Probing the biophysical properties of tumor cells during mitosis by atomic force microscopy

Mitosis is an important physiological event accompanying with dramatic changes of cellar biophysical properties. Failure of mitosis results in cell death or chromosome aneuploidy. In this study, we used atomic force microscopy to probe and compare the biophysical properties of tumor cells at different stages during mitosis. The rounding forces of MCF-7 cells oscillated during mitosis. At anaphase, the average elasticity of cells was higher than that at other phases. Cholesterol depletion with M(upbeta )CD led to an increase in the average elasticity, whereas the average roughness of membrane surface decreased at the absence of cholesterol. Our study indicated that the distribution of actin filaments could affect the biophysical properties of tumor cells and cellular morphology during mitosis. Furthermore, the biophysical properties of tumor cells were also regulated by membrane cholesterol during mitosis. This work provides a new detection approach for monitoring tumor cell development at single cell level.