To minimize inter-tumor heterogeneity that could result from inducing tumors with different NBs of origin, tumors were induced from the early L2 stage, when NBs exit quiescence, by knocking down pros in the six homologous poxn NBs of the VNC (one per hemisegment) using the poxn-Gal4, UAS-prosRNAi, UAS-GFP, UAS-dicer2 system - thereafter referred to as poxn > prosRNAi. This evidence concerns the gene PROS1 and neoplasm.