UBE2N, an E2 ubiquitin-conjugating enzyme, has emerged as a promising therapeutic target in oncology due to its critical roles in DNA damage repair and NF-κB signalling. While covalent inhibitors have shown promising preclinical results, non-covalent inhibitors display increased selectivity and reduced off-target effects. However, structural and mechanistic data for non-covalent UBE2N inhibitors remain scarce. To address this gap, we implemented a dual in silico strategy combining structure-based molecular docking and ligand-based 3D pharmacophore modelling. Screening of a library of ∼19,000 compounds to identify molecules targeting the ubiquitin-binding or cofactor-interacting interfaces of UBE2N, led to the identification of 22 candidates suitable for biological evaluation.Among these, compounds CERMN-2 and CERMN-16 emerged primarily as promising non-covalent inhibitors. CERMN-16, structurally related to the natural compound Variabine B (identified through 3D pharmacophore screening), significantly reduced SKOV-3 ovarian cancer cell viability and enhanced their sensitivity to the PARP inhibitor Olaparib, a phenotype observed upon effective UBE2N inhibition. CERMN-2, identified through our docking strategy, also demonstrated a synergistic effect with Olaparib and showed low toxicity in normal ovarian epithelial cells. Molecular dynamics simulations indicated distinct binding modes for each compound, consistent with their targeted binding sites. Biophysical experiments revealed weak binding of CERMN-16 to UBE2N, whereas CERMN-2 bound UBE2N in two orthogonal assays (Microscale thermophoresis and Nano differential scanning fluorimetry). CERMN-16, and more importantly CERMN-2, therefore represent promising hits for the future development of selective, non-natural, non-covalent UBE2N inhibitors. These results provide new insights into UBE2N inhibition and support further investigation of its therapeutic potential to sensitize ovarian cancer to approved therapeutics.

Advances in cancer treatment have led to a steady increase in the rate of disease remission. However, while many treatment-related adverse effects gradually resolve after therapy, chemotherapy-induced peripheral neuropathy (CIPN) often persists, with no means of prevention or direct treatment available. Herein, we present Carba1, a novel bi-functional carbazole that mitigates neuropathy through two distinct mechanisms. First, by interacting with tubulin, Carba1 reduces the required dose of taxanes, widely used chemotherapy drugs notorious for their toxic side effects, including CIPN. Second, Carba1 activates nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in the NAD salvage pathway, triggering a metabolic rewiring that enhances the resilience of neurons and Schwann cells against chemotherapy-induced toxicity. We demonstrate the neuroprotective efficacy of Carba1 both in vitro, against neurotoxicity induced by paclitaxel (PTX), cisplatin, and bortezomib, and in vivo in a rat model of PTX-induced neuropathy. Importantly, we establish that Carba1 does not compromise the therapeutic efficacy of PTX nor promotes tumor growth. Comparative analyses of Carba1 derivatives further suggest the potential of designing compounds with either dual synergistic and neuroprotective activity or exclusive neuroprotective properties. Altogether, our findings position Carba1 as a promising therapeutic candidate for preventing CIPN, with the potential, if successfully translated to clinical settings, to improve both the quality of life and treatment outcome for cancer patients.

While advances in cancer therapy have improved remission rates, chemotherapy-induced peripheral neuropathy (CIPN) remains a lasting and untreatable side effect. This study introduces Carba1, a bifunctional carbazole compound that protects against CIPN through two mechanisms. First, Carba1 interacts with tubulin, allowing for lower doses of taxanes, common chemotherapeutics known for causing CIPN, without reducing their anticancer effectiveness. Second, Carba1 activates nicotinamide phosphoribosyltransferase (NAMPT), enhancing NAD biosynthesis and boosting the metabolic resilience of neurons and Schwann cells against chemotherapy-induced damage. Carba1 shows strong neuroprotective effects in vitro against paclitaxel, cisplatin, and bortezomib toxicity and in vivo in a rat model of paclitaxel-induced neuropathy. Crucially, Carba1 does not interfere with paclitaxel's tumor-fighting ability or promote tumor growth. Structure-activity analyses of Carba1 derivatives reveal the potential to develop compounds with dual or solely neuroprotective effects. These findings position Carba1 as a promising candidate to prevent CIPN, with potential to enhance both cancer treatment outcomes and patients' quality of life.

