Competition between two cell types under cell cycle regulation with apoptosis*

Competition between different cell or tissue types is critical in fields as diverse as bacterial ecology, developmental biology, and tumor growth. We have recently developed a mechanical model that incorporates cell cycle regulation [Li J. et al. PRX (2021)]. This model involves a characteristic pressure at which the cells become quiescent over time. Here we report on extensions of this model to multiple cell types. We study how the combination of characteristic pressure and apoptosis rate impact the competition process. Using an analytical model and discrete simulation, we explore how cells coexist/outcompete each other under two initial conditions: a nearly planar interface between two cell types and one in which a small nucleus of one cells type is surrounded by the other.

We determine the coexistence line on which two colonies coexist. We find that not always does the colony with the higher characteristic pressure invade the other, but the apoptosis rate can also play a key role. Comparing the dynamics from the two initial conditions reveals the role of statistical noise and Laplace pressure. Our findings shed light on how cancer develops and draw attention to the interplay between characteristic pressure and apoptosis rate.