Vector field simulations of TACS and neovessel invasion.

Microvessels were simulated to originate in a tumor periphery (inset, orange). Microvessels grow towards the tumor (inset, magenta) but must cross a tissue interface (inset, yellow). Alignment and density of the interface is varied to mimic various tumor associated collagen signatures (TACS). The interface structure contained either an isotropic fibril ODF (circle) or aligned ODFs (ellipses) running either perpendicular to the tumor or towards the tumor. The interface density was either 3 mg/mL or 5 mg/mL. Representative Z projections of the interface and tumor region are presented at the bottom. High interface density generally reduced the length of microvessels that crossed into the tumor. Fibril alignment towards the tumor facilitated crossing while alignment perpendicular to the tumor deflected vessels or trapped them within the interface. Unlike the EFD simulations, fibril alignment towards the tumor did not nullify the effects of increased matrix density for TACS-1+3. ***: p (TIF)