Figure 6

Effect of Slug and miR-221 knockdown on MDA-MB-231 cell migration ability. (A) Cells were transfected with 30nM si-Slug, a non-relevant siRNA (si-Scr), antagomiR-221 or a non-relevant antagomiR (antagomiR-Scr). Twenty-four hours after transfection, cells monolayer were scratch wounded with a 20-μl pipet tip (0 h), and observed over the indicated time periods, 0 and 24 hours (4x magnification). Scale bar =100 μm. (B) Proliferation curves of MDA-MB-231 cells exposed to si-Slug, si-Scr, antagomiR-221 and antagomiR-Scr up to six days. Statistical analysis was performed si-Slug or antagomiR-221 treated cells versus untreated cells (Ctr) (*), and si-Slug or antagomiR-221 treated cells versus si-Scr or antagomiR-Scr respectively (o); p ≤ 0.05. (C) Slug and miR-221 RNA levels were analysed by quantitative RT-PCR after antagomiR-221 or antagomiR-Scr treatment, and results were calculated using the ΔΔCt method. Data are presented as fold difference respect to control untreated cells (Ctr). Results represent means ± SEM of three independent experiments. p-values ≤ 0.05 were considered statistically significant. The expression of Slug, E-cadherin, ERα proteins was also analyzed by Western Blot. IP3K was used as loading control.