title: Stro-1(+)  stromal cells have stem-like features in giant cell tumor of bone.
abstract: BACKGROUND
  Giant cell tumor of bone (GCTB) is an aggressive benign bone tumor with poor prognosis whose neoplastic component is stromal cells (SCs). Tumor stem-like cells (TSCs) have been demonstrated as precursors for tumor genesis and growth. The aim of this study is to identify TSCs in GCTB.
  
  
  METHODS
  Stro-1(+) and Stro-1(-) cells were isolated by fluorescence-activated cell sorting (FACS). Stem-like properties of both Stro-1(+) and Stro-1(-) subpopulations were assessed using MTT colorimetric assays, cell cycle analyses, sphere formation assays, and differentiation assays. Molecular profiles were analyzed by flow cytometry, immunofluorescence, and qRT-PCR.
  
  
  RESULTS
  The existence of rare Stro-1(+) cells was confirmed in vitro using FACS and in vivo by immunohistochemistry. These Stro-1(+) cells exhibited higher proliferative and cisplatin-resistant potentials than Stro-1(-) cells. In serum-free suspension cultures, Stro-1(+) SCs could form cell spheres and maintain self-renewal. Furthermore, Stro-1(+) SCs could differentiate into two mesenchymal lineage cells: osteoblasts and adipocytes. Cell surface markers CD44, CD117, and CD133 and stem cell-associated genes OCT3/4, NANOG, and ABCG2 were significantly higher in the Stro-1(+) subpopulation.
  
  
  CONCLUSIONS
  This study demonstrates that Stro-1(+) SCs in GCTB possess stem-like biological and molecular phenotypes, indicating that they are the TSCs of GCTB.
authors.affiliation: Department of Orthopaedics, Peking University Third Hospital, Beijing, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Lan
authors.forename: Xiaoguang
authors.initials: X
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Rong
authors.forename: Feng
authors.initials: F
authors.lastname: Wei
authors.forename: Liang
authors.initials: L
authors.lastname: Jiang
authors.forename: Haiyan
authors.initials: H
authors.lastname: Yu
authors.forename: Gengting
authors.initials: G
authors.lastname: Dang
authors.forename: Zhongjun
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000954:Antigens, Surface / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D001859:Bone Neoplasms / Q000378:metabolism / Q000473:pathology*; D002453:Cell Cycle / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation; D018212:Giant Cell Tumor of Bone / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D014411:Neoplastic Stem Cells / Q000502:physiology*; D017154:Stromal Cells / Q000166:cytology* / Q000502:physiology*
chemical_list: D000954:Antigens, Surface; D015415:Biomarkers; C525591:STRO-1 antigen, human