title: The expression and clinical significance of HDGF in osteosarcoma.
abstract: OBJECTIVE
  To investigate the expression of hepatoma-derived growth factor (HDGF) in osteosarcoma (OS) and the correlation with clinicopathologic factors, prognosis, and tumor progression.
  
  
  METHODS
  HDGF expression in OS tissues was detected by immunohistochemistry. The correlation between HDGF and clinicopathologic factors was analyzed by chi-square test, and the association between HDGF expression and the overall survival rates was evaluated by univariate analysis using Kaplan-Meier method. HDGF concentration in cell medium or cell lysates was detected by enzyme-linked immunosorbent assay method. The effect of extrinsic and intrinsic HDGF on OS cell proliferation was detected by MTT assay after recombinant HDGF stimulation or HDGF knockdown, respectively.
  
  
  RESULTS
  Proportion of HDGF high expression was 18.69% (20/107) in OS. HDGF high expression was significantly associated with larger tumor size (P=0.004). With experiments in vitro, we demonstrated that human recombinant HDGF could activate AKT and MAPK signaling pathway, resulting in OS cell proliferation. By knocking down HDGF expression, we proved that intrinsic HDGF was required in OS proliferation.
  
  
  CONCLUSIONS
  High HDGF expression was significantly associated with larger OS tumor size and could promote OS cell proliferation, indicating that HDGF could be an effective biomarker and a potential drug target in OS treatment.
authors.affiliation: Department of Orthopedics, Linyi People's Hospital, Linyi City, Shandong Province, People's Republic of China.
authors.forename: Zhiguo
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Orthopedics, People's Hospital of Taiyuan, Taiyuan City, Shanxi Province, People's Republic of China.
authors.forename: Shenghai
authors.initials: S
authors.lastname: Qiu
authors.affiliation: Department of General Surgery, Jinan Central Hospital affiliated to Shandong University, Jinan City, Shandong Province, People's Republic of China.
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Lu
keywords: hepatoma-derived growth factor; osteosarcoma; overall survival rate; proliferation; tumor size