FOXO1 and neoplasm: Conversely, EWS-FLI1 reduces the expression of genes involved in tumor suppressor mechanism (ex: apoptosis), such as FOXO1 (Forkhead Box O1) (Yang et al., 2010), or IER3 (Immediate Early Response 3) (Tsafou et al., 2018), tumor suppressor genes regulating mechanisms such as DNA repair, cell cycle arrest and apoptosis.