SB431542 is widely used in biological research to inhibit the TGF-β signaling pathway. It specifically targets and blocks the activity of TGF-β type I receptors, ALK4, ALK5, and ALK7. This inhibition is crucial in studies focused on understanding cellular processes such as differentiation, proliferation, and apoptosis. Researchers frequently employ SB431542 to maintain pluripotency in stem cell cultures, as it prevents differentiation induced by TGF-β signaling. Additionally, it is utilized in cancer research to study the role of TGF-β in tumor progression and metastasis. Its ability to modulate TGF-β pathways also makes it valuable in fibrosis research, where it helps in exploring potential therapeutic strategies. Overall, SB431542 is a key tool in elucidating the complex roles of TGF-β signaling in various biological contexts.