FOXO3 and neuroblastoma: To investigate, how drug treatment affects FOXO3-phosphorylation and whether some cell lines feature the same FOXO3 phosphorylation phenotype as stage IV NB tumors in situ, we analyzed the phosphorylation status of endogenous PKB and FOXO3 in etoposide- and doxorubicin-treated SH-EP, STA-NB1 and STA-NB15 cells.