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Stafford, G. A.

Publications and source records attributed to Stafford, G. A..

3 recordsLinked to original sources

A Genomically and Clinically Annotated Patient Derived Xenograft (PDX) Resource for Preclinical Research in Non-Small Cell Lung Cancer

Patient-derived xenograft models (PDXs) are an effective preclinical in vivo platform for testing the efficacy of novel drug and drug combinations for cancer therapeutics. Here we describe a repository of 79 genomically and clinically annotated lung cancer PDXs available from The Jackson Laboratory that have been extensively characterized for histopathological features, mutational profiles, gene expression, and copy number aberrations. Most of the PDXs are models of non-small cell lung cancer (NSCLC), including 37 lung adenocarcinoma (LUAD) and 33 lung squamous cell carcinoma (LUSC) models. Other lung cancer models in the repository include four small cell carcinomas, two large cell neuroendocrine carcinomas, two adenosquamous carcinomas, and one pleomorphic carcinoma. Models with both de novo and acquired resistance to targeted therapies with tyrosine kinase inhibitors are available in the collection. The genomic profiles of the LUAD and LUSC PDX models are consistent with those observed in patient tumors of the same tumor type from The Cancer Genome Atlas (TCGA) and to previously characterized gene expression-based molecular subtypes. Clinically relevant mutations identified in the original patient tumors were confirmed in engrafted tumors. Treatment studies performed for a subset of the models recapitulated the responses expected based on the observed genomic profiles. SignificanceThe collection of lung cancer Patient Derived Xenograft (PDX) models maintained at The Jackson Laboratory retain both the histologic features and treatment-relevant genomic alterations observed in the originating patient tumors and show expected responses to treatment with standard-of-care agents. The models serve as a valuable preclinical platform for translational cancer research. Information and data for the models are freely available from the Mouse Models of Human Cancer database (MMHCdb, http://tumor.informatics.jax.org/mtbwi/pdxSearch.do).

cancer biology↗

Augmented glucose dependency of autoreactive B cells provides a treatment target forlupus

Heightened glycolysis is inherent to immune/inflammatory disorders, but little is known of its role in the pathogenesis of systemic lupus erythematosus (lupus). Here, we profile key autoimmune populations in acute and chronic lupus-prone models and their response to glycolytic inhibition. We demonstrate that glycolysis is specifically required for autoreactive germinal center B cells (GCB), but not for T follicular helper cells (Tfh) to survive. This augmented reliance on glucose oxidation to maintain ATP production in pathogenic GCB renders them highly susceptible to oxidative stress-induced apoptosis triggered by glycolysis blockade via 2-deoxyglucose (2DG). We show that 2DG can preferentially reduce GCB in lupus-prone mice, while sparing other autoreactive populations, including Tfh, but still significantly improving lifespan and kidney function. Furthermore, the subset of GCB expressing B-cell maturation antigen (BCMA) exhibits an exaggerated dependence on glycolysis to sustain their growth. Depletion of these cells with a proliferation-inducing ligand-based CAR T-cells leads to greatly prolonged lifespan of mice with severe autoimmune activation. These results reveal that glycolysis dependent GCB, especially those expressing BCMA, are key lupus mediators and highlight that they can be selectively targeted to improve disease outcomes for lupus patients.

immunology↗

Genes adapt to outsmart gene targeting strategies in mutant mouse strains by skipping exons to reinitiate transcription and translation

Gene disruption in mouse embryonic stem cells or zygotes is a conventional genetics approach to identify gene function in vivo. However, because different gene-disruption strategies use different mechanisms to disrupt genes, the strategies can result in diverse phenotypes in the resulting mouse model. To determine whether different gene-disruption strategies affect the phenotype of resulting mutant mice, we characterized Rhbdf1 mouse mutant strains generated by three commonly used strategies--definitive-null, targeted knockout (KO)-first, and CRISPR/Cas9. We find that Rhbdf1 responds differently to distinct KO strategies, for example, by skipping exons and reinitiating translation to potentially yield gain-of-function alleles rather than the expected null or severe hypomorphic alleles. Our analysis also revealed that at least 4% of mice generated using the KO-first strategy show conflicting phenotypes, suggesting that exon skipping is a widespread phenomenon occurring across the genome. Additionally, our study emphasizes that at least 35% of mouse and 45% of human protein-coding genes could be predisposed to targeted KO-first- and CRISPR/Cas9-mediated unexpected translation. Our findings have significant implications for the application of genome editing in both basic research and clinical practice.

genetics↗