title: Dramatic suppression of plasma and urinary prostate specific antigen and human glandular kallikrein by antiandrogens in male-to-female transsexuals.
abstract: OBJECTIVE
  Prostate specific antigen (PSA) and human glandular kallikrein (hK2) are mainly produced by the prostate and their genes are regulated by androgens through the androgen receptor. We determine whether PSA and hK2 change significantly in plasma and urine after antiandrogen treatment in male-to-female transsexuals.
  
  
  METHODS
  Plasma and urine PSA and hK2 were measured with highly sensitive immunofluorometric procedures capable of detecting within 1 or 6 ng./l. PSA or hK2, respectively. Study groups consisted of 10 men treated with cyproterone acetate only (group 1), 15 transdermal estradiol plus cyproterone acetate (group 2) and 31 ethinyl estradiol plus cyproterone acetate (group 3). Plasma and urine samples were collected before initiation of treatment as well as after 4 months of hormonal therapy. For a subset of group 3 patients blood and urine samples were also obtained after 12 months of treatment.
  
  
  RESULTS
  Cyproterone acetate, a steroidal antiandrogen, alone or with estradiol was able to suppress greater than 90% of plasma and urinary PSA and hK2 concentration after 4 or 12 months of therapy.
  
  
  CONCLUSIONS
  Cyproterone acetate therapy causes dramatic suppression of plasma and urinary PSA and hK2 in men without prostate cancer. Since cyproterone acetate is used for prostate cancer treatment, suppression of PSA after hormonal therapy may not accurately reflect therapy success in reducing tumor burden.
authors.affiliation: Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, University of Toronto, Ontario, Canada.
authors.forename: C V
authors.initials: CV
authors.lastname: Obiezu
authors.forename: E J
authors.initials: EJ
authors.lastname: Giltay
authors.forename: A
authors.initials: A
authors.lastname: Magklara
authors.forename: A
authors.initials: A
authors.lastname: Scorilas
authors.forename: L
authors.initials: L
authors.lastname: Gooren
authors.forename: H
authors.initials: H
authors.lastname: Yu
authors.forename: E P
authors.initials: EP
authors.lastname: Diamandis
mesh_terms: D000293:Adolescent; D000328:Adult; D000726:Androgen Antagonists / Q000494:pharmacology*; D017373:Cyproterone Acetate / Q000494:pharmacology*; D004958:Estradiol / Q000494:pharmacology*; D045166:Estradiol Congeners / Q000494:pharmacology*; D004997:Ethinyl Estradiol / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood* / Q000652:urine*; D013997:Time Factors; D020840:Tissue Kallikreins / Q000097:blood* / Q000652:urine*; D014189:Transsexualism / Q000097:blood* / Q000652:urine*
chemical_list: D000726:Androgen Antagonists; D045166:Estradiol Congeners; D004997:Ethinyl Estradiol; D017373:Cyproterone Acetate; D004958:Estradiol; D020840:Tissue Kallikreins; D017430:Prostate-Specific Antigen