Ki20227 is a selective inhibitor of the TGF-β receptor kinase, primarily used in research settings to study signaling pathways involved in fibrosis, cancer progression, and epithelial-mesenchymal transition (EMT). It is commonly applied in cellular and molecular biology experiments to suppress TGF-β-mediated responses, helping to elucidate the role of this pathway in disease mechanisms. Due to its specificity, Ki20227 is valuable in screening studies aimed at developing anti-fibrotic or anti-cancer therapies. It is also used in combination with other inhibitors to modulate stem cell differentiation, particularly in induced pluripotent stem cell (iPSC) cultures, where blocking TGF-β signaling supports more controlled lineage specification.