CBS cells have been shown to be similar to the FETα engineered cells in that they have constitutive EGFR activation in addition to the attenuation of TGFβ tumor suppressor activity [38,49], thus providing a mechanism for retention of the capability of forming an invasive cancer at the primary site despite TGFβ activity generated by ectopic expression of the TGFβRII. The gene discussed is TGFB1; the disease is cancer.