Small-Molecule Chemical Probe Rescues Cells from Mono-ADP-Ribosyltransferase ARTD10/PARP10-Induced Apoptosis and Sensitizes Cancer Cells to DNA Damage

Abstract

SUMMARYMembers of the human diphtheria toxin-likeADP-ribosyltransferase (ARTD or PARP) family play important roles in regulating biological activities by mediating either a mono-ADP-ribosylation MARylation) of a substrate or a poly-ADP-ribosylation (PARylation). ARTD10/PARP10 belongs to the MARylating ARTDs (mARTDs) subfamily, and plays important roles in biological processes that range from cellular signaling, DNA repair, and cell proliferation to immune response. Despite their biological and disease relevance, no selective inhibitors for mARTDs are available. Here we describe a small-molecule ARTD10 inhibitor, OUL35, a selective and potent inhibitor for this enzyme. We characterize its selectivity profile, model its binding, and demonstrate activity in HeLa cells where OUL35 rescued cells from ARTD10 induced cell death. Using OUL35 as a cell biology tool we show that ARTD10 inhibition sensitizes the cells to the hydroxyurea-induced genotoxic stress. Our study supports the proposed role of ARTD10 in DNA-damage repair and provides a tool compound for selective inhibition of ARTD10-mediated MARylation.3

Forced Self-Modification Assays as a Strategy to Screen MonoPARP Enzymes

“…1 Ribon Therapeutics Inc., Cambridge, MA, USA 2 Evotec SE, Hamburg, Germany inhibitors, and of those published, potencies and intra-PARP family selectivity are modest. [3][4][5][6][7][8][9][10] Approved drugs that target PARP1 and PARP2 (niraparib and talazoparib) or PARP1, PARP2, and PARP3 (olaparib and rucaparib) are now in use for the treatment of a variety of cancers, and potent and selective inhibitors of PARP5a and PARP5b (tankyrases 1 and 2) have been reported to have antiproliferative activity in cancer cell lines and in vivo models. 11 MonoPARPs have been reported to have important roles in immunology, inflammation, and cancer; [12][13][14] however, these studies have relied almost exclusively on genetic perturbation techniques that often do not distinguish loss of catalytic activity from loss of the entire protein.…”

The role of ADP-ribose metabolism in metabolic regulation, adipose tissue differentiation, and metabolism

“…Clinically available PARP inhibitors include ABT-888 (Veliparib from Abbott/Abbvie) rucaparib (Rubraca from Agouron/Pfizer/Clovis), talazoparib (Talzenna from Lead/Biomarin/Medivation/Pfizer), olaparib (Lynparza from KuDos Pharmaceuticals/Astra-Zeneca+Merck), and niraparib (Zejula from Merck/ Tesaro/GSK) (for detailed review, see Slade 2020;Curtin and Szabo 2013). Although, none of the current PARP inhibitors seem to discriminate between PARP enzymes (Wahlberg et al 2012), enzyme-specific inhibition of mono-PARP enzymes may be possible (Venkannagari et al 2016;Upton et al 2017;Holechek et al 2018).…”

Small Molecule Microarray Based Discovery of PARP14 Inhibitors

“…Surprisingly, the second crystal structure shows that H5 bound to PARP14 in a different fashion (Figure S13); its distal phenyl group made hydrophobic interactions with the Val1773 and Val1784 side chains in a site around the small hydrophobic residue that characterizes the mono‐ADP‐ribosyltransferases of the PARP family, Leu1782 . This was an interesting observation because binding at the subsite near the A‐loop might provide a means to accomplish truly selective inhibition even within the mono‐ADP‐ribosyltransferases . Notwithstanding, our PARP14/ H10 structure clearly showed that, by using the bidentate strategy, selective PARP14 inhibitors could be generated by engaging a 3‐sulfonamide benzoic acid in the adenine binding site.…”