FH535 is a potent, reversible dual inhibitor of Wnt/β-catenin and a PPARγ and PPARδ signaling. FH535 antagonizes both PPARg and PPARδ ligand-dependent activation and shows structural similarity to GW9662, a known PPARgamma antagonist. The compound is selectively toxic to some carcinomas expressing the Wnt/β-catenin pathway.