text: The Wnt protein family includes a large number of cysteine-rich glycoproteins. The Wnt proteins activate signal transduction cascades via three different pathways, the canonical Wnt pathway, the noncanonical planar cell polarity (PCP) pathway, and the noncanonical Wnt/Ca pathway. Wnt proteins appear to control a wide range of developmental processes and have been seen as necessary for control of spindle orientation, cell polarity, cadherin mediated adhesion, and early development of embryos in many different organisms. Current research has indicated that deregulation of Wnt signaling plays a role in tumor formation, because at a cellular level, Wnt proteins often regulated cell proliferation, cell morphology, cell motility, and cell fate.