Figure 6. PI3K and AKT are necessary for ARF6-GTP-dependent melanoma invasion.
(a,c) Matrigel invasion of A2058 cells is increased by ectopic expression of Myc-tagged ARF6Q67L (a-d). (a) The AKT inhibitor MK2206 (1μM) or (c) the PI3K inhibitor GDC0941 (1μM) eliminates ARF6Q67L-induced invasion. Error bars = S.D., ****p<0.0001, ANOVA with Tukey’s multiple comparisons test. (b, d) MYC-tagged ARF6Q67L expression relative to endogenous ARF6. (e) pAKT levels and localization in invading A2058 cells, plated on Matrigel dome, serum starved in PBS. Top row = 20 hours after plating, 600x magnification, scale bars = 60μM. Middle and bottom rows = 48 hours after plating, 1200x magnification, scale bars = 30μm. (f) ARF6Q67L–induced pAKT and cortactin colocalization in A2058 cells invading and degrading gelatin (labeled with Oregon Green 488).