The main issue addressed in this thesis is how different

levels of signaling activity of the Wnt and

TGF-β/BMP pathways can affect transcriptional responses

in particular relevant for self-renewal and differentiation

both in homeostasis and in cancer.

Chapter 1 presents an overview of the existent literature

leading to the formulation of the hypothesis

that Apc/Wnt pathway acts in a dosage-dependent

manner both in normal and neoplastic tissues