Small molecule inhibitors of a human recombination-associated ATPase, RAD54

Ehmsen, K. T.; Ang, K. K. H.; Wright, W. D.; Davies, J. L.; Younis, Y.; Birman, Y.; Bryant, C.; Gallardo-Godoy, A.; Renslo, A. R.; Neitz, R. J.; Arkin, M. R.; Heyer, W.-D.

doi:10.1101/614586

bioRxiv · 10.1101/614586

Small molecule inhibitors of a human recombination-associated ATPase, RAD54

Ehmsen, K. T.·Ang, K. K. H.·Wright, W. D.·Davies, J. L.·Younis, Y.·Birman, Y.·Bryant, C.·Gallardo-Godoy, A.·Renslo, A. R.·Neitz, R. J.·Arkin, M. R.·Heyer, W.-D.

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Abstract

Homologous recombination (HR) is a principal support pathway for DNA replication and for recovery from DNA breaks and interstrand crosslinks, making it a rational target for inhibition in cancer therapy. The ATPase RAD54 functions in molecular events that promote DNA sequence-preservation during HR-mediated damage repair, including homology search, DNA strand exchange, and transition to DNA repair synthesis within a displacement loop intermediate. We developed a high-throughput biochemical screen to identify small-molecule inhibitors of human RAD54, using a phosphate detection assay to monitor RAD54 ATPase activity in the presence of double-stranded DNA (dsDNA). After filtering potential DNA intercalators and frequent hitters, we identified two chemotypes that reproducibly inhibited RAD54 ATPase in vitro. We evaluated these chemotypes for inhibition of RAD54-dsDNA binding and cancer cell survival. A halogenated carbazole/dihydroacridine scaffold inhibited a panel of SWI2/SNF2-related ATPases but not VCP/p97, an unrelated ATPase. Small molecules that interfere with key steps in HR-- such as inhibitors of RAD54--may expose DNA repair-dependent vulnerabilities in cancer cells.

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Ehmsen, K. T., Ang, K. K. H., Wright, W. D., Davies, J. L., Younis, Y., Birman, Y., Bryant, C., Gallardo-Godoy, A., Renslo, A. R., Neitz, R. J., Arkin, M. R., Heyer, W.-D.. 2019-04-19. Small molecule inhibitors of a human recombination-associated ATPase, RAD54. https://doi.org/10.1101/614586

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