Figure 12. Effect of Robo4 on the cell cycles of RF/6A and human RPE cells. A: Cell cycle of NS siRNA-treated RPE cells. B: Cell cycle of Robo4 siRNA-treated RPE cells. C: Cell cycle of NS siRNA-treated RF/6A cells. D: Cell cycle of Robo4 siRNA-treated RF/6A cells. E: The data of RPE cell cycle distribution of NS and Robo4 siRNA group cells. F: was the data of RF/6A cell cycle distribution of NS and Robo4 siRNA group cells. Flow cytometric analysis demonstrated the effects of Robo4 on the cell cycle. The x-axis represents the fluorescence intensity on a logarithmic scale and the y-axis represents the number of events. The results show that the fraction of G1-phase cells increased and the proportion of S-phase cells decreased in the RF/6A and RPE cells after knockdown of Robo4. Values are the means±SD of at least three independent experiments. The proportion of G0/G1, G2, and S phase cells was decreased in Robo4 siRNA-treated RPE cells compared to NS siRNA-treated RPE cells (E, *p<0.01). The proportion of G0/G1 and S phase cells was decreased in Robo4 siRNA-treated RF/6A cells compared to NS siRNA-treated RF/6A cells (F, *p<0.01). Abbreviations: control siRNA-treated cells (NS); Robo4 siRNA-treated cells (R4 siRNA). The cell cycle of NS was set to 100%.