The TGF-β/SMAD4 signaling pathway, which interacts with other classical pathways, such as MAPK, PI3K/AKT, and WNT/β-catenin, can influence cancer initiation and progression through multiple mechanisms, such as apoptosis, DNA damage repair and epithelial-mesenchymal transition (67, 68). The gene discussed is TGFB1; the disease is cancer.