Anthracycline: A member of a family of chemotherapy drugs that are also antibiotics. The anthracyclines act to prevent cell division by disrupting the structure of the DNA and terminate its function. They do so in two ways: (1) they intercalate into the base pairs in the DNA minor grooves; and (2) they cause free radical damage of the ribose in the DNA. The anthracyclines are frequently used in leukemia therapy. The anthracyclines include daunorubicin (Cerubidine), doxorubicin (Adriamycin, Rubex), epirubicin (Ellence, Pharmorubicin), and idarubicin (Idamycin).