FLI1 and Ewing sarcoma: EWSR1 is known to form fusion genes with FLI1 in Ewing sarcoma, where the fusion protein promotes the phosphorylation of tyrosine397 of adhesion kinase by increasing the expression of Ezrin, and ultimately facilitates anoikis resistance and metastasis.33 In our study, we confirmed the presence of EWSR1:FLI1 fusion in BLCA cells by Sanger sequencing (Fig. S4), and found that NR4A3 overexpression inhibited the expression of the fusion gene and its downstream target Ezrin.