Moreover, if clonal overexpression of a secreted form of EGF/Spitz (Spitzsc)44 in epithelial cells mostly induces a high rate of mortality during pupal stage, the remaining adult flies can display tumours exhibiting the same hallmarks of cell overgrowth and loss of epithelial markers as in RasV12 induced tumours (Fig. 7d). This evidence concerns the gene EGF and neoplasm.