title: [ERK signaling pathway mediated epithelial-mesenchymal transition induced by SiO₂ in human bronchial epithelial cells].
abstract: OBJECTIVE
  To determine the role of extracellular signal regulated kinase (ERK) signaling pathway in SiO₂ induced epithelial-mesenchymal transition (EMT) in human bronchial epithelial cells (HBEC) in vitro.
  
  
  METHODS
  HBEC were treated with SiO₂ (0-300 μg/mL) for 72 h or pretreated with U0126 (0-30 μmol/L) for 1 h and then treated with 200 μg/mL SiO₂ for 72 h. Western blot was used to detect the protein expression of E-cadherin and α-smooth muscle actin (α-SMA). The activity of ERK was examined by mitogen-activated protein kinase (MAPK) activity assay kit in HBEC exposing to SiO₂ (200 μg/mL) for 0-8 h.
  
  
  RESULTS
  The expression of E-cadherin decreased gradually in SiO₂ -stimulated HBEC, and the effect was most significant at 300 μg/mL (P<0.01). The expression of α-SMA increased and the effect was most evident at 200 μg/mL (P<0.01). With SiO₂ treatment, the activity of ERK was upregulated significantly. The phosphorylation of ERK increased at 30 min and decreased after 1 h. U0126 significantly inhibited SiO₂ -induced expression changes in E-cadherin and α-SMA. At 30 μmol/L, the effect was most evident(P<0.01).
  
  
  CONCLUSIONS
  ERK signaling pathway mediated EMT induced by SiO₂ in HBEC.
authors.affiliation: Department of Pathology, Xiangya School of Medicine, Central South University, Changsha 410013, China.
authors.forename: Zhenqin
authors.initials: Z
authors.lastname: Gao
authors.forename: Yongbin
authors.initials: Y
authors.lastname: Hu
authors.forename: Jingwu
authors.initials: J
authors.lastname: Peng
authors.forename: Zhenghao
authors.initials: Z
authors.lastname: Deng
authors.forename: Guannan
authors.initials: G
authors.lastname: Liang
authors.forename: Haiying
authors.initials: H
authors.lastname: Jiang
authors.forename: Jianhua
authors.initials: J
authors.lastname: Zhou
mesh_terms: D000199:Actins / Q000378:metabolism; D001980:Bronchi / Q000166:cytology; D015820:Cadherins / Q000378:metabolism; D054338:Cell Transdifferentiation / Q000187:drug effects*; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000166:cytology* / Q000502:physiology; D058750:Epithelial-Mesenchymal Transition; D006801:Humans; D020935:MAP Kinase Signaling System / Q000502:physiology*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D012822:Silicon Dioxide / Q000494:pharmacology*
chemical_list: D000199:Actins; D015820:Cadherins; D012822:Silicon Dioxide; D020928:Mitogen-Activated Protein Kinases