title: Short-term soy isoflavone intervention in patients with localized prostate cancer: a randomized, double-blind, placebo-controlled trial.
abstract: OBJECTIVE
  We describe the effects of soy isoflavone consumption on prostate specific antigen (PSA), hormone levels, total cholesterol, and apoptosis in men with localized prostate cancer.
  
  
  RESULTS
  We conducted a double-blinded, randomized, placebo-controlled trial to examine the effect of soy isoflavone capsules (80 mg/d of total isoflavones, 51 mg/d aglucon units) on serum and tissue biomarkers in patients with localized prostate cancer. Eighty-six men were randomized to treatment with isoflavones (n=42) or placebo (n=44) for up to six weeks prior to scheduled prostatectomy. We performed microarray analysis using a targeted cell cycle regulation and apoptosis gene chip (GEArrayTM). Changes in serum total testosterone, free testosterone, total estrogen, estradiol, PSA, and total cholesterol were analyzed at baseline, mid-point, and at the time of radical prostatectomy. In this preliminary analysis, 12 genes involved in cell cycle control and 9 genes involved in apoptosis were down-regulated in the treatment tumor tissues versus the placebo control. Changes in serum total testosterone, free testosterone, total estrogen, estradiol, PSA, and total cholesterol in the isoflavone-treated group compared to men receiving placebo were not statistically significant.
  
  
  CONCLUSIONS
  These data suggest that short-term intake of soy isoflavones did not affect serum hormone levels, total cholesterol, or PSA.
  
  
  BACKGROUND
  ClinicalTrials.gov NCT00255125.
authors.affiliation: Department of Dietetics and Nutrition, University of Kansas Medical Center, Kansas City, Kansas, USA. jhamilton-reeves@kumc.edu
authors.forename: Jill M
authors.initials: JM
authors.lastname: Hamilton-Reeves
authors.forename: Snigdha
authors.initials: S
authors.lastname: Banerjee
authors.forename: Sushanta K
authors.initials: SK
authors.lastname: Banerjee
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Holzbeierlein
authors.forename: J Brantley
authors.initials: JB
authors.lastname: Thrasher
authors.forename: Suman
authors.initials: S
authors.lastname: Kambhampati
authors.forename: John
authors.initials: J
authors.lastname: Keighley
authors.forename: Peter
authors.initials: P
authors.lastname: Van Veldhuizen
mesh_terms: D017209:Apoptosis / Q000235:genetics; D014408:Biomarkers, Tumor / Q000235:genetics; D002453:Cell Cycle / Q000235:genetics; D002784:Cholesterol / Q000097:blood; D004311:Double-Blind Method; D004967:Estrogens / Q000097:blood; D006801:Humans; D007529:Isoflavones / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D008517:Phytotherapy; D010919:Placebos; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology*; D013025:Glycine max / Q000737:chemistry*; D013739:Testosterone / Q000097:blood; D013997:Time Factors
chemical_list: D014408:Biomarkers, Tumor; D004967:Estrogens; D007529:Isoflavones; D010919:Placebos; D013739:Testosterone; D002784:Cholesterol; D017430:Prostate-Specific Antigen