Soft topographical patterns trigger a stiffness-dependent cellular response to contact guidance

Directional migration is involved in multiple physiological and pathological processes. Among other external signals, the architecture of the extracellular matrix can trigger directed cell migration through a phenomenon known as contact guidance: cells elongate, align, and migrate along the direction set by aligned extracellular matrix fibers. This process involves the orientation of focal adhesions, actin, and tubulin cytoskeleton along the direction of those fibers. Contact guidance has been extensively studied on stiff materials with topographical grooved patterns. However, how it translates to softer physiologically relevant compliances is not known. Here we show that substrate stiffness modulates the cellular response to topographical contact guidance. We found that for fibroblasts, while focal adhesions and actin responded to topography independently of the stiffness, microtubules showed a stiffness-dependent response that regulates contact guidance. On the other hand, both clusters and single breast carcinoma epithelial cells displayed stiffness-dependent contact guidance migration, leading to more directional and efficient migration when increasing substrate stiffness. These results suggest that both matrix stiffening and alignment of extracellular matrix fibers cooperate during directional cell migration, and both should be accounted when studying processes such as cancer cell invasion. Teaser Changes in the stiffness of topographical patterns modify how mesenchymal and epithelial cells perform contact guidance.