Interstitial lung diseases, particularly idiopathic pulmonary fibrosis (IPF), have dismal prognoses, with a median survival of 3-5 years, owing to a lack of early biomarkers or effective treatments. This review highlights the lung microbiome as a key biological factor in IPF pathogenesis and a promising therapeutic target. Elevated burdens of pathogenic bacteria, including Streptococcus and Staphylococcus, in bronchoalveolar lavage fluid correlate with accelerated progression and higher mortality. These bacteria release toxins and activate Th17-driven inflammation, providing mechanistic links to alveolar injury and fibrosis. Host genetics and systemic factors, including oral-gut-lung interactions, further shape disease progression. Although antibiotic trials have been unsuccessful, embracing the microbiome as an active participant in IPF may open unprecedented opportunities for personalized interventions.
Shared epitopes pose safety and efficacy issues for T-cell immunotherapy. To characterize the extent of this problem, we performed a computational analysis establishing a complete atlas of shared identical sequences across the human and murine proteomes. Unlike bacterial or viral antigens, self-antigens, including tumor-associated antigens (TAAs), frequently contain sequences of sufficient length to generate identical epitopes in other self-proteins. Epitopes from these shared sequences can theoretically reduce target specificity, confound immunomonitoring studies, and contribute to pre-existing immune tolerance toward TAAs. Notably, a subset of TAAs identified in this atlas is free of this drawback, providing a new criterion for antigen prioritization in cancer immunotherapy. To facilitate the detection of shared sequences, a web server has been made available at https://epitopemapper.ircan.org/ and the open-source code at https://github.com/IRCAN/EpitopeMapper.
Processing bodies (P-bodies) are cytoplasmic, membraneless organelles that play a key role in regulating RNA translation. To identify new pathways controlling their formation, we conducted a Food and Drug Administration (FDA)-approved drug screen. We found that glucocorticoids, among the most prescribed medicines, significantly increase P-body numbers across diverse epithelial cell types. This effect was fully reversible after glucocorticoid withdrawal, illustrating the adaptive dynamics of P-bodies. Using genetic invalidation and rescue approaches, we demonstrated that this accumulation requires the Glucocorticoid Receptor alpha isoform. P-body accumulation was associated with the sequestration of P-body-specific-targeted mRNAs, altering their translation yield. Notably, this translational regulation depends on transcript sequence features rather than abundance, with AU-rich mRNA transcripts being sequestered and GC-rich mRNAs preferentially translated under glucocorticoid treatment. Furthermore, we linked the decrease of LSM14B, a negative regulator of P-bodies, under glucocorticoid treatment to P-body reshaping. Our results reveal that, beyond their known transcriptional activity, prolonged exposure to glucocorticoids influences mRNA post-transcription and translation through a nucleotide composition-based mechanism. ### Competing Interest Statement The authors have declared no competing interest. Agence Nationale de la Recherche, ANR-11-LABX-0028-01, ANR-15-IDEX-01, ANR-23-IAHU-0007, ANR-10-IDEX-0002, ANR-20-SFRI-0012 Fondation ARC pour la Recherche sur le Cancer, https://ror.org/0489qz649, Canc’air GENExposomics, PJA-20191209562 Cancéropôle PACA, https://ror.org/01mwvah42 Institut National du Cancer, INCa_18414 Institut Thématique Cancer, 18CN045 Ministère de l’Enseignement Supérieur et de la Recherche, https://ror.org/03sjk9a61
Tumor-associated antigens (TAAs) are the targets of several therapeutic cancer vaccines. However, many TAAs contain epitopes identical to unintended targets, creating shared epitopes with other human proteins in normal tissues. Moreover, for some TAAs like ASCL2, KLK2, TPTE, CLDN6, and PSMA, the off-targeted proteins are often expressed at a higher level in healthy tissues than the target in cancer, potentially impacting both the safety and the efficacy of T cell immunity. Altogether, our analysis indicates a suboptimal design of several cancer vaccines currently in clinical development: ATP128, BNT111, BNT112, BNT116, INO-5401. We recommend that next-generation cancer vaccines should integrate rigorous epitope filtering strategies to eliminate shared sequences in TAAs.
