title: Leukemic cells from murine myeloid leukemia display an intrinsic ability for autonomous proliferation.
abstract: OBJECTIVE
  Human acute myeloid leukemia (AML) cells can proliferate in vitro in the absence of added growth factors when cultured at high cell density. Autocrine growth factor production is a postulated mechanism of autonomous growth. We sought to examine this using murine AML cells.
  
  
  METHODS
  We have utilized a Moloney murine leukemia virus (M-MuLV) model of AML to investigate the nature of autonomous in vitro growth of myeloid leukemic cells.
  
  
  RESULTS
  Like human AML, M-MuLV-induced myeloid leukemic cells displayed autonomous growth in unstimulated high cell density cultures. However, replating of individual, primary, growth factor autonomous colonies of leukemic cells demonstrated the presence of clonogenic cells capable of autonomous growth when cultured at low cell density. In addition, there was heterogeneity in the progeny of these cells: both factor-dependent leukemic cells and cells autonomous of exogenous factor were observed.
  
  
  CONCLUSIONS
  We propose that clonogenic cells capable of autonomous growth at low cell density represent leukemic progenitors while the majority of leukemic cells derived from these "autonomous" leukemic cells are factor-dependent.
authors.affiliation: The Walter and Eliza Hall Institute of Medical Research, Royal Melbourne Hospital, Victoria, Australia.
authors.forename: D J
authors.initials: DJ
authors.lastname: Curtis
authors.forename: D
authors.initials: D
authors.lastname: Metcalf
authors.forename: B
authors.initials: B
authors.lastname: Alexander
authors.forename: C G
authors.initials: CG
authors.lastname: Begley
mesh_terms: D000208:Acute Disease; D000818:Animals; D001202:Ascitic Fluid / Q000166:cytology; D002452:Cell Count; D002455:Cell Division; D017077:Culture Media, Conditioned / Q000378:metabolism; D005260:Female; D016179:Granulocyte Colony-Stimulating Factor / Q000096:biosynthesis; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000096:biosynthesis; D016130:Immunophenotyping; D007377:Interleukin-3 / Q000096:biosynthesis; D015850:Interleukin-6 / Q000096:biosynthesis; D007951:Leukemia, Myeloid / Q000378:metabolism / Q000473:pathology*; D016173:Macrophage Colony-Stimulating Factor / Q000096:biosynthesis; D051379:Mice; D008807:Mice, Inbred BALB C; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured; D014410:Tumor Stem Cell Assay
chemical_list: D017077:Culture Media, Conditioned; D007377:Interleukin-3; D015850:Interleukin-6; D012333:RNA, Messenger; D016179:Granulocyte Colony-Stimulating Factor; D016173:Macrophage Colony-Stimulating Factor; D016178:Granulocyte-Macrophage Colony-Stimulating Factor