Potent inhibition of DOT1L as treatment of MLL-fusion leukemia

作者：Scott R. Daigle, Edward J. Olhava, Carly A. Therkelsen, Aravind Basavapathruni, Lei Jin, P. Ann Boriack‐Sjodin, Christina J. Allain, Christine R. Klaus, Alejandra Raimondi, Margaret Porter Scott, Nigel J. Waters, Richard Chesworth, Mikel P. Moyer, Robert A. Copeland, Victoria M. Richon, Roy M. Pollock · 发表于：Blood · 年份：2013 · DOI：10.1182/blood-2013-04-497644 · 被引用次数：744 · 研究领域：Acute Myeloid Leukemia Research、Epigenetics and DNA Methylation、Cancer-related gene regulation

Rearrangements of the MLL gene define a genetically distinct subset of acute leukemias with poor prognosis. Current treatment options are of limited effectiveness; thus, there is a pressing need for new therapies for this disease. Genetic and small molecule inhibitor studies have demonstrated that the histone methyltransferase DOT1L is required for the development and maintenance of MLL-rearranged leukemia in model systems. Here we describe the characterization of EPZ-5676, a potent and selective aminonucleoside inhibitor of DOT1L histone methyltransferase activity. The compound has an inhibition constant value of 80 pM, and demonstrates 37 000-fold selectivity over all other methyltransferases tested. In cellular studies, EPZ-5676 inhibited H3K79 methylation and MLL-fusion target gene expression and demonstrated potent cell killing that was selective for acute leukemia lines bearing MLL translocations. Continuous IV infusion of EPZ-5676 in a rat xenograft model of MLL-rearranged leukemia caused complete tumor regressions that were sustained well beyond the compound infusion period with no significant weight loss or signs of toxicity. EPZ-5676 is therefore a potential treatment of MLL-rearranged leukemia and is under clinical investigation.