Although the causality and underlying mechanisms remain to be elucidated, it has been demonstrated that FadA adhesin of F. nucleatum could promote bacterial attachment and invasion into E-cadherin expressing CRC cells, subsequently activating β-catenin-regulated transcriptions, as shown by upregulation of lymphoid enhancer factor/T cell factor, host NF-κB, oncogene c-Myc and cyclin D1, consequently promoting CRC cell proliferation and inflammation (Rubinstein et al., 2013). Here, CCND1 is linked to colorectal carcinoma.