Design, synthesis, and evaluation of potent Wnt signaling inhibitors featuring a fused 3-ring system

Abstract

The Wnt signaling pathway is a critical developmental pathway which operates through control of cellular functions such as proliferation and differentiation. Aberrant Wnt signaling has been linked to the formation and metastasis of tumors. Porcupine, a member of the membrane-bound O-acyltransferase family of proteins, is an important component of the Wnt pathway. Porcupine catalyzes the palmitoylation of Wnt proteins, a process needed for their secretion and activity. Here we report a novel series of compounds obtained by a scaffold hybridization strategy from a known porcupine inhibitor class. The leading compound 59 demonstrated subnanomolar inhibition of Wnt signaling in a paracrine cellular assay. Compound 59 also showed excellent chemical, plasma and liver microsomal stabilities. Furthermore, compound 59 exhibited good pharmacokinetic profiles with 30% oral bioavailability in rat. Collectively, these results strongly support further optimization of this novel scaffold to develop better Wnt pathway inhibitors.

Keywords: Antagonist; Cancer therapy; Porcupine; Scaffold hybridization; Wnt signaling pathway.