WIF1 and lung carcinoma: Expression of the Wnt ligand, low-density lipoprotein receptor–related protein 5 (LRP5), and LRP6 are upregulated in lung cancers, whereas Wnt antagonists that bind Wnt ligands to block interaction with receptors (e.g., Wnt inhibitory factor-1 (WIF-1), secreted Frizzled-related proteins (sFRP) and dickkopf proteins (DKK) are downregulated or inactivated [9], [10].