title: Lineage switch in childhood leukemia with monosomy 7 and reverse of lineage switch in severe combined immunodeficient mice.
abstract: Morphophenotypic lineage switches occur in a small percentage of those with acute leukemia, and the underlying mechanisms are not clear. In this study, we attempted to induce a lineage switch in acute myelocytic leukemia (AML) with monosomy 7, whose lineage had switched from acute T-lymphocytic leukemia (T-ALL) during chemotherapy, in severe combined immunodeficient (SCID) mice. Although the transplanted myeloid cells were engrafted in SCID mice without cytokine administration, T-ALL developed in SCID mice treated with recombinant human granulocyte-macrophage colony-stimulating factor or recombinant human interleukin 3. Analysis of the nucleotide sequences of the rearranged T-cell receptor gamma-chain (TCR-gamma) gene revealed that this lineage switch resulted from the selection of the T-lineage subclone in SCID mice, which had expanded at onset. In addition, we found that the T-lineage and myeloid cells belonged to the distinct subclones, which were different in TCR-gamma gene rearrangements, but were derived from a common clone with an identical N-ras gene mutation for both subclones. In in vitro cultures, only the myeloid subclone grew; the T-lineage subclone failed to grow even in the presence of recombinant human granulocyte-macrophage colony-stimulating factor or recombinant human interleukin 3. These results suggested that the initial diagnostic T-lymphoid subclone, whose growth was dependent on these cytokines and the hematopoietic microenvironment, emerged from a bipotential T-lymphoid/myeloid leukemic stem cell, and further genetic event(s) induced the myeloid subclone, which grew independently of these cytokines and the microenvironment.
authors.affiliation: Department of Pediatrics, Faculty of Medicine, Osaka University, Suita, Japan. fujisaki@ped.med.osaka-u.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Fujisaki
authors.forename: J
authors.initials: J
authors.lastname: Hara
authors.forename: K
authors.initials: K
authors.lastname: Takai
authors.forename: K
authors.initials: K
authors.lastname: Nakanishi
authors.forename: Y
authors.initials: Y
authors.lastname: Matsuda
authors.forename: H
authors.initials: H
authors.lastname: Ohta
authors.forename: Y
authors.initials: Y
authors.lastname: Osugi
authors.forename: S
authors.initials: S
authors.lastname: Tokimasa
authors.forename: M
authors.initials: M
authors.lastname: Taniike
authors.forename: G
authors.initials: G
authors.lastname: Hosoi
authors.forename: M
authors.initials: M
authors.lastname: Sako
authors.forename: S
authors.initials: S
authors.lastname: Okada
mesh_terms: D000208:Acute Disease; D000818:Animals; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001483:Base Sequence; D019070:Cell Lineage; D002675:Child, Preschool; D002897:Chromosomes, Human, Pair 7; D004273:DNA, Neoplasm; D015334:Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006801:Humans; D007377:Interleukin-3 / Q000494:pharmacology; D007621:Karyotyping; D007951:Leukemia, Myeloid / Q000235:genetics / Q000473:pathology*; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000188:drug therapy / Q000235:genetics / Q000473:pathology*; D008297:Male; D051379:Mice; D016513:Mice, SCID; D008969:Molecular Sequence Data; D009006:Monosomy; D009368:Neoplasm Transplantation; D011994:Recombinant Proteins / Q000494:pharmacology; D014407:Tumor Cells, Cultured
chemical_list: D004273:DNA, Neoplasm; D007377:Interleukin-3; D011994:Recombinant Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor