Vincristine Sulfate, a dimeric Vinca alkaloid, has been shown to bind to Tubulin via a protein self association reaction. This compound acts as a Tubuiln inhibitor by binding to sites at the ends of microtubules, which regulate the inhibition of Tubulin dimer addition to microtubule ends. Experiments have reported Vincristine Sulfate to demonstrate a capacity to suppress growth of proliferating cells through marked apoptosis and cell cycle arrest at G2/M. The cell death caused by this agent seems to result in a sustained accumulation of endogenous ceramide levels. Ceramide, has been proposed as a lipid second messenger with specific antiproliferative mediating responses. Vincristine Sulfate is an inhibitor of MAO. Vincristine Sulfate is also a substrate of PGP and CYP3A4.