Anthracyclines are a large group of anticancer compounds whose common characteristic is a basic tetracyclic skeleton. The first derivatives of antracycline, doxorubicin and daunorubicin, were isolated from the culture of Streptomyces peucetius in the early 1960s. The main producer of anthracyclines remains S. peucetius, but these natural products can be produced by a broad spectrum of Streptomyces species. Anthracyclines are used to treat various forms of cancer, such as lung cancer, prostate cancer, various types of leukaemia, osteogenic bone tumours and Hodgkin's lymphoma, but are most commonly used to treat breast cancer and acute myeloid leukaemia. However, their use in clinical practice is limited due to the adverse side effects, such as cardiotoxicity. Cardiotoxicity is manifested as subclinical reduction of the functions of the left heart ventricle or obvious cardiomyopathy. The main mechanisms of action of anthracyclines are reversible intercalation into DNA, formation of free radicals, binding and alkylation of DNA, DNA cross-linking, separation of DNA chains, direct effect on the membrane and induction of apoptosis. The primary molecular targets of anthracyclines are DNA topoisomerases and reversible intercalation into DNA. In order to reduce the side effects and increase the biological activity of the anthracyclines, fluorine or nitrogen atoms are often added to the basic tetracycline sceleton and. the sugar moiety can also be modified. In addition, antracycline have been studied, for different applications and a lot of efforts are directed towards screening of novel anthracycline analogues.
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