Cancer cells are highly dependent on bioenergetic processes to support their growth and survival. Disruption of metabolic pathways, particularly by targeting the mitochondrial electron transport chain complexes (ETC-I to V) has become an attractive therapeutic strategy. As a result, the search for clinically effective new respiratory chain inhibitors with minimized adverse effects is a major goal. Here, we characterize a new OXPHOS inhibitor compound called MS-L6, which behaves as an inhibitor of ETC-I, combining inhibition of NADH oxidation and uncoupling effect. MS-L6 is effective on both intact and sub-mitochondrial particles, indicating that its efficacy does not depend on its accumulation within the mitochondria. MS-L6 reduces ATP synthesis and induces a metabolic shift with increased glucose consumption and lactate production in cancer cell lines. MS-L6 either dose-dependently inhibits cell proliferation or induces cell death in a variety of cancer cell lines, including B-cell and T-cell lymphomas as well as pediatric sarcoma. Ectopic expression of Saccharomyces cerevisiae NADH dehydrogenase (NDI-1) partially restores the viability of B-lymphoma cells treated with MS-L6, demonstrating that the inhibition of NADH oxidation is functionally linked to its cytotoxic effect. Furthermore, MS-L6 administration induces robust inhibition of lymphoma tumor growth in two murine xenograft models without toxicity. Thus, our data present MS-L6 as an inhibitor of OXPHOS, with a dual mechanism of action on the respiratory chain and with potent antitumor properties in preclinical models, positioning it as the pioneering member of a promising drug class to be evaluated for cancer therapy. MS-L6 exerts dual mitochondrial effects: ETC-I inhibition and uncoupling of OXPHOS. In cancer cells, MS-L6 inhibited ETC-I at least 5 times more than in isolated rat hepatocytes. These mitochondrial effects lead to energy collapse in cancer cells, resulting in proliferation arrest and cell death. In contrast, hepatocytes which completely and rapidly inactivated this molecule, restored their energy status and survived exposure to MS-L6 without apparent toxicity.

Tumor heterogeneity and plasticity, driven by Epithelial-Mesenchymal Transition (EMT), enable cancer therapeutic resistance. We previously showed that EMT promotes primary cilia formation, which enables stemness and tumorigenesis in triple-negative breast cancer (TNBC). Here, we establish a role for primary cilia in human TNBC chemotherapeutic resistance. We developed patient-derived organoids, and showed that these recapitulated the cellular heterogeneity of TNBC biopsies. Notably, one of the identified cell states bore a quasi-mesenchymal phenotype, primary cilia, and stemness signatures. We treated our TNBC organoids with chemotherapeutics and observed partial killing. The surviving cells with organoid-reconstituting capacity showed selective enrichment for the quasi-mesenchymal ciliated cell subpopulation. Genomic analyses argue that this enrichment reflects a combination of pre-existing cells and ones that arose through drug-induced cellular plasticity. We developed a family of small-molecule inhibitors of ciliogenesis and show that these, or genetic ablation of primary cilia, suppress chemoresistance. We conclude that primary cilia help TNBC to evade chemotherapy. Significance Cancer cells that activate EMT to acquire a quasi-mesenchymal state form primary cilia to evade chemotherapy in human triple-negative breast cancer. Pharmacological inhibition of primary ciliogenesis counteracts EMT-induced chemoresistance. ### Competing Interest Statement The authors have declared no competing interest.

The X-chromosome-linked inhibitor of apoptosis protein (XIAP) plays a crucial role in controlling cell survival across multiple regulated cell death pathways and coordinating a range of inflammatory signalling events. The discovery of selective inhibitors for XIAP-BIR2, able to disrupt the direct physical interaction between XIAP and RIPK2, offer promising therapeutic options for NOD2-mediated diseases like Crohn's disease, sarcoidosis, and Blau syndrome. The objective of this study was to design, synthesize, and evaluate small synthetic molecules with binding selectivity to XIAP-BIR2 domain. To achieve this, we applied an interdisciplinary drug design approach and firstly we have synthesized an initial fragment library to achieve a first XIAP inhibition activity. Then using a growing strategy, larger compounds were synthesized and one of them presents a good selectivity for XIAP-BIR2 versus XIAP-BIR3 domain, compound 20 c. The ability of compound 20 c to block the NOD1/2 pathway was confirmed in cell models. These data show that we have synthesized molecules capable of blocking NOD1/2 signalling pathways in cellulo, and ultimately leading to new anti-inflammatory compounds.

