Abstract
Most tumors originate from epithelia, which are under constant cell renewal. In multilayered epithelia, the interface between the epithelium and the connective tissue often presents different degrees of undulation, which are typically more pronounced in pre-malignant and malignant tissues. We propose that part of these undulations originate from a mechanical instability due to a differential cell flow in the epithelium. The instability is favored by known characteristics of cancerous tissues and is enhanced by diffusion inhomogeneities of metabolites via a mechanism reminiscent of the classical Mullins-Sekerka instability in the context of crystal growth. Such undulations may also be present at steady state if stochastic processes underlie the epithelium dynamics. We characterize the surface undulations of the epithelium in the presence of stochastic cell-renewal and force-generation processes. The obtained fluctuation spectrum encompasses the case of a viscous fluid at thermodynamic equilibrium when active processes are turned off. For a living tissue, detailed balance is broken. A generalized fluctuation-response relation is however recovered in the limit of long timescales compared with the relaxation times of active processes.
To learn more about the speaker, please visit his university’s webpage.