HPI-1 (599150-20-6) is a Hedgehog pathway inhibitor acting downstream of Smo and independently of PKA, PI3K and MAPK. It can suppress Hh pathway activation induced by loss of Su(fu) or Gli overexpression. HPI-1 inhibits both endogenous and exogenous Gli1/Gli2 activity. IC50's range from 0.2 to 6 μM for various cell-based assays.
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