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Biology subjects

Schilling, D.

Publications and source records attributed to Schilling, D..

4 recordsLinked to original sources

Catabolism of extracellular glutathione is a driver of metastasis formation

Metastasizing cancer cells require metabolic plasticity to adapt to the microenvironment of the target organ. Analyzing metabolites in interstitial fluids, we found that the liver microenvironment is devoid of cystine but contains high concentrations of glutathione (GSH). Detailed mechanistic analysis revealed that cancer cells degrade extracellular GSH utilizing gamma-glutamyl-transferase (GGT) activity for provision of cysteine to support proliferation and prevent ferroptosis under cystine-free conditions. This was independent of system Xc- but required activity of glutamate-cysteine ligase (GCLC). GGT1 expression was associated with poor survival and upregulated in liver metastases of human breast cancer patients. Overexpression of Ggt1 in murine breast cancer cells enhanced their capacity for liver colonization and promoted lung metastases after orthotopic implantation. This identifies extracellular GSH catabolism as driver of metastasis that supports proliferation and oxidative stress resistance in metabolically challenging microenvironments.

cancer biology↗

Ferroptosis governs lymphatic vessel growth and regression

Whether, when, and how lymphatic vessels undergo cell death remains poorly understood. Here we identify ferroptosis as a physiological, cell-intrinsic regulator of the lymphatic endothelial cell survival during development and following injury, in stark contrast to the resilient organotypic blood endothelial cells. The lymphatic susceptibility to ferroptosis stems from tampered cystine/ hydropersulfide metabolism, alongside reduced glutathione availability triggered by an SH3RF3 E3 ligase mediated GPX4 degradation, and enhanced integration of polyunsaturated fatty acid enriched membrane phospholipids. Inducing ferroptosis genetically or pharmacologically elevated lymphatic lipid peroxidation, halted embryonic lymphangiogenesis and prevented post-injury lymphatic overgrowth while simultaneously shaped immune responses. Conversely, ferroptosis inhibition through saturated fatty acid supplementation led to pathological lymphatic hyperplasia. Targeting lymphatic ferroptotic mechanisms holds promise against pathological lymphatic growth in response to injury.

cell biology↗

A single-sample workflow for joint metabolomic and proteomic analysis of clinical specimens

Understanding the interplay of the proteome and the metabolome aids in understanding cellular phenotypes. To enable more robust inferences from such multi-omics analyses, combining proteomic and metabolomic datasets from the same sample provides major benefits by reducing technical variation between extracts during the pre-analytical phase, decreasing sample variation due to varying cellular content between aliquots, and limiting the required sample amount. We evaluated the advantages, practicality and feasibility of a single-sample workflow for combined proteome and metabolome analysis. In the workflow, termed MTBE-SP3, we combined a fully automated protein lysis and extraction protocol (autoSP3) with a semi-automated biphasic 75% EtOH/MTBE extraction for quantification of polar/non-polar metabolites. Additionally, we compared the resulting proteome of various biological matrices (FFPE tissue, fresh-frozen tissue, plasma, serum and cells) between autoSP3 and MTBE-SP3. Our analysis revealed that the single-sample workflow provided similar results to those obtained from autoSP3 alone, with an 85-98% overlap of proteins detected across the different biological matrices. Additionally, it provides distinct advantages by decreasing (tissue) heterogeneity by retrieving metabolomics and proteomic data from the identical biological material, and limiting the total amount of required material. Lastly, we applied MTBE-SP3 to a lung adenocarcinoma cohort of 10 patients. Integrating the metabolic and proteomic alterations between tumour and non-tumour adjacent tissue yielded consistent data independent of the method used. This revealed mitochondrial dysfunction in tumor tissue through deregulation of OGDH, SDH family enzymes and PKM. In summary, MTBE-SP3 enables the facile and confident parallel measurement of proteins and metabolites obtained from the same sample. This workflow is particularly applicable for studies with limited sample availability and offers the potential to enhance the integration of metabolomic and proteomic datasets.

cancer biology↗

A highly contiguous reference genome for Northern Bobwhite (Colinus virginianus)

Northern bobwhites (Colinus virginianus) are small quails in the New World Quail family (Odontophoridae) and are one of the most phenotypically diverse avian species. Despite extensive research on bobwhite ecology, genomic studies investigating the evolution of phenotypic diversity in this species are lacking. Here, we present a new, highly contiguous assembly for bobwhites using tissue samples from a vouchered, wild, female bird collected in Louisiana. Using Dovetail Chicago and HiC libraries with the HiRise assembly pipeline, we produced an 866.8 Mbp assembly including 1,512 scaffolds with a contig N50 of 66.8 Mbp, a scaffold L50 of four, and a BUSCO completeness score of 90.8%. This new assembly greatly improves scaffold lengths and contiguity compared to an existing draft bobwhite genome and provides an important tool for future studies of evolutionary and functional genomics in bobwhites.

genomics↗