Figure 5
TP53 and ABCB1 modulated drug response can be modelled in 3D spheroids. (a) ONS76 (blue) and ONS76 dnp53 (red) cell lines were treated with increasing concentrations of vincristine in both 2D monolayer (i) and 3D spheroid (ii) culture. The CellTiter-Glo 3D cell viability assay was performed to compare responses and viability was calculated as a percentage of the vehicle-treated controls. There was a significant difference in drug response between the cell lines in 3D, but not 2D, culture. Dose response curves were generated using non-linear regression analyses and error bars represent the mean ± SEM of n = 3 experiments each containing 3 replicates. (b) (i) ONS76 3D spheroids were treated with vincristine (VCR; 1 nM) in combination with vardenafil (VAR; 10 µM) for 72 h. Images were taken immediately after treatment to measure changes in spheroid volume relative to the vehicle-treated control. There was no difference in volume after vardenafil-only treatment. Vincristine efficacy could be potentiated when treated in combination with vardenafil. Error bars represent the mean ± SEM of n ≥ 3 experiments each containing 3 replicates. Significance was calculated using one-way ANOVA analyses with Sidak’s multiple comparisons post-hoc test (ns = not significant, ****p ≤ 0.0001). (ii) Continual monitoring of the effects of combined vincristine and vardenafil treatment (blue) showed a significant continual reduction in spheroid volume following treatment compared to vincristine alone (red). Significance differences between single and combination treatment were calculated using repeated measures two-way ANOVA analyses with Tukey’s multiple comparisons post-hoc test (*p ≤ 0.05, ***p ≤ 0.01, ****p ≤ 0.0001).
