Figure 3.

Dose–response curves of 5‐(3′,4′‐dihydroxyphenyl)valeric acid (PVA) A) and 5‐(3′,4′‐ dihydroxyphenyl)‐γ‐valerolactone (PVL) B) on 3D HCT116 EGFP spheroids in aggregation and on formed spheroids C and D). The concentration tested for (3′,4′‐dihydroxyphenyl)‐γ‐valerolactone on spheroids in aggregation ranged from 30 to 100 µM for 72 h, while the remaining experiments ranged from 3 to 100 µM for 72 h. Spheroid integrity was quantified by High Content Imaging System Operetta (Perkin Elmer) and expressed as a percentage of the vehicle‐treated controls (DMSO 0.05%). IC₅₀ was calculated applying dose–response‐inhibition nonlinear regression analysis. The data were calculated as the mean ± SEM from at least four independent experiments. Spheroids were imaged on the High Content Imaging System Operetta (Perkin Elmer) with 10XLWD objective in brightfield and green fluorescent channels (merged images) at different concentrations. Scale bars, 200 µm.