Effects of miR-93 antisense oligonucleotides on cell proliferation and apoptosis in breast cancer

Abstract:

Objective：To investigate the expression of miR-93 in breast cancer tissues and to explore the regulative effects of miR-93 antisense oligonucleotide（ASO） on the proliferation and apoptosis of breast cancer cells. Methods：Expression of miR-93 in 120 breast cancer tissues and their adjacent tissues was detected by real-time quantitative PCR. After transfection with miR-93 ASO，biological effects of miR-93 on breast cancer cells were measured by MTT assay，colony formation experiment and flow cytometry. Results：Expression of miR-93 was higher in 63.33%（76/120） breast cancer tissues than in adjacent tissues（P<0.05）. miR-93 ASO could reduce the expression of miR-93 significantly（P<0.05）. MTT assay results showed that breast cancer cells survival rate at 24，48，96 h decreased greatly after transfection with miR-93 ASO（P<0.05）. Clone formation assay revealed that colony formation rate was significantly lower in miR-93 ASO group than in blank control group and nonsense interference group（P<0.05）. Flow cytometry indicated that the apoptotic index was significantly higher in miR-93 ASO group than in two control groups（P<0.05）. In addition，Bcl2 mRNA and protein levels were significantly decreased after reducing expression of miR-93. Conclusions：miR-93 is overex－pressed in the human breast cancer. Reducing expression of miR-93 can effectively inhibit the growth of breast cancer cells and pro－mote apoptosis . miR-93 may become a new target for the regulation of gene expression in breast cancer.