Shared epitopes create safety and efficacy issues for T-cell immunotherapy. In order to facilitate the monitoring of immune responses and the engineering required to solve this problem, we performed a computational proteome-wide epitope screening to establish the complete atlas of shared epitopes in the human and murine proteomes. Unlike bacterial or viral antigens, self-antigens like tumor-associated antigens (TAAs) frequently contained a high level of shared MHC-II epitopes identical to unintended other self-proteins. Therefore, shared epitopes should be a mandatory and systematic concern in studies using TAA. Noticeably, a subset of TAAs identified in this atlas is free of this drawback. Therefore, this dataset will be essential for immunologists designing cancer vaccines, but also to interpret immunomonitoring studies against self-antigens in oncology and autoimmunity. To facilitate the detection of common epitopes, a web server has been made available at . ### Competing Interest Statement GK is shareholder of Telomium, a company developing cancer vaccines.
Immune checkpoint therapies (ICT) have transformed the treatment of cancer over the past decade. However, many patients do not respond or suffer relapses. Successful immunotherapy requires epitope spreading, but the slow or inefficient induction of functional antitumoral immunity delays the benefit to patients or causes resistances. Therefore, understanding the key mechanisms that support epitope spreading is essential to improve immunotherapy. In this review, we highlight the major role played by B-cells in breaking immune tolerance by epitope spreading. Activated B-cells are key Antigen-Presenting Cells (APC) that diversify the T-cell response against self-antigens, such as ribonucleoproteins, in autoimmunity but also during successful cancer immunotherapy. This has important implications for the design of future cancer vaccines.
The past several years have provided a more profound understanding of the role of microbial species in the lung. The respiratory tract is a delicate ecosystem of bacteria, fungi, parasites, and viruses. Detecting microbial DNA, pathogen-associated molecular patterns (PAMPs), and metabolites in sputum is poised to revolutionize the early diagnosis of lung cancer. The longitudinal monitoring of the lung microbiome holds the potential to predict treatment response and side effects, enabling more personalized and effective treatment options. However, most studies into the lung microbiota have been observational and have not adequately considered the impact of dietary intake and air pollutants. This gap makes it challenging to establish a direct causal relationship between environmental exposure, changes in the composition of the microbiota, lung carcinogenesis, and tumor progression. A holistic understanding of the lung microbiota that considers both diet and air pollutants may pave the way to improved prevention and management strategies for lung cancer.
BackgroundMultiple Myeloma (MM) is the second most common hematological malignancy, characterized by the accumulation of monoclonal plasmocytes in the bone marrow. Despite advancements with proteasome inhibitors, immunomodulatory agents, and CD38-targeting antibodies, MM remains largely incurable due to resistant clones and frequent relapses. The success of the proteasome inhibitor bortezomib (BTZ) in MM treatment highlights the critical role of the ubiquitin-proteasome system (UPS) in this disease. Deubiquitinases (DUBs), which regulate protein stability, interactions, and localization by removing ubiquitin modifications, have emerged as promising therapeutic targets in various cancers, including MM.MethodsThrough a comprehensive loss-of-function screen, we identified USP39 as a critical survival factor for MM cells. Gene Set Enrichment Analysis (GSEA) was employed to correlate USP39 mRNA levels with clinical outcomes in MM patients. USP39 protein expression was evaluated via immunohistochemistry (IHC) on bone marrow samples from MM patients and healthy controls. The impact of USP39 knockdown via SiRNA was assessed through in vitro assays measuring cellular metabolism, clonogenic capacity, cell cycle progression, apoptosis, and sensitivity to BTZ. Co-immunoprecipitation and deubiquitination assays were conducted to elucidate the interaction and regulation of ZEB1 by USP39. Finally, in vitro and in vivo zebrafish experiments were used to characterize the biological consequences of ZEB1 regulation by USP39.ResultsOur study found that elevated USP39 mRNA levels are directly associated with shorter survival in MM patients. USP39 protein expression is significantly higher in MM patient plasmocytes compared to healthy individuals. USP39 knockdown inhibits clonogenic capacity, induces cell cycle arrest, triggers apoptosis, and overcomes BTZ resistance. Gain-of-function assays revealed that USP39 stabilizes the transcription factor ZEB1, enhancing the proliferation and the trans-migratory potential of MM cells.ConclusionsOur findings highlight the critical role of the deubiquitinase USP39, suggesting that the USP39/ZEB1 axis could serve as a potential diagnostic marker and therapeutic target in MM.
