title: Serum and urine tissue kallikrein concentrations in male-to-female transsexuals treated with antiandrogens and estrogens.
abstract: BACKGROUND
  The expression of human tissue kallikrein genes is regulated by steroid hormones, but most studies have been conducted with cancer cell lines. Our purpose was to examine serum and urinary tissue kallikrein concentration changes in male-to-female transsexuals before and after treatment with antiandrogens and estrogens.
  
  
  METHODS
  Thirty-five male-to-female transsexuals receiving cyproterone acetate and estrogens (orally or transdermally) were included in this study. Serum and urine samples were collected before initiation of therapy and 4 and 12 months post therapy. ELISAs were used to measure multiple kallikreins in serum and urine.
  
  
  RESULTS
  After antiandrogen and estrogen therapy, serum testosterone concentrations decreased dramatically, as did serum and urinary concentrations of human glandular kallikrein (hK2) and prostate-specific antigen (PSA; hK3). Statistically significant but relatively small changes in serum and urinary concentrations of many other kallikreins were also seen. Kallikreins in serum and urine were correlated before and after treatment.
  
  
  CONCLUSIONS
  The concentrations of hK2 and hK3, but not of any other kallikreins, decrease dramatically after combined antiandrogen and estrogen treatment in male-to-female transsexuals. The smaller responses of the other kallikreins presumably reflect their expression in multiple tissues.
authors.affiliation: Department of Endocrinology, VU University Medical Centre, Amsterdam, The Netherlands.
authors.forename: Margrita H
authors.initials: MH
authors.lastname: Slagter
authors.forename: Louis J G
authors.initials: LJ
authors.lastname: Gooren
authors.forename: Willem
authors.initials: W
authors.lastname: de Ronde
authors.forename: Antoninus
authors.initials: A
authors.lastname: Soosaipillai
authors.forename: Andreas
authors.initials: A
authors.lastname: Scorilas
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Giltay
authors.forename: Miltiadis
authors.initials: M
authors.lastname: Paliouras
authors.forename: Eleftherios P
authors.initials: EP
authors.lastname: Diamandis
mesh_terms: D000328:Adult; D000726:Androgen Antagonists / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000097:blood / Q000652:urine; D017373:Cyproterone Acetate / Q000627:therapeutic use; D004967:Estrogens / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020840:Tissue Kallikreins / Q000097:blood* / Q000652:urine*; D014189:Transsexualism / Q000097:blood* / Q000652:urine*
chemical_list: D000726:Androgen Antagonists; D014408:Biomarkers, Tumor; D004967:Estrogens; D017373:Cyproterone Acetate; D020840:Tissue Kallikreins