In this study we observed an unexpected phenomenon in a panel of breast and lung cancer cell lines that in spite of SMAD7 mRNA induction in immediate response to TGFβ, the protein abundance of SMAD7 was not elevated, or even slightly reduced following the stimulation (Fig. 1c), indicating the inefficiency of SMAD7-mediated feedback to restrain TGFβ signalling in these cancer cells and in the studied context. Here, TGFB1 is linked to cancer.