MiR-144-3p regulates osteogenic differentiation and proliferation of murine mesenchymal stem cells by specifically targeting Smad4.

Despite extensive research on osteoblast differentiation and proliferation in mesenchymal stem cells (MSCs), the accurate mechanism remains to be further elucidated. MicroRNAs have been reported to be key regulators of osteoblast differentiation and proliferation. Here, we found that miR-144-3p is down-regulated during osteoblast differentiation of C3H10T1/2 cells. Overexpression of miR-144-3p inhibited osteogenic differentiation, whereas inhibition of miR-144-3p reversed this process. Furthermore, miR-144-3p inhibited the proliferation of C3H10T1/2 cells by arresting cells at the G0/G1 phase. Results from bioinformatics analysis, luciferase assay and western blotting demonstrated that miR-144-3p directly targeted Smad4. Additionally, Smad4 knockdown blocks the effects of miR-144-3p inhibitor. Therefore, we conclude that miR-144-3p negatively regulates osteogenic differentiation and proliferation of C3H10T1/2 cells by targeting Smad4.