The first factor is Fusobacterium adhesin A (FadA), which is also an important kinase in OSCC, induces oncogenic gene expression and promotes the growth of CRC cells; the other factor, namely, Fap2, which is derived from F. nucleatum, potentiates the progression of CRC by its inhibiting potential for immune cell activity through interacting with T-cell immunoreceptors with Ig and ITIM domains (TIGIT) [81,82]. Here, TIGIT is linked to colorectal carcinoma.