What common pediatric chemo drug is classified as a plant alkaloid?

Vincristine is classified as a plant alkaloid, specifically derived from the periwinkle plant (Catharanthus roseus). This drug is commonly used in pediatric chemotherapy regimens, particularly for treating various forms of leukemia and tumors such as Wilms tumor and neuroblastoma.

The mechanism of action of vincristine involves its ability to inhibit mitosis by binding to tubulin and preventing the formation of microtubules, which interrupts the cell cycle at the metaphase stage. This is particularly effective in rapidly dividing cancer cells, making it a valuable component in combination chemotherapy regimens used in children.

The other drugs mentioned have different classifications and mechanisms of action. Cisplatin is a platinum-based chemotherapeutic agent that binds to DNA, causing cross-linking and subsequently triggering apoptosis. Hydroxyurea is an antimetabolite that inhibits DNA synthesis, and Dacarbazine is an alkylating agent that adds alkyl groups to DNA. Each of these is used in specific contexts but does not fall under the category of plant alkaloids like vincristine does.