SMO and cancer: Specifically, Bacteroides fragilis produces toxins that activate pathways such as NF-κB, SMO, Wnt/β-catenin, and Notch1, in addition to inducing reactive oxygen species (ROS) and DNA damage, all of which contribute to cancer progression (Parida et al., 2021; Cheng et al., 2020; Sears et al., 2014).