Fig. 2

Pre-miR-183 exhibits tumor-suppressive phenotypes in TNBC cell lines. a-b Effect of pre-miR-183 overexpression on cell invasion and migration. pre-miR-183 overexpression was induced with doxycycline for 72 h in MDA-MB-231 and BT-549 cells. Cells were starved with 0% FBS medium for 24 h, seeded in starvation medium into transwell inserts (a) with or (b) without matrigel and were then allowed to invade towards 10% FBS as chemoattractant for 16 h. The cells on the lower side of the membrane were imaged and quantified with Molecular Devices Microscope IXM XLS. The number of migrated or invaded cells was normalized to the seeding control. Invaded cells were counterstained with crystal violet for visualization. Statistical analysis: ordinary one-way ANOVA followed by Tukey’s multiple comparisons test. c-d Effect of 5’isomiR-183-5p overexpression on cell migration and invasion. MDA-MB-231 and BT-549 cells were transfected with miRNA mimics or miRNA negative control for 48 h and then starved with 0% FBS medium for 24 h. The starved cells were reseeded in starvation medium into transwell inserts (c) with or (d) without matrigel and allowed to migrate or invade upon 10% FBS as chemoattractant for 16 h. The cells on the lower side of the membrane were imaged and quantified with Molecular Devices Microscope IXM XLS. The number of migrated or invaded cells was normalized to the seeding control. Values are depicted relative to the miRNA negative control. Data are presented as mean ± SD, n = 3 (each derived from the median of 3 technical replicates). Statistical analysis: ordinary one-way ANOVA followed by Dunnett’s multiple comparisons test *p < 0.05, **p < 0.01, ***p < 0.001 compared to control