title: Serum androgens and prostate cancer risk: results from the placebo arm of the Prostate Cancer Prevention Trial.
abstract: BACKGROUND
  Compelling and long-standing data suggest that androgens play an important role in the development of both normal prostate epithelium and prostate cancer. Although testosterone administration can induce prostate cancer (PCA) in laboratory animals, serum-based epidemiologic studies examining androgens in humans have not consistently supported a role for androgens in prostate carcinogenesis. We examined whether pre-diagnostic serum androgens were associated with PCA risk in the placebo arm of the Prostate Cancer Prevention Trial.
  
  
  METHODS
  In this nested case-control study, cases (n = 1,032) were primarily local-stage, biopsy-detected cancers, and controls (n = 1,025) were biopsy-confirmed to be PCA-free. Pre-diagnostic serum androgens (total testosterone, 3α-androstanediol glucuronide, free testosterone), estrogen-to-testosterone ratio, and sex hormone-binding globulin (SHBG) concentrations were measured in pooled (baseline and year 3) blood samples.
  
  
  RESULTS
  We found no significant associations between serum androgens, estrogen-to-testosterone ratios, or SHBG and risk of total, low (Gleason <7) or high-grade (Gleason 7-10) PCA.
  
  
  CONCLUSIONS
  Much remains to be learned about the role of androgens in prostate carcinogenesis. Further research is needed to evaluate the role of androgens, timing of exposure, genetic modulators of androgen metabolism, or environmental exposures that may affect androgen influence on prostate carcinogenesis.
authors.affiliation: Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, WA, USA. jschenk@fredhutch.org.
authors.forename: Jeannette M
authors.initials: JM
authors.lastname: Schenk
authors.affiliation: Cancer Prevention Program, SWOG, Fred Hutchinson Cancer Research Center, Seattle, WA, USA. ctill@fredhutch.org.
authors.forename: Cathee
authors.initials: C
authors.lastname: Till
authors.affiliation: Cancer Prevention Institute of California, Fremont, CA, USA. Ann.Hsing@CPIC.org.
authors.forename: Ann W
authors.initials: AW
authors.lastname: Hsing
authors.affiliation: Department of Obstetrics/Gynecology, University of Southern California, Los Angeles, CA, USA. stanczyk@usc.edu.
authors.forename: Frank Z
authors.initials: FZ
authors.lastname: Stanczyk
authors.affiliation: Cancer Prevention and Control, Roswell Park Cancer Institute, Buffalo, NY, USA. Zhihong.Gong@RoswellPark.org.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Gong
authors.affiliation: Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, WA, USA. mneuhous@fredhutch.org.
authors.forename: Marian L
authors.initials: ML
authors.lastname: Neuhouser
authors.affiliation: Division of Tropical Health and Medicine, James Cook University, Townsville, QLD, Australia. jreichardt@yachaytech.edu.ec.|YachayTech University, San Miguel de Urcuquí, Eduador. jreichardt@yachaytech.edu.ec.
authors.forename: Juergen K
authors.initials: JK
authors.lastname: Reichardt
authors.affiliation: Clinical Cancer Prevention, The University of Texas MD Anderson Cancer Center, Houston, TX, USA. ahoque@mdanderson.org.
authors.forename: Ashraful M
authors.initials: AM
authors.lastname: Hoque
authors.affiliation: Genitourinary Malignancies Branch, National Cancer Institute, Bethesda, MD, USA. figgw@helix.nih.gov.
authors.forename: William D
authors.initials: WD
authors.lastname: Figg
authors.affiliation: Cancer Prevention Program, SWOG, Fred Hutchinson Cancer Research Center, Seattle, WA, USA. pgoodman@fredhutch.org.
authors.forename: Phyllis J
authors.initials: PJ
authors.lastname: Goodman
authors.affiliation: Cancer Prevention Program, SWOG, Fred Hutchinson Cancer Research Center, Seattle, WA, USA. ctangen@fredhutch.org.
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Tangen
authors.affiliation: Cancer Therapy and Research Center, University of Texas Health Sciences Center San Antonio, San Antonio, TX, USA. ThompsonI@uthscsa.edu.
authors.forename: Ian M
authors.initials: IM
authors.lastname: Thompson
mesh_terms: D000368:Aged; D000728:Androgens / Q000097:blood; D015113:Androstane-3,17-diol / Q000031:analogs & derivatives* / Q000097:blood; D001132:Arm; D001706:Biopsy; D016022:Case-Control Studies; D004958:Estradiol / Q000097:blood*; D004970:Estrone / Q000097:blood*; D006801:Humans; D007610:Kallikreins / Q000097:blood; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood* / Q000453:epidemiology; D012307:Risk Factors; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism*; D013739:Testosterone / Q000097:blood*
chemical_list: D000728:Androgens; D012738:Sex Hormone-Binding Globulin; D015113:Androstane-3,17-diol; C028895:androstane-3,17-diol glucuronide; D004970:Estrone; D013739:Testosterone; D004958:Estradiol; C549870:KLK3 protein, human; D007610:Kallikreins; D017430:Prostate-Specific Antigen
keywords: Androgens; Prostate Cancer Prevention Trial; Prostate cancer