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Brinch, S. A.

Publications and source records attributed to Brinch, S. A..

3 recordsLinked to original sources

Tankyrase inhibition demonstrates anti-fibrotic effects in preclinical pulmonary fibrosis models

BackgroundIdiopathic pulmonary fibrosis (IPF) is a progressive and fatal lung disease with limited treatment options. Although transforming growth factor beta 1 (TGFB1, TGF{beta}) is a key driver of fibrosis, additional signaling pathways, including wingless-type mammary tumor virus integration site (WNT)/{beta}-catenin and yes-associated protein 1 (YAP), contribute to IPF pathogenesis. Clinical data indicate that inhibition of TGF{beta} alone provides limited efficacy or is associated with toxicity, underscoring the need for alternative therapeutic approaches. Tankyrase (TNKS) 1 and 2 are post-translational regulators of WNT/{beta}-catenin and YAP signaling and therefore represent promising antifibrotic targets. OM-153, a potent and selective TNKS inhibitor, exhibits pharmacological properties suitable for preclinical development in IPF. MethodsPrimary normal human lung fibroblasts (NHLF), Scar-in-a-Jar assays, lung-on-a-chip models, and precision-cut lung slices (PCLS) from non-pulmonary fibrosis (non-PF) tissue were stimulated with an IPF-relevant cytokine cocktail (IPF-RC) designed to accurately recapitulate the pro-fibrotic environment and compared to TGF{beta}. These models, with bleomycin-challenged mice and PCLS from end-stage pulmonary fibrosis (PF) patients, were treated with OM-153. Fibrosis markers, extracellular matrix (ECM) components, and signaling pathway-specific gene expression or protein markers were assessed by real-time qRT-PCR, RNA sequencing, immunoblotting, ELISA, and immunofluorescence. ResultsOM-153 stabilized the direct TNKS targets axin 1 (AXIN1) and angiomotin-like 1 (AMOTL1), suppressed WNT/{beta}-catenin and YAP signaling. In parallel, it reduced profibrotic ECM expression across in vitro, in vivo, and ex vivo IPF models. ConclusionsSelective TNKS inhibition by OM-153 demonstrates broad antifibrotic activity in multiple preclinical models, supporting further development as a potential disease-modifying strategy for IPF. Shareable abstractOur findings show that the potent and selective TNKS inhibitor OM-153 suppresses WNT/{beta}-catenin and YAP signaling, reducing pro-fibrotic ECM expression in preclinical IPF models, supporting TNKS inhibition as a novel antifibrotic strategy.

cell biology↗

Discovery of Tankyrase scaffolding inhibitor specifically targeting the ARC4 peptide binding domain

In the past, development of tankyrase inhibitors has focused on the ADP-ribosyltransferase domain. Targeting tankyrases ability to interact with protein substrates through their ARC domains represents an alternative strategy to be explored as a therapeutic approach against specific protein-protein interactions. In this paper, we employed a FRET-based assay to identify ARC4-binding compounds by screening the EU-OPENSCREEN Pilot and Commercials Diversity libraries. We discovered an effective series of compounds with the same scaffold and through chemical synthesis we obtained the compound S8 (ARCher-142), which binds selectively to ARC4 with potency of 8 {micro}M. NMR analysis and X-ray crystallography allowed us to identify the binding site in ARC4 and to rationalize the observed selectivity. Despite binding exclusively to ARC4, the inhibitor can attenuate the WNT/{beta}-catenin signaling pathway in cells. Our work demonstrates that targeting single ARC domains is possible, offering an inhibition approach tailored to tankyrase ARC4 inhibition. SignificanceTankyrases impact a variety of cellular processes by binding proteins through their ARC domains and the inhibition of these scaffolding functions represents an alternative therapeutic approach to catalytic inhibitors. With a FRET-based high-throughput screening of the EU-OPENSCREEN Pilot and Commercials Diversity libraries we discovered a pyrrolone-based scaffold that is interestingly selective towards ARC4, despite the high conservation of the ARC binding site. Our synthesized compound S8 (ARCher-142) displays an 8 {micro}M potency for TNKS2 ARC4. With NMR and X-ray crystallography we demonstrate that S8 (ARCher-142) competes with the peptide optimized for binding and extends to a unique hydrophobic sub-pocket of ARC4. The compound attenuates the WNT/{beta}-catenin signaling pathway in cells and interestingly offers the possibility to target specific protein-protein interactions mediated by ARC4, paving the way for the development of a pyrrolone-based class of tankyrase scaffolding inhibitors.

biochemistry↗

Substitutions at the C-8 position of quinazolin-4-ones improve the potency of nicotinamide site binding tankyrase inhibitors

Human diphtheria toxin-like ADP-ribosyltransferases, PARPs and tankyrases, transfer ADP-ribosyl groups to other macromolecules, thereby controlling various signaling events in cells. They are considered promising drug targets, especially in oncology, and some small molecule inhibitors have already been developed. These inhibitors typically interact with the nicotinamide binding site and extend along the NAD+ binding groove of the catalytic domain. Quinazolin-4-ones have been explored as promising scaffolds for such inhibitors and we have identified a new position within the catalytic domain that has not been extensively studied yet. In this study, we investigate larger substituents at the C-8 position and, using X-ray crystallography, we demonstrate that nitro- and diol-substituents engage in new interactions with TNKS2, improving both affinity and selectivity. Both nitro- and diol-substituents exhibit intriguing inhibition of TNKS2, with compound 49 displaying an IC50 of 65 nM, while compound 40s IC50 value is 14 nM. Both analogues show efficacy in cell assays and attenuate the tankyrase-controlled Wnt/{beta}-catenin signaling with sub-micromolar IC50. When tested against a wider panel of enzymes, compound 40 displayed high selectivity towards tankyrases, whereas 49 also inhibited other PARPs. The results offer new insights for inhibitor development targeting tankyrases and PARPs by focusing on the subsite between a mobile active site loop and the canonical nicotinamide binding site.

biochemistry↗