Figure 2. Carcinoma cells exposed to vorinostat are significantly more sensitive to CTL-mediated killing.

Human prostate (LNCaP) and breast (MDA-MB-231) carcinoma cells were exposed to vorinostat (3 μM, black bars) or to vehicle (DMSO, open bars) as described in Materials and Methods, prior to being used as targets for antigen-specific CTL lysis using CEA-, brachyury-, MUC1-, or PSA-specific CD8⁺ T cells as effector cells (E:T = 30:1). To verify that effector T cells were HLA-restricted, CTLs were incubated with HLA-A2 negative AsPC-1 pancreatic carcinoma cells exposed to vehicle (DMSO) or vorinostat. Results are presented as mean ± S.E.M. from 3-6 replicate wells, and are representative of 1-4 independent experiments. Asterisks denote statistical significance relative to controls.