A novel circular RNA (hsa_circ_0000370) increases cell viability and inhibits apoptosis of FLT3-ITD-positive acute myeloid leukemia cells by regulating miR-1299 and S100A7A.

FLT3-ITD+ acute myeloid leukemia (AML) is an important subtype of AML, accounting for approximately 25 % of all AML cases in the world. Recently, increasing evidence has shown that circular RNAs (circRNAs) can act as effective biomarkers of various human cancers. However, the roles of circRNAs in AML remain largely unclear. In the present study, circ_0000370 was found to be significantly increased in FLT3-ITD+ AML and was demonstrated to act as an oncogenic circRNA of AML in vitro. TargetScan results showed that miR-1299, miR-370-3p, miR-502-5p, miR-1281 and miR-640 were potential targets of circ_0000370, and miR-1299 had the broadest range of interactome compared with other microRNAs of interest. Moreover, we demonstrated that S100A7A was a target gene of miR-1299, and circ_0000370 could regulate S100A7A expression by sponging miR-1299 in AML cell lines. Therefore, we suggest that the promoting effects of circ_0000370 on the progression of FLT3-ITD+ AML might be relevant to the inhibition of miR-1299 and the upregulation of S100A7A.