Dkk-3 (Dickkopf-3) is a member of the dickkopf family. It is a 350 amino acid secreted glycoprotein that is composed of an N-terminal signal peptide and two conserved cysteine-rich
domains, which are separated by a 12 amino acid linker region. This secreted protein is involved in embryonic development through its interactions with the Wnt signaling pathway. The e, Xenopus/Amphibian,pression of this protein is decreased in a variety of cancer cell lines and it may function as a tumor suppressor gene.