Suramin potently inhibits binding of the mammalian high mobility group protein AT-hook 2 to DNA

Su, L.; Bryan, N.; Battista, S.; Freitas, J.; Garabedian, A.; DAlessio, F.; Romano, M.; Falanga, F.; Fusco, A.; Kos, L.; Chambers, J.; Fernandez-Lima, F.; Chapagain, P. P.; Vasile, S.; Smith, L.; Leng, F.

doi:10.1101/838656

bioRxiv · 10.1101/838656

Suramin potently inhibits binding of the mammalian high mobility group protein AT-hook 2 to DNA

Su, L.·Bryan, N.·Battista, S.·Freitas, J.·Garabedian, A.·DAlessio, F.·Romano, M.·Falanga, F.·Fusco, A.·Kos, L.·Chambers, J.·Fernandez-Lima, F.·Chapagain, P. P.·Vasile, S.·Smith, L.·Leng, F.

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Abstract

The mammalian high mobility group protein AT-hook 2 (HMGA2) is a multi-functional DNA-binding protein which plays important roles in tumorigenesis and adipogenesis. Previous results showed that HMGA2 is a potential therapeutic target of anticancer and anti-obesity drugs by inhibiting its DNA-binding activities. Here we report the development of a miniaturized, automated AlphaScreen high throughput screening (HTS) assay to identify inhibitors targeting HMGA2-DNA interactions. After screening the LOPAC1280 compound library, we discovered that suramin, a negatively charged antiparasitic drug potently inhibits the HMGA2-DNA interaction. Our results also show that the inhibition is through suramin binding to the AT-hooks of HMGA2, therefore blocking its DNA binding capacity. Furthermore, we demonstrate that suramin can induce brain tumor stem cells differentiation into cells with neurite-like structures, a process triggered by disrupting HMGA2-DNA interactions. Since suramin has strong antitumor and anti-metastasis activities, our discovery suggests that HMGA2 and HMGA2-like proteins may be the cellular target of this century-old drug.

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Su, L., Bryan, N., Battista, S., Freitas, J., Garabedian, A., DAlessio, F., Romano, M., Falanga, F., Fusco, A., Kos, L., Chambers, J., Fernandez-Lima, F., Chapagain, P. P., Vasile, S., Smith, L., Leng, F.. 2019-11-12. Suramin potently inhibits binding of the mammalian high mobility group protein AT-hook 2 to DNA. https://doi.org/10.1101/838656

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