RARA and acute promyelocytic leukemia: They demonstrated that many recurrent chromosomal translocations, of PML/RARα observed in Acute Promyelocytic Leukemia (APL), MLL/AF9 in Acute Myeloid Leukemia (AML), EWSR1/FLI1 in Ewing Sarcoma and EML4/ALK1 associated with lung cancer could form f-circRNAs [226,227].