Biology subjects

Stein, K.

Publications and source records attributed to Stein, K..

5 recordsLinked to original sources

bioRxiv2026

SERPINB13 is a prognostic biomarker for LUSC associated with an immune-inflamed tumor phenotype and modulated by immune cells

Non-small cell lung cancer (NSCLC) is the most common form of lung cancer accounting for most cancer-related deaths worldwide. Despite substantial recent advances in targeted therapies and immunotherapy, the prognosis for advanced-stage disease remains comparably poor, which is why the identification of novel molecular biomarkers as well as therapeutic targets influencing tumor development, progression, and metastasis remain important. This study focusses on SERPINB13, a serine-protease inhibitor expressed in selected tissues that is dysregulated in several tumor entities. However, its role in NSCLC still remains largely unclear. We analyzed SERPINB13 transcription in a cohort of non-small cell lung cancer (NSCLC) cases including both lung squamous cell carcinoma (LUSC) and lung adenocarcinoma (LUAD) by transcriptome profiling. Epigenetic modifications were assessed via Methylation BeadChips. Additionally, SERPINB13 protein expression was assessed by immunohistochemistry (IHC) in an independent cohort of NSCLC comprising 126 LUSC patients. Correlation analyses were performed to associate SERPINB13 expression with key clinico-pathological parameters, including overall survival and extent of tumor-infiltrating immune cells. To functionally investigate the regulatory influence of peripheral blood mononuclear cells (PBMCs) on SERPINB13 expression in LUSC tumor cells in vitro, we utilized the SERPINB13-expressing LUSC cell line LUDLU-1. Here, gene transcription was analyzed by quantitative real-time PCR (RT-qPCR), confirmed by Western blot on the protein level. Transcriptome analysis revealed a significant upregulation of SERPINB13 in lung squamous cell carcinoma (LUSC) compared to lung adenocarcinoma (LUAD), highlighting a subtype-specific expression pattern. This differential expression was further associated with a distinct epigenetic DNA methylation signature at the SERPINB13 loci in LUSC, suggesting transcriptional regulation via hypomethylation. IHC analysis demonstrated that high SERPINB13 protein expression is significantly associated with prolonged overall survival in LUSC. Notably, SERPINB13 expression was enriched in immune-inflamed ("hot") tumors, characterized by elevated infiltrating lymphocytes and immune activation. Mechanistically, co-culture experiments with PBMCs induced SERPINB13 expression in a LUSC cell line in a dose- and time-dependent manner in the absence of direct cell contact. This suggests that soluble factors secreted by immune cells might play a key role in regulating SERPINB13 expression in the tumor microenvironment. Taken together, SERPINB13 is a novel prognostic indicator in LUSC that is modulated by Immune cells. Further studies are necessary to decipher the crosstalk of Immune cells on the Serpin B13 expressing tumor cells in depth, with regard to a possible interventional strategy. immunomodulatory potential strategies and personalized therapeutic approaches in NSCLC.

pathology↗

bioRxiv2026

Cis-regulatory elements orchestrate phase-specific effector gene expression in Ustilago maydis

Plant pathogenic fungi secrete small proteins, termed effectors, to reprogram host metabolism and suppress immune responses during infection. Although transcriptional waves of effector expression have been described in several pathosystems, the cis-regulatory elements encoding infection-stage specificity remain largely unknown. Here, we investigate the temporal regulation of effector genes in the biotrophic smut fungus Ustilago maydis, a model organism for fungal plant pathogenesis. By integrating transcriptome reanalysis with comparative promoter motif enrichment across biotrophic fungi, we identify distinct promoter motifs associated with defined infection phases. In U. maydis, three candidate cis-regulatory elements correlate with early, proliferative, and late infection stages, respectively. Positional enrichment relative to transcription start sites supports their regulatory relevance. Functional promoter mutagenesis demonstrates that the early-phase motif GTGGG significantly contributes to effector gene expression in planta and is sufficient to drive stage-restricted gene expression in synthetic minimal promoters. Collectively, our findings demonstrate that temporal deployment of the effector repertoire is at least partially encoded at the promoter level. The identified cis-regulatory elements provide a framework for dissecting transcriptional control during biotrophic infection and offer tools for infection-stage-specific gene expression in synthetic biology applications.

microbiology↗

bioRxiv2025

JNK integrates immune and stress signals to balance apoptosis and proliferation in airway progenitors

