Figure 5

Inhibition of ROCK-II expression by ROCK-II siRNA abolished formononetin-induced stress fiber formation and cell migration in HUVECs.

HUVECs transfected with non-specific siRNA were treated with (A,a) 0.1% DMSO or (B,b) 50 μM formononetin for 8 h to serve as negative and positive control, respectively. Cell nuclei were labeled with Hochest 33342 and F-actin was labeled with TRITC-phalloidin. Yellow arrowhead indicated stress fibers terminated at pointed edges. ROCK-II expression was inhibited in HUVECs by using ROCK-II siRNA and the cells were treated with (C,c) 0.1% DMSO or (D,d) 50 μM formononetin for 8 h. White asterisk indicated cortical actin complexes formed in HUVECs transfected with ROCK-II siRNA. White and yellow scale bars represent 50 μm and 20 μm respectively. (E) Real-time cell migration of HUVECs transfected with ROCK-II siRNA with or without formononetin treatments as detected by the xCELLigence system. HUVECs were transfected with ROCK-II siRNA for 2 days, followed by 0.1% DMSO or 50 μM formononetin for 24 h. (F) Statistical analysis of cell migration index of xCELLigence system following formononetin treatment for 20 h. Values are presented as the increment of migration ± SD (n = 3), for three independent experiments. **p < 0.01 vs. control.