title: Flaxseed supplementation (not dietary fat restriction) reduces prostate cancer proliferation rates in men presurgery.
abstract: BACKGROUND
  Prostate cancer affects one of six men during their lifetime. Dietary factors are postulated to influence the development and progression of prostate cancer. Low-fat diets and flaxseed supplementation may offer potentially protective strategies.
  
  
  METHODS
  We undertook a multisite, randomized controlled trial to test the effects of low-fat and/or flaxseed-supplemented diets on the biology of the prostate and other biomarkers. Prostate cancer patients (n = 161) scheduled at least 21 days before prostatectomy were randomly assigned to one of the following arms: (a) control (usual diet), (b) flaxseed-supplemented diet (30 g/d), (c) low-fat diet (<20% total energy), or (d) flaxseed-supplemented, low-fat diet. Blood was drawn at baseline and before surgery and analyzed for prostate-specific antigen, sex hormone-binding globulin, testosterone, insulin-like growth factor-I and binding protein-3, C-reactive protein, and total and low-density lipoprotein cholesterol. Tumors were assessed for proliferation (Ki-67, the primary endpoint) and apoptosis.
  
  
  RESULTS
  Men were on protocol an average of 30 days. Proliferation rates were significantly lower (P < 0.002) among men assigned to the flaxseed arms. Median Ki-67-positive cells/total nuclei ratios (x100) were 1.66 (flaxseed-supplemented diet) and 1.50 (flaxseed-supplemented, low-fat diet) versus 3.23 (control) and 2.56 (low-fat diet). No differences were observed between arms with regard to side effects, apoptosis, and most serologic endpoints; however, men on low-fat diets experienced significant decreases in serum cholesterol (P = 0.048).
  
  
  CONCLUSIONS
  Findings suggest that flaxseed is safe and associated with biological alterations that may be protective for prostate cancer. Data also further support low-fat diets to manage serum cholesterol.
authors.affiliation: Division of Cancer Prevention and Population Sciences, The University of Texas M. D. Anderson Cancer Center, P.O. Box 301439, Unit 1330, Houston, TX 77230-1439, USA. wdemarkw@mdanderson.org
authors.forename: Wendy
authors.initials: W
authors.lastname: Demark-Wahnefried
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Polascik
authors.forename: Stephen L
authors.initials: SL
authors.lastname: George
authors.forename: Boyd R
authors.initials: BR
authors.lastname: Switzer
authors.forename: John F
authors.initials: JF
authors.lastname: Madden
authors.forename: Mack T
authors.initials: MT
authors.lastname: Ruffin
authors.forename: Denise C
authors.initials: DC
authors.lastname: Snyder
authors.forename: Kouros
authors.initials: K
authors.lastname: Owzar
authors.forename: Vera
authors.initials: V
authors.lastname: Hars
authors.forename: David M
authors.initials: DM
authors.lastname: Albala
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Walther
authors.forename: Cary N
authors.initials: CN
authors.lastname: Robertson
authors.forename: Judd W
authors.initials: JW
authors.lastname: Moul
authors.forename: Barbara K
authors.initials: BK
authors.lastname: Dunn
authors.forename: Dean
authors.initials: D
authors.lastname: Brenner
authors.forename: Lori
authors.initials: L
authors.lastname: Minasian
authors.forename: Philip
authors.initials: P
authors.lastname: Stella
authors.forename: Robin T
authors.initials: RT
authors.lastname: Vollmer
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood; D018752:Diet, Fat-Restricted; D019587:Dietary Supplements; D019597:Flax; D006801:Humans; D008297:Male; D008875:Middle Aged; D016012:Poisson Distribution; D011300:Preoperative Care; D011471:Prostatic Neoplasms / Q000178:diet therapy* / Q000473:pathology / Q000601:surgery; D018709:Statistics, Nonparametric
chemical_list: D014408:Biomarkers, Tumor