LAUSR

BACKGROUND Circular RNAs (circRNAs) are a specific family of non-coding RNAs (ncRNAs) with important function in disease progression. This research is performed to study circRNA Ring Finger Protein 220 (circRNF220) in acute myeloid leukemia (AML). METHODS CircRNF220, microRNA-330-5p (miR-330-5p) and sex-determining region Y-related high-mobility group box 4 (SOX4) were measured via quantitative real-time polymerase chain reaction (qRT-PCR). 3-(4, 5-dimethylthiazol-2-y1)-2, 5- diphenyl tetrazolium bromide (MTT) and EdU assays were used to assess cell proliferation. Cell cycle and apoptosis were detected using flow cytometry. Cell invasion was determined by transwell assay. Glycolytic metabolism was assessed by glucose consumption and lactate production. The target interaction was implemented via dual-luciferase reporter and RNA pull-down assays. SOX4 protein detection was conducted by western blot. RESULTS Expression detection identified that circRNF220 was overexpressed in AML. In vitro experiments showed that silence of circRNF220 promoted cell apoptosis but impeded proliferation, cell cycle progression, invasion and glycolytic metabolism in AML cells. Target analysis indicated that circRNF220 directly targeted miR-330-5p, and the effects of si-circRNF220 were abrogated by miR-330-5p inhibitor. Moreover, circRNF220 targeted miR-330-5p to increase the expression of SOX4 and SOX4 promoted cell progression of AML. CONCLUSION All these findings revealed that circRNF220 contributed to AML cell development in vitro via upregulating SOX4 expression by targeting miR-330-5p.