Metagenomics Analysis of Breast Microbiome Highlights the Abundance of Rothia Genus in Tumor Tissues

Abstract

Breast cancer is one of the main global priorities in terms of public health. It remains the most frequent cancer in women and is the leading cause of their death. The human microbiome plays various roles in maintaining health by ensuring a dynamic balance with the host or in the appearance of various pathologies including breast cancer. In this study, we performed an analysis of bacterial signature differences between tumor and adjacent tissues of breast cancer patients in Morocco. Using 16S rRNA gene sequencing, we observed that adjacent tissue contained a much higher percentage of the Gammaproteobacteria class (35.7%) while tumor tissue was characterized by a higher percentage of Bacilli and Actinobacteria classes, with about 18.8% and 17.2% average abundance, respectively. Analysis of tumor subtype revealed enrichment of genus Sphingomonodas in TNBC while Sphingomonodas was predominant in HER2. The LEfSe and the genus level heatmap analysis revealed a higher abundance of the Rothia genus in tumor tissues. The identified microbial communities can therefore serve as potential biomarkers for prognosis and diagnosis, while also helping to develop new strategies for the treatment of breast cancer patients.

Breast Cancer Exposomics

“…Zhang et al (2028), using liquid chromatography MS-based global metabolomics coupled with targeted metabolomics, demonstrated that the human microbiome can be significantly perturbed by exposure to xenobiotic mixtures, resulting in dysbiosis and metabolite-modified profiles that play an important role in the host’s health [ 66 ]. With regard to BC, it is well-known that human microbiome-related disturbance may contribute to BC development by producing toxins or promoting inflammation, while certain types of bacteria may have positive effects against BC [ 67 ]. Recently, network biology techniques were used to identify xenobiotics that target hub proteins in the human interactomes, mainly in disease-associated proteins and contaminant-sensitive biomarkers [ 68 ], suggesting a new omics field, environmental interactomics.…”

Omics-Based Investigations of Breast Cancer

“…Thus, a methylomics-based study used a methylatyed DNA immunoprecipitation microarray (MeDIP-chip) on DNA samples isolated from the white blood cells of young patients with BC, emphasizing the hypermethylation of several genes, such as APC , HDAC1 , GSK1 , SLC6A3 , Rab40C , ZNF584 , and FOXD3 [ 142 ]. Additionally, metagenomics analyses of normal and malignant breast microbiomes using 16S rRNA gene sequencing identified specific microbial communities that could serve as potential biomarkers for prognoses and diagnoses, with implications in developing novel strategies for the treatment of BC patients [ 145 ].…”

Targeted Gene Panel Sequencing Unveiled New Pathogenic Mutations in Patients With Breast Cancer

“…Breast cancer is believed to be a complicated disease that arises from a combination of environmental, microbiome, and genetics factors that increase its pathogenicity. 3 Indeed, at the genetics level, BC is associated with a number of genes with high- and moderate to low-penetrance susceptibility, implicated in DNA damage response. Breast cancer type 1 susceptibility protein (BRCA1) located on chromosome 17 and breast cancer type 2 susceptibility protein ( BRCA2 ) located on chromosome 13 are the most important genes associated with BC, with a 60% and 55%, respectively, cumulative risks.…”