daunorubicin
Meaning of daunorubicin: One of the original red chemotherapies, still central to leukemia treatment and capped for life because the heart does not recover from it.
Definition of daunorubicin
Daunorubicin is an anthracycline chemotherapy drug given into a vein, used mainly against acute leukemias. Originally isolated from a soil bacterium, it wedges itself between the strands of DNA and jams topoisomerase II, the enzyme that untangles DNA while a cell copies it, so the strands break and the cell dies. It also generates reactive oxygen that inflicts further damage.
What is it used to treat?
Its main role is in the first round of treatment for acute myeloid leukemia, where it is given over several days alongside a second drug in a schedule that has been the backbone of induction for decades. It also forms part of combination regimens for acute lymphoblastic leukemia, particularly in children, and appears in some lymphoma protocols. The aim of induction is to clear the marrow of leukemic cells so that normal blood production can restart, and the drug is dosed hard enough to do that at the cost of temporarily flattening healthy marrow as well.
Why is there a lifetime limit?
Because the damage it does to heart muscle accumulates and does not reverse. Reactive oxygen generated in heart muscle cells injures them, and those cells are not replaced. Every dose is therefore counted toward a cumulative ceiling covering the whole of a person's life, and any earlier anthracycline treatment counts toward the same total. Weakening of the heart may show up during treatment, or years afterward, which is why survivors of childhood leukemia are followed with heart scans into adulthood. Prior chest radiation, existing heart disease and very young or old age raise the risk at any given dose.
What else does it do?
| Effect | What is behind it |
|---|---|
| Red urine for a day or two | The drug is itself deep red; this is not bleeding |
| Severe damage if it leaks from the vein | It blisters and destroys tissue it touches |
| Low blood counts and infection risk | Marrow cells divide fast and are hit hardest |
| Mouth ulcers, nausea, hair loss | Other fast-dividing tissues |
| A later leukemia in a minority | Blocking topoisomerase II can rearrange chromosomes |
The last of these is the uncomfortable one: a class of drug used to cure leukemia can, years later, cause a different one. It remains uncommon and is weighed against the disease being treated.
Also known as
Used in a sentence
Daunorubicin was given with cytarabine during induction.
Good to know
Anthracycline damage to heart muscle depends on the total dose received across a lifetime and can surface years after treatment ends, so every dose counts toward a cumulative ceiling; the red discoloration of urine that follows a dose is the drug itself, not blood.