FOXO3 and neuroblastoma: In relation to the high-stage-derived cell lines the phosphorylation of FOXO3 at the PKB sites T32 and S253 was low in the NB cell lines SH-EP, STA-NB3 and IMR32 and consistently these cell lines also showed moderate to low PKB phosphorylation at the activating site PKB-serine-473 (S473).