Growth inhibition and apoptosis of ovarian cancer cells induced by proteasome inhibitors. A, SKOV3, OVCAR3 or A2870 cells were treated with the indicated concentrations of MG132 for 24 h, and cell viability was measured using MTT assay. B, SKOV3, OVCAR3 or A2870 cells were treated with 5 μM of MG132 for 24 h, and nuclear morphology was analyzed using Hoechst 33258 staining. C, SKOV3, OVCAR3 or A2870 cells were treated with vehicle, bortezomib (BZ), epoxomicin (Epox), lactacystin (Lacta), or MG132 for 24 h, and Western blot analysis was performed using the indicated antibodies. D, SKOV3, OVCAR3 or A2870 cells were treated with the indicated concentrations of MG132 for 24 h, and apoptotic cells were measured using Annexin V and PI double staining followed by flow cytometry. *, P<0.01.