Figure 3. Vorinostat-induced immunogenic modulation of MDA-MB-231 carcinoma cells is mediated by HDAC1.

MDA-MB-231 cells were exposed to siRNA control or targeting HDAC1 for 24 h prior to being exposed to vehicle (DMSO) or vorinostat (3 μM) as described in Materials and Methods. A. At the end of treatment, total cell lysates were examined by Western blotting to determine expression of HDAC1. GAPDH was used as internal control for total protein levels. Silencing ratio denotes HDAC1 protein expression relative to GAPDH, further normalized to protein levels after treatment in the presence of silencing RNA control. B. At the end of treatment, MDA-MB-231 cells were used as targets in a CTL-lysis assay where effector brachyury-specific CD8⁺ T cells were used at an E:T ratio of 30:1. Results are presented as mean ± S.E.M. from 4-6 replicate wells. Asterisks denote statistical significance relative to controls (*P = 0.002). Data is representative of two independent experiments.