In a previous study comparing host cell gene expression profiles with oral microbial profiles within patients with OLP and healthy individuals, researchers found that Corynebacterium matruchotii, Fusobacterium periodonticum, and other species were capable of activating the Hepatocyte nuclear factor-alpha (HNF4A) gene network, which mediates mucosal inflammatory processes [21]. The gene discussed is HNF4A; the disease is oral lichen planus.