Circular RNA circ_0079593 promotes glioma development through regulating KPNA2 expression by sponging miR-499a-5p.

ABSTRACT

OBJECTIVE: Glioma is a common aggressive cancer and a major public health problem worldwide, with high incidence, recurrence, and mortality. Circular RNA (circRNA) has been reported to be involved in glioma, but the role of circ_0079593 in glioma is still unclear. MATERIALS AND METHODS: The real-time quantitative polymerase chain reaction (RT-qPCR) was performed to quantify the expression levels of circ_0079593, miR-499a-5p, and karyopherin alpha 2 (KPNA2) in glioma tissues or cells. The protein expression level of KPNA2 was assessed by Western blot. 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazol-3-ium bromide (MTT), flow cytometry, and transwell assays were conducted to evaluate proliferation, apoptosis, migration and invasion of glioma cells, respectively. The relationship between miR-499a-5p and circ_0079593 or KPNA2 was analyzed by bioinformatics database and confirmed by Dual-Luciferase reporter analyses, respectively. The effects of circ_0079593 silencing in vivo were measured by a xenograft experiment. RESULTS: Circ_0079593 and KPNA2 were elevated in glioma tissues and cells. Loss-of functional experiments revealed that knockdown of circ_0079593 hampered the progression of glioma by repressing proliferation, motility and inducing apoptosis in vitro and declining tumor growth in vivo. Similarly, suppression of KPNA2 impeded the process of glioma by inhibiting proliferation, motility and increasing apoptosis. MiR-499a-5p, interacting with KPNA2, was a target gene of circ_0079593. In addition, overexpression of KPNA2 could reverse the effects of circ_0079593 knockdown on proliferation, apoptosis, migration and invasion of glioma cells. Mechanistically, circ_0079593 mediated proliferation, motility and apoptosis of glioma cells by regulating KPNA2 expression via sponging miR-499a-5p. CONCLUSIONS: Circ_0079593 stimulated the pathological process of glioma via acting as competing endogenous RNA to sponge miR-499a-5p.