Ferritin H deficiency deteriorates cellular iron handling and worsens Salmonella typhimurium infection by triggering hyperinflammation

Iron is an essential nutrient for mammals as well as for pathogens. Inflammation-driven changes in systemic and cellular iron homeostasis are central for host-mediated antimicrobial strategies. Here, we studied the role of the iron storage protein ferritin H (FTH) for the control of infections with the intracellular pathogen Salmonella enterica serovar Typhimurium by macrophages. Mice lacking FTH in the myeloid lineage (LysM-Cre+/+Fthfl/fl mice) displayed impaired iron storage capacities in the tissue leukocyte compartment, increased levels of labile iron in macrophages, and an accelerated macrophage-mediated iron turnover. While under steady-state conditions, LysM-Cre+/+Fth+/+ and LysM-Cre+/+Fthfl/fl animals showed comparable susceptibility to Salmonella infection, i.v. iron supplementation drastically shortened survival of LysM-Cre+/+Fthfl/fl mice. Mechanistically, these animals displayed increased bacterial burden, which contributed to uncontrolled triggering of NF-κB and inflammasome signaling and development of cytokine storm and death. Importantly, pharmacologic inhibition of the inflammasome and IL-1β pathways reduced cytokine levels and mortality and partly restored infection control in iron-treated ferritin-deficient mice. These findings uncover incompletely characterized roles of ferritin and cellular iron turnover in myeloid cells in controlling bacterial spread and for modulating NF-κB and inflammasome-mediated cytokine activation, which may be of vital importance in iron-overloaded individuals suffering from severe infections and sepsis

Unfolding the Secrets of Small Cell Lung Cancer Progression: Novel Approaches and Insights Through Rapid Autopsies

The understanding of small cell lung cancer (SCLC) biology has increased dramatically in recent years, but the processes that allow SCLC to progress rapidly remain poorly understood. Here, we advocate the integration of rapid autopsies and preclinical models into SCLC research as a comprehensive strategy with the potential to revolutionize current treatment paradigms

Comprehensive Analysis of Transcription Factor-Based Molecular Subtypes and Their Correlation to Clinical Outcomes in Small-Cell Lung Cancer

BACKGROUND: Recent studies have reported the predictive and prognostic value of novel transcriptional factor-based molecular subtypes in small-cell lung cancer (SCLC). We conducted an in-depth analysis pairing multi-omics data with immunohistochemistry (IHC) to elucidate the underlying characteristics associated with differences in clinical outcomes between subtypes. METHODS: IHC (n = 252), target exome sequencing (n = 422), and whole transcriptome sequencing (WTS, n = 189) data generated from 427 patients (86.4% males, 13.6% females) with SCLC were comprehensively analysed. The differences in the mutation profile, gene expression profile, and inflammed signatures were analysed according to the IHC-based molecular subtype. FINDINGS: IHC-based molecular subtyping, comprised of 90 limited-disease (35.7%) and 162 extensive-disease (64.3%), revealed a high incidence of ASCL1 subtype (IHC-A, 56.3%) followed by ASCL1/NEUROD1 co-expressed (IHC-AN, 17.9%), NEUROD1 (IHC-N, 12.3%), POU2F3 (IHC-P, 9.1%), triple-negative (IHC-TN, 4.4%) subtypes. IHC-based subtype showing high concordance with WTS-based subtyping and non-negative matrix factorization (NMF) clusterization method. IHC-AN subtype resembled IHC-A (rather than IHC-N) in terms of both gene expression profiles and clinical outcomes. Favourable median overall survival was observed in IHC-A (15.2 months) compared to IHC-N (8.0 months, adjusted HR 2.3, 95% CI 1.4-3.9, p = 0.002) and IHC-P (8.3 months, adjusted HR 1.7, 95% CI 0.9-3.2, p = 0.076). Inflamed tumours made up 25% of cases (including 53% of IHC-P, 26% of IHC-A, 17% of IHC-AN, but only 11% of IHC-N). Consistent with recent findings, inflamed tumours were more likely to benefit from first-line immunotherapy treatment than non-inflamed phenotype (p = 0.002). INTERPRETATION: This study provides fundamental data, including the incidence and basic demographics of molecular subtypes of SCLC using both IHC and WTS from a comparably large, real-world Asian/non-Western patient cohort, showing high concordance with the previous NMF-based SCLC model. In addition, we revealed underlying biological pathway activities, immunogenicity, and treatment outcomes based on molecular subtype, possibly related to the difference in clinical outcomes, including immunotherapy response

Brief Report: Comprehensive Clinicogenomic Profiling of Small Cell Transformation From EGFR-Mutant NSCLC Informs Potential Therapeutic Targets

