Based on the findings observed in the studies performed in the cancer cell cultures [27,31], we suggest that a molecular mechanism for activation of NADPH oxidase in colonic epithelial cells may be associated with a toll-like receptor (TLR) pathway, where LPS strains potently stimulate ROS production by colon NADPH oxidase through a TLR4 [31-33]. Here, FMO5 is linked to cancer.