Topotecan

Part of speech: noun

Definitions

1. A semisynthetic anticancer drug derived from camptothecin that blocks the topoisomerase I enzyme and is used to treat certain cancers
2. An antitumor agent, related to camptothecin, that interferes with DNA unwinding and is given to patients with ovarian or small cell lung cancer
3. A chemical compound used in cancer chemotherapy that halts cell division by inhibiting the topoisomerase I enzyme needed for DNA replication

Etymology: Topotecan is a modern pharmaceutical coinage rather than an ancient word, and its name is built from parts that tell you what it is. The "-tecan" ending belongs to a family of anticancer drugs derived from camptothecin, a compound first isolated in 1966 from the Chinese tree Camptotheca acuminata. The "topo-" element refers to topoisomerase, the enzyme that the drug blocks: topoisomerase I unwinds DNA so cells can copy it, and topotecan jams that enzyme so the DNA breaks and the cancer cell dies. The name was assigned by pharmaceutical developers as part of a naming scheme for drugs in this class, so it is best understood as a technical compound of "topo" and the camptothecin-derived suffix rather than a word with a long history. It was approved for medical use in the late 1990s, and the name entered medical vocabulary at that time.