Biology subjects

Wawer, M. J.

Publications and source records attributed to Wawer, M. J..

5 recordsLinked to original sources

bioRxiv2024

The enzyme glutamate-cysteine ligase (GCL) is a target for ferroptosis induction in cancer

Despite glutathiones long-recognized role as a major cellular antioxidant and its central role in ferroptosis defense, inhibition of glutathione biosynthetic enzymes has received little attention as a target for the therapeutic induction of ferroptosis. Here, we report that small-molecule inhibition of glutamate-cysteine ligase (GCL), the rate-limiting enzyme of glutathione biosynthesis, selectively and potently kills cancer cells by ferroptosis. We further describe novel GCL inhibitors including KOJ-1 and KOJ-2, compounds with excellent cellular potency and pharmacological properties, representing valuable tools to study the biology of ferroptosis and glutathione.

cancer biology↗

bioRxiv2024

Validation of ferroptosis in canine cancer cells to enable comparative oncology and translational medicine

Ferroptosis is a cell death mechanism that has attracted significant attention as a potential basis for the development of new cancer therapies. Validation of ferroptosis biology in species commonly used in translation and pre-clinical development is a necessary foundation for enabling the advancement of such ferroptosis modulating drugs. Here, we demonstrate that canine cancer cells exhibit sensitivity to a wide range of ferroptosis-inducing perturbations in a manner indistinguishable from human cancer cells, and recapitulate characteristic patterns of ferroptotic response across tumor types seen in the human setting. The foundation provided herein establishes the dog as a relevant efficacy and toxicology model for ferroptosis and creates new opportunities to leverage the canine comparative oncology paradigm to accelerate the development of ferroptosis-inducing drugs for human cancer patients.

cancer biology↗

bioRxiv2024

Commonly used organoid culture media prevent ferroptosis

Organoids enable the recreation of organ physiology in vitro and serve as powerful models for biology in basic life science research and drug discovery and development. However, organoid culture requires complex media formulations that include antioxidants, potentially confounding experimental results sensitive to such conditions. Here we report that the growth conditions used commonly to generate organoid models inhibit ferroptosis, an iron-dependent form of lipid peroxidative cell death with relevance to human disease, thus rendering such models incompatible with ferroptosis research. We identify medium components that diminish or eliminate ferroptosis sensitivity and outline strategies for avoiding anti-ferroptotic culture conditions in organoid and other cell culture applications. These findings provide a roadmap for adapting organoid models for the study of ferroptosis and leveraging their strengths for advancing ferroptosis-modulating therapeutics.

cancer biology↗

bioRxiv2022

Mapping the landscape of genetic dependencies in chordoma

Identifying the spectrum of genes required for cancer cell survival can reveal essential cancer circuitry and therapeutic targets, but such a map remains incomplete for many cancer types. We applied genome-scale CRISPR-Cas9 loss-of-function screens to map the landscape of selectively essential genes in chordoma, a bone cancer with few validated targets. This approach confirmed a known chordoma dependency, TBXT (T; brachyury), and identified a range of additional dependencies, including PTPN11, ADAR, PRKRA, LUC7L2, SRRM2, SLC2A1, SLC7A5, FANCM, and THAP1. CDK6, SOX9, and EGFR, genes previously implicated in chordoma biology, were also recovered. We found genomic and transcriptomic features that predict specific dependencies, including interferon-stimulated gene expression, which correlates with ADAR dependence and is elevated in chordoma. Validating the therapeutic relevance of dependencies, small-molecule inhibitors of SHP2, encoded by PTPN11, had potent preclinical efficacy against chordoma. Our results generate an emerging map of chordoma dependencies to enable biological and therapeutic hypotheses.

cancer biology↗

bioRxiv2022

Reference compounds for characterizing cellular injury in high-content cellular morphology assays

Robust, generalizable approaches to identify compounds efficiently with undesirable mechanisms of action in complex cellular assays remain elusive. Such a process would be useful for hit triage during high-throughput screening and, ultimately, predictive toxicology during drug development. We generated cell painting and cellular health profiles for 218 prototypical cytotoxic and nuisance compounds in U-2 OS cells in a concentration-response format. A diversity of compounds causing cellular damage produced bioactive cell painting morphologies, including cytoskeletal poisons, genotoxins, nonspecific electrophiles, and redox-active compounds. Further, we show that lower quality lysine acetyltransferase inhibitors and nonspecific electrophiles can be distinguished from more selective counterparts. We propose that the purposeful inclusion of cytotoxic and nuisance reference compounds such as those profiled in this Resource will help with assay optimization and compound prioritization in complex cellular assays like cell painting.

pharmacology and toxicology↗