Cyclopamine is a potent and selective inhibitor of the hedgehog signaling with an IC50 ~46 nM, acting as an antagonist of Smoothened. It is a natural product isolated from the corn lily (Veratrum californicum). As the hedgehog signaling pathway plays very important roles in embryogenesis and cancer progression, Cyclopamine has been used in stem cell differentiation, such as pancreatic cell differentiation from ESC/iPSC, or treating Hh pathway dependent cancer in vitro and in vivo.