LNA-antimiR-21 suppressed BC cell growth, proliferation and migration in vitro. (a) miR-21 expression levels (normalized to U6 RNA) were significantly depressed by 98% (P < 0.01) in MCF-7/LNA-antimiR-21 and 77% (P < 0.01) in MDA/LNA-antimiR-21 cells, relative to the LNA-control. The graph shows RQ calculated by normalizing the miR-21 expression values in LNA-antimiR-21 treated cells on those in the LNA-control treated cells. (b) MTT assay showed that MCF-7/antimiR-21 and MDA-MB-231/antimiR-21 cells grew slower than cells transfected with the LNA-control. (c) Representative wells showing total numbers of colonies formed by LNA-antimiR-treated cells standardized against control cells (set to 100%). (d) Representative image of in vitro wound healing assay of MCF-7 and MDA-MB-231 at 0, 24 and 48 h after wound scratch. Data are mean + SD, n = 3. * P < 0.05, ** P < 0.01.