Fig. 5

Distribution of molecules. Distribution of oxygen (blue) and VEGF molecules (green) as a function of the distance from the center of the tumor (x = 0) at different time steps throughout the simulation (left column followed by right column, from top to bottom). Oxygen is initially present everywhere but is gradually consumed by the tumor and in parallel secreted by vessels. VEGF is secreted by the tumor and spreads out while being consumed by the endothelial cells. The VEGF in the first two graphs is due to secretion by fibroblasts and not by the tumor