INTRODUCTION: NSCLC transformation to SCLC has been best characterized with METHODS: In this study, we conducted a single-center retrospective analysis of clinical and genomic characteristics of patients with RESULTS: A total of 34 patients were identified in our study. Median age at initial diagnosis was 58, and median time to SCLC transformation was 24.2 months. 68% were female and 82% were never smokers. 79% of patients were diagnosed as stage IV disease, and over half had brain metastases at baseline. Median overall survival of the entire cohort was 38.3 months from initial diagnoses and 12.4 months from time of SCLC transformation. Most patients harbored CONCLUSIONS: SCLC transformation is a potential treatment resistance mechanism in driver-mutant NSCLC. In our cohort of 3

Enhancing NSCLC Recurrence Prediction With PET/CT Habitat Imaging, ctDNA, and Integrative Radiogenomics-Blood Insights

While we recognize the prognostic importance of clinicopathological measures and circulating tumor DNA (ctDNA), the independent contribution of quantitative image markers to prognosis in non-small cell lung cancer (NSCLC) remains underexplored. In our multi-institutional study of 394 NSCLC patients, we utilize pre-treatment computed tomography (CT) and 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) to establish a habitat imaging framework for assessing regional heterogeneity within individual tumors. This framework identifies three PET/CT subtypes, which maintain prognostic value after adjusting for clinicopathologic risk factors including tumor volume. Additionally, these subtypes complement ctDNA in predicting disease recurrence. Radiogenomics analysis unveil the molecular underpinnings of these imaging subtypes, highlighting downregulation in interferon alpha and gamma pathways in the high-risk subtype. In summary, our study demonstrates that these habitat imaging subtypes effectively stratify NSCLC patients based on their risk levels for disease recurrence after initial curative surgery or radiotherapy, providing valuable insights for personalized treatment approaches

Tumor- and Circulating-Free DNA Methylation Identifies Clinically Relevant Small Cell Lung Cancer Subtypes

Small cell lung cancer (SCLC) is an aggressive malignancy composed of distinct transcriptional subtypes, but implementing subtyping in the clinic has remained challenging, particularly due to limited tissue availability. Given the known epigenetic regulation of critical SCLC transcriptional programs, we hypothesized that subtype-specific patterns of DNA methylation could be detected in tumor or blood from SCLC patients. Using genomic-wide reduced-representation bisulfite sequencing (RRBS) in two cohorts totaling 179 SCLC patients and using machine learning approaches, we report a highly accurate DNA methylation-based classifier (SCLC-DMC) that can distinguish SCLC subtypes. We further adjust the classifier for circulating-free DNA (cfDNA) to subtype SCLC from plasma. Using the cfDNA classifier (cfDMC), we demonstrate that SCLC phenotypes can evolve during disease progression, highlighting the need for longitudinal tracking of SCLC during clinical treatment. These data establish that tumor and cfDNA methylation can be used to identify SCLC subtypes and might guide precision SCLC therapy

Development and implementation of novel predictive biomarkers in non-small cell lung cancer – from tissue to liquid biopsy

