Moreover, Li et al. observed an increased level of genomic DNA of Fusobacterium nucleatum in the breast tissue of patients with breast cancer, also, small extracellular vesicles derived from F. nucleatum were found to increase breast cancer cell migration, invasion, and proliferation in vitro and metastasis in vivo, via TLR4, suggesting important role of breast tumor microbiota in the progression and metastasis of breast cancer [93]. Here, TLR4 is linked to breast cancer.