Department of Joint Surgery, Rizhao Central Hospital, Rizhao, 276800, Shandong, China.
Department of Orthopedics, Peking University Medical Zibo Hospital, Zibo, 255069, Shandong, China.
J Orthop Surg Res. 2021 Apr 13;16(1):253. doi: 10.1186/s13018-021-02391-9.
Circular RNA (circRNA) has been shown to be associated with osteoarthritis (OA) progression. Circ_0116061 has been found to be highly expressed in OA cartilage tissues, but its role and mechanism in OA progression remain unclear.
Expression levels of circ_0116061, microRNA (miR)-200b-5p, and Smad ubiquitin regulatory factor 2 (SMURF2) were detected using quantitative real-time PCR. The proliferation and apoptosis of cells were measured using cell counting kit 8 (CCK8) assay, colony formation assay, and flow cytometry. Furthermore, the protein levels of proliferation-related marker, apoptosis-related markers, inflammatory factors, and SMURF2 were tested using western blot (WB) analysis. In addition, the interaction between miR-200b-3p and circ_0116061 or SMURF2 was examined using dual-luciferase reporter assay and biotin-labeled RNA pull-down assay.
Circ_0116061 and SMURF2 were highly expressed, and miR-200b-3p was lowly expressed in OA cartilage tissues. Knockdown of circ_0116061 could promote the proliferation and inhibit the apoptosis and inflammation of OA chondrocytes. MiR-200b-3p could be sponged by circ_0116061, and its inhibitor could reverse the regulation of circ_0116061 silencing on the biological functions of OA chondrocytes. SMURF2 was a target of miR-200b-3p, and its expression was positively regulated by circ_0116061. Silencing of SMURF2 also could enhance the proliferation and suppress the apoptosis and inflammation of OA chondrocytes. Furthermore, the regulation of circ_0116061 silencing on the biological functions of OA chondrocytes also could be reversed by SMURF2 overexpression.
Our data showed that circ_0116061 might regulate the miR-200b-3p/SMURF2 axis to promote the progression of OA.
环状 RNA（circRNA）已被证明与骨关节炎（OA）的进展有关。已经发现 circ_0116061 在 OA 软骨组织中高度表达，但它在 OA 进展中的作用和机制尚不清楚。
使用实时定量 PCR 检测 circ_0116061、微小 RNA（miR）-200b-5p 和 Smad 泛素调节因子 2（SMURF2）的表达水平。使用细胞计数试剂盒 8（CCK8）测定、集落形成测定和流式细胞术测量细胞的增殖和凋亡。此外，使用 Western blot（WB）分析测试增殖相关标志物、凋亡相关标志物、炎症因子和 SMURF2 的蛋白水平。另外，使用双荧光素酶报告基因检测和生物素标记的 RNA 下拉实验检测 miR-200b-3p 与 circ_0116061 或 SMURF2 的相互作用。
OA 软骨组织中 circ_0116061 和 SMURF2 高表达，miR-200b-3p 低表达。circ_0116061 敲低可促进 OA 软骨细胞的增殖，抑制其凋亡和炎症。miR-200b-3p 可被 circ_0116061 海绵化，其抑制剂可逆转 circ_0116061 沉默对 OA 软骨细胞生物学功能的调节。SMURF2 是 miR-200b-3p 的靶基因，其表达受 circ_0116061 的正向调节。沉默 SMURF2 也可增强 OA 软骨细胞的增殖，抑制其凋亡和炎症。此外，SMURF2 过表达也可逆转 circ_0116061 沉默对 OA 软骨细胞生物学功能的调节。
我们的数据表明，circ_0116061 可能通过调节 miR-200b-3p/SMURF2 轴促进 OA 的进展。
