miR-140-3p exhibits repressive functions on preosteoblast viability and differentiation by downregulating MCF2L in osteoporosis.

Previous research manifested that miR-140-3p was a latent biomarker for osteoporosis. Nevertheless, the mechanism of miR-140-3p in osteoporosis is still not clear and needs ulteriorly studying. The purpose of our paper was to ulteriorly probe the underlying mechanism of miR-140-3p on osteoporosis. Firstly, based on the data acquired from GEO database, we found that miR-140-3p was highly expressed; meanwhile, MCF2L was lowly expressed in osteoporosis patients. Upregulation/downregulation of miR-140-3p by miR-140-3p mimic/inhibitor restrained/promoted MC3T3-E1 cell viability and differentiation. However, miR-140-3p over-expression/downregulation accelerated/repressed MC3T3-E1 cell apoptosis. MCF2L was forecasted as a target of miR-140-3p by miRanda, miRWalk, and TargetScan miRNA target gene prediction software. Luciferase reporter assay confirmed that MCF2L could be directly targeted by miR-140-3p. Moreover, we identified that the expression of MCF2L was negatively regulated by miR-140-3p. From rescue assays, we discovered that knockdown of MCF2L weakened the promoting influence of miR-140-3p ablation on MC3T3-E1 cell viability and differentiation, and receded the suppressing impact of miR-140-3p reduction on MC3T3-E1 cell apoptosis. Above all, this research disclosed that miR-140-3p repressed preosteoblast viability and differentiation while promoted preosteoblast apoptosis via targeting MCF2L. Our discoveries might afford a theoretical basis of developing a latent novel target for osteoporosis therapy.