title: PML/RARalpha and FLT3-ITD induce an APL-like disease in a mouse model.
abstract: Acute promyelocytic leukemia (APL) cells invariably express aberrant fusion proteins involving the retinoic acid receptor alpha (RARalpha). The most common fusion partner is promyelocytic leukemia protein (PML), which is fused to RARalpha in the balanced reciprocal chromosomal translocation, t(15;17)(q22:q11). Expression of PML/RARalpha from the cathepsin G promoter in transgenic mice causes a nonfatal myeloproliferative syndrome in all mice; about 15% go on to develop APL after a long latent period, suggesting that additional mutations are required for the development of APL. A candidate target gene for a second mutation is FLT3, because it is mutated in approximately 40% of human APL cases. Activating mutations in FLT3, including internal tandem duplication (ITD) in the juxtamembrane domain, transform hematopoietic cell lines to factor independent growth. FLT3-ITDs also induce a myeloproliferative disease in a murine bone marrow transplant model, but are not sufficient to cause AML. Here, we test the hypothesis that PML/RARalpha can cooperate with FLT3-ITD to induce an APL-like disease in the mouse. Retroviral transduction of FLT3-ITD into bone marrow cells obtained from PML/RARalpha transgenic mice results in a short latency APL-like disease with complete penetrance. This disease resembles the APL-like disease that occurs with long latency in the PML/RARalpha transgenics, suggesting that activating mutations in FLT3 can functionally substitute for the additional mutations that occur during mouse APL progression. The leukemia is transplantable to secondary recipients and is ATRA responsive. These observations document cooperation between PML/RARalpha and FLT3-ITD in development of the murine APL phenotype.
authors.affiliation: Division of Hematology/Oncology, Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Louise M
authors.initials: LM
authors.lastname: Kelly
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Kutok
authors.forename: Ifor R
authors.initials: IR
authors.lastname: Williams
authors.forename: Christina L
authors.initials: CL
authors.lastname: Boulton
authors.forename: Sonia M
authors.initials: SM
authors.lastname: Amaral
authors.forename: David P
authors.initials: DP
authors.lastname: Curley
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Ley
authors.forename: D Gary
authors.initials: DG
authors.lastname: Gilliland
mesh_terms: D000818:Animals; D056649:Cathepsin G; D002403:Cathepsins / Q000235:genetics; D003433:Crosses, Genetic; D006801:Humans; D016130:Immunophenotyping; D015473:Leukemia, Promyelocytic, Acute / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D008565:Membrane Proteins / Q000235:genetics*; D051379:Mice; D008809:Mice, Inbred C3H; D008815:Mice, Inbred Strains; D008822:Mice, Transgenic; D009363:Neoplasm Proteins / Q000235:genetics*; D009368:Neoplasm Transplantation; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D012697:Serine Endopeptidases; D014212:Tretinoin / Q000494:pharmacology; D014410:Tumor Stem Cell Assay
chemical_list: D008565:Membrane Proteins; D009363:Neoplasm Proteins; D015514:Oncogene Proteins, Fusion; C084881:flt3 ligand protein; C093476:promyelocytic leukemia-retinoic acid receptor alpha fusion oncoprotein; D014212:Tretinoin; D002403:Cathepsins; D012697:Serine Endopeptidases; C534094:CTSG protein, human; D056649:Cathepsin G; C534096:Ctsg protein, mouse