These xenograft mouse transplantation experiments finally clearly demonstrated the “Janus-faced” nature of FOXO3 in NB: NB15/FOXO3 tumors in carrier-only treated animals exhibited significant vascularization and/or vessel permeability whereas 4OHT-treated animals had small tumors with few cancer cells (Figures 5A and 5C). The gene discussed is FOXO3; the disease is cancer.