Effect of gastrointestinal microbiome and its diversity on the expression of tumor-infiltrating lymphocytes in breast cancer.

Abstract

e14187 Background: The diversity of gastrointestinal microbiome is closely related to human health. In the present study, we compared gastrointestinal microbiome and tumor-infiltrating lymphocytes (TILs) in breast cancer (BC) patients. Methods: A total of 80 BC patients were divided into three groups based on the expression of TILs as follows: high expression of TILs (TIL-H), medium expression of TILs (TIL-M) and low expression of TILs (TIL-L). DNA of gastrointestinal microbiome was determined by Illumina sequencing and taxonomy of 16S rRNA genes. Kruskal-Wallis test and UniFrac analysis of β-diversity were applied to assess the relationship between patients’ clinical characteristics and diversity of gastrointestinal microbiome. Results: The β-diversity distribution was statistically significant (weighted UniFrac P < 0.01, unweighted UniFac P < 0.01) when comparing between the TIL-L and TIL-H groups or among the three groups (TIL-H vs. TIL-M vs. TIL-L). At the genus level, higher abundances of Mycobacterium, Rhodococcus, Catenibacterium, Bulleidia, Anaerofilum, Sneathia, Devosia and TG5 but lower abundances of Methanosphaera and Anaerobiospirillum ( P < 0.05) were identified in the TIL-L group compared with the TIL-H group . At the species level, the species of stercoris, barnesiae, coprophilus, flavefaciens and C21_c20 displayed a higher abundance in the TIL-L group, while producta and komagatae exhibited a greater abundance in the TIL-H group ( P < 0.05). Conclusions: Collectively, the diversity of gastrointestinal microbiome was related to the expression of TILs in BC patients.