FIGURE 2.

In silico testing of requirements for tumor maintenance. A, Amount of tumor cells (blue) and percentage of stem cells (orange, dotted) simulated over time under the condition that included only stem cells to maintain tumors. Simulations for six different initial percentages of stem cells (SCstart) are shown. B, Similar plot testing the condition in which the proliferative advantage of mutated tumor cells is the only source for tumor maintenance. Simulations for three different probabilities of acquiring mutations (Pmut) are shown. C, Similar plot testing the condition in which tumor maintenance depends on both stem cells and tumor cells that can gain mutations. Four combinations of initial stem cell percentage and probability of mutation acquisition are shown.