Sodium 4-phenylbutyrate (TriButyrate), a transcriptional regulator, reversibly inhibits class I and II histone deacetylases (HDACs )resulting in a global increase in gene expression, decreased cellular proliferation, increased cell differentiation, and the induction of apoptosis in susceptible tumor cell populations.

Tributyrin (Glyceryl tributyrate), a neutral short-chain fatty acid triglyceride, is a stable and rapidly absorbed prodrug of Butyric Acid. Tributyrin diffuses through biological membranes and is metabolized by intracellular lipases, releasing effective butyrate directly into the cell in vivo. Tributyrin has potent proapoptotic, antiproliferative, and differentiation-inducing effects.