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Limitations of encapsidation of recombinant self-complementary adeno-associated viral genomes in different serotype capsids and their quantitation.

We previously reported that self-complementary adeno-associated virus (scAAV) type 2 genomes of up to 3.3 kb can be successfully encapsidated into AAV2 serotype capsids. Here we report that such oversized AAV2 genomes fail to undergo packaging in other AAV serotype capsids, such as AAV1, AAV3, AAV6, and AAV8, as determined by Southern blot analyses of the vector genomes, although hybridization signals on quantitative DNA slot-blots could still be obtained. Recently, it has been reported that quantitative real-time PCR assays may result in substantial differences in determining titers of scAAV vectors depending on the distance between the primer sets and the terminal hairpin structure in the scAAV genomes. We also observed that the vector titers determined by the standard DNA slot-blot assays were highly dependent on the specific probe being used, with probes hybridizing to the ends of viral genomes being significantly overrepresented compared with the probes hybridizing close to the middle of the viral genomes. These differences among various probes were not observed using Southern blot assays. This overestimation of titer is a systemic error during scAAV genome quantification, regardless of viral genome sequences and capsid serotypes. Furthermore, different serotypes capsid and modification of capsid sequence may affect the ability of packaging intact, full-length AAV genomes. Although the discrepancy is modest with wild-type serotype capsid and short viral genomes, the measured titer could be as much as fivefold different with capsid mutant vectors and large genomes. Thus, based on our data, we suggest that Southern blot analyses should be performed routinely to more accurately determine the titers of recombinant AAV vectors. At the very least, the use of probes/primers hybridizing close to the mutant inverted terminal repeat in scAAV genomes is recommended to avoid possible overestimation of vector titers.

Blotting, Southern

Metagenome-resolved evidence that soluble factors in granular activated carbon-amended reactor effluent reprogram propionate metabolism and methanogenic pathways.

Granular activated carbon (GAC) enhances anaerobic digestion performance, yet the mechanisms underlying reactor-scale improvements remain incompletely understood, particularly how GAC affects biomass not attached to its surface. Here, sludge from a non-GAC up-flow anaerobic sludge blanket reactor was incubated with 0.45-&#x3bc;m-filtered effluents from non-GAC and GAC-amended reactors under repeated propionate loading, followed by genome-resolved metagenomics. GAC-reactor effluent increased methane yield from 64&#x202f;&#xb1;&#x202f;3% to 76&#x202f;&#xb1;&#x202f;3% (p&#x202f;<&#x202f;0.01) in the absence of GAC particles. A non-redundant catalog of 170 quality-filtered metagenome-assembled genomes (MAGs) was recovered, enabling pathway- and gene-set quantification. Genomic potential for both major propionate-oxidation routes increased in the GAC-effluent group relative to the non-GAC group, with a larger increase for the methylmalonyl-CoA (MMC) route than for the dismutation route (1.289- versus 1.221-fold). Accordingly, the MMC-to-dismutation preference ratio was 5.60% higher in the GAC-effluent group, alongside a broader carrier base. Cobamide potential shifted toward remodeling and cobamide-dependent use rather than increased de novo corrin-ring synthesis. Candidate electron-transfer architectures were also rebalanced: PilA-associated carriers became less prominent, whereas maturation-supported multiheme cytochrome carriers increased from 22.96% to 34.90% of community abundance, although H2/formate-module carriers remained prevalent. Quorum-sensing systems underwent pathway- and carrier-specific redistribution, while all eight curated extracellular-polysaccharide modules showed higher mean gene abundance in the GAC-effluent composite. These findings show that a filter-passing effluent fraction can extend GAC-associated effects beyond direct particle contact and link enhanced methanogenesis to a broader, redistributed network of metabolic, redox, and coordination capacities. This expands the mechanistic framework of conductive-material-assisted anaerobic digestion and provides a basis for harnessing GAC-derived functions throughout the reactor.

Extracellular polymeric substances (EPS)

A digital PCR-based platform for rapid assessment of chloroplast stress adaptation in microalgal metabolic engineering.

