Fig 7. Cell spreading area and circularity of MDA-MB-231 cells as a function of adaptation to substrate stiffness, where cells were seeded onto the PA substrates for 9 consecutive days without re-passaging.

(A) Representative phase contrast images of MDA-MB-231 cells on TCP and 1 kPa PA gels. Scale bar is 100 μm. (B) Cell spreading area and (C) circularity of MDA-MB-231 cells on TCP and 1 kPa PA gels as a function of culture time.