Cancer cells must undergo substantial adaptations, such asincreased motility and immune evasion, to be able to migrate to andcolonize other parts of the body.5SMAD4 is a key driver gene for CRC progression, and inactivatingmutations that are observed in 5–24.2% of CRC cases are associatedwith the promotion of metastatic trait development.6 The main effects of SMAD4 inactivation on tumor developmentare thought to occur by regulation of the TGFβ pathway. The gene discussed is TGFB1; the disease is colorectal carcinoma.