CIRC_0091822 CONTRIBUTES TO THE PROLIFERATION, INVASION, AND MIGRATION OF VASCULAR SMOOTH MUSCLE CELLS UNDER OXIDIZED LOW-DENSITY LIPOPROTEIN TREATMENT.

Background: Circular RNAs (circRNAs) have been shown to mediate atherosclerosis (AS) process by regulating vascular smooth muscle cells (VSMCs) function. However, whether circ_0091822 mediates VSMCs function to regulate AS process is unclear. Methods: Oxidized low-density lipoprotein (ox-LDL) was used to treat VSMCs for constructing AS cell models. Vascular smooth muscle cells proliferation, invasion, and migration were examined by cell counting kit 8 assay, EdU assay, transwell assay, and wound healing assay. Protein expression was tested by western blot analysis. The expression of circ_0091822, microRNA (miR)-339-5p, and blocking of proliferation 1 (BOP1) was determined using quantitative real-time PCR. RNA interaction was examined using dual-luciferase reporter assay and RIP assay. Results: Ox-LDL treatment enhanced VSMCs proliferation, invasion, and migration. Circ_0091822 was overexpressed in the serum of AS patients and ox-LDL-induced VSMCs. Circ_0091822 knockdown inhibited ox-LDL-induced VSMCs proliferation, invasion, and migration. Circ_0091822 sponged miR-339-5p, and miR-339-5p inhibitor reversed the function of circ_0091822 knockdown. MiR-339-5p targeted BOP1, and BOP1 also reversed the repressing effect of miR-339-5p on ox-LDL-induced VSMCs functions. Circ_0091822/miR-339-5p/BOP1 axis promoted the activity of Wnt/β-catenin pathway. Conclusions: Circ_0091822 might be a therapeutic target for AS, which facilitated ox-LDL-induced VSMCs proliferation, invasion, and migration through modulating miR-339-5p/BOP1/Wnt/β-catenin pathway.