Biology subjects

Grüner, B. M.

Publications and source records attributed to Grüner, B. M..

4 recordsLinked to original sources

bioRxiv2026

Artesunate Exploits Glutathione-Dependent Redox Vulnerability in Metastatic Lung Adenocarcinoma

Metastatic dissemination remains the principal cause of mortality in lung adenocarcinoma. To identify metabolic vulnerabilities associated with metastasis, we used cell lines with distinct metastatic abilities derived from the KrasG12D;p53KO mouse model. Building on evidence of mitochondrial dysfunction in metastasis-derived cells, we performed an in vivo screen of a focused metabolic drug library using a multiplexed DNA-barcoding platform. This approach identified artesunate as a selective inhibitor of metastatic seeding, which was validated in vivo to reduce metastatic burden while leaving primary tumor growth unaffected. Mechanistically, artesunate induced oxidative stress, characterized by reactive oxygen species and lipid peroxidation. Transcriptomic and mechanistic profiling revealed altered redox homeostasis in metastasis-derived cells. Inhibition of glutathione synthesis specifically sensitized these cells to artesunate, resulting in extensive cell death, whereas primary tumor-derived cells remained resistant. These findings identify glutathione-dependent redox homeostasis as a metabolic vulnerability in metastatic cells that can be specifically targeted using artesunate.

cancer biology↗

bioRxiv2026

Loss of the Y chromosome drives basal identity and metastatic potential via epigenetic reprogramming in pancreatic cancer

Loss of the Y chromosome (LOY) has been largely unexplored in pancreatic ductal adenocarcinoma (PDAC), and no mechanistic framework previously explained its role in tumor biology. We identify LOY as a recurrent, functionally consequential alteration affecting ~50% of male PDAC patients across two independent cohorts, with strong enrichment in advanced disease and, critically, in the basal subtype, establishing LOY as a clinically actionable biomarker. Comprehensive genomic profiling positions LOY as a distinct genetic event associated with TP53 mutations, implicating it in aggressive tumor evolution. Integrative analyses across bulk tumors, single-cell datasets and CRISPR-engineered PDAC models converge on epithelial-to-mesenchymal transition (EMT) as the dominant LOY-driven program. Y-chromosome deletion alone induces EMT transcriptional states, mesenchymal morphology and enhanced metastatic ability. Mechanistically, LOY disrupts epigenetic regulation through loss of Y-linked chromatin modifiers, reshaping DNA methylation at EMT- and basal-defining loci and reducing chemotherapy sensitivity. These findings establish LOY as a causal genetic driver of PDAC progression and a clinically accessible biomarker with direct therapeutic relevance.

cancer biology↗

bioRxiv2025

Targeted degradation of USP7 in solid cancer cells reveals disparate effects of deubiquitinase inhibition vs. acute protein depletion

Proteolysis-targeting chimeras (PROTACs) co-op the ubiquitin system for targeted protein degradation, creating opportunities to interrogate cellular functions of proteins through "chemical knockdown". However, matched pairs of protein degraders and inhibitors, that possess high specificity and chemical complementarity, for individual components of the ubiquitin system have remained scarce. This includes reagents to modulate activity and abundance of deubiquitinases (DUBs), which critically regulate ubiquitin-mediated signaling. Here, using an integrated chemical biology approach, we explored the cellular function of the DUB USP7 as a case study comparing inhibition and degradation of this DUB in melanoma and pancreatic cancer cells. Through the synthesis of a degrader library, we identified potent USP7 PROTACs for each cancer type, established BRET-based ternary complex formation and quantified degradation efficiency. USP7 degraders and their cognate inhibitor were subsequently employed to characterize treatment-induced phenotypic alterations. Proteomic and cellular analyses revealed that highly specific degradation of USP7 modulated both shared and distinct protein sets across cancer cell types, without impacting cell growth. Notably, cellular responses to USP7 degradation differed markedly from those to USP7 inhibition. Moreover, our data uncovered broad proteomic and metabolic changes induced by prolonged USP7 inhibitor treatment. Collectively, our work provides a chemical toolbox of comprehensively characterized reagents to distinguish on-target phenotypes which will aid the understanding of the role of USP7 in malignant diseases. More broadly, our data emphasize the importance of increased specificity via PROTAC-mediated degradation and the potential of this modality to distinguish catalytic from non-catalytic as well as cell-line specific functions of DUBs.

biochemistry↗

bioRxiv2019

Axon-like protrusions promote small cell lung cancer migration and metastasis

Metastasis is the main cause of death in cancer patients but remains a poorly understood process. Small cell lung cancer (SCLC) is one of the most lethal and most metastatic types of human cancer. SCLC cells normally express neuroendocrine and neuronal gene programs but accumulating evidence indicates that these cancer cells become relatively more neuronal and less neuroendocrine as they gain the ability to metastasize. Here we show that mouse and human SCLC cells in culture and in vivo can grow cellular protrusions that resemble axons. The formation of these protrusions is controlled by multiple neuronal factors implicated in axonogenesis, axon guidance, and neuroblast migration. Disruption of these axon-like protrusions impairs cell migration in culture and inhibits metastatic ability in vivo. The co-option of developmental neuronal programs is a novel molecular and cellular mechanism that contributes to the high metastatic ability of SCLC.

cancer biology↗