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Jasmin Fisher

Publications and source records attributed to Jasmin Fisher.

4 recordsLinked to original sources

Virtual Tumors Enable Prediction of Personalized Therapeutic Combinations for Non-Small Cell Lung Cancer.

UNLABELLED: The disease burden from non-small cell lung cancer (NSCLC) adenocarcinoma is substantial, with a million new cases diagnosed globally each year and a 5-year survival rate of less than 20%. The lack of therapeutic options personalized to individual patients leads to high variation in survival. The combination of patient stratification with personalized treatment has the potential to improve outcomes; however, the variation in mutations found in patients with NSCLC adenocarcinoma makes experimentally determining treatment combinations time-consuming and expensive. In this study, we developed an interpretable mechanistic model to decipher complex signaling interplay and guide personalized therapy in NSCLC adenocarcinoma. This "virtual tumor" model encompassed key tumor-intrinsic oncogenic signaling pathways for efficiently predicting rational drug-drug and drug-radiotherapy combination therapies in NSCLC. Diverse genetic profiles were simulated for testing more than 10,000 therapeutic strategies to identify optimal approaches to overcome resistance mechanisms specific to genetic profiles and p53 status. The virtual tumor model reproduced drug additivity screens, predicted radiosensitizing genes validated in a CRISPR screen, and identified 53BP1 as a potential drug target that improved the therapeutic window during radiotherapy. A 19-gene signature derived from the virtual tumor framework stratified patients most likely to benefit from radiotherapy, which was validated using The Cancer Genome Atlas (TCGA) data. These results show the utility of virtual tumors to predict effective therapeutic combinations and present a computational resource for large-scale screening of personalized therapies to guide clinical decision-making in patients with NSCLC. SIGNIFICANCE: A computational framework that simulates thousands of personalized treatment strategies offers a scalable, cost-effective way to tailor therapies and improve outcomes for patients with genetically diverse NSCLC.

Humans↗

Computational insights into Caenorhabditis elegans vulval development.

Studies of Caenorhabditis elegans vulval development provide a paradigm for pattern formation during animal development. The fates of the six vulval precursor cells are specified by the combined action of an inductive signal that activates the EGF receptor mitogen-activated PK signaling pathway (specifying a primary fate) and a lateral signal mediated by LIN-12/Notch (specifying a secondary fate). Here we use methods devised for the engineering of complex reactive systems to model a biological system. We have chosen the visual formalism of statecharts and use it to formalize Sternberg and Horvitz's 1989 model [Sternberg, P. W. & Horvitz, H. R. (1989) Cell 58, 679-693], which forms the basis for our current understanding of the interaction between these two signaling pathways. The construction and execution of our model suggest that different levels of the inductive signal induce a temporally graded response of the EGF receptor mitogen-activated PK pathway and make explicit the importance of this temporal response. Our model also suggests the existence of an additional mechanism operating during lateral specification that prohibits neighboring vulval precursor cells from assuming the primary fate.

Animals↗

Protective autoimmunity against the enemy within: fighting glutamate toxicity.

Glutamate, a key neurotransmitter, is pivotal to CNS function. Alterations in its concentration can be dangerous, as seen for example in acute injuries of the CNS, chronic neurodegenerative disorders and mental disorders. Its homeostasis is attributed to the efficient removal of glutamate from the extracellular milieu by reuptake via local transport mechanisms. Our recent studies suggest that glutamate, either directly or indirectly, elicits a purposeful systemic T-cell-mediated immune response directed against immunodominant self-antigens that reside at the site of glutamate-induced damage. We suggest that the harnessed autoimmunity (which we have termed 'protective autoimmunity') helps the resident microglia in their dual function as antigen-presenting cells (serving the immune system) and as cells that clear the damaged site of potentially harmful material (serving the nervous system). The interplay between glutamate and an adaptive immune response illustrates the bidirectional dialog between the immune and nervous systems, under both physiological and pathological conditions. These results point to the possible development of a therapeutic vaccination with self-antigens, or with antigens cross-reactive with self-antigens, as a way to augment autoimmunity without inducing an autoimmune disease, thus providing a safe method of limiting degeneration. This approach, which boosts a physiological mechanism for the regulation of glutamate, and possibly also that of other self-compounds, might prove to be a feasible strategy for therapeutic protection against glutamate-associated neurodegenerative or mental disorders.

Animals↗

Neuroprotection by T-cells depends on their subtype and activation state.

This study analyzes how the antigen specificity, the subtype, and the activation state of T cells modulate their recently discovered neuroprotective potential. We assessed the prevention from neuronal damage in organotypic entorhinal-hippocampal slice cultures after co-culture with Th1 and Th2 cells either specific for myelin basic protein (MBP) or ovalbumin (OVA). We found that MBP-specific Th2 cells were the most effective in preventing central nervous system (CNS) tissue from secondary injury. This neuroprotective T cell effect appears to be mediated by soluble factors. After stimulation with phorbol myristate acetate and ionomycin, all T cells were most effective in preventing neuronal death. Our data show that the T cell subtype and activation state are important features in determining the neuroprotective potential of these cells.

Animals↗