Blimp1 are members of the recently realized PR domain family that includes the retinoblastoma interacting zinc finger gene RIZ and the MDS1-EVI1 leukemia cancer gene. The specific high-level expression of Blimp1 in late B and plasma cells, its induction during B-cell differentiation, and its ability to drive B-cell maturation suggest that this gene may play a role in the differentiation and pathogenesis of B cells. We have now mapped the physical location of BLIMP1 near the marker D6S447 on human chromosome 6q21-q22.1; we have also mapped Blimp1 to mouse Chromosome 10 at 14 cM distal to the Myb locus and to a region homologous to the location of BLIMP1. Deletions of the 6q21-q22 region are common in several human malignancies, particularly in B-cell non-Hodgkin lymphoma (B-NHL). The data led us to suggest that BLIMP1 may be a candidate B-NHL tumor suppressor gene. PMID: 8921366 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 4: Mol Cell Biol. 1994 Aug;14(8):5558-68. PEBP2/CBF, the murine homolog of the human myeloid AML1 and PEBP2 beta/CBF beta proto-oncoproteins, regulates the murine myeloperoxidase and neutrophil elastase genes in immature myeloid cells. Nuchprayoon I, Meyers S, Scott LM, Suzow J, Hiebert S, Friedman AD. Division of Pediatric Oncology, Johns Hopkins Oncology Center, Johns Hopkins University, Baltimore, Maryland 21287. The myeloperoxidase (MPO) and neutrophil elastase genes are expressed specifically in immature myeloid cells. The integrity of a polyomavirus enhancer core sequence, 5'-AACCACA-3', is critical to the activity of the murine MPO proximal enhancer. This element binds two species, myeloid nuclear factors 1 alpha and 1 beta (MyNF1 alpha and -beta), present in 32D cl3 myeloid cell nuclear extracts. The levels of the MyNF1s increase during early 32D cl3 cell granulocytic differentiation. Both MyNF1 alpha and -beta supershift with an antiserum raised by using a peptide derived from the N terminus of polyomavirus enhancer-binding protein 2/core-binding factor (PEBP2/CBF) alpha subunit. The specific peptide inhibits these supershifts. In vitro-translated PEBP2/CBF DNA-binding domain binds the murine MPO PEBP2/CBF site. An alternate PEBP2/CBF consensus site, 5'-GACCGCA-3', but not a simian virus 40 enhancer core sequence, 5'-TTCCACA-3', binds the MyNF1s in vitro and activates a minimal murine MPO-thymidine kinase promoter in vivo. The murine neutrophil elastase gene 100-bp 5'-flanking sequences contain several functional elements, including potential binding sites for PU.1, C/EBP, c-Myb, and PEBP2/CBF. The functional element 5'-GGCCACA-3' located at positions -66 to 72 differs from the PEBP2/CBF consensus (5'-PuACCPuCA-3') only by an A-to-G transition at position 2. This DNA element binds MyNF1 alpha and -beta weakly. The N terminis of two PEBP2/CBF alpha subunit family members, PEBP2 alpha A and PEBP2 alpha B (murine AML1), are nearly identical, and 32D c13 cl3 cells contain both corresponding mRNAs. Since t(8;21), t(3;21), and inv(16), associated with myeloid leukemias, disrupt subunits of PEBP2/CBF, we speculate that the resulting oncoproteins, AML1-ETO, AML1-EAP, AML1-Evi1, and CBF beta-MYH11, inhibit early myeloid differentiation. PMID: 8035830 [PubMed - indexed for MEDLINE] --------------------------------------------------------------- 5: Prog Clin Biol Res. 1990;352:329-37. Insertional mutagenesis and transformation of hematopoietic stem cells. Ihle JN, Morishita K, Matsugi T, Bartholomew C. Department of Biochemistry, St. Jude Children's Research Hospital, Memphis, TN 38105. The mechanisms that are involved in the control of the normal differentiation of hematopoietic progenitor cells are largely unknown. Moreover, little is known concerning the types of genes that can alter the ability of hematopoietic progenitors to differentiate and cause transformation. One approach to the latter has been to use retroviral induced IL-3-dependent myeloid leukemia cell lines to identify transforming genes by their activation through insertional mutagenesis. This approach has implicated alterations in c-myb in transformation and has identified a novel transcriptional factor of the zinc finger family that is frequently activated in murine myeloid leukemias and in some cases of human AML. Using this approach it should be possible to identify additional myeloid transforming genes. The identification and characterization of the genes will provide important information and approaches to the study of the regulation of differentiation in normal hematopoiesis. PMID: 2169632 [PubMed - indexed for MEDLINE] ---------------------------------------------------------------