MSN and cancer: Given that human ortholog of Msn (MAP4K4) is overexpressed in various human cancers [46,47,48,49,50] and a number of Hippo pathway components regulate Hippo signaling in a negative feedback manner, including kibra, ex, wts [18,20,21,51], we utilized the Drosophila wing imaginal discs to explore whether Msn also functions as a Hippo pathway target gene.