Tumor initiation and progression are regulated by epigenetic processes that frequently involve histone deacetylases (HDACs), enzymes that control protein acetylation status and epigentically regulate histone tail, chromatin conformation, protein-DNA interaction, and transcription. HDACs are an integral part of the regulation of multiple processes of life, ranging from gene expressions to protein activities, and high expression of HDACs is commonly found in several types of cancer, indicating its potential usefulness in anticancer therapies.