Dickkopf related protein 2 (Dkk-2) is a member of the Dickkopf family of secreted Wnt modulators. Dkk proteins modify Wnt engagement of a receptor complex composed of a Frizzled protein and either LRP-5 or LRP-6. Kremen-1 and Kremen-2 are also high affinity receptors for Dkk-1 and Dkk-2. Depending on the cellular context, Dkk-2 can either activate or inhibit canonical Wnt signaling. Dkk proteins are expressed in mesenchymal tissues and control epithelial transformation. Dkk-2 expression is induced by Wnts in bone and is thought to enhance bone density by promoting terminal differentiation of osteoblasts and mineral deposition.