Microalgae rapidly adjust their chloroplast physiology in response to environmental stress, and these adaptive responses are closely associated with cellular fitness and metabolic performance. However, conventional assessments of stress adaptation primarily rely on growth characteristics, pigment accumulation, or physiological measurements, which often require extended cultivation periods and may not capture early molecular responses. In this study, we introduce a digital PCR (dPCR)-based platform for rapid assessment of chloroplast stress adaptation in microalgae. The platform quantifies the chloroplast-to-nuclear genome copy number ratio (C/N ratio) using multiplex dPCR and utilizes this metric as a molecular indicator of chloroplast acclimation. As a proof-of-concept, the assay was applied to the halotolerant microalga Dunaliella salina cultivated under different salinity stress conditions. Distinct temporal changes in the C/N ratio were observed across salinity treatments, indicating dynamic chloroplast genome remodeling during stress adaptation. The assay enabled sensitive detection of chloroplast responses at early cultivation stages, prior to the appearance of clear phenotypic differences. These findings demonstrate that chloroplast-to-nuclear genome quantification by dPCR provides a rapid and reproducible approach for monitoring chloroplast stress adaptation in microalgae. The proposed platform offers a practical molecular tool for strain evaluation, cultivation optimization, and stress-response studies, and may support future applications in microalgal biotechnology and industrial production systems.

Microalgae

Long-Term Correction of Murine Glycogen Storage Disease Type III by AAV-Mediated Gene Therapy Using an Immunotolerizing Dual Promoter to Express Bacterial Pullulanase.

BACKGROUND: We recently reported an innovative gene therapy approach for GSD III using a recombinant adeno-associated virus serotype 9 vector (AAV9-Dual-Pull) expressing a bacterial debranching enzyme (pullulanase) driven by a tandem dual promoter that consists of an immunotolerizing liver-specific promoter (LSP) and the ubiquitous CMV enhance/chicken &#x3b2;-actin (CB) promoter. In this follow-up study, we evaluated the long-term efficacy of this gene therapy in GSD IIIa mice. METHODS: Three-month-old GSD IIIa mice were intravenously injected with AAV9-LSP-Pull or AAV9-Dual-Pull at the same dose (2.5 &#xd7; 1013 vg/kg). Tissues were collected after 9 months for AAV genome quantification, pullulanase expression determination, and glycogen content measurement. Liver and muscle enzymes in plasma and disease biomarker in urine were analyzed at multiple time points to examine the correction of liver and muscle damage. Behavioral tests were performed during the course of AAV treatment to evaluate the improvement of muscle function. RESULTS: The AAV-Dual-Pull treatment led to persistent pullulanase expression and effective glycogen reduction in the liver, heart, and skeletal muscle, accompanied by the reversal of liver fibrosis, decrease of plasma enzyme activities, and long-term improvement of muscle function. The AAV-LSP-Pull treatment showed a better therapeutic efficacy in the liver but had no effect on the cardiac and skeletal muscles. CONCLUSION: Our results demonstrated the long-term efficacy and safety of systemic AAV9-Dual-Pull delivery in GSD IIIa mice. Future studies will test this gene therapy approach in GSD IIIa dogs prior to the clinical translation to GSD III patients.

AAV gene therapy

A Quantitative Real-Time PCR Assay for Measuring Poxvirus Replication and Cell Binding.

Quantitative real-time PCR (qPCR) is a fast and reliable method to quantify viral genomes as a surrogate to titering on monolayers of cells for measuring virus replication. Whether it be for determining the number of virions released, the total number of genomes produced during infection, or the number of virions bound to a cell, qPCR assays can be adapted to quickly enumerate total viral genomes in a broad range of experiments comparing virus replication under different conditions. In addition, qPCR offers several advantages compared to plaque assays including time, linearity over 9 logs, and scalability from tens-to-hundreds of samples, depending on the qPCR machine. Here we describe a qPCR assay for quantifying vaccinia virus' dsDNA genome that can be used to determine the total number of virions produced. Furthermore, we describe a straightforward protocol for a cell-binding assay that is sensitive enough to use with small concentrations of inoculating virions. This protocol is suitable for measuring the cell-binding ability of mutations that affect virus production and infectivity.

Virus Replication

Tumor-Intrinsic Blood and Imaging Correlatives in Advanced Prostate Cancer Treated with Combination Radiopharmaceutical Therapy and Immunotherapy.

