Fig. 4

Restoration of miR-7 inhibits GC cell viability and invasiveness in vitro. HGC-27 and MKN-28 cells were stably transfected with mature miR-7 or negative control, respectively. a and b Restoration of miR-7 expression decreased Cell viability and inhibited Ki67 expression in GC cells. Cell viability (a) was determined by CCK-8 assay at absorbance 450 nm for 5 consecutive days. Ki67 protein expression in indicated cells (b) were measured by Flow cytometry using specific Ki67 antibodies. Representative images are shown. c Restoration of miR-7 expression suppressed Colony formation in GC cells. Colony formation assay was performed to examine colony formation ability in indicated cells. Colony numbers were counted for 3 weeks after transfection. Representative images of colonies formed are shown. Bar, 100 μm. d and e miR-7 expression promoted significant G0/G1 phase arrest but not cell apoptosis. Cell cycle were measured by flow cytometry analysis after PI staining in indicated cells (d). Cell apoptosis were detected by FACS analysis using Annexin V-PE/7-AAD double staining (e). Representative images of colonies formed and FACS analysis are shown. Data are presented as mean ± SD of three independent experiments. f and g Restoration of miR-7 inhibited GC cell migration and invasion. Cell migration assay (f) and cell invasion assay (g) were performed in 24-well non-coated or Matrigel-coated Transwell Chambers (8-μm pore size). Cell numbers were counted in 5–10 random fields. Data are presented as mean ± SD of three independent experiments. Representative images are shown. ** p < 0.01 and *** p < 0.001 between the indicated two groups determined by paired student’s t test