Figure 1.

(A) Histone deacetylase inhibitors (HDIs) block HDACs expression leading to upregulation of acetylation histone and non-histone protein what resulted in clinical implications. (B) Reversible posttranslational lysine residues acetylation of histones is maintained by HATs and HDACs. Removal of acetyl group by HDACs leads to condensation of chromatin and its inactivation. (C) The multiple roles of HDAC enzymes in cells. Regulation of non-histone proteins (transcription factors, adhesion proteins, cellular proteins, DNA-repair proteins, cell signaling and viral proteins) according to their acetylation state, which indicates that HDACs can influence a multitude of physiological pathways in different cells.