  The rheological properties of brushes of different length on the surface of
human epithelial cancerous cells are studied here by means of coarse grained
numerical simulations, where the surface of the cell is subjected to an
external oscillatory force acting on the plane of the cell surface. We model
explicitly the tip of an atomic force microscope and the cancerous cell as a
surface covered by brushes of different length, and take into account the
interactions of the brush chains with the tip and with each other, leading to
complex rheological behavior as displayed by the profiles of viscosity and the
friction coefficient of this complex system. We comment briefly on how these
findings can help in the experimental effort to understand the nature of the
cancer growth in human epithelial cells.
