Characterization of antiproliferative effects of T0901317 treatment in ovarian carcinoma cells. A2780, CaOV3 and SKOV3 cells were cultured and treated with DMSO (♦ blue) or T0901317 at a concentration of 5 μM (■ pink), 10 μM (▲ yellow), 20 μM (X, light blue), 40 μM (X, purple) or 50 μM (● red) for 24 h, 48 h or 72 h (A-C). Proliferation status was determined by the CyQuant proliferation assay. T0901317 significantly inhibits cellular proliferation in all cell lines in a dose-dependent and time-dependent manner. Each value is the mean ± SD of three independent experiments, and the proliferation value is expressed as percentage of vehicle-treated cells (DMSO). (*P < 0.0001 vs. untreated cells). After culturing with vehicle (DMSO) or with T0901317 for the indicated time-points at a concentration of 10 μM, cells were stained with propidium iodide as detailed in Material and Methods and examined by flow cytometry to determine cell cycle phase distribution (D). After 24, 48 or 72 hours of treatment, the LXR agonist T0901317 decreased the percentage of cells in S phase and increased the percentage of cells in the G0/G1 phase, indicating a cell cycle arrest at the G1-S checkpoint. The percentage of cells in G0/G1 phase increases in a time-dependent manner. Results are the mean of three independent experiments and are expressed as percentage of cells, presented as mean ± SD. *P < 0.001. CaOV3 cells were grown in media supplemented with 10% FBS for 48 hours in presence of vehicle (DMSO) or the indicated concentrations of T0901317 (5 μM to 40 μM). Whole-cell extract was obtained and 60-90 μg of protein was analyzed for phospho-pRb (E), p21 (F) or p27 (G) protein levels by Western blot analysis.