A novel fusion circRNA (F-circM9) was found to be only present in leukemia cells where MLL/AF9 gene translocation occurs, and expression of F-circM9 promotes leukemia cell proliferation 42; circPTCH1 promoted renal cell carcinoma (RCC) metastasis via the miR-485-5p/MMP14 axis and activation of the EMT process and targeting circPTCH1 may represent a promising therapeutic strategy for metastatic RCC 43. This evidence concerns the gene MLLT3 and leukemia.