HDAC9 and prostate cancer: Next, we focused our study on histone acetylation because ZEB1, as a repressor, recruits class I and II histone deacetylases (HDACs) in pancreatic tumors and nicotinamide adenine dinucleotide (NAD)-dependent HDAC SIRT1 in prostate cancers, while in colon cancer cells, ZEB1 recruits BRG1 to repress E-cadherin.