The chemokine receptor CXCR4 and its ligand CXCL12 regulate leukocyte trafficking, homeostasis and functions and are potential therapeutic targets in many diseases such as HIV-1 infection and cancers. Here, we identified new CXCR4 ligands in the CERMN chemical library using a FRET-based high-throughput screening assay. These are bis-imidazoline compounds comprising two imidazole rings linked by an alkyl chain. The molecules displace CXCL12 binding with submicromolar potencies, similarly to AMD3100, the only marketed CXCR4 ligand. They also inhibit anti-CXCR4 mAb 12G5 binding, CXCL12-mediated chemotaxis and HIV-1 infection. Further studies with newly synthesized derivatives pointed out to a role of alkyl chain length on the bis-imidazoline properties, with molecules with an even number of carbons equal to 8, 10 or 12 being the most potent. Interestingly, these differ in the functions of CXCR4 that they influence. Site-directed mutagenesis and molecular docking predict that the alkyl chain folds in such a way that the two imidazole groups become lodged in the transmembrane binding cavity of CXCR4. Results also suggest that the alkyl chain length influences how the imidazole rings positions in the cavity. These results may provide a basis for the design of new CXCR4 antagonists targeting specific functions of the receptor.

This work reports a new chemical structure that (i) displays activity against the human malaria parasite Plasmodium falciparum at 3 stages of the parasitic cycle (blood stage, hepatic stage, and sexual stages), (ii) remains active against parasites that are resistant to the first-line treatment recommended by the World Health Organization (WHO) for the treatment of severe malaria (artemisinins), and (iii) reduces transmission of the parasite to the mosquito vector in a mouse model. This new molecule family could open the way to the conception of novel antimalarial drugs with an original multistage mechanism of action to fight against Plasmodium drug resistance and block interhuman transmission of malaria.

Paclitaxel is a microtubule stabilizing agent and a successful drug for cancer chemotherapy inducing, however, adverse effects. To reduce the effective dose of paclitaxel, we searched for pharmaceutics which could potentiate its therapeutic effect. We screened a chemical library and selected Carba1, a carbazole, which exerts synergistic cytotoxic effects on tumor cells grown in vitro, when co-administrated with a low dose of paclitaxel. Carba1 targets the colchicine binding-site of tubulin and is a microtubule-destabilizing agent. Catastrophe induction by Carba1 promotes paclitaxel binding to microtubule ends, providing a mechanistic explanation of the observed synergy. The synergistic effect of Carba1 with paclitaxel on tumor cell viability was also observed in vivo in xenografted mice. Thus, a new mechanism favoring paclitaxel binding to dynamic microtubules can be transposed to in vivo mouse cancer treatments, paving the way for new therapeutic strategies combining low doses of microtubule targeting agents with opposite mechanisms of action.

Data presented in this article are associated with the research article "Identification of antiviral compounds against equid herpesvirus-1 using real-time cell assay screening: efficacy of decitabine and valganciclovir alone and in combination" [1]. These data correspond to the in vitro screening of 2,891 potential antiviral compounds against equid herpesvirus-1 (EHV-1) based on impedance measurements using the xCELLigence® RTCA MP System. This dataset includes compounds from three different libraries: i) 1,199 compounds from the Prestwick® Chemical Library, which contains mostly US Food and Drug Administration approved drugs (Prestwick® Chemical, Illkirch, France); ii) 1,651 compounds from the Centre d'Etudes et de Recherche sur le Médicament de Normandie (CERMN, Caen, France); iii) 41 compounds (called herein in-house antiviral library) selected for their effects against different human viruses. Compounds effective against EHV-1 were selected using the area under normalised curves (AUCn) and the time required for the Cell Index to decrease by 50% after virus infection (CIT50). The full dataset from the screen is made publicly available for further analyses.

