The present invention relates to compounds and methods for treating cancers in which the autocrine Wnt canonical signaling pathway is activated. In particular, there is provided a method for inhibiting growth of a tumor cell or sensitizing a cancer cell to treatment by contacting such a tumor cell with a compound that alters Wnt signaling. The compound that alters Wnt signaling can be a Wnt antagonist, a Wnt receptor antagonist, or a combination thereof.