HhAntag (HhAntag-691) is a potent, specific, and orally active small molecule Smoothened (Smo) antagonist, inhibits Sonic Hedgehog (Shh) pathway. HhAntag inhibits Gli1 expression in a dose-dependent manner in tumor tissue in vivo. HhAntag at 20 or 100 mg/kg of body weight, by oral gavage, for 4 days, inhibited tumor cell proliferation and increased apoptosis. HhAntag inhibits not only hedgehog signaling, but also modulates canonical and non-canonical BMP signaling and blocks basal and rhBMP2-stimulated chondrogenesis