Le cancer du poumon est la principale cause de décès liés au cancer dans le monde, tant chez les hommes que chez les femmes. Cependant, le traitement du cancer du poumon a radicalement changé au cours de ces dernières années avec la mise en place de chimiothérapies plus efficaces, mais surtout le développement de traitements ciblés qui permettent une approche thérapeutique personnalisée et avec l'introduction de l'immunothérapie qui a considérablement prolongé la survie de certains patients atteints d’un cancer du poumon non à petites cellules (CPNPC). Bien que ces nouvelles approches thérapeutiques aient permis d'obtenir des réponses parfois spectaculaires, un nombre assez important de patients sont réfractaires à ces traitements. Dans ce contexte, le développement de nouveaux biomarqueurs permettant de sélectionner le meilleur traitement pour le bon patient et au bon moment est crucial pour améliorer les résultats cliniques des patients atteints de CPNPC. Tous les biomarqueurs actuellement à l’étude ne sont pas en mesure d'améliorer cette prédiction, en particulier, la mise en place de certains biomarqueurs en routine clinique est souvent difficile, alors que les résultats préliminaires obtenus in vitro ou même dans les essais cliniques initiaux étaient prometteurs. L'objectif de la thèse a été d’évaluer et d’implémenter de nouveaux biomarqueurs prédictifs de la réponse à l’immunothérapie et aux thérapies ciblées pour la sélection thérapeutique des patients atteints de CPNPC. Dans la première partie de la thèse, est abordé l’importance des biobanques et de la maitrise des ressources biologiques comme pierre angulaire du développement de ces nouveaux biomarqueurs. Nous avons mis en place un mode de fonctionnement qui permet d'entreposer en toute sécurité des collections biologiques d'intérêt et de les utiliser pour les études de recherche de biomarqueurs. Nous décrivons comment une biobanque dédiée à une seule pathologie peut être instaurée et utilisée à des fins de recherche.Au cours de cette thèse est abordée l'évaluation génomique de l'ADN libre plasmatique (cell-free DNA : cfDNA) pour la détection des mutations spécifiques du récepteur du facteur de croissance épidermique (Epidermal growth Factor Receptor : EGFR) est étudiée et évaluée. Nous avons analysé rétrospectivement 324 patients sur une période de trois ans à partir de trois tests biologiques utilisés en routine clinique et nous avons pu démontrer que ces tests sont très « robustes » mais doivent être étroitement contrôlés afin d’éviter de faux résultats positifs ou négatifs. Nous avons ensuite évalué le séquençage à haut débit de l’ADN plasmatique chez ces patients à l'aide d'un test interne développé au laboratoire et d'un test externe et nous avons pu démontrer que ces deux tests étaient fiables pour la détection des altérations génomiques du plasma en routine clinique. Dans la dernière partie de la thèse, je décris comment l'évaluation de grands panels de séquençage ciblés capables d'évaluer la charge tumorale mutationnelle peut être utilisée pour sélectionner les patients pouvant bénéficier d’une immunothérapie anti-tumorale et quels pièges doivent être évités afin d’utiliser ce biomarqueur en routine clinique.En résumé, cette thèse montre la place croissante des nouveaux biomarqueurs permettant la stratification des patients atteints CPNPC pour adapter rapidement leur traitement et décrit les différentes étapes de l’implémentation de ces biomarqueurs tissulaires et circulants dans les soins cliniques courants.Lung cancer is the leading cause of cancer-related deaths worldwide for both men and women. However, the treatment of lung cancer has changed radically in recent years with the introduction of more effective chemotherapies, but above all the development of targeted treatments that allow a personalized therapeutic approach and the introduction of immunotherapy that has considerably prolonged the survival of some patients with non-small cell lung cancer (NSCLC). Although these new therapeutic approaches have made it possible to obtain sometimes spectacular responses, a fairly large number of patients are resistant to these treatments. In this context, the development of new biomarkers to select the best treatment for the right patient at the right time is crucial to improving clinical outcomes for NSCLC patients. Nevertheless, not all biomarkers currently under study are able to improve this prediction, in particular, the implementation of some biomarkers in clinical routine is often difficult, whereas preliminary results obtained in vitro or even in initial clinical trials were promising.The objective of the thesis was to evaluate and implement new biomarkers that predict the response to immunotherapy and targeted therapies for the therapeutic selection of NSCLC patients. The first part of the thesis discusses the importance of biobanks and the control of biological resources as a cornerstone for the development of these new biomarkers. We have implemented an operating procedure that allows us to safely store biological collections of interest and use them for biomarker research studies. We describe how a biobank dedicated to a single pathology can be established and used for research purposes.Additionally, the genomic evaluation of cell-free DNA (cfDNA) for the detection of specific mutations of the Epidermal growth Factor Receptor receptor (EGFR) is studied and evaluated. We retrospectively analyzed 324 patients over a three-year period from three biological tests used in routine clinical practice and were able to demonstrate that these tests are very robust but must be closely controlled to avoid false positive or negative results. We then evaluated the next-generation sequencing (NGS) of plasma DNA using an internal test developed in the laboratory and an external test and were able to demonstrate that both tests were reliable for the detection of genomic alterations in plasma in clinical routine. In the last part of the thesis, I describe how the evaluation of large targeted sequencing panels capable of assessing mutation tumor load can be used to select patients for anti-tumor immunotherapy and what pitfalls should be avoided in order to use this biomarker in clinical routine.In summary, this thesis demonstrates the importance of novel biomarkers for the stratification ofpatients undergoing therapy in NSCLC and contributed to the implementation of tissue and liquidbiopsy-based biomarkers in routine clinical care

Never Travel Alone: The Crosstalk of Circulating Tumor Cells and the Blood Microenvironment

International audienceCommonly, circulating tumor cells (CTCs) are described as source of metastasis in cancer patients. However, in this process cancer cells of the primary tumor site need to survive the physical and biological challenges in the blood stream before leaving the circulation to become the seed of a new metastatic site in distant parenchyma. Most of the CTCs released in the blood stream will not resist those challenges and will consequently fail to induce metastasis. A few of them, however, interact closely with other blood cells, such as neutrophils, platelets, and/or macrophages to survive in the blood stream. Recent studies demonstrated that the interaction and modulation of the blood microenvironment by CTCs is pivotal for the development of new metastasis, making it an interesting target for potential novel treatment strategies. This review will discuss the recent research on the processes in the blood microenvironment with CTCs and will outline currently investigated treatment strategies

Circulating Tumor Cell Detection in Lung Cancer: But to What End?

The understanding of the natural history and biology of lung cancer has been enhanced by studies into circulating tumor cells (CTCs). Fundamental and translational research, as well as clinical trials in the characterization and behavior of these cells, have constantly contributed to improving understanding within the domain of thoracic oncology. However, the use of these CTCs as prognostic and predictive biomarkers has not been adopted to the same extent as circulating free DNA (cf-DNA) in plasma, in the daily practice of thoracic oncologists. However, recent technological advances have firmly put the detection and characterization of CTCs in thoracic oncology back on the agenda, and have opened up perspectives for their routine clinical use. This review discusses the major advances of using CTCs in the domain of thoracic oncology, as well as the envisaged short- and long-term prospects