Figure 1.

Procedures for quantifying durotactic migration by a population of single human cancer cells. (A) A polyacrylamide stiffness gradient to which fibronectin is covalently attached to provide an adhesive substrate is seeded with a population of cells at a sufficiently low density to allow (B) imaging of individual migrating cells using phase-contrast or fluorescence time-lapse microscopy for (C) computer-based analysis of migratory track using FastTracks software (42). (D) Graphical schematic of a cell trajectory (red dashed line) and variables used to characterize migratory phenotypes. The equations used to calculate cell migration parameters are listed on the right. To see this figure in color, go online.