Fig. 2: Overexpression of miR-133b suppresses colonigenic ability and metastasis-relevant traits of breast cancer cell lines in vitro.

a MiR-133b overexpression suppresses proliferation of MDA-MB-231 and BT549 cells. MDA-MB-231 and BT549 cells transfected with 100 nM miR-133b and NC mimics respectively were seeded in six-well plates. Total cell number and cell viability were assessed by Vi-Cell XR Cell Viability Analyzer every 2 days after transfection. b Influence of miR-133b on colony formation of MDA-MB-231 and BT549 cells. In all, 300 cells were seeded in six-well plates for 12 days to form visible colonies. Representative images are presented (left panel). The number of clones formed was quantified and shown in the right panel. c Wound-healing assay of MDA-MB-231 and BT549 cells transfected with NC or miR-133b mimics in each condition were shown. A scratch wound was made and images from five different fields were taken. Representative pictures of one field at the beginning (t = 0 h) and at the end of the recording (t = 12 h) were shown (left panel). Cell migration was quantitated as percentage of would-healed area (right panel). d, e Migration and Invasion assays of MDA-MB-231 and BT549 cells transfected with 100 nM NC or miR-133b mimics. Cell migration d and invasion e of above cells were quantitatively analyzed 18 h after seeding in Transwells. Data are presented as mean ± S.D. The symbol * denotes statistical difference (p < 0.05), whereas ** and *** represent great significant difference (p < 0.01 and p < 0.001) by a two-tailed Student’s t-test