The mite Varroa destructor is an ectoparasite and has been identified as a major cause of worldwide honey bee colony losses. The use of yearly treatments for the control of varroosis is the most common answer to prevent collapses of honey bee colonies due to the mite. However, the number of effective acaricides is small and the mite tends to become resistant to these few active molecules. In this study, we have been looking for a new original varroacide treatment inhibiting selectively Varroa destructor AChE (vdAChE) with respect to Apis mellifera AChE (amAChE). To do this an original drug design methodology was used applying virtual screening of the CERMN chemolibrary, starting from a vdAChE homology sequence model. By combining the in silico screening with in vitro experiments, two promising compounds were found. In vitro tests of AChE inhibition for both species have confirmed good selectivity toward the mite vdAChE. Moreover, an in vivo protocol was performed and highlighted a varroacide activity without acute consequences on honey bee survival. The two compounds discovered have the potential to become new drug leads for the development of new treatments against the mite varroa. The method described here clearly shows the potential of a drug-design approach to develop new solutions to safeguard honey bee health.

Pro-survival stress-inducible chaperone HSP110 is the only HSP for which a mutation has been found in a cancer. Multicenter clinical studies demonstrated a direct association between HSP110 inactivating mutation presence and excellent prognosis in colorectal cancer patients. Here, we have combined crystallographic studies on human HSP110 and in silico modeling to identify HSP110 inhibitors that could be used in colorectal cancer therapy. Two molecules (foldamers 33 and 52), binding to the same cleft of HSP110 nucleotide-binding domain, were selected from a chemical library (by co-immunoprecipitation, AlphaScreening, Interference-Biolayer, Duo-link). These molecules block HSP110 chaperone anti-aggregation activity and HSP110 association to its client protein STAT3, thereby inhibiting STAT3 phosphorylation and colorectal cancer cell growth. These effects were strongly decreased in HSP110 knockdown cells. Foldamer's 33 ability to inhibit tumor growth was confirmed in two colorectal cancer animal models. Although tumor cell death (apoptosis) was noted after treatment of the animals with foldamer 33, no apparent toxicity was observed, notably in epithelial cells from intestinal crypts. Taken together, we identified the first HSP110 inhibitor, a possible drug-candidate for colorectal cancer patients whose unfavorable outcome is associated to HSP110.

Edema factor (EF), a toxin of Bacillus anthracis, is activated by calmodulin (CaM). The EF/CAM interaction induces the appearance of a site catalyzing the production of cyclic AMP (cAMP), through the folding of a disordered switch. Previous studies (Laine, 2010) have shown that thiophen ureidoacids inhibit the cAMP production, but their binding site is not precisely known. These inhibitors were discovered by targeting in silico the switch, and, interestingly, similar compounds were shown to target the switch region of bacterial RNAP (Sahner, 2013; Fruth, 2014). Beside, interactions between adefovir compound and EF have been extensively studied (Shen, 2004; Česnek, 2018). An X-ray crystallographic structure of the EF/adefovir complex displays the compound bound into the catalytic site in the presence of a Rubidium ion. The disordered switch observed in the inactive EF and the partial knowledge of the interactions between the protein and these inhibitors open a wide range of possibilities for the interactions. In the present work, we use various experimental approaches, biochemical assays and NMR, as well as molecular modeling to investigate these interactions. Česnek et al. Analogues as Potent and Selective Inhibitors of Adenylate Cyclases from Bordetella pertussis and Bacillus anthracis. ChemMedChem 2018. Fruth et al. Binding mode characterization of novel RNA polymerase inhibitors using a combined biochemical and NMR approach. ACS Chem Biol 2014. Laine et al. Use of allostery to identify inhibitors of calmodulin induced activation of Bacillus anthracis edema factor. Proc Natl Acad Sci USA 2010. Sahner et al. Novel small molecule inhibitors targeting the "switch region" of bacterial RNAP: structure-based optimization of a virtual screening hit. Eur J Med Chem 2013. Shen et al. Selective inhibition of anthrax edema factor by adefovir, a drug for chronic hepatitis B virus infection.Proc Natl Acad Sci USA 2004.

Protein-protein interactions are attractive targets because they control numerous cellular processes. In oncology, apoptosis regulating Bcl-2 family proteins are of particular interest. Apoptotic cell death is controlled via PPIs between the anti-apoptotic proteins hydrophobic groove and the pro-apoptotic proteins BH3 domain. In ovarian carcinoma, it has been previously demonstrated that Bcl-xL and Mcl-1 cooperate to protect tumor cells against apoptosis. Moreover, Mcl-1 is a key regulator of cancer cell survival and is a known resistance factor to Bcl-2/Bcl-xL pharmacological inhibitors making it an attractive therapeutic target. Here, using a structure-guided design from the oligopyridine lead Pyridoclax based on Noxa/Mcl-1 interaction we identified a new derivative, active at lower concentration as compared to Pyridoclax. This new derivative selectively binds to the Mcl-1 hydrophobic groove and releases Bak and Bim from Mcl-1 to induce cell death and sensitize cancer cells to Bcl-2/Bcl-xL targeting strategies.

