DLX2 activates Wnt1 transcription and mediates Wnt/β-catenin signal to promote osteogenic differentiation of hBMSCs

Objectives: The molocular mechanism underlying human bone marrow mesenchymal stem cells (hBMSCs) differentiation remains to be further elucidated. DLX2 has been confirmed to accelerate osteogenic differentiation which is one member of Distal-less family genes. However, how DLX2 regulates in osteogenic differentiation is still unclear. Methods: The hBMSCs were isolated and identified by the antigen CD29, CD4, CD90 through flow cytometry. DLX2 expression level, molecules related signaling pathways and transcriptional markers in osteogenesis were examined by western blot and real time-PCR. Osteogenic state was weighed by the ALP Detection Kit and Alizarin red S staining. The combination between DLX2 and WNT1 was detected by Chromatin immunoprecipitation (CHIP) assay. Results: The results showed that in the process of osteoblast differentiation, DLX2 was up-regulated accompanied with osteogenic transcriptional factor. DLX2 elevated cellular alkaline phosphatase activity, accelerated BMSC mineralization along with up-regulation of osteogenic-related gene expression. Besides, DLX2 is a transcription factor of WNT1, which activated the Wnt/beta-Catenin signaling pathway resulting in osteogenic differentiation. Whereas, the inhibitor of beta-Catenin FH535 restrained enhanced osteogenic capability induced by DLX2. Conclusions: Taken together, these results suggest that by up-regulation of Wnt/beta-Catenin signaling, DLX2 accelerated human osteogenic differentiation.