The concern was basically excluded, since YAP or YAPdeltaC even at high expression levels (Supplementary Fig. 7A) did not induce tumor-like foci (Supplementary Fig. 7B) or did not increase the number of cells positive for Ki67 (a tumor marker) and Sox2 (a de-differentiation marker), as revealed by immunohistochemistry (Supplementary Fig. 7C) or western blot analysis (Supplementary Fig. 7D). This evidence concerns the gene SOX2 and neoplasm.