Secreted Wnt glycoproteins are one of the major families of cell signaling molecules and have a dual role in embryogenesis and carcinogenesis.Wnt proteins signals act through canonical pathway and non-canonical pathway.Wnt ligands bind to two distinct families of cell-surface receptors: the Frizzled(Fz) receptor family and the LDL-receptor related protein(LRP) family.Wnt-mediated signals are modulated extracellularly by Wnt antagonists.Wnt antagonists are asecreted proteins that bind to Wnt proteins and inhibit their activities.They can be divided into two groups: one is sFRP family,WIF-1 and Cerberus,another is DKK family.Wnt signaling has clearly emerged as a critical pathway in carcinogenesis.It deserves further study on the components of the Wnt pathway to provide valuable targets for potential anti-cancer therapeutic agents.