FOXO1 and Ewing sarcoma: Besides, negative regulation of FoxO1 activity and nuclear localization, caused by CDK2 (a negative regulator of EWS–FLI1-induced FoxO1 transcriptional activity) and PI3K/Akt-mediated FoxO1 phosphorylation, accelerated proliferation and promoted soft agar colony formation in two Ewing sarcoma cell lines (A673sh and SK-N-MC) (Niedan et al., 2014).