Transforming growth factor beta (TGF-β) is a protein that prevents normal cells from dividing. When a cell is transformed into a cancer cell, parts of the TGF-β signaling pathway are mutated. These cancer cells proliferate and TGF-β no longer controls the cell. How this occurs is currently unclear. We have identified a new mechanism that allows TGF-β to remove chemical groups from DNA thereby regulating gene expression. The goal of this proposal is to understand this mechanism and its implication in TGF-β signalling during tumour progression.