A context dependent role for Wnt signaling in tumorigenesis and stem cells.

The Wnt signal transduction pathway coordinates myriad activities, from development and differentiation to proliferation and tumorigenesis. What is perhaps most remarkable is that Wnt signaling is able to accomplish this diverse set of activities in a cell-specific and differentiation stage-dependent manner. In this review, we will highlight the diverse effect of Wnt signaling on three types of tissue stem cells and their corresponding malignancies.