Solid tumors are poroelastic solids with a chemo-mechanical feedback on growth

Area of Science:

• Biophysics
• Mechanobiology
• Tumor Microenvironment

Background:

• Tumor growth involves complex interactions between cellular mechanics and proliferation.
• The rheological properties and growth laws governing solid tumors remain poorly understood.
• Experimental evidence suggests a feedback loop between mechanical stress and tumor growth.

Purpose of the Study:

• To theoretically analyze the mechanical properties and growth laws of tumor spheroids.
• To investigate the feedback mechanism between mechanical stress and cell proliferation in tumors.
• To explain the observed volumetric growth profiles and residual stress patterns in solid tumors.

Main Methods:

• Theoretical analysis of in vitro and in vivo tumor spheroid growth experiments.
• Modeling tumor spheroids as poroelastic materials with an elastic solid cellular component.
• Utilizing a novel numerical approach to correlate residual stress with tumor opening angles.

Main Results:

• Solid tumors exhibit poroelastic characteristics with the cellular component acting as an elastic solid.
• Tumor growth volume asymptomatically depends on applied boundary compression.
• A peculiar tensional pattern and residual stress are observed in solid tumors, quantifiable via opening angle.
• Mechanisms involve feedback of mechanics on proliferation, modulated by nutrient availability and diffusion-consumption balance.

Conclusions:

• Tumor growth is governed by a feedback loop between mechanical stress and proliferation, influenced by nutrient gradients.
• The poroelastic model and numerical analysis accurately reproduce tumor volumetric growth and residual stress patterns.
• Understanding these mechanobiological feedback mechanisms is crucial for cancer research and therapy development.