Belinostat (PXD101) is a class I, II and IV histone deacetylase (HDAC) enzyme inhibitor with a broad antineoplastic activity. HDACs catalyze the removal of acetyl groups from the N-acetylated lysine residues of histones and some non-histone proteins. Histones are the basic protein building blocks of chromatins in the nucleus of a cell, which contain DNA coiled around the histone unit. They compact DNA into a smaller volume, and also play a role in DNA replication, repair, mitosis, and gene expression. HDAC inhibitors block angiogenesis, arrest cell growth, and lead to cell-cycle arrest and apoptosis in tumor cells. Belinostat has been used for the treatment of T-cell lymphoma (PTCL). (The product is for research purpose only.)