Figure 5. Effect of FAM18B knockdown on human retinal microvascular endothelial cell tube formation. A: Representative images of tube formation in various treatment groups. (i) Scrambled control; (ii) scrambled control treated with vascular endothelial growth factor (VEGF); and (iii) scrambled control treated with pyrrolidine dithiocarbamate (PDTC). (iv) FAM18B siRNA-treated cells; (v) FAM18B siRNA treated with VEGF; and (vi) FAM18B siRNA treated with PDTC. B: The tube formation of human retinal microvascular endothelial cells (HRMECs) in transfected with scrambled control siRNA or FAM18B transfected siRNA treated with or without PDTC. FAM18B knockdown increases the basal tube formation of HRMECs. The enhanced basal tube formation is inhibited by PDTC, a specific nuclear factor-kappa B (NF-κB) inhibitor. C: Tube formation in control siRNA-transfected cells and FAM18B siRNA-transfected cells treated with or without VEGF. VEGF increases tube formation of control cells but not in FAM18B siRNA transfected cells. The data are represented as mean±standard deviation (SD) (n=3). * p value <0.05 compared to control cells treated with media alone. † p value <0.05 compared to FAM18B siRNA-transfected cells.