Research Article

Synergistic Antiproliferative Effects of Combined γ-Tocotrienol and PPARγ Antagonist Treatment Are Mediated through PPARγ-Independent Mechanisms in Breast Cancer Cells

Figure 12

Apoptotic effects of γ-tocotrienol and PPARγ antagonists alone or in combination on (a) cleaved caspase-3, cleaved PARP levels and (b) viable cell number on +SA cells. For Western blot studies, +SA cells were initially plated at 06 cells/100 mm culture dish and maintained on control media for a 3-day culture period. Afterwards, cells were divided into the various treatment groups, media were removed, and cells were exposed to their respective treatment media for a 24 h treatment period. In addition, cells were exposed to their respective treatment media for a 96 h treatment period, where fresh media were added every other day. +SA cells were exposed to treatment media containing 2 μM γ-tocotrienol and 3.2 μM GW9662 or T0070907 alone or in combination. Afterwards, whole cell lysates were prepared from cells in each treatment group for subsequent separation by polyacrylamide gel electrophoresis (50 μg/lane) followed by western blot analysis. In parallel studies, (b) +SA cells were plated at a density of 04 (6 wells per group) in 24-well culture plates and exposed to the same treatments as described above. After a 24 h treatment exposure, viable cell number in all treatment groups was determined using MTT assay. Vertical barsindicate the mean cell count ± SEM in each treatment group. * as compared with vehicle-treated controls.