Fig. 5: The type of ecological interaction alters regrowth time after radiation.
a–d For each type of ecological interaction (i.e., antagonism, competition, and mutualism), mixed spheroids were grown in silico using a range of interaction parameters λP and λRR until the volume reached 0.9 mm3. At this volume, spheroids were irradiated (6 Gy) in silico and monitored for regrowth until they reached 0.9 mm3. Radiation damage was simulated using the linear-quadratic model, for which input values (α and β) were determined from experimental PC3 clonogenic assays: parental population, α = 0.44 ± 0.07 and β = 0.04 ± 0.01; radioresistant population, α = 0.35 ± 0.06 and β = 0.03 ± 0.01. The numbers of parental and radioresistant cells at the time of radiation depend on the values of λP and λRR, whereas the numbers post-radiation depend on the effect of radiation on each population, and on the values of λP and λRR. See Supplementary Methods section 1 for more details on the mathematical model.