The PRINCE trial showed the clinical activity for 177Lu-PSMA-617 in combination with pembrolizumab for metastatic castration-resistant prostate cancer. To refine patient selection and improve response monitoring strategies to this combination, we investigated candidate tumor-intrinsic biomarkers of treatment response and resistance. Methods: We performed circulating tumor DNA (ctDNA), circulating tumor cell (CTC), and PET imaging analyses at baseline, 12 wk on-treatment, and disease progression in participants enrolled in PRINCE (n = 37). We performed targeted sequencing for ctDNA quantification and genomic analysis of more than 70 prostate cancer genes. CTC enumeration was performed on the EpicSciences platform and was combined with selective single-cell whole-genome sequencing. PET imaging included serial PSMA PET as well as 18F-FDG PET imaging at baseline. Results: A low baseline ctDNA fraction and high PSMA avidity in metastatic lesions were linked to superior treatment responses and may have composite biomarker value. Genomic alterations in tumor suppressor genes TP53, RB1, or PTEN were associated with higher 18F-FDG avidity and metabolic tumor volume on 18F-FDG PET imaging and worse prognosis. At 12-wk on-treatment, both ctDNA detection and PSMA PET imaging were strong indicators of response depth and durability. At disease progression, PSMA expression on PET imaging was lower compared with baseline and supported by subclonal remodeling of ctDNA and CTC copy number profiles and by clonal expansions of tumor suppressor gene mutations. Conclusion: We provide the first integrated molecular and imaging insights into determinants of response and resistance to combined radiopharmaceutical therapy and immunotherapy in prostate cancer and propose biomarker strategies to inform future clinical development.

177Lu-PSMA-617

Clinical and Epidemiological Insights into a Parainfluenza Virus Type 3 Outbreak in Multiple Myeloma Patients.

Human parainfluenza virus type 3 (HPIV-3) can be responsible for mild to severe respiratory infections and hospital epidemics. We investigated an outbreak in a hematology unit. Respiratory viruses were screened using multiplex PCR. HPIV-3 quantification and whole-genome sequencing were performed on HPIV-3 positive respiratory samples. Clinical characteristics, infection progression, incidence rates of respiratory viruses within the hospital and detection of respiratory viruses were documented, along with the reinforcement of infection prevention and control (IPC) measures implemented. Between November 2022, and January 2023, HPIV-3 was identified in 20 of 113 hematology patients (17.7%), of whom 80% had multiple myeloma. A majority of HPIV-3-positive patients developed pneumonia (60%), and mortality was notably higher (35%) compared to patients who were negative (3%, p&#x2009;<&#x2009;0.0001). Respiratory HPIV-3 viral loads were similar between patients with and without pneumonia. In parallel, HPIV-3 incidence in the hospital overall was lower than in the hematology unit (p&#x2009;<&#x2009;0.0001). Air virus screening showed the detection of HPIV-3 in the air in different areas, and whole-genome sequencing confirmed the circulation of a single HPIV-3 strain. Strengthened IPC measures were associated with the containment of the outbreak. HPIV-3 has high epidemic potential in patients with multiple myeloma and causes severe infections. Our findings highlight the need for routine HPIV-3 testing in hematology units.

Humans

Genome-wide survey of spliceosomal snRNA transcripts across hundreds of human biosamples reveals abundant transcription but low maturation level of snRNA variants.

Small nuclear RNAs (snRNAs) are essential components of the spliceosome and are encoded by large, multicopy gene families. However, their genome-wide identification and quantification have remained challenging due to high sequence similarity among family members. To address this, we utilized RAMPAGE (Rapid Amplification of cDNA Ends) data from the ENCODE project to comprehensively profile nascent transcription of spliceosomal snRNAs across 115 human biosamples. We identified 74 expressed snRNA variants, characterized by canonical promoter features including bidirectional transcription flanking a positioned nucleosome, active histone modifications, and evolutionary conservation- features largely absent from unexpressed variants. These transcriptional events were corroborated by total RNA-seq and Bru-seq data, yet the majority of these variants showed extremely low levels in small RNA-seq, indicating post-transcriptional bottlenecks for snRNA processing and maturation. Our findings reveal new layers of regulation in snRNA variant expression and suggest that selective post-transcriptional processing plays a critical role in shaping the functional snRNA repertoire and its contribution to splicing regulation.

Journal Article

Adaptation of the Cyst Nematode Globodera pallida to the Colinear Potato Resistant QTLs GpaVvrn and GpaVspl Involved Distinct Genomic Regions and Absence of Cross-Virulence.

The use of alternative methods to control cyst nematode populations has accelerated since the ban of chemical nematicides in Europe. The resistant QTL GpaVvrn, derived from the wild species Solanum vernei, is widely present in resistant European potato cultivars and provides strong protection against Globodera pallida populations although a risk of resistance breakdown has already been demonstrated in both experimental evolution studies and field populations. The wild relative S. sparsipilum, harbouring the resistant QTL GpaVspl, would be an interesting alternative source of resistance to control virulent G. pallida. The goal of the present study was to understand the genomics of adaptation of the nematode to these two colinear resistant QTLs. Starting with two natural populations, an experimental evolution approach allowed, after 10 generations on resistant potato genotypes, selecting independent nematode lineages adapted to each QTL. These virulent lineages were analysed through a combination of phenotyping and genome scans approaches. Phenotyping enabled the quantification of