Figure 5.

IL-17A acts through MTA1 to promote invasion of human cancer cells. HeLa and DU-145 cells were transfected with either control siRNA or siRNA targeting MTA1. Invasion assays were performed using Matrigel®-coated invasion chambers. Approximately 2 x10⁵ cells were seeded in each upper chamber in serum-free medium without or with 20 ng/ml recombinant human IL-17A in triplicate wells per group, while the lower chamber contained medium with 10% FBS. After 24 h, non-invading cells were removed from the upper chamber; the cells invaded through the Matrigel®-coated porous membrane were fixed with methanol, stained with 0.5% crystal violet, and counted under a microscope. (A) Western blot analyses of MTA1 expression in HeLa and DU-145 cells transfected with control siRNA and MTA1 siRNA, with 20 ng/ml recombinant human IL-17A treatment for the indicated time. (B,D) Representative photomicrographs of the porous membrane with stained cells; for HeLa cells, one picture per well under 100 × magnification (scale bar, 400 μm) was taken, which covered almost the entire porous membrane, and the inserted frame showed the stained cells under 200 × magnification; for DU-145 cells, one representative of 5 regions taken under 200 × magnification (scale bar, 200 μm) was shown. (C,E) Number of the cells invaded through the porous membrane; data represent mean ± standard deviation (SD, error bars) of 3 independent experiments; a, p < 0.01 between the control siRNA + IL-17A group and the control siRNA group; b, p < 0.01 between the MTA1 siRNA + IL-17A group and the control siRNA + IL-17A group; there was no significant difference between the MTA1 siRNA + IL-17A group and the MTA1 siRNA group (p > 0.05).