title: Expressions and clinical significance of factors related to giant cell tumor of bone.
abstract: BACKGROUND
  Giant cell tumor of bone (GCTB) is a relatively rare tumor of bone, characterized by numerous multinucleated cells, severe osteolysis, and local recurrence.
  
  
  OBJECTIVE
  To explore the role of S-phase kinase-interacting protein 2 (Skp2), cyclin-dependent kinase inhibitor p27, and the transcription factor E2F-1 expression in the development of GCTB, and the relationship of expression of these proteins with tumor recurrence.
  
  
  METHODS
  Forty-four patients with GCTB were selected and demographic and clinical data were collected. The levels of Skp2, p27, and E2F-1 protein expression were immunohistochemically assessed in surgical specimens.
  
  
  RESULTS
  Skp2, p27, and E2F-1 proteins were detected in the nuclei of mononuclear stromal cells. Positive Skp2 expression was observed in 66% (29/44) of GCTB patient samples, and positive p27 expression was found in 39% (17/44) of samples. Within almost all GCTB patients, there was an inverse correlation between Skp2- and p27-positive tumor cells. Positive expression of E2F-1 was present in 28 of 44 (64%) patients. In addition, expression of skp2 and p27, infiltration of soft tissues, and surgical operation were significantly associated with recurrence in patients with GCTB.
  
  
  CONCLUSIONS
  The immunohistochemical assessment of Skp2, p27 and E2F-1 may be useful in the diagnosis of GCTB and prediction of its prognosis.
authors.affiliation: Department of Orthopedics, The Second Affiliated Hospital of Soochow University Suzhou 215004, Jiangsu, China.
authors.forename: Chong
authors.initials: C
authors.lastname: Li
authors.affiliation: Department of Pathology, The First People's Hospital of Kunshan, Jiangsu University Suzhou 215300, Jiangsu, China.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Department of Surgery, McMaster University Hamilton, ON, Canada.
authors.forename: Michelle
authors.initials: M
authors.lastname: Ghert
authors.affiliation: Department of Pathology, The First People's Hospital of Kunshan, Jiangsu University Suzhou 215300, Jiangsu, China.
authors.forename: Hai
authors.initials: H
authors.lastname: Li
authors.affiliation: Laboratory Center, The First People's Hospital of Kunshan, Jiangsu University Kunshan 215300, Jiangsu, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Pathology, The Second Affiliated Hospital of Soochow University Suzhou 215004, Jiangsu, China.
authors.forename: Yizhong
authors.initials: Y
authors.lastname: Feng
keywords: E2F-1; GCTB; Skp2; expression; p27; recurrence