title: Expression of vascular endothelial growth factor in cultured human dental follicle cells and its biological roles.
abstract: OBJECTIVE
  To investigate the expression of vascular endothelial growth factor (VEGF) in cultured human dental follicle cells (HDFC), and to examine the roles of VEGF in the proliferation, differentiation, and apoptosis of HDFC in vitro.
  
  
  METHODS
  Immunocytochemistry, ELISA, and RT-PCR were used to detect the expression and transcription of VEGF in cultured HDFC. The dose-dependent and the time-course effect of VEGF on cell proliferation and alkaline phosphatase (ALP) activity in cultured HDFC were determined by MTT assay and colorimetric ALP assay, respectively. The effect of specific mitogen-activated protein kinase (MAPK) inhibitors (PD98059 and U0126) on the VEGF-mediated HDFC proliferation was also determined by MTT assay. The effect of VEGF on HDFC apoptosis was measured by flow cytometry.
  
  
  RESULTS
  VEGF was transcribed and expressed in cultured HDFC. VEGF at 10-300 microg/L significantly increased HDFC proliferation and ALP activity compared to the control. Following 1, 3, 5, or 7 d of stimulation, VEGF induced a significant increase in HDFC proliferation compared with the corresponding control, while VEGF was effective at increasing ALP activity at the incubation time point of 3, 5, or 7 d. PD98059 and U0126 could attenuate the VEGF-mediated HDFC proliferation. Fewer apoptotic cells were observed in the VEGF-treated groups compared to the controls, although the difference was not statistically significant.
  
  
  CONCLUSIONS
  VEGF is expressed in cultured HDFC, and at a proper concentration range can stimulate HDFC proliferation, induce HDFC to differentiate in a "cementoblast/osteoblast" pathway and protect HDFC from apoptosis. The MAPK signaling pathway might be involved in the VEGF-mediated HDFC proliferation.
authors.affiliation: Department of Orthodontics, Qindu Stomatological College, Fourth Military Medical University, Xi'an 710032, China.
authors.forename: Xue-peng
authors.initials: XP
authors.lastname: Chen
authors.forename: Hong
authors.initials: H
authors.lastname: Qian
authors.forename: Jun-jie
authors.initials: JJ
authors.lastname: Wu
authors.forename: Xian-wei
authors.initials: XW
authors.lastname: Ma
authors.forename: Ze-xu
authors.initials: ZX
authors.lastname: Gu
authors.forename: Hai-yan
authors.initials: HY
authors.lastname: Sun
authors.forename: Yin-zhong
authors.initials: YZ
authors.lastname: Duan
authors.forename: Zuo-lin
authors.initials: ZL
authors.lastname: Jin
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D017209:Apoptosis / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation; D002478:Cells, Cultured; D003795:Dental Sac / Q000166:cytology / Q000378:metabolism; D006801:Humans; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism*
chemical_list: D042461:Vascular Endothelial Growth Factor A; D000469:Alkaline Phosphatase