Frizzled-5

Frizzled-5 (FZD5) signals chiefly through the canonical Wnt/beta-catenin route after its cysteine-rich domain binds ligands such as Wnt8b, partnering with LRP5 or LRP6 coreceptors. The receptor is essential for eye development: Fzd5-null mice develop coloboma, a failure of the optic fissure to close, and human FZD5 variants have been associated with microphthalmia and coloboma spectrum disorders. FZD5 is also expressed in vasculature, where it contributes to angiogenic remodeling, and in placenta, skin and reproductive tissues. In oncology, FZD5 upregulation has been observed in gastric, colorectal and pancreatic cancers, where it promotes proliferation and stem-like properties, positioning it as a candidate for antibody-based Wnt pathway intervention.