Wnt signaling in B and T lymphocytes

Wnt signaling has been shown to be critical for proper embryonic development as well as growth regulation of certain adult tissues. Defects in Wnt pathways have additionally been associated with a number of human cancers. However, it is only recently that a role for Wnts in the immune system has come to be appreciated. Wnts have now been shown to play significant roles in early stage development of both B and T lineage cells. Current studies suggest that proliferation and/or survival of these cells is associated with activation of the 'canonical' Wnt/beta-catenin pathway. Functional Wnt signaling appears to also occur in end stage B (plasma) cells where both the 'canonical' and the Wnt/RhoA pathways are activated. Herein, we review the current understanding of Wnt signaling in B and T cell development and the potential involvement of Wnt cascades in lymphoid neoplasia.