Decreased miR-127 promotes the occurrence of breast cancer via increasing the expression of SPP1

Background. The expression of miR-127 has been reported to be decreased in the breast tissue of patients with breast cancer (BRC). However, the mechanism of miR-127 involvement in the pathogenesis of BRC is still unclear and requires urgent clarification. Objectives. To explore the role of miR-127 in the pathogenesis of BRC. Materials and methods. In this study, we measured the expression of miR-127 in blood samples of 60 BRC patients and 60 controls, investigated the influence of miR-127 on the viability and apoptosis of MCF-7 and MDA-231 cells, identified a miR-127 target gene, and determined the expression level of the target gene in the blood samples of BRC patients and controls. Results. We found that miR-127 expression was significantly decreased in the plasma of BRC patients compared to controls. Additionally, the upregulation of miR-127 in MCF-7 and MDA-231 cells inhibited their proliferation and promoted their apoptosis. Conversely, the downregulation of miR-127 promoted cell proliferation and inhibited their apoptosis. The SPP1 was successively predicted and validated as a target gene of miR-127. Finally, the expression level of SPP1 was significantly increased in the plasma of BRC patients compared to controls. Conclusions. Our study demonstrated that decreased miR-127 may promote BRC cell proliferation, inhibit apoptosis and promote the occurrence of BRC through increasing the SPP1 expression level.