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Biology subjects

Suzanne, P.

Publications and source records attributed to Suzanne, P..

4 recordsLinked to original sources

Integrative in silico and experimental identification of non-covalent UBE2N inhibitors enhancing PARP inhibitor sensitivity

UBE2N, an E2 ubiquitin-conjugating enzyme, has emerged as a compelling therapeutic target in oncology due to its critical roles in DNA damage repair and NF-{kappa}B signalling. While covalent inhibitors have shown preclinical promise, non-covalent inhibitors offer potential advantages in terms of 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 a home library of [~]19,000 compounds targeting both the ubiquitin-binding and cofactor interfaces of UBE2N, we identified 22 candidates suitable for biological evaluation. Among these, two compounds, CERMN-2 and CERMN-16, emerged 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. CERMN-2, identified through docking, 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 leads for the development of selective, non-natural, non-covalent UBE2N inhibitors. These results provide new insights into UBE2N inhibition and support further investigation of their mechanisms of action and therapeutic potential in combination cancer therapies. HIGHLIGHTSO_LIDual in silico screening (docking and 3D pharmacophore) identified new non-covalent UBE2N inhibitor candidates. C_LIO_LITwo compounds, CERMN-2 and CERMN-16, displayed synergistic activity with Olaparib in ovarian cancer cells. C_LIO_LIMD simulations revealed distinct, site-specific binding modes for both compounds. C_LIO_LIBiophysical assays confirmed UBE2N binding for CERMN-2, identifying it as a promising non-natural, non-covalent lead. C_LI

cancer biology↗

Preventing neuropathy and improving anti-cancer chemotherapy with a carbazole-based compound

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.

cancer biology↗

Primary cilia promote EMT-induced triple-negative breast tumor heterogeneity and resistance to therapy

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. SignificanceCancer 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.

cancer biology↗

Two antagonistic microtubule targeting drugs act synergistically to kill cancer cells

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 drugs which could potentiate its therapeutic effect. We have screened a chemical library and selected Carba1, a carbazolone, 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. The Carba1-induced modulation of microtubule dynamics increases the accumulation of fluorescent paclitaxel inside microtubules, providing a mechanistic explanation of the observed synergy between Carba1 and paclitaxel. 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 accumulation in 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.

cancer biology↗