Idarubicin

Idarubicin is an orally active and potent anthracycline antileukemic agent. Idarubicin inhibits the topoisomerase II interfering with the replication of DNA and RNA transcription. Idarubicin shows induction of DNA damage. Idarubicin inhibits DNA synthesis and of c-myc expression. Idarubicin inhibits the growth of bacteria and yeasts^{[1][2][3][4][5]}. In Vitro: The IC₅₀ of idarubicin is 3.3 ± 0.4 ng/mL on MCF-7 monolayers and 7.9 ± 1.1 ng/mL in multicellular spheroids^[1].
Idarubicin shows a greater cytotoxicity than daunorubicin or doxorubicin in various in vitro systems. This has been attributed to a better ability of idarubicin to induce the formation of topoisomerase II -mediated DNA breaks^[2].
Idarubicin is about 57.5-fold and 25-fold more active than doxorubicin and epirubicin, respectively^[3].
Idarubicin produces a concentration-dependent reduction in MCF-7 cell growth, with an IC₅₀ of approximately 0.01 μM. Idarubicin produces a concentration-dependent inhibition of DNA synthesis and a time- and concentration-dependent suppression of c-myc expression^[4].