Figure 3

Knockdown of CK2α inhibited cell proliferation and promoted cell senescence of CRC cell lines. (A) Western blot analysis of CK2α protein in lysates of cells transfected with a specific CK2α siRNA or treated with emodin. GAPDH expression was used as a loading control. (B) MTT assay of the proliferating cells transfected with a CK2α-specific siRNA or a nonspecific siRNA and treated with emodin. Points, mean of three independent experiments; bars, SD. *P < 0.01 versus LoVo/Mock; #P < 0.01 versus SW480/Mock; †P < 0.01 versus LoVo/DMSO; ‡P < 0.01 versus SW480/DMSO. (C) The number of colonies formed from cells transfected with CK2α siRNA. Colonies were stained with crystal violet and counted. Columns, mean of three independent experiments; bars, SD. ++P < 0.01. (D) The number of SA-β-gal-positive cells (green) 48 h after transfection with CK2α siRNA. Cells were stained with SA-β-gal staining solution. Columns, mean of three independent experiments; bars, SD. ‡‡P < 0.01.