Effectiveness of DIM Supplements to Increase 2-OHE1/16 Ratio in Premenopausal Mexican Women With Risk of Breast Cancer

Breast cancer is a public health problem in Mexico and its incidence rises when the woman is still premenopausal. Estrogen metabolism has been linked to breast cancer. Several studies reported that high concentrations of 2 hydroxyestrone (2OHE1) in urine have a protective effect for this neoplasia, whereas high concentrations of 16 alpha-hydroxyestrone (16αOHE1) in urine have the opposite effect, further has been reported that women with a ratio of estrogen metabolites 2OHE1:16αOHE1 in urine (REMU) less than 0.9, have ten times the risk of developing Breast Cancer than those women with an RMEU equal or more than 0.9. Other studies have showed that the active compounds of cruciferous vegetables, indole-3-carbinol (I3C) and its dimer, 3'3'diindolylmethane (DIM) induce benign pathway of metabolism of estrogens producing 2OHE1. Several studies, evaluate the pharmacokinetics and effect of I3C supplementation, finding that 300 to 600 mg of this compound are well tolerated and able to promote formation of 2OHE1 in women when supplemented for one month. In the case of DIM, only a pilot study has explored its effect in postmenopausal women with personal history of breast cancer in early stages, reporting an increase in the concentrations of 2OHE1. The purpose of this study was to evaluate the effectiveness of supplementation with DIM to increase urinary RMEU in premenopausal women at risk of Breast Cancer (RMEU less than 0.9). A clinical, randomized, double-blind study was performed with women attending on the urogynecology service of Institute National of Perinatology. Subjects were premenopausal women over 34 years who were healthy. The inclusion criteria's was had a RMEU less than 0.9 and were excluded for any medical condition, medication, or dietary or lifestyle habit that might interfere with estrogen metabolism. Patients were randomly assigned to one of two groups: one received orally at a daily dose of 75 mg of DIM for a period of 30 days and other group received orally at a daily placebo for a period of 30 days. All urine samples were collected from the women before DIM or placebo ingestion, after 30 days of DIM or placebo ingestion and finally after another 30 days once suspended supplementation. Analysis of the 2OHE1 and 16αOHE1 were determined using a commercially kit ESTRAMET™. The change in metabolites median concentrations and RMEU was assessed through the Wilcoxon test and these differences between groups through U Mann-Whitney test.