Adverse Outcome Pathway (AOP) 298, entitled "increase in reactive oxygen species (ROS) leading to human treatment-resistant gastric cancer," consists of "increase in ROS" as a molecular initiating event (MIE), followed by a series of key events (KEs), namely "porcupine-induced Wnt secretion and Wnt signaling activation," "beta-catenin activation," and "epithelial-mesenchymal transition (EMT)," and the adverse outcome (AO) of "treatment-resistant gastric cancer" in the sequence. Here, CTNNB1 is linked to gastric cancer.