ROR2 (Receptor Tyrosine Kinase-like Orphan Receptor 2) is broadly expressed during embryonic development and can be found in cells of all three germ layers as well as in most organ tissues. It binds Wnt-5a to promote cellular proliferation, differentiation, polarization, and migration. It is important for osteogenic and chondrogenic differentiation of mesenchymal stem cells, and mutations in ROR2 are associated with the skeletal disorders brachydactyly type B and Robinow syndrome. It is also involved in neurite outgrowth and synapse development in the brain. ROR2 is overexpressed in a variety of cancers where it can act as a tumor suppressor or promoter.