Inhibitors of protein deacetylases have recently been established as a novel therapeutic principle for several human diseases, including cancer. The original notion of the mechanism of action of these compounds focused on the epigenetic control of transcriptional processes, especially of tumor suppressor genes, by interfering with the acetylation status of nuclear histone proteins, hence the name histone deacetylase inhibitors was coined. Yet, this view could not explain the high specificity for tumor cells and recent evidence now suggests that non-histone proteins represent major targets for protein deacetylase inhibitors and that the post-translational modification of the acetylome is involved in various cellular processes of differentiation, survival and cell death induction.
Keywords: Epigenetics; Histone code; Histone deacetylase inhibitors; Posttranslational modifications; Unfolded protein response.