title: Expression of ERalpha and ERbeta in prostate cancer.
abstract: BACKGROUND
  It has been suggested that estrogens and their receptors (ERs) may be involved in the development and progression of prostate cancer. To elucidate the significance of these receptors, expression of both ERalpha and ERbeta was measured in benign and malignant prostate tumors, as well as in cell lines.
  
  
  METHODS
  Expression of ERalpha and ERbeta was measured in prostate hyperplasia (BPH, n = 7), androgen-dependent (n = 30) as well as hormone-refractory (n = 12) prostate carcinomas, and in four prostate cancer cell lines (LNCaP, DU145, PC-3, and 22Rv1) using real-time quantitative RT-PCR.
  
  
  RESULTS
  Only low-level expression of ERalpha was found in all tumor types and cell lines. The level of expression was similar to that observed in breast carcinomas found to be negative for ERalpha by immunohistochemistry. All cell lines showed low, but detectable, levels of ERbeta expression. The mean expression of ERbeta in the hormone-refractory carcinomas was about half that seen in BPH or the androgen-dependent carcinomas; however, the difference was not statistically significant.
  
  
  CONCLUSIONS
  The data suggest it is unlikely that alterations in the expression of either ER are commonly involved in the progression of prostate cancer.
authors.affiliation: Laboratory of Cancer Genetics, Institute of Medical Technology, University of Tampere, Tampere, Finland.
authors.forename: Marika J
authors.initials: MJ
authors.lastname: Linja
authors.forename: Kimmo J
authors.initials: KJ
authors.lastname: Savinainen
authors.forename: Teuvo L J
authors.initials: TL
authors.lastname: Tammela
authors.forename: Jorma J
authors.initials: JJ
authors.lastname: Isola
authors.forename: Tapio
authors.initials: T
authors.lastname: Visakorpi
mesh_terms: D001943:Breast Neoplasms / Q000235:genetics / Q000473:pathology; D002277:Carcinoma / Q000235:genetics / Q000378:metabolism*; D004273:DNA, Neoplasm / Q000235:genetics / Q000378:metabolism; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D011470:Prostatic Hyperplasia / Q000235:genetics / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D011960:Receptors, Estrogen / Q000096:biosynthesis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
chemical_list: D004273:DNA, Neoplasm; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D012333:RNA, Messenger; D011960:Receptors, Estrogen