Chronic inflammation disrupts epithelial regeneration, yet how immune signaling reprograms progenitor fate remains unclear. Using the Drosophila airway as a model of epithelial remodeling, we identify the c-Jun N-terminal kinase (JNK) pathway as a central integrator of immune and stress cues that balances apoptosis and compensatory proliferation in airway progenitors. Persistent activation of the innate immune IMD pathway induces simultaneous cell death and proliferation through a non-canonical route that bypasses NF-{kappa}B/Relish and instead engages JNK. Downstream, distinct transcriptional modules orchestrate these divergent fates: Foxo and AP-1 drive apoptosis, whereas the ETS factor Ets21C mediates proliferation. Genetic inhibition of JNK or its effectors restores progenitor homeostasis, while constitutive activation recapitulates inflammation-induced tissue remodeling. These responses are cell-autonomous, revealing that airway progenitors actively interpret immune and stress signals to determine their fate. Collectively, our findings uncover a modular signaling architecture that links inflammation to regeneration and highlight conserved JNK-dependent transcriptional programs as potential therapeutic targets to prevent progenitor exhaustion in chronic airway disease.

cell biology↗

bioRxiv2020

A comprehensive framework for handling location error in animal tracking data

Animal tracking data are being collected more frequently, in greater detail, and on smaller taxa than ever before. These data hold the promise to increase the relevance of animal movement for understanding ecological processes, but this potential will only be fully realized if their accompanying location error is properly addressed. Historically, coarsely-sampled movement data have proved invaluable for understanding large scale processes (e.g., home range, habitat selection, etc.), but modern fine-scale data promise to unlock far more ecological information. While GPS location error can often be ignored in coarsely sampled data, fine-scale data require more care, and tools to do this have not kept pace. Current approaches to dealing with location error largely fall into two categories--either discarding the least accurate location estimates prior to analysis or simultaneously fitting movement and error parameters in a hidden-state model. In some cases these approaches can provide a level of correction, but they have known limitations, and in some cases they can be worse than doing nothing. Here, we provide a general framework to account for location error in the analysis of triangulated and trilatcralizcd animal tracking data, which includes GPS, Argos Doppler-shift, triangulated VHF, trilatcralized acoustic and cellular location data. We apply our error-modelselection framework to 190 GPS, cellular, and acoustic devices representing 27 models from 14 manufacturers. Collectively, these devices were used to track a wide range of taxa comprising birds, fish, reptiles, and mammals of different sizes and with different behaviors, in urban, suburban, and wild settings. In almost half of the tested device models, error-model selection was necessary to obtain the best performing error model, and in almost a quarter of tested device models, the reported DOP values were actually misinformative. Then, using empirical tracking data from multiple species, we provide an overview of modern, error-informed movement analyses, including continuous-time path reconstruction, home-range distribution, home-range overlap, speed, and distance estimation. Adding to these techniques, we introduce new error-informed estimators for outlier detection and autocorrelation visualization. Because error-induced biases depend on many factors--sampling schedule, movement characteristics, tracking device, habitat, etc.--differential bias can easily confound biological inference and lead researchers to draw false conclusions. We demonstrate how error-informed analyses on calibrated tracking data can provide more accurate estimates are that are insensitive to location error, and allow researchers to use all of their data.

ecology↗

bioRxiv2020

Inhibition of DNAJ-HSP70 interaction improves strength in muscular dystrophy

Dominant mutations in the HSP70 co-chaperone DNAJB6 cause a late onset muscle disease termed limb girdle muscular dystrophy type 1D (LGMD1D), which is characterized by protein aggregation and vacuolar myopathology. Disease mutations reside within the G/F domain of DNAJB6, but the molecular mechanisms underlying dysfunction are not well understood. Using yeast, cell culture, and mouse models of LGMD1D, we find that the toxicity associated with disease-associated DNAJB6 requires its interaction with HSP70, and that abrogating this interaction genetically or with small molecules is protective. In skeletal muscle, DNAJB6 localizes to the Z-disc with HSP70. Whereas HSP70 normally diffuses rapidly between the Z-disc and sarcoplasm, the rate of HSP70s diffusion in LGMD1D mouse muscle is diminished likely because it has an unusual affinity for the Z-disc and mutant DNAJB6. Treating LGMD1D mice with a small molecule inhibitor of the DNAJ-HSP70 complex re-mobilizes HSP70, improves strength and corrects myopathology. These data support a model in which LGMD1D mutations in DNAJB6 are a gain-of-function disease that is, counter-intuitively, mediated via HSP70 binding. Thus, therapeutic approaches targeting HSP70:DNAJB6 may be effective in treating this inherited muscular dystrophy.

cell biology↗