Many oncoproteins generated by gene fusion are strong drivers of tumorigenesis.[244] Intriguingly, gain of LLPS ability has been implicated in the cancer pathology of such fusion oncoproteins.[188, 245] In Ewing sarcoma, the well‐characterized oncoprotein EWS‐FLI1, which is produced by the fusion of the N‐terminal IDRs of EWS RNA binding protein 1 (EWSR1) and the DNA‐binding domain of friend leukemia virus integration site 1 (FLI1), acquires LLPS ability compared to wild‐type FLI1. This evidence concerns the gene EWSR1 and cancer.