FOXO transcription factors are critical regulators of cell homeostasis and steer cell death, differentiation and longevity in mammalian cells. By combined pharmacophore-modelling-based in silico and fluorescence polarization-based screening we identified small molecules that physically interact with the DNA-binding domain (DBD) of FOXO3 and modulate the FOXO3 transcriptional program in human cells. The mode of interaction between compounds and the FOXO3-DBD was assessed via NMR spectroscopy and docking studies. We demonstrate that compounds S9 and its oxalate salt S9OX interfere with FOXO3 target promoter binding, gene transcription and modulate the physiologic program activated by FOXO3 in cancer cells. These small molecules prove the druggability of the FOXO-DBD and provide a structural basis for modulating these important homeostasis regulators in normal and malignant cells.
All data generated or analyzed during this study are included in manuscript and supporting files.
- Judith Hagenbuchner
- Veronika Obsilova
- Tomas Obsil
- Michael J Ausserlechner
- Veronika Obsilova
- Tomas Obsil
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Xavier Darzacq, University of California, Berkeley, United States
© 2019, Hagenbuchner et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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