The actin cytoskeleton is substantially modified in cancer cells because of changes in actin-binding protein
abundance and functional activity. As a consequence, cancer cells have distinctive motility and mechanical
properties, which are important for many processes, including invasion and metastasis. Here, we studied the
effects of actin cytoskeleton alterations induced by specific nucleation inhibitors (SMIFH2, CK-666), cytochalasin
D, Y-27632 and detachment fromthe surface by trypsinization on themechanical properties of normal Vero and
prostate cancer cell line DU145. The Young's modulus of Vero cells was 1300 ± 900 Pa, while the prostate
cancer cell line DU145 exhibited significantly lower Young's moduli (600 ± 400 Pa). The Young's moduli
exhibited a log-normal distribution for both cell lines. Unlike normal cells, cancer cells demonstrated diverse
viscoelastic behavior and different responses to actin cytoskeleton reorganization. They were more resistant to
specific formin-dependent nucleation inhibition, and reinforced their cortical actin after detachment from the
substrate. This article is part of a Special Issue entitled: Mechanobiology.