Cunningham, L., Finckbeiner, S., Hyde, R.K., Southall, N., Marugan, J., Yedavalli, V.R., Dehdashti, S.J., Reinhold, W.C., Alemu, L., Zhao, L., Yeh, J.R., Sood, R., Pommier, Y., Austin, C.P., Jeang, K.T., Zheng, W., and Liu, P. (2012) Identification of benzodiazepine Ro5-3335 as an inhibitor of CBF leukemia through quantitative high throughput screen against RUNX1-CBFbeta interaction. Proceedings of the National Academy of Sciences of the United States of America. 109(36):14592-14597.
Core binding factor (CBF) leukemias, those with translocations or inversions that affect transcription factor genes RUNX1 or CBFB, account for <24% of adult acute myeloid leukemia (AML) and 25% of pediatric acute lymphocytic leukemia (ALL). Current treatments
for CBF leukemias are associated with significant morbidity and mortality, with a 5-y survival rate of <50%. We hypothesize
that the interaction between RUNX1 and CBFβ is critical for CBF leukemia and can be targeted for drug development. We developed
high-throughput AlphaScreen and time-resolved fluorescence resonance energy transfer (TR-FRET) methods to quantify the RUNX1–CBFβ
interaction and screen a library collection of 243,398 compounds. Ro5-3335, a benzodiazepine identified from the screen, was
able to interact with RUNX1 and CBFβ directly, repress RUNX1/CBFB-dependent transactivation in reporter assays, and repress runx1-dependent hematopoiesis in zebrafish embryos. Ro5-3335 preferentially killed human CBF leukemia cell lines, rescued preleukemic
phenotype in a RUNX1–ETO transgenic zebrafish, and reduced leukemia burden in a mouse CBFB–MYH11 leukemia model. Our data thus confirmed that RUNX1–CBFβ interaction can be targeted for leukemia treatment and we have identified
a promising lead compound for this purpose.