title: ER-α36, a novel variant of estrogen receptor α, is involved in EGFR-related carcinogenesis in endometrial cancer.
abstract: OBJECTIVE
  To explore the role of estrogen receptor-α36 (ER-α36) in epidermal growth factor receptor (EGFR)-related carcinogenesis in endometrial cancer.
  
  
  METHODS
  The expression of ER-α36, EGFR, and phospho-extracellular signal-regulated kinase was analyzed using immunohistochemistry in endometrial cancer samples. The cellular localization of ER-α36 and EGFR was determined using immunofluorescence in the endometrial cancer Hec1A cells. The level of phospho-extracellular signal-regulated kinase of Hec1A cells was determined using Western blotting after treatment with epidermal growth factor.
  
  
  RESULTS
  Positive rate of ER-α36 was increased in high-stage (P = .03) and high-grade (P = .224) endometrial cancer; expression of ER-α36 and EGFR exhibited a significant positive correlation (r = 0.334, P = .025) and they showed substantial colocalization on the plasma membrane of glandular cells; phospho-extracellular signal-regulated kinase positive rate in ER-α36 positive group and EGFR positive group was higher than that of ER-α36 negative group (P = .014) and EGFR negative group (P = .016); finally, ER-α36 mediated epidermal growth factor-stimulated extracellular signal-regulated kinase activation in Hec1A cells.
  
  
  CONCLUSIONS
  ER-α36 mediates EGFR-related extracellular signal-regulated kinase activation in endometrial cancer.
authors.affiliation: Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China.
authors.forename: Bin-Bin
authors.initials: BB
authors.lastname: Tu
authors.forename: Sheng-Li
authors.initials: SL
authors.lastname: Lin
authors.forename: Li-Ying
authors.initials: LY
authors.lastname: Yan
authors.forename: Zhao-Yi
authors.initials: ZY
authors.lastname: Wang
authors.forename: Qing-Yuan
authors.initials: QY
authors.lastname: Sun
authors.forename: Jie
authors.initials: J
authors.lastname: Qiao
mesh_terms: D045744:Cell Line, Tumor; D016889:Endometrial Neoplasms / Q000378:metabolism* / Q000473:pathology; D004815:Epidermal Growth Factor / Q000494:pharmacology; D066246:ErbB Receptors / Q000378:metabolism*; D047628:Estrogen Receptor alpha / Q000378:metabolism*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005260:Female; D006801:Humans; D010766:Phosphorylation / Q000187:drug effects; D020033:Protein Isoforms / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D047628:Estrogen Receptor alpha; D020033:Protein Isoforms; D004815:Epidermal Growth Factor; D066246:ErbB Receptors; D048049:Extracellular Signal-Regulated MAP Kinases