Data from: Modeling tumor transport and growth with poroelastic biopolymer networks

The mechanical properties of the extracellular matrix (ECM) regulate tumor
growth and invasion in the tumor microenvironment. Models of biopolymer
networks have been used to investigate the impact of the elasticity and
viscoelasticity of ECM on tumor behavior. Under tumor compression, these
networks also show poroelastic behavior that is governed by the resistance
to water flow through their pores. This work investigates the hypothesis
that stress-dependent transport properties of biopolymer networks regulate
tumor growth. Here, alginate hydrogels are used as a model ECM system with
tunable ionic and hybrid ionic/covalent crosslinking. Hydrogel stiffness,
viscoelasticity, and stress relaxation behavior were characterized using
stepwise axial compression. Among these properties, we find that
poroelastic fluid outflow dominates ECM stress relaxation, as the measured
water flux was significantly affected under compression. Continuum
mechanics-based modeling was developed to formulate and calculate the
chemical potential gradients of water (solvent) in the hydrogels under
compression. This framework was extended into an advection-diffusion
framework to quantify growth factor (solute) distribution under varying
strengths of stress and diffusion indexed by the relative strength of
convective to diffusive transport, characterized by the Péclet number. An
agent-based computational simulation showed that the Péclet numbers based
on our experimental timescales strongly influenced tumor growth over
longer, more physiologic timescales. Together, these results highlight the
important role of water flux and transport in three-dimensional biopolymer
networks.