A, Serum-depleted HepG2 cells were pretreated with increasing concentrations of O-1602 for 30 min followed by the addition of 10 nM T1117. B, Bars represent the average T1117-AUC ± S.D. (n=3 independent experiments). C and D, HepG2 cells seeded in 96-well plates were serum-starved and subjected to O-1602 (C) and LPI (D) treatment at the indicated concentrations for 30 min. Cellular incorporation of T1117 was carried out as indicated in Material and Methods, method 2. Bars indicate mean ± S.D. of averaged T1117 ROI intensities from 8 wells across two independent experiments. **, *** P < 0.01 and 0.001, respectively.