RNAi knockdown of PIK3CA preferentially inhibits invasion of mutant PIK3CA cells

Figure 1 Expression analyses of PIK3CA mRNA determined by quantitative real time polymerase chain reaction at 24 h post-transfection. Values are shown as mean ± SD. Exp: Experimental group; Neg: Negative control group; Con: Control group. ^aP < 0.05 vs controls, n = 3.

Figure 2 Protein expression of PIK3CA and p-Akt in gastric cancer cells. A: Expression analyses of PIK3CA and p-Akt protein in cells by Western blotting assay. The representative data are shown in triplicate experiments. β-actin: internal control protein; B and C: Statistical evaluation of relative expression of PIK3CA and p-Akt protein quantified by grey analyses with SigmaPlot 8.0 software. Exp: Experimental group; Neg: Negative control group; Con: Control group. ^aP < 0.05 vs controls, n = 3.

Figure 3 Cell proliferation assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Values are mean ± SD. Con: Control group; Neg: Negative control group; Exp: Experimental group. ^bP < 0.01 vs controls, n = 3.

Figure 4 PIK3CA-siRNA reduced migration of BGC-823 and HGC-27 cells using an in vitro wound healing assay. A: The results were expressed as average gap and compared with the two control groups. The distance of the wound was measured at five reference points along the scratch wound. ^aP < 0.05 vs controls, ^bP < 0.01 vs controls, n = 3; B: A representative result of cell migration at 0 h and 24 h (original magnification, × 150). Con: Control group; Neg: Negative control group; Exp: Experimental group.

Figure 5 Effect of PIK3CA silencing on tumor cell invasion. A: PIK3CA knockdown reduces invasion ability of gastric cancer cells; B: A representative result of cell invasiveness among the three groups of cells (original magnification of BGC-823 and HGC-27 cells, × 200, × 150, respectively). Con: Control group; Neg: Negative control group; Exp: Experimental group. ^bP < 0.01 vs controls, n = 3.