Rationale Multiple Myeloma (MM) stands as the second most common hematological malignancy characterized by the accumulation of monoclonal plasmocytes within the bone marrow. Despite the introduction of proteasome inhibitors, immunomodulatory agents and CD38-targeting antibodies which have extended survival rates, the disease remains incurable for most patients due to the emergence of resistant clones and frequent relapses. The efficacy of the proteasome inhibitor bortezomib (BTZ) in MM treatment underscores the critical role of the ubiquitin proteasome system (UPS) in this cancer. Deubiquitinases (DUBs), a class of enzymes governing the stability, interactions or localization of cellular proteins by removing ubiquitin modifications, have emerged as promising therapeutic targets across various cancers, including MM. Methods Through an exhaustive loss-of-function approach, we have identified for the first time USP39 DUB as a pivotal survival determinant for MM cells. Results Our analysis reveals a direct correlation between heightened USP39 mRNA levels and shorter survival in MM patients. Additionally, robust USP39 protein expression is observed in MM patient plasmocytes compared to healthy counterparts. Knockdown of Usp39 not only impedes clonogenic capabilities, but also induces apoptosis, triggers cell cycle arrest and overcomes BTZ resistance. Complementary gain-of-function assays, further elucidate how USP39, by stabilizing the transcription factor ZEB1, enhances the trans-migratory potential of MM cells. Conclusions In summary, our findings underscores the pivotal role of the deubiquitinase USP39, suggesting that targeting the USP39/ZEB1 axis hold promise as a prospective diagnostic marker and therapeutic target in MM. ### Competing Interest Statement The authors have declared no competing interest. * ### ABBREVATION ASCT : stem cell auto transplantation BM : bone marrow BTZ : bortezomib DUB : deubiquitinase EMT : epithelial-to-mesenchymal transition GFP : green fluorescent protein GSEA : Gene Set enrichment analysis HCC : hepatocellular carcinoma IMiDs : immunomodulatory drugs JAAMs : JAB1/PAB1/MPN-domain containing metallo-enzyme MGUS : monoclonal gammopathy of undetermined significance MJDs : Machado-Joseph disease protein domain proteases MM : multiple myeloma Monoclonal antibodies : mAbs NR : non relevant OTUs : ovarian tumor-related proteases PIs : proteasome inhibitors siRNA : small interfering RNA Ub : ubiquitin Ubis : Ubiquitinases UCHs : ubiquitin carboxy-terminal hydrolases UPS : ubiquitin proteasome system USP39 : ubiquitin-specific peptidase 39 USPs : ubiquitin-specific proteases WT : wild type ZEB1 : Zinc-finger E-box-binding homeobox 1
AVI file - 5901K, Video 5 (related to Fig. 2G) is a time-lapse recording of a mononucleate a3-/- cell that formed a tetranucleate cell after two rounds of abortive mitosis.
<p>AVI file - 875K, Video 2 (related to Fig. 2D) shows the delayed abscission of an a3-/- cell that remained connected by an intracellular bridge for up to 8 h 45 min before separating.</p>
Nearly fifty million older people suffer from neurodegenerative diseases, including Alzheimer (AD) and Parkinson (PD) disease, a global burden expected to triple by 2050. Such an imminent "neurological pandemic" urges the identification of environmental risk factors that are hopefully avoided to fight the disease. In 2022, strong evidence in mouse models incriminated defective lysosomal acidification and impairment of the autophagy pathway as modifiable risk factors for dementia. To date, the most prescribed lysosomotropic drugs are proton pump inhibitors (PPIs), chloroquine (CQ), and the related hydroxychloroquine (HCQ), which belong to the group of disease-modifying antirheumatic drugs (DMARDs). This commentary aims to open the discussion on the possible mechanisms connecting the long-term prescribing of these drugs to the elderly and the incidence of neurodegenerative diseases.Abbreviations: AD: Alzheimer disease; APP-βCTF: amyloid beta precursor protein-C-terminal fragment; BACE1: beta-secretase 1; BBB: brain blood barrier; CHX: Ca2+/H+ exchanger; CMI: cognitive mild impairment; CQ: chloroquine; DMARD: disease-modifying antirheumatic drugs; GBA1: glucosylceramidase beta 1; HCQ: hydroxychloroquine; HPLC: high-performance liquid chromatography; LAMP: lysosomal associated membrane protein; MAPK/JNK: mitogen-activated protein kinase; MAPT: microtubule associated protein tau; MCOLN1/TRPML1: mucolipin TRP cation channel 1; NFE2L2/NRF2: NFE2 like bZIP transcription factor 2; NRBF2: nuclear receptor binding factor 2; PANTHOS: poisonous flower; PD: Parkinson disease; PIK3C3: phosphatIdylinositol 3-kinase catalytic subunit type 3; PPI: proton pump inhibitor; PSEN1: presenilin 1, RUBCN: rubicon autophagy regulator; RUBCNL: rubicon like autophagy enhancer; SQSTM1: sequestosome 1; TMEM175: transmembrane protein 175; TPCN2: two pore segment channel 2; VATPase: vacuolar-type H+-translocating ATPase; VPS13C: vacuolar protein sorting ortholog 13 homolog C; VPS35: VPS35 retromer complex component; WDFY3: WD repeat and FYVE domain containing 3; ZFYVE1: zinc finger FYVE-type containing 1.
