Breast Cancer and Its Relationship With the Microbiota

Breast cancer ranks first in women, and is the second cause of death in this gender. In addition to genetics, the environment contributes to the development of the disease, although the factors involved are not well known. Among the latter is the influence of microorganisms and, therefore, attention is recently being paid to the mammary microbiota. The hypothesis of this study is that the risk of breast cancer could be associated with the composition and functionality of the mammary/gut microbiota, and that exposure to environmental contaminants (endocrine disruptors, EDCs) might contribute to alter the microbiota. This is a case-control clinical study that will be performed in women between 25 and 70 years of age. Cases will be women diagnosed and surgically intervened of breast cancer (stages I and II). Women with antecedents of cancer or advanced tumor stage (metastasis), or who have received antibiotic treatment within 3 months prior to recruitment, or any neoadjuvant therapy, will be excluded. Controls will be women surgically intervened of breast augmentation or reduction. Women with oncological, gynecological or endocrine history, and those who have received antibiotic treatment within 3 months prior to recruitment will also be excluded. Blood, urine, breast tissue and stool samples will be collected. Data regarding anthropometric, sociodemographic, reproductive history, tumor features and dietary habits will be gathered. Metabolomic studies will be carried out in stool and breast tissue samples. Metagenomic studies will also be performed in stool and breast tissue samples to ascertain the viral, fungal, bacterial and archaea populations of the microbiota. Quantitation of estrogens, estrogen metabolites and EDCs in samples of serum, urine and breast tissue will also be performed. This is the first time that the contribution of bacteria, archaea, viruses and fungi together with their alteration by environmental contaminants to the risk of breast cancer will be evaluated in the same study. Results obtained could contribute to elucidate risk factors, improve the prognosis, as well as to propose novel intervention studies in this disease.

Sex

Female

Minimum age

25 Years

Maximum age

70 Years

Inclusion criteria:

* Cases will be women diagnosed and surgically intervened of breast cancer, stages I and II.
* Controls will be women surgically intervened of breast augmentation or reduction.

Exclusion criteria:

1. For cases:

   * Women with antecedents of cancer or advanced tumor stage (metastasis).
   * Women who have received antibiotic treatment 3 months prior to recruitment, or any neoadjuvant therapy.
2. For controls:

   * Women with oncological, gynecological or endocrine antecedents.
   * Women who have received antibiotic treatment 3 months prior to recruitment.

• RESULTRuiz-Marin CM, Isabel Alvarez-Mercado A, Plaza-Diaz J, Rodriguez-Lara A, Gallart-Aragon T, Sanchez-Barron MT, Lartategui SR, Alcaide-Lucena M, Fernandez MF, Fontana L. A Clustering Study of Sociodemographic Data, Dietary Patterns, and Gut Microbiota in Healthy and Breast Cancer Women Participating in the MICROMA Study. Mol Nutr Food Res. 2024 Aug;68(15):e2400253. doi: 10.1002/mnfr.202400253. Epub 2024 Jul 1. PMID 38950423
• DERIVEDPlaza-Diaz J, Alvarez-Mercado AI, Ruiz-Marin CM, Reina-Perez I, Perez-Alonso AJ, Sanchez-Andujar MB, Torne P, Gallart-Aragon T, Sanchez-Barron MT, Reyes Lartategui S, Garcia F, Chueca N, Moreno-Delgado A, Torres-Martinez K, Saez-Lara MJ, Robles-Sanchez C, Fernandez MF, Fontana L. Association of breast and gut microbiota dysbiosis and the risk of breast cancer: a case-control clinical study. BMC Cancer. 2019 May 24;19(1):495. doi: 10.1186/s12885-019-5660-y. PMID 31126257