Long non-coding RNA LINC00265 promotes proliferation, apoptosis, and inflammation of chondrocytes in osteoarthritis by sponging miR-101-3p

Long non-coding RNAs (lncRNAs) play a part in a wide variety of diseases, including osteoarthritis (OA). This study was designed to investigate the biological role of lncRNA LINC00265 in OA and its underlying mechanisms. We examined the levels of LINC00265 and miR-101-3p using RT-qPCR, inflammatory factors using ELISA, and caspase-3, c-caspase-3, Bcl-2, Bax, and MMP-13 levels using Western blot in normal and OA chondrocytes, analysed the relationship between LINC00265 and miR-101-3p using bioinformatics analysis and luciferase reporter assays, performed loss- and gain-of-function analyses. The results showed that (1) LINC00265 expression was increased in OA chondrocytes, (2) si-LINC00265 inhibited OA chondrocyte apoptosis and inflammation, and (3) LINC00265 overexpression promoted normal and OA chondrocyte apoptosis and inflammation. Furthermore, we predicted and confirmed that miR-101-3p was a target of LINC00265. LINC00265 negatively regulated miR-101-3p in OA chondrocytes and LINC00265 promoted OA and normal chondrocyte apoptosis <i>via</i> miR-101-3p. Overall, lncRNA LINC00265 regulates chondrocyte apoptosis by acting as a sponge of miR-101-3p in OA.

长链非编码RNA（Long non-coding RNAs，lncRNAs）广泛参与包括骨关节炎（osteoarthritis, OA）在内的多种疾病的发生发展。本研究旨在探讨长链非编码RNA LINC00265在骨关节炎中的生物学作用及其潜在分子机制。
本研究采用RT-qPCR检测正常软骨细胞与骨关节炎软骨细胞中LINC00265与miR-101-3p的表达水平，采用酶联免疫吸附试验（ELISA）检测炎性因子水平，采用蛋白质印迹法（Western blot）检测caspase-3、剪切型caspase-3、Bcl-2、Bax及基质金属蛋白酶13（MMP-13）的蛋白表达水平；通过生物信息学分析与双荧光素酶报告基因实验验证LINC00265与miR-101-3p的靶向调控关系，并开展功能缺失与功能获得性实验分析。
结果显示：① LINC00265在骨关节炎软骨细胞中表达显著上调；② 沉默LINC00265可抑制骨关节炎软骨细胞的凋亡与炎症反应；③ 过表达LINC00265可促进正常软骨细胞与骨关节炎软骨细胞的凋亡及炎症反应。
本研究进一步通过生物信息学预测并实验证实，miR-101-3p是LINC00265的靶基因；LINC00265在骨关节炎软骨细胞中负向调控miR-101-3p的表达，且LINC00265可通过靶向miR-101-3p促进正常与骨关节炎软骨细胞的凋亡。
综上，长链非编码RNA LINC00265可通过作为miR-101-3p的分子海绵，调控骨关节炎进程中软骨细胞的凋亡过程。