Doxorubicin or adriamycin or hydroxyldaunorubicin is a DNA-interacting drug widely used in chemotherapy. It is an anthracycline and structurely closely related to daunomycin, and also intercalates DNA. It is commonly used in the treatment of uterine cancer and ovarian cancer, as well as some other cancers.
Doxil® is a liposome-encapsulated dosage form of doxorubicin made by Johnson & Johnson. Its main benefits are a reduction in cardiotoxicity. It follows the similar preparation of daunorubicin in a liposomal carrier.
Mechanism of Action
Doxorubicin acts by binding to
DNA where it can inhibit the progression of the enzyme
topoisomerase II, which unwinds DNA for
transcription. Doxorubicin stabilizes the topoisomerase II complex after it has broken the DNA chain for replication, preventing the DNA double helix from being resealed and thereby stopping the process of replication.
Side effects
Acute side-effects of doxorubicin can include nausea, vomiting, and heart
arrhythmias. It can also cause a decrease in white blood cells and
alopecia (hair loss). When the cumulative dose of doxorubicin reaches 450mg/m2, the risks of developing cardiac side effects, including
congestive heart failure, dilated
cardiomyopathy, and death, dramatically increase. Doxorubicin cardiotoxicity is characterized by a dose-dependent decline in
mitochondrial
oxidative phosphorylation. Reactive oxygen species, generated by the interaction of doxorubicin with iron, can then damage the myocytes (heart cells), causing myofibrillar loss and cytoplasmic vacuolization. Additionally, some adults who were treated with doxorubicin when they were children have developed dilated cardiomyopathy up to 15 years later.
Clinical Use
Doxorubicin is a commonly used to treat
Hodgkin's disease,
breast cancer,
lung cancer,
soft tissue sarcoma,
Kahler's disease (multiple myeloma) and recurring instances of
ovarian cancer. Commonly used doxorubicin-containing regimens are ABVD (Adriamycin, Bleomycin, Vinblastine, Dacarbazine), CHOP (Cyclophosphamide, Adriamycin, Vincristine, Prednsione) and FAC (5-Fluorouracil, Adriamycin, Cyclophosphamide).
Experimental
Combination therapy experiments with
sirolimus (rapamycin) and doxorubicin have shown promise in treating
Akt-positive lymphomas. See
sirolimus.
External links
Chemotherapeutic agents
Doxorubicin | Doxorubicine | Doxorubicin | Doxorubicine | Doksorubicyna