title: [Epidermal growth factor stimulates the proliferation of human esophageal squamous cell carcinoma HKESC-1 cells by increasing COX-2 expression].
abstract: OBJECTIVE
  To investigate the mechanisms responsible for epidermal growth factor (EGF)-induced proliferation of human esophageal squamous cell carcinoma cells.
  
  
  METHODS
  (3)H-thymidine incorporation assay was used to assess the proliferation of HKESC-1 cells exposed to EGF stimulation. Enzyme immunoassay was used to measure PGE(2) release from HKESC-1 cells, and the protein levels of cyclooxygenase 1 (COX-1), COX-2, EP1 and EP2 in EGF-stimulated cells were determined by Western blotting.
  
  
  RESULTS
  EGF upregulated COX-2 protein expression but produced no obvious effect on COX-1 protein expression in HKESC-1 cells. As a consequence of increased COX-2, EGF further enhanced cellular PGE(2) release. EGF stimulation also resulted in increased protein expression of EP2, a subtype of PGE(2) receptors. Both the non-selective COX inhibitor indomethacin and the selective COX-2 inhibitor SC-236 completely abolished EGF-induced PGE(2) release, and suppressed the mitogenic effect of EGF.
  
  
  CONCLUSIONS
  EGF stimulates the proliferation of HKESC-1 cells by increasing COX-2 protein expression and PGE(2) release. Upregulated EP2 protein expression may further amplify the mitogenic action of PGE(2).
authors.affiliation: School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, China. yule0423@gmail.com
authors.forename: Le
authors.initials: L
authors.lastname: Yu
authors.forename: Chi-hin
authors.initials: CH
authors.lastname: Cho
authors.forename: Shu-wen
authors.initials: SW
authors.lastname: Liu
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D015232:Dinoprostone / Q000378:metabolism; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D004938:Esophageal Neoplasms / Q000473:pathology*; D006801:Humans; D011720:Pyrazoles / Q000494:pharmacology; D058307:Receptors, Prostaglandin E, EP2 Subtype / Q000378:metabolism; D013449:Sulfonamides / Q000494:pharmacology; D015854:Up-Regulation / Q000187:drug effects; D000096926:Benzenesulfonamides
chemical_list: D051546:Cyclooxygenase 2; D015232:Dinoprostone; D004815:Epidermal Growth Factor; D011720:Pyrazoles; D058307:Receptors, Prostaglandin E, EP2 Subtype; D013449:Sulfonamides; C119130:4-(5-(4-chlorophenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl)benzenesulfonamide; D000096926:Benzenesulfonamides; C545644:PTGER2 protein, human; C496540:PTGS2 protein, human