IWP-2 is an inhibitor of Wnt processing and secretion with IC50 of 27 nM in a cell-free assay, selective blockage of Porcn-mediated Wnt palmitoylation, does not affect Wnt/β-catenin in general and displays no effect against Wnt-stimulated cellular responses. IWP-2 specifically inhibits CK1δ.