RESUMEN
<p><b>OBJECTIVE</b>To investigate the effect and mechanism of miR-15a on the induction of apoptosis in breast cancer cells.</p><p><b>METHODS</b>To detect the expression level of miR-15a in breast cancer cell line MCF-7 cells and human mammary gland epithelial cell line MCF-10A cells by quantitative PCR. The target point of MCF-7 was predicted by software and was validated by luciferase report gene system. MiR-15a was transfected into MCF-7 cells with liposomes. The expression of Bcl-2 in MCF-7 cells was detected by Western blotting and the apoptosis rate of MCF-7 cells was detected by flow cytometry.</p><p><b>RESULTS</b>The expression level of miR-15a in MCF-7 cells was lower than that in the MCF-10A cells (0.253:1, P < 0.0001). The expression of MiR-15a was significantly inhibited by Bcl-2 (P < 0.05). Compared with the control, Bcl-2 expression was significantly decreased in the MCF-7 cells. The results of flow cytometry showed that the apoptosis rate was 13.4% in non-transfected MCF-7 cells, 15.9% in MCF-7 cells transfected with control RNA, and 31.5% in MCF-7 cells transfected with miR-15a (P < 0.05), indicating an evident induction of apoptosis in the MCF-7 cells.</p><p><b>CONCLUSION</b>miR-15a may have a potential application value in breast carcinoma biotherapy.</p>