EWSR1 and Ewing sarcoma: Ewing sarcoma cell lines selected for these experiments were representative of the most frequent gene fusions observed in Ewing sarcoma, that is, A673 (EWSR1::FLI1 type 1 fusion, EWSR1 exon 7-FLI1 exon 6), MHH-ES1 (EWSR1::FLI1 type 2 fusion, EWSR1 exon 7-FLI1 exon 5), and CADO-ES1 (EWS::ERG fusion, EWS exon 7-ERG exon 8).