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Vinca alkaloids are a family of anticancer alkaloids that include vinblastine, vincristine, vindesine, and vinorelbine. The first two chemicals occur naturally and are found in the Madagascar periwinkle, Catharanthus roseus (the plant was formerly classified as Vinca rosea, which led to these compounds becoming called Vinca alkaloids).

These alkaloids all work against cancer by inhibiting mitosis (cell division) in metaphase. These alkaloids bind to tubulin, thus preventing the cell from making the spindles it needs to be able to move its chromosomes around as it divides (this is similar to the action of colchicine, but is different from the action of paclitaxel, which interferes with cell division by keeping the spindles from being broken down).

These alkaloids also seem to interfere with cells' ability to synthesize DNA and RNA. They are all administered intravenously in their sulfate form once a week; these solutions are fatal if they're administered any other way, and can cause a lot of tissue irritation if they leak out of the vein.