Several possible mechanisms have been suggested in regard to the role of oral microbiota in cancer pathogenesis: (i) stimulation of local and/or systemic chronic inflammation, during which the inflammatory mediators initiate or facilitate cell proliferation and mutagenesis; (ii) the activation of NF-κB and apoptosis inhibition; or (iii) the production of some carcinogenic substances [42]. This evidence concerns the gene NFKB1 and cancer.