Effect of VPO1 knockdown on Ang II-induced proliferation of A10 VSMCs. (A and B) VPO1-shRNA successfully decreased VPO1 mRNA and protein expression, respectively. **P < 0.01 vs. control (C-shRNA). (C) BrDU incorporation. (D) Cell cycle analysis by flow cytometry. Control, wild-type cells; Ang II, wild-type cells treated with 100 nmol/L Ang II for 24 h; VPO1-shRNA, cells transfected with VPO1-shRNA; VPO1-shRNA + Ang II, VPO1-shRNA-tranfected cells treated with 100 nmol/L Ang II for 24 h. **P < 0.01 vs. control; ++P< 0.01 vs. Ang II. n = 3. Data are representative of three independent experiments.