An antitumor alkaloid isolated from VINCA ROSEA. (Merck, 11th ed.)

Vincristine is only found in individuals that have used or taken this drug. It is an antitumor alkaloid isolated from Vinca Rosea. (Merck, 11th ed.) The antitumor activity of Vincristine is thought to be due primarily to inhibition of mitosis at metaphase through its interaction with tubulin. Like other vinca alkaloids, Vincristine may also interfere with: 1) amino acid, cyclic AMP, and glutathione metabolism, 2) calmodulin-dependent Ca²⁺-transport ATPase activity, 3) cellular respiration, and 4) nucleic acid and lipid biosynthesis. Vincristine is indicated for the treatment of acute leukaemia, malignant lymphoma, Hodgkin's disease, acute erythraemia, and acute panmyelosis. Vincristine sulfate is often chosen as part of polychemotherapy because of lack of significant bone marrow suppression (at recommended doses) and of unique clinical toxicity (neuropathy).