title: The effect of oral 3,3'-diindolylmethane supplementation on the 2:16α-OHE ratio in BRCA1 mutation carriers.
abstract: Hormonal exposures are known to influence breast cancer risk among women with a BRCA1 mutation. Thus, dietary factors that increase the 2-hydroxyestrone (OHE):16α-OHE ratio, a biomarker inversely related to breast cancer development, may also influence cancer risk. We conducted a dietary intervention study to evaluate the ability of 300 mg/day of 3,3'-diindolylmethane (DIM) to increase the urinary 2:16α-OHE ratio in 20 women with a BRCA1 mutation. BRCA1 mutation carriers (n = 15) were assigned to receive 300 mg/day of Rx Balance BioREsponse DIM for 4-6 weeks (intervention group) and five BRCA1 mutation carriers did not take DIM (control group). The urinary 2:16α-OHE ratio was assessed at baseline and after 4-6 weeks by immunoassay. There was no significant effect of DIM on the 2:16α-OHE ratio (2.4 at baseline vs. 3.0 after the intervention, P = 0.35). A short dietary intervention with DIM did not significantly increase the 2:16α-OHE ratio in female BRCA1 mutation carriers. Larger studies investigating the effect of dietary or lifestyle interventions on circulating hormone levels in these high-risk women are warranted.
authors.affiliation: Women's College Research Institute, 790 Bay St, Toronto, ON, M5G 1N8, Canada, dina.nikitina@wchospital.ca.
authors.forename: Dina
authors.initials: D
authors.lastname: Nikitina
authors.forename: Marcia
authors.initials: M
authors.lastname: Llacuachaqui
authors.forename: Daniel
authors.initials: D
authors.lastname: Sepkovic
authors.forename: H Leon
authors.initials: HL
authors.lastname: Bradlow
authors.forename: Steven A
authors.initials: SA
authors.lastname: Narod
authors.forename: Joanne
authors.initials: J
authors.lastname: Kotsopoulos
mesh_terms: D000284:Administration, Oral; D000328:Adult; D005260:Female; D019398:Genes, BRCA1; D006579:Heterozygote; D006801:Humans; D006894:Hydroxyestrones / Q000652:urine*; D007211:Indoles / Q000008:administration & dosage*; D008875:Middle Aged; D009154:Mutation
chemical_list: D006894:Hydroxyestrones; D007211:Indoles; C026702:16-hydroxyestrone; C016392:3,3'-diindolylmethane; C024980:2-hydroxyestrone