Fig. 5. Down-regulation of EGR1 promotes ESCC cell proliferation and invasion. (A) Western blot analysis of EGR1 expression in EC9706 cells transfected with EGR1 siRNA or corresponding control. β-actin was used as an internal control. (B) MTT assay of EC9706 cells transfected with EGR1 siRNA or control. (C) The colony formation assays in EC9706 transfected with EGR1 siRNA or control. Colonies were evaluated and values were reported as the ratio. (D) The BrdU assays from EC9706 transfected with EGR1 siRNA or control. (E) Transwell assays of EC9706 cells transfected with EGR1 siRNA or control. Left panel: representative images. Right panel: quantification of 10 randomly selected fields. ^*p<0.05, ^**p<0.01, ^***p<0.001. EGR1, early growth response 1; ESCC, esophageal squamous cell carcinoma; MTT, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide; OD, optical density.