MAP2K7 and neoplasm: To identify the most effective inhibitor against RasG12V tumours, we targeted transgenes to the developing hindgut using byn-GAL4 and performed a limited FDA drug screen: the potent and specific MEK inhibitor trametinib was especially effective in reducing oncogenic RasG12V-mediated transformation in the Drosophila hindgut, leading to increased animal survival (Supplementary Fig. S1a, b).