TGFb activation is closely linked to epithelial-to-mesenchymal transition (EMT), a process that increases invasion and migration of cancer cells and is central to the metastatic process.4 However, EMT is a highly plastic and transient state, and it is generally believed that cancer cells revert to a more epithelial state once they have colonised the target organ. The gene discussed is TGFB1; the disease is cancer.