miR-142-3p promotes osteoblast differentiation by modulating Wnt signaling

Canonical Wnt signaling is critical for the control of osteoblast differentiation in human mesenchymal stem cells. MicroRNAs (miRs) are essential regulators of cell differentiation by post-transcriptional regulation of target gene expression. The aim of the present study was to investigate the molecular mechanism by which miR-142-3p promotes osteoblastic differentiation. using the human fetal osteoblastic 1.19 (hFOB1.19), real-time PCR and western blot analysis. Results showed an increased expression of miR-142-3p during osteoblast differentiation in the mesenchymal precursor cell line, hFOB1.19. In addition, the ectopic overexpression of miR-142-3p promoted hFOB1.19 differentiation, whereas the inhibition of miR-142-3p repressed differentiation. The expression of miR-142-3p was positively correlated with P-catenin, an important protein in Wnt signaling. The adenomatous polyposis coli (APC) gene was a direct target of miR-142-3p, whereby miR-142-3p promoted Wnt signaling through inhibition of APC, leading to accumulation and nuclear translocation of p-catenin. Therefore, miR-142-3p may be an essential mediator of osteoblast differentiation and a new therapeutic strategy for osteogenesis disorders.