CTNNB1 and colorectal carcinoma: For instance, genetic activation of the Wnt pathway was strongly associated with T-cell exclusion in CRC.497 In a mouse model of HCC, genetic activation of beta-catenin, the main mediator of Wnt signaling, promoted immune escape via defective recruitment of dendritic cells.498 Furthermore, activating gene alterations of the Ras-MAPK pathway were also found to mediate immune evasion.