title: Differential expression patterns of estrogen receptor (ER)-β splice variants between papillary thyroid cancer and nodular thyroid goiter.
abstract: BACKGROUND
  The aim of this study was to investigate the expression patterns of estrogen receptor (ER) β1 (wild-type ERβ) and ERβ2 (ERβcx) in papillary thyroid cancer (PTC) and nodular thyroid goiter (NTG), and to explore the reasons for the higher incidence of PTC in women of reproductive age.
  
  
  METHODS
  ERβ1 and ERβ2 expression was examined immunohistochemically on paraffin-embedded thyroid tissues from 106 patients with PTC and 30 patients with NTG.
  
  
  RESULTS
  There was significant difference in the subcellular localization of ERβ1 (P<0.001), but not in the positive percentage, between PTC and NTG specimens. No significant difference was found in the positive percentage or the subcellular distribution of ERβ2 expression between PTC and NTG specimens. Both nuclear and nucleocytoplasmic ERβ1 expressions were significantly lower in PTC lesions than in NTG tissue (P<0.001 and P<0.05, respectively), while ERβ2 expression was significantly higher in the former than the latter (P<0.05). ERβ1 expression in reproductive-aged (18~45 years) female patients with PTC was lower than that in age-matched male patients (P<0.05), while ERβ2 expression had the opposite expression profile (P<0.05). There was no significant difference in ERβ1 and ERβ2 expression between reproductive-aged and advanced reproductive-aged (>45 years) female patients with PTC.
  
  
  CONCLUSIONS
  This preliminary study indicates that the expression patterns of ERβ1 and ERβ2 differ between malignant PTC lesions and benign NTG tissue, and their expression might be involved in the female predominance of PTC during the reproductive years. The clinical and biological significance of these results await further investigation.
authors.affiliation: Department of General Surgery, The First Hospital of China Medical University, Shenyang, China.
authors.forename: Wenwu
authors.initials: W
authors.lastname: Dong
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Huang
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
authors.forename: Zhongyan
authors.initials: Z
authors.lastname: Shan
authors.forename: Weiping
authors.initials: W
authors.lastname: Teng
mesh_terms: D000328:Adult; D000367:Age Factors; D002277:Carcinoma / Q000453:epidemiology* / Q000378:metabolism*; D002291:Carcinoma, Papillary; D002467:Cell Nucleus / Q000378:metabolism; D002681:China / Q000453:epidemiology; D003593:Cytoplasm / Q000378:metabolism; D047629:Estrogen Receptor beta / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006044:Goiter, Nodular / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D015994:Incidence; D008297:Male; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism*; D012737:Sex Factors; D018709:Statistics, Nonparametric; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000453:epidemiology* / Q000378:metabolism*
chemical_list: D047629:Estrogen Receptor beta; D020033:Protein Isoforms