HepG2 are adherent cells that were maintained in Dulbecco's Modified Eagle's Medium (DMEM)-F12 supplemented with 1% penicillin/streptomycin and 10% heat-inactivated FBS. Fifty microliters of a 5x10 4 cells/mL suspension were dispensed in white, solid 384well plates (Greiner). Cells were exposed to compounds for 72 hours, after which cell viability was quantified by using CellTiter-Glo®. This reagent measures ATP release based on the mono-oxygenation of luciferin catalyzed by Mg 2+ , ATP and molecular oxygen. EC50 values were calculated from two independent experiments performed in triplicate using GraphPad Prism software.