Furthermore, the Jak/Stat ligand, Upd3, is also upregulated in the scrib− cells, where it drives tumour overgrowth, and is also required to activate Jak/Stat signalling in the wild-type neighbouring cells in cell competition (Bunker et al., 2015; Chen et al., 2012; Schroeder et al., 2013). This evidence concerns the gene SOAT1 and neoplasm.