SCRIB and neoplasm: As another MEK inhibitor, trametinib, is a widely used, orally administered drug for the treatment of Ras-driven human cancers (Ferrari et al., 2020; Hoffner and Benchich, 2018; Manoharan et al., 2020; Tabbò et al., 2022; Wright and McCormack, 2013; Zeiser, 2014), we tested whether it was also effective in reducing tumour size of scrib mutant, RasV12-expressing (scrib−/RasV12) larvae when administered in the food, as measured by changes in the size of the GFP-marked eye-antennal discs, which overgrow substantially upon induction of scrib−/RasV12 clone generation (Fig. 1A).