Background: Recent studies have reported the vital roles of circular RNAs (circRNAs) in
tumor progression. However, the function and expression profile of most circRNAs in osteosarcoma
Methods: We examined the expression of circEPSTI1, a circRNA, in 50 paired adjacent normal tissues
and osteosarcoma tissues by qRT-PCR. Then, we further explored the function of circEPSTI1
in osteosarcoma progression in vitro and in vivo. For example, cell proliferation and migration were
examined. Some experiments were performed to explore the regulatory function of circEPSTI1 in
miRNA and to investigate the potential role of circEPSTI1 in osteosarcoma.
Results: We found that circEPSTI1 was significantly upregulated in osteosarcoma. Inhibition of circEPSTI1
suppressed the osteosarcoma cancer cell proliferation and migration in vitro. Dual luciferase
reporter assay showed that circEPSTI1 and MCL1 (myeloid cell leukaemia 1) could bind to
miR-892b and that MCL1 and circEPSTI1 were targets of miR-892b.
Conclusion: Thus, the circEPSTI1-miR-892b-MCL1 axis affected osteosarcoma progression
through the miRNA sponging mechanism. circEPSTI1 may serve as a target and biomarker for osteosarcoma