RT Journal Article T1 Association of breast and gut microbiota dysbiosis and the risk of breast cancer: a case-control clinical study A1 Plaza-Díaz, Julio A1 Álvarez-Mercado, Ana I. A1 Ruiz-Marín, Carmen M. A1 Reina-Pérez, Iris A1 Pérez-Alonso, Alejandro J. A1 Sánchez-Andujar, María Belén A1 Torné, Pablo A1 Gallart-Aragón, Tania A1 Sánchez-Barrón, María Teresa A1 Reyes Lartategui, Saturnino A1 García, Federico A1 Chueca, Natalia A1 Moreno-Delgado, Ana A1 Torres-Martínez, Katia A1 Sáez-Lara, María José A1 Robles-Sánchez, Cándido A1 Fernández, Mariana F. A1 Fontana, Luis K1 Archaea K1 Bacteria K1 Breast cancer K1 Breast microbiota K1 Endocrine disruptors K1 Environmental pollutants K1 Fungi K1 Gut microbiota K1 Virus K1 Breast neoplasms K1 Neoplasias de la mama K1 Gastrointestinal microbiome K1 Microbioma sastrointestinal K1 Disruptores endocrinos K1 Contaminantes ambientales K1 Hongos AB Background: 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. We hypothesize 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 these microbiota.Methods: We describe 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 a period of 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 a period of 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.Discussion: 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. YR 2019 FD 2019-05-24 LK http://hdl.handle.net/10668/3162 UL http://hdl.handle.net/10668/3162 LA en NO Plaza-Díaz J, Álvarez-Mercado AI, Ruiz-Marín CM, Reina-Pérez I, Pérez-Alonso AJ, Sánchez-Andujar MB, et al. 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. DS RISalud RD Apr 17, 2025