Circ_0006873 suppresses the osteogenic differentiation of human‐derived mesenchymal stem cells through mediating miR‐20a/SMURF2 axis in vitro

Abstract

The clinical application of human‐derived mesenchymal stem cells (hMSCs) in osteoporosis (OP) treatment is promising. We aimed to uncover the role of circular RNA 0006873 (circ_0006873) in OP progression using hMSCs. The levels of circ_0006873, pantothenate kinase 2 (PANK2) messenger RNA (mRNA), microRNA‐20a (miR‐20a), SMAD specific E3 ubiquitin protein ligase 2 (SMURF2) mRNA and the mRNA levels of osteogenesis‐related markers were measured by quantitative real‐time polymerase chain reaction (qRT‐PCR). The protein expression of osteogenesis‐related markers and SMURF2 was detected by Western blot assay. Alkaline phosphatase (ALP) staining and activity were determined using an ALP staining Kit and an ALP Colorimetric Assay Kit. Circ_0006873 was highly expressed in the serum samples and bone tissue samples of OP patients compared with control cases. Circ_0006873 overexpression down‐regulated the expression of osteogenesis‐related markers and reduced ALP staining and activity. Circ_0006873 down‐regulated miR‐20a level through its interaction with miR‐20a in hMSCs. Circ_0006873 suppressed osteogenic differentiation through targeting miR‐20a. SMURF2 was a molecular target of miR‐20a, and miR‐20a promoted osteogenic differentiation through targeting SMURF2. Circ_0006873 suppressed the osteogenic differentiation of hMSCs by upregulating SMURF2 level via sponging miR‐20a in vitro.