4.5. Cell viability assay

Cell viability was evaluated by MTT assay (Sigma-Aldrich, St. Louis, MO, USA), essentially as previously described³⁰. In particular, for initial screening all compounds were used at a fixed concentration of 40 μM for 48 h in the three PC cell lines. In concentration-response curves, MTT assays were carried out by incubating PC cell lines, or the normal fibroblast cell line with the most active molecules, at concentrations ranging from 0 μM to 54 μM for 48 h.