Perturbation of MT growth or shortening affects cell branching and migration similarly in 2D and 3D ECMs. (A) Immunolocalization of MTs and fluorescent phalloidin staining of actin in HUVECs cultured in 8.7 kPa or 0.7 kPa compliant 3D ECMs and treated for 90 min with DMSO vehicle (control), 20 µM nocodazole (Noc.), or 20 µM taxol. Bars, 20 µm. (B) Analysis of the effects of the treatments in A on cell branch frequency and length compared with similar drug treatments of cells plated on 2D 8.7 kPa ECMs. (C) Analysis of the effects of the treatments in A on cell migration velocity and distance to origin compared with similar drug treatments of cells cultured on 2D 8.7 kPa ECMs. *, P < 0.05 comparing compliance versus compliance + drug. **, P < 0.05 compared with 2D 8.7 kPa ECMs (one-way ANOVA). Error bars indicate standard deviation.