AVI file - 2112K, Video 4 (related to Fig. 2F) illustrates the failed abscission of a mononucleated a3-/- cell that exited mitosis as a binucleated cell after 18 attempts at cleavage furrow formation. Note that this cell developed ectopic furrows, which led to the formation of anuclear fragments that fused back to the cell.
AVI file - 2696K, Video 3 (related to Fig. 2E) is a time-lapse recording of four pairs of a3-/- cells that entered mitosis synchronously, likely bridged sister cells. Pairs of cells that entered mitosis synchronously are outlined in color in the first frame, and then marked with dots in the next frame to help visualize their progression in mitosis.
The past decade has witnessed a revolution in cancer treatment by shifting from conventional therapies to immune checkpoint inhibitors (ICIs). These immunotherapies unleash the host immune system against the tumor and have achieved unprecedented durable remission. However, 80% of patients do not respond. This review discusses how bacteria are unexpected drivers that reprogram tumor immunity. Manipulating the microbiota impacts on tumor development and reprograms the tumor microenvironment (TME) of mice on immunotherapy. We anticipate that harnessing commensals and the tumor microbiome holds promise to identify patients who will benefit from immunotherapy and guide the choice of new ICI combinations to advance treatment efficacy.
Metastatic uveal melanomas are highly resistant to all existing treatments. To address this critical issue, we performed a kinome-wide CRISPR-Cas9 knockout screen, which revealed the LKB1-SIK2 module in restraining uveal melanoma tumorigenesis. Functionally, LKB1 loss enhances proliferation and survival through SIK2 inhibition and upregulation of the sodium/calcium (Na+ /Ca2+ ) exchanger SLC8A1. This signaling cascade promotes increased levels of intracellular calcium and mitochondrial reactive oxygen species, two hallmarks of cancer. We further demonstrate that combination of an SLC8A1 inhibitor and a mitochondria-targeted antioxidant promotes enhanced cell death efficacy in LKB1- and SIK2-negative uveal melanoma cells compared to control cells. Our study also identified an LKB1-loss gene signature for the survival prognostic of patients with uveal melanoma that may be also predictive of response to the therapy combination. Our data thus identify not only metabolic vulnerabilities but also new prognostic markers, thereby providing a therapeutic strategy for particular subtypes of metastatic uveal melanoma.
Cholesterol efflux pathways could be exploited in tumor biology to unravel cancer vulnerabilities. A mouse model of lung-tumor-bearing KRASG12D mutation with specific disruption of cholesterol efflux pathways in epithelial progenitor cells promoted tumor growth. Defective cholesterol efflux in epithelial progenitor cells governed their transcriptional landscape to support their expansion and create a pro-tolerogenic tumor microenvironment (TME). Overexpression of the apolipoprotein A-I, to raise HDL levels, protected these mice from tumor development and dire pathologic consequences. Mechanistically, HDL blunted a positive feedback loop between growth factor signaling pathways and cholesterol efflux pathways that cancer cells hijack to expand. Cholesterol removal therapy with cyclodextrin reduced tumor burden in progressing tumor by suppressing the proliferation and expansion of epithelial progenitor cells of tumor origin. Local and sys-temic perturbations of cholesterol efflux pathways were confirmed in human lung adenocarcinoma (LUAD). Our results position cholesterol removal therapy as a putative metabolic target in lung cancer progeni-tor cells.