Yang Jizhou, Wang Shaojie, Wang Fengxian, Mu Xiaohong, Qu Yi, Zhao Ziyi, Yu Xing
Department of Orthopaedics, Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine, Beijing 100700, P.R. China.
Department of Orthopaedics, Dongfang Hospital, Beijing University of Chinese Medicine, Beijing 100078, P.R. China.
Int J Mol Med. 2017 Jun;39(6):1605-1612. doi: 10.3892/ijmm.2017.2955. Epub 2017 Apr 20.
MicroRNAs (miRNAs or miRs) have been shown to play a critical role in osteoblast differentiation. miR-10b has been found to be downregulated during osteoblast differentiation; however, its precise effect on osteoblast differentiation remains unknown. In this study, we aimed to investigate the potential role of miR-10b and the potential underlying mechanism in regulating osteoblast differentiation. We found that miR-10b was downregulated during osteoblast differentiation. Overexpression of miR-10b inhibited osteoblast differentiation, whereas the suppression of miR-10b promoted osteoblast differentiation. Bioinformatics analysis and the dual-luciferase reporter assay demonstrated that miR-10b could target the 3'-untranslated regions of B cell lymphoma 6 (Bcl6) which is an important regulator of osteoblast differentiation. Real‑time quantitative polymerase chain reaction and western blot analysis showed that miR-10b directly regulated Bcl6 expression. Further experiments showed that the overexpression of miR-10b increased the expression of signal transducer and activator of transcription 1 (STAT1) and blocked Runt-related transcription factor 2 (Runx2) nuclear translocation, whereas miR-10b suppression showed an opposite effect. Moreover, the miR-10b suppression-induced effects were partially reversed by Bcl6 knockdown. Taken together, our study suggests that miR-10b contributes to osteoblast differentiation through targeting Bcl6, providing a novel insight into understanding the molecular mechanism underlying osteoblast differentiation and suggesting a potential target for inhibiting bone loss.
微小RNA（miRNA或miR）已被证明在成骨细胞分化中起关键作用。研究发现，miR-10b在成骨细胞分化过程中表达下调；然而，其对成骨细胞分化的确切作用仍不清楚。在本研究中，我们旨在探讨miR-10b在调节成骨细胞分化中的潜在作用及潜在机制。我们发现miR-10b在成骨细胞分化过程中表达下调。过表达miR-10b可抑制成骨细胞分化，而抑制miR-10b则促进成骨细胞分化。生物信息学分析和双荧光素酶报告基因检测表明，miR-10b可靶向B细胞淋巴瘤6（Bcl6）的3'非翻译区，而Bcl6是成骨细胞分化的重要调节因子。实时定量聚合酶链反应和蛋白质免疫印迹分析表明，miR-10b直接调节Bcl6的表达。进一步实验表明，过表达miR-10b可增加信号转导和转录激活因子1（STAT1）的表达，并阻断Runx相关转录因子2（Runx2）的核转位，而抑制miR-10b则产生相反的效果。此外，抑制miR-10b诱导的效应可被Bcl6基因敲低部分逆转。综上所述，我们的研究表明，miR-10b通过靶向Bcl6促进成骨细胞分化，为理解成骨细胞分化的分子机制提供了新的见解，并提示了一个抑制骨质流失的潜在靶点。
