Soy products in the management of breast cancer

Curr Opin Clin Nutr Metab Care. 2012 Nov;15(6):586-91. doi: 10.1097/MCO.0b013e328359156f.

Abstract

Purpose of review: Meta-analyses of epidemiological studies of soy consumption and breast cancer risk have demonstrated modest protective effects, usually attributed to isoflavones. Concern has been expressed, however, that the estrogenic activity of isoflavones may have adverse effects on breast cancer recurrence.

Recent findings: The review covers epidemiological studies that have investigated the impact of soy consumption in breast cancer patients on recurrence and mortality. There are preliminary data to suggest that soy has differential effects on recurrence in human epidermal growth factor receptor-2 positive and human epidermal growth factor receptor-2 negative tumours. Recent studies on mechanisms of action of soy in breast cancer provide insights into epigenetic effects and the interaction of isoflavones with IGF-1 and with a number of polymorphisms of genes associated with breast cancer risk such as MDM2 and CYP1B1.

Summary: Overall, these studies indicate that soy foods consumed at levels comparable to those in Asian populations have no detrimental effects on risk of breast cancer recurrence and in some cases significantly reduce the risk. Importantly, soy does not appear to interfere with tamoxifen or anastrozole therapy. Recent research suggests that women who are at increased risk of breast cancer due to polymorphisms in genes associated with the disease may especially benefit from high soy isoflavone intake.

Publication types

  • Review

MeSH terms

  • Anastrozole
  • Animals
  • Aryl Hydrocarbon Hydroxylases / genetics
  • Aryl Hydrocarbon Hydroxylases / metabolism
  • Asian Continental Ancestry Group
  • Breast Neoplasms / diagnosis
  • Breast Neoplasms / epidemiology*
  • Breast Neoplasms / genetics
  • Breast Neoplasms / prevention & control*
  • Cytochrome P-450 CYP1B1
  • Diet* / adverse effects
  • Drug Interactions
  • Female
  • Humans
  • Incidence
  • Isoflavones / adverse effects
  • Isoflavones / pharmacology*
  • Meta-Analysis as Topic
  • Nitriles / pharmacology
  • Polymorphism, Genetic
  • Prognosis
  • Proto-Oncogene Proteins c-mdm2 / genetics
  • Proto-Oncogene Proteins c-mdm2 / metabolism
  • Receptor, ErbB-2 / genetics
  • Receptor, ErbB-2 / metabolism
  • Recurrence
  • Risk Factors
  • Soy Foods* / adverse effects
  • Tamoxifen / pharmacology
  • Triazoles / pharmacology

Substances

  • Isoflavones
  • Nitriles
  • Triazoles
  • Tamoxifen
  • Anastrozole
  • Aryl Hydrocarbon Hydroxylases
  • CYP1B1 protein, human
  • Cytochrome P-450 CYP1B1
  • MDM2 protein, human
  • Proto-Oncogene Proteins c-mdm2
  • ERBB2 protein, human
  • Receptor, ErbB-2