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Biology subjects

Berger, R.

Publications and source records attributed to Berger, R..

5 recordsLinked to original sources

Epithelial mesenchymal transition initiates precancer states in BRCA1 mutation carriers

Epithelial-to-mesenchymal transition (EMT) is activated to equip cells with the capacity to adapt to and escape hostile conditions. While EMT is required for cancer progression, its role in breast cancer initiation remains elusive. Given the basal-like phenotype of breast cancers arising in female carriers of germline BRCA1 pathogenic variants (BRCA1 carriers), we hypothesized that enhanced EMT susceptibility underlies precancerous initiation in mammary epithelium. Perturbation of patient-derived normal mammary organoids from BRCA1 carriers and non-carriers with inflammatory cytokines induced copy number variations (CNV) and the acquisition of oncogenic mutations in both groups. However, in organoids derived from BRCA1 carriers, cytokine exposure induced morphological, transcriptomic, and functional EMT, accompanied by a transition to basal-like phenotype. Concomitant DNA damage accumulation in organoids from BRCA1-carriers demonstrated PARP inhibitor sensitivity. EMT-primed states were identified in a subpopulation of normal mammary epithelium from BRCA1 carriers. We demonstrate the utility of patient-derived normal BRCA1 heterozygous mammary organoids to reveal a plastic, high-risk epithelial state that is associated with a transient, targetable vulnerability.

cancer biology↗

Macrophages inhibit Coxiella burnetii by the ACOD1-itaconate pathway for containment of Q fever

Infection with the intracellular bacterium Coxiella (C.) burnetii can cause chronic Q fever with severe complications and limited treatment options. Here, we identify the enzyme cis- aconitate decarboxylase 1 (ACOD1 or IRG1) and its product itaconate as protective host immune pathway in Q fever. Infection of mice with C. burnetii induced expression of several anti-microbial candidate genes, including Acod1. In macrophages, Acod1 was essential for restricting C. burnetii replication, while other antimicrobial pathways were dispensable. Intratracheal or intraperitoneal infection of Acod1-/- mice caused increased C. burnetii burden, significant weight loss and stronger inflammatory gene expression. Exogenously added itaconate restored pathogen control in Acod1-/- mouse macrophages and blocked replication in human macrophages. In axenic cultures, itaconate directly inhibited growth of C. burnetii. Finally, treatment of infected Acod1-/-mice with itaconate efficiently reduced the tissue pathogen load. Thus, ACOD1-derived itaconate is a key factor in the macrophage-mediated defense against C. burnetii and may be exploited for novel therapeutic approaches in chronic Q fever.

immunology↗

Clinically oriented prediction of patient response to targeted and immunotherapies from the tumor transcriptome

BackgroundPrecision oncology is gradually advancing into mainstream clinical practice, demonstrating significant survival benefits. However, eligibility and response rates remain limited in many cases, calling for better predictive biomarkers. MethodsWe present ENLIGHT, a transcriptomics-based computational approach that identifies clinically relevant genetic interactions and uses them to predict a patients response to a variety of therapies in multiple cancer types, without training on previous treatment response data. We study ENLIGHT in two translationally oriented scenarios: Personalized Oncology (PO), aimed at prioritizing treatments for a single patient, and Clinical Trial Design (CTD), selecting the most likely responders in a patient cohort. FindingsEvaluating ENLIGHTs performance on 21 blinded clinical trial datasets in the PO setting, we show that it can effectively predict a patients treatment response across multiple therapies and cancer types. Its prediction accuracy is better than previously published transcriptomics-based signatures and is comparable to that of supervised predictors developed for specific indications and drugs. In combination with the IFN-{gamma}signature, ENLIGHT achieves an odds ratio larger than 4 in predicting response to immune checkpoint therapy. In the CTD scenario, ENLIGHT can potentially enhance clinical trial success for immunotherapies and other monoclonal antibodies by excluding non-responders, while overall achieving more than 90% of the response rate attainable under an optimal exclusion strategy. ConclusionENLIGHT demonstrably enhances the ability to predict therapeutic response across multiple cancer types from the bulk tumor transcriptome. FundingThis research was supported in part by the Intramural Research Program, NIH and by the Israeli Innovation Authority.

bioinformatics↗

Divergent epigenetic profiles from two differentially impacted wild populationsof estuarine cordgrass (Sporobolus alterniflorus)

The effects of urbanization on watershed ecosystems present critical challenges to modern survival. Organisms in urbanized areas experience high rates of evolutionary change, but genetic adaptation alone cannot mitigate the rapid and severe effects of urbanization on biodiversity. Highly resilient, foundation species are key to maintaining an ecosystems integrity in the face of urban stressors. However, the rapid collapse and disappearance of watershed ecosystems calls into question the extent to which we can rely on such species for their services. Our research investigates the molecular mechanisms by which the foundation ecosystems provider, Sporobolus alterniflorus, adapts to life in an urbanized environment. To elucidate these mechanisms, we quantified changes in global DNA methylation (% 5-mC) as a result of acute heat stress. Specimens from two differentially impacted populations across an urban to suburban geographical transect formed the basis of this study. These two populations of Sporobolus alterniflora exhibit inverse global DNA methylation patterns when exposed to the same acute heat stress. Our findings suggest that epigenetic mechanisms, such as DNA methylation, control rapid and transient adaptation, in the form of differential stress responses, to distinct environment challenges. Highlights for manuscript submissionO_LI{blacksquare} estuarine grasses native to the Bronx River, NY face stresses associated with low dissolved oxygen and urbanization C_LIO_LI{blacksquare} differentially impacted populations of estuarine grasses exhibit inverse global DNA methylation profiles in response to acute heat stress C_LIO_LI{blacksquare} DNA methylation may represent a mechanism by which plants transiently respond to environmental stressors, and this may represent a form of rapid adaptive evolution C_LIO_LI{blacksquare} stress priming by transgenerational epigenetic modification may enhance fitness in grasses native to the heavily impacted Bronx River estuary C_LI

plant biology↗

Whole exome precision oncology targeting synthetic lethal vulnerabilities across the tumor transcriptome

Precision oncology has made significant advances in the last few years, mainly by targeting actionable mutations in cancer driver genes. However, the proportion of patients whose tumors can be targeted therapeutically remains limited. Recent studies have begun to explore the benefit of analyzing tumor transcriptomics data to guide patient treatment, raising the need for new approaches for systematically accomplishing that. Here we show that computationally derived genetic interactions can successfully predict patient response. Assembling a broad repertoire of 32 datasets spanning more than 1,500 patients and including both tumor transcriptomics and response data, we predicted the response in 17 out of 21 targeted and 8 out of 11 checkpoint therapy datasets across 8 different cancer types with considerable accuracy, without ever training on these datasets. Analyzing the recently published multi-arm WINTHER trial, we show that the fraction of patients benefitting from transcriptomic-based treatments could potentially be markedly increased from 15% to about 85% by targeting synthetic lethal vulnerabilities in their tumors. In summary, this is the first computational approach to obtain considerable predictive performance across many different targeted and immunotherapy datasets, providing a promising new way for guiding cancer treatment based on the tumor transcriptomics of cancer patients.

cancer biology↗