MiR-105 enhances osteogenic differentiation of hADSCs via the targeted regulation of SOX9.

Objective: To investigate whether miR-105 can regulate the osteogenic differentiation of human adipose-derived mesenchymal stem cells (hADSCs) by targeting SOX9.

Methods: The hADSCs were grouped for subsequent transfection and induction of osteogenic differentiation as follows: control, miR-NC, miR-105 mimics, miR-105 inhibitors, SOX9, SOX9 siRNA, miR-105 mimics + SOX9 and miR-105 inhibitors + SOX9 siRNA groups. Next, hADSCs were stained for alkaline phosphatase (ALP), and Alizarin Red S staining (ARS) was performed. Osteogenic differentiation-related genes and miR-105 expression were assessed by qRT-PCR, while SOX9 protein expression was determined by Western blotting.

Results: MiR-105 expression was increased and SOX9 protein expression was decreased during the osteogenic differentiation of hADSCs. A dual-luciferase reporter assay confirmed SOX9 to be a target gene of miR-105. Compared with the control group, the miR-105 mimics and SOX9 siRNA groups had elevated BMP2, OPN, OCN, BSP, Osx and Runx2 mRNA expression with reduced SOX9 expression, as well as increased ARS intensity and ALP activity. After transfection of miR-105 inhibitors/SOX9 into hADSCs, the results were the opposite. Overexpressing SOX9 reversed the effect of miR-105 in promoting the osteogenic differentiation of hADSCs.

Conclusion: MiR-105 could target SOX9 to improve the expression of osteogenic differentiation genes and thus enhance the osteogenic differentiation of hADSCs.