Figure 4

ECM microtopography retards motility of less tumorigenic colon cancer cells via Rho A. Microtopography has a significant inhibitory impact on the motility of the less tumorigenic Caco-2 E cells as can be seen by the decrease in both the cellular velocity and the movement coefficients when plated on either a pit or a post microtopography (panel A and panel C, p < 0.01). The overall result is a decrease in the total distance traveled by the Caco-2 E cells when plated on either a pit or a post microtopography (panel A). When Caco-2 E cells transfected with Rho A siRNA are plated on pit microtopography--which emulates the native environment of less tumorigenic cells--there is an increase in cell motility suggesting that Rho A plays an integral role in regulating cell motility in less tumorigenic cells (panels B and C). Panel D is a representative western blot showing successful knockdown of Rho A. The x and y axes in panels A and B are in μm and the colored lines are representative cell trajectories. The values in panel C are the mean ± the standard error. Where: * = p < 0.01, ** = p < 0.05 when comparing the standard and transfected values.