KRT7 and colorectal carcinoma: Even if the bacterium is an oral resident, it may enter the intestinal tissues through the digestive tract or bloodstream and exert pro-inflammatory and cytotoxic effects through lipopolysaccharide (LPS), keratin-7 antisense (KRT7-AS), miRNA, the adhesins FadA, Fap2 (8), hydrogen sulfide (H2S), and alteration of intestinal microbiota to resulting in the development of diseases, such as CRC.