Abstract Ovarian cancer is the leading cause of death from gynecological malignancies worldwide. Although the patients are initially quite sensitive to the taxane and platinum-based first-line chemotherapy, most of them relapse and develop chemoresistance. Defects in apoptosis regulation in ovarian cancer allow the cancer cells to evade cell death and contribute to chemoresistance. Mcl-1 is an anti-apoptotic member of the Bcl-2 proteins family and its amplifıcation is one of the most frequent genetic aberrations found in human cancers. Its expression is at the origin of the acquired resistance to chemotherapy and to Bcl-2 and Bcl-xL inhibitors. In ovarian cancers, we previously demonstrated that Bcl-xL and Mcl-1 cooperate to prevent cancer cells from undergoing apoptotic cell death. Their concomitant inhibitions lead to massive apoptosis even in absence of chemotherapy. Moreover, in some cases, Mcl-1 inhibition is itself able to lead to apoptosis. If clinically relevant pharmacologic inhibition of Bcl-xL is available using ABT-263, selective direct inhibition of Mcl-1 remains problematic. In this context, our teams have designed and synthesized small compounds based on a pyridyl scaffold, named oligopyridines, which potentially target the Mcl-1 hydrophobic binding pocket. We demonstrated that the lead of the first generation of oligopyridines, named Pyridoclax, interacts directly with Mcl-1, releases its pro-apoptotic partners Bim and Bak and induces massive apoptosis at 25 µM concentration in combination with anti-Bcl-xL strategies in chemoresistant ovarian cancer cell lines (Gloaguen et al., J Med Chem 2015). In the present study, we investigated the antitumor activity of Pyridoclax hydrochloride in three subcutaneous xenograft models derived from the injection of chemoresistant ovarian cancer cell lines. Different routes of Pyridoclax hydrochloride administration were tested and its antitumor effect was analyzed at different doses as single agent or in combination with ABT-263. This study highlighted an effective antitumor activity of 20mg/kg of Pyridoclax administered intravenously as single agent in two of three xenograft models without side effects. In order to improve its biological activity, we evaluated the cytotoxic effects of a second generation of oligopyridines derived from the Pyridoclax. This allowed us to identify the MR31367, one of the most potent oligopyridines that shows a stronger pro-apoptotic activity in association with to Bcl-xL-targeting strategies in ovarian cancer cell lines. Further characterization showed that this derivative binds Mcl-1 and release Bim and Bak from it, leading to Bak-mediated apoptosis. Overall, these results open up interesting perspectives for the clinical use of Mcl-1 inhibitors as single agent or in combination with anticancer drugs to improve the clinical management of ovarian cancers. Citation Format: Siham Hedir, Louis-Bastien Weiswald, Marcella De Giorgi, Jade Fogha, Martina De Pascale, Emilie Brotin, Bogdan Marekha, Peggy Suzanne, Fabien Gautier, Philippe Juin, Laetitia Ligat, Frédéric Lopez, Rémi Legay, Ronan Bureau, Sylvain Rault, Jana Sopkova-de Oliveira Santos, Anne-Sophie Voisin-Chiret, Laurent Poulain. Pyridoclax and its derivatives from oligopyridine family directly inhibit Mcl-1 and exert potent antitumor effects on ovarian cancer in vitro and in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3996.

Introduction : Trois alphaherpesvirus (HVE-1, -3, et -4) sont decrits comme infectant les chevaux. L’herpesvirus equin 1 (HVE-1), nomme virus abortif, est le plus pathogene d’entre eux. Trois formes de la maladie sont classiquement decrites : respiratoire, abortive et nerveuse. L’HVE-4, nomme virus de la rhinopneumonie, provoque principalement des symptomes respiratoires et occasionnellement des avortements. L’HVE-3 est quant a lui responsable de l'exantheme coital equin. L’infection des chevaux par ces virus provoque de lourdes pertes economiques pour la filiere equine (exemple de l’epizootie d’ampleur observee depuis mars 2018) ce qui justifie une surveillance et une prophylaxie. Actuellement, aucune molecule antivirale ne dispose d'une autorisation de mise sur le marche pour les equides, malgre des besoins critiques justifiant le developpement ou l'adaptation de medicaments efficaces contre les virus equins. Objectifs : 1) Etudier l'efficacite du systeme xCELLigence pour suivre l’infection cellulaire par l’HVE-1, l’HVE-4 et l’HVE-3 ; 2) Evaluer l'efficacite de l'aciclovir (ACV) et du ganciclovir (GCV) contre les HVEs ; 3) Etudier la capacite du systeme xCELLigence® pour le criblage d’une chimiotheque de 1200 composes afin d'identifier de nouveaux antiviraux. Materiels et methodes : L’infection des cellules dermiques equines par l’HVE-1, l’HVE-4 et l’HVE-3 est suivi par impedancemetrie (xCELLigence®, ACEA), par observation microscopique en temps reel et par quantification des charges virales en PCR quantitative. Resultats : L’evolution des valeurs d’impedance (Cell Index, CI) est correlee a l’apparition et l’evolution de l’effet cytopathogene induit par les HVEs et a l’augmentation des charges virales mesurees. L’ACV et le GCV empechent la diminution d'impedance induite par l'HVE-1 d'une maniere dose-dependante et les concentrations efficaces mediane (EC50) mesurees sont de 9,88 ± 2,14 μg/ml et de 0,62 ± 0,49 μg/ml, respectivement. Les EC50 de l'ACV et du GCV contre l’HVE-4 sont de 17,38 ± 5,95 μg/ml et de 2,79 ± 0,25 μg/ml, respectivement. Pour l’HVE-3, les EC50 de l'ACV et du GCV sont respectivement de 15,23 ± 2,85 μg/ml et 1,86 ± 0,46 μg/ml. Le criblage d’une premiere banque de 1200 composes a permis d'identifier plusieurs molecules ayant une activite antivirale contre l’HVE-1. Discussion-Conclusion : Cette etude confirme l'efficacite du systeme xCELLigence® pour cribler des molecules antivirales contre les alphaherpesvirus equins. Le GCV s'est avere etre plus efficace que l’ACV contre les trois herpesvirus etudies. Comite d’ethique : Non applicable Sources de financement : LABEO, IFCE (Institut Francais du Cheval et de l’Equitation, projet AMIE), Fonds Eperon (projets N87-2014, N07-2015, N07-2016, N13-2017 et N62-2017) et Region Normandie (CPER R25 P3). Conflit d’interet : Les auteurs declarent aucun conflit d‘interet.

ABSTRACT In a search for new antifungal compounds, we screened a library of 4,454 chemicals for toxicity against the human fungal pathogen Aspergillus fumigatus . We identified sr7575, a molecule that inhibits growth of the evolutionary distant fungi A. fumigatus , Cryptococcus neoformans , Candida albicans , and Saccharomyces cerevisiae but lacks acute toxicity for mammalian cells. To gain insight into the mode of inhibition, sr7575 was screened against 4,885 S. cerevisiae mutants from the systematic collection of haploid deletion strains and 977 barcoded haploid DAmP (decreased abundance by mRNA perturbation) strains in which the function of essential genes was perturbed by the introduction of a drug resistance cassette downstream of the coding sequence region. Comparisons with previously published chemogenomic screens revealed that the set of mutants conferring sensitivity to sr7575 was strikingly narrow, affecting components of the endoplasmic reticulum-associated protein degradation (ERAD) stress response and the ER membrane protein complex (EMC). ERAD-deficient mutants were hypersensitive to sr7575 in both S. cerevisiae and A. fumigatus , indicating a conserved mechanism of growth inhibition between yeast and filamentous fungi. Although the unfolded protein response (UPR) is linked to ERAD regulation, sr7575 did not trigger the UPR in A. fumigatus and UPR mutants showed no enhanced sensitivity to the compound. The data from this chemogenomic analysis demonstrate that sr7575 exerts its antifungal activity by disrupting ER protein quality control in a manner that requires ERAD intervention but bypasses the need for the canonical UPR. ER protein quality control is thus a specific vulnerability of fungal organisms that might be exploited for antifungal drug development.