Fig. 3: OCD activity in 3D co-culture models.

a Representative images of heterotypic 3D co-culture spheroids composed of cell tracker-stained A498-ST cells (green), NHDFα (blue) and ECRF24 cells (red), and the 3D spheroid development over the first 24 h. Scale bar represents 150 µm. b Spheroid cell metabolic activity in A498-ST 3D co-cultures after treatment with Ctrl, ODC, corresponding monotherapies or 1 µM sunitinib (positive control). The results were obtained after administering each treatment for 72 h at two treatment schedules, i.e. (i) day 2–5 after spheroid formation (left graph), or (ii) day 4–7 after spheroid formation (right graph). Error bars represent the standard deviation (metabolic activity measurements, N = 2–3). Significances of **p < 0.005 define the difference of the ODC treatment to the Ctrl and each corresponding monotherapy determined with an ordinary one-way ANOVA with Tukey’s post hoc test.