Figure 3

MiR-20b inhibits PTEN protein expression. (A-B) MiR-20b expression was detected by qRT-PCR. ZR-75-30 and MCF-7 breast cancer cells transfected with miR-20b mimics showed a significant increase in miR-20b expression (A), while the cells transfected with miR-20b inhibitor resulted in a significant decrease of miR-20b expression (B). (C-D) qRT-PCR analysis of PTEN mRNA expression. ZR-75-30 and MCF-7 breast cancer cells transfected with miR-20b mimics or inhibitor did not affect PTEN mRNA expression. (E) Representative pictures of PTEN protein expression detected by western blot. (F) Quantitative analysis showed that PTEN protein expression in breast cancer cells transfected with miR-20b mimics decreased when compared with the negative control. Error bars represent mean ± SD from three independent experiments. *, P < 0.05; ***, P < 0.001. NS, no significant differences.