Memorial Sloan Kettering scientists have discovered that leukemia cells expressing high levels of Hox genes are sensitive to DOT1L inhibitor therapy. This therapy, thought to work for MLL-rearranged leukemias, has been effective in Phase 1 clinical trials, achieving the proof of concept (POC) milestone in early 2014 due to objective patient response to the drug. Our scientists’ discovery broadens the patient cohort that can benefit from DOT1L inhibitors to include those cases with NPM1 mutations and NUP98/NSD1 translocations that account for ~40% of all Acute Myelogenous Leukemia (AML) cases.
Our scientists have identified four biomarkers that can be used to amplify the Hox cluster members HOXA4, HOXA5, HOXA7, and HOXA9 by RT-PCR analysis from patient blood sample, bone marrow sample, or lymph node sample. If highly expressed in the tumor samples compared to a wild type control, then this indicates that the patients can benefit from DOT1L inhibitor therapy. This discovery significantly expands the patient cohort for this successful therapy.
- Novel use for an existing treatment that is already succeeding in Phase 1 clinical trials.
- This discovery broadens patient group that can benefit from the effective DOT1L inhibitor therapy by ~35% of adult AML cases and ~ 16% of pediatric AML cases.
There are over 14,590 new AML cases per year in the US exhibiting a 25% survival rate, the lowest amongst leukemias. Currently, the DOT1L inhibitor therapy is effective against one type of human AML, the MLL-rearranged leukemia, which accounts for 20% of AML cases. These biomarkers identify and broaden the patient group that can benefit from DOT1L inhibitor therapy to NPM1-AML, which accounts for ~35% of all AML cases, and to NUP98/NSD1-AML which accounts for ~16% of pediatric AML.
Leukemia, DOT1L inhibitor therapy, biomarker
PCT Application filed, Number PCT/US2014/049641
Scott A. Armstrong, MD, PhD, Laboratory Head, Cancer Biology & Genetics Program, Sloan Kettering Institute, Memorial Sloan Kettering