APC and gastric cancer: The Wnt/β-catenin pathway is often abnormally activated in GI cancers, especially in CRC and GC, resulting in mutations in genes such as APC or β-catenin, leading to increased β-catenin levels and its translocation into the nucleus, where β-catenin binds to TCF/LEF transcription factors, activating the transcription of genes involved in cell proliferation, survival, and metastasis.