ABSTRACT
Histone deacetylase inhibitors (HDACi) represent a novel class of anticancer compounds that inhibit tumor cell growth and/or survival by inducing cell cycle arrest at the G1 or G2/M phases, differentiation, or apoptosis, inhibiting angiogenesis and tumor cell metastasis, and activating the host immune response. A large number of structurally diverse HDACi exist that have been purified from natural sources and synthetically developed. Interestingly, HDACi were initially identified based on their ability to induce differentiation of Friend erythroleukemia cells, and were only subsequently discovered to inhibit HDACs. The short-chain fatty acids are the least potent inhibitors, possess a short half-life, and may possess other targets in addition to HDACis. Nonetheless, this class of HDACi is being used in the clinic alone and in combination with other agents for the treatment of cancer. The benzamides are less potent HDACi than the hydroxamate and cyclic tetrapeptide inhibitors but are more potent than the short-chain fatty acids.
