Figure 2From: Transforming growth factor-β and breast cancer: Lessons learned from genetically altered mouse modelsTransforming growth factor (TGF)-β has direct and indirect effects on morphogenesis and function of the mammary epithelium. TGF-β acts directly on the epithelium to prevent precocious alveolar development and milk protein production in virgin mice. Acting indirectly, via the stroma, it may inhibit ductal branching, possibly through effects on activity of the morphogen hepatocyte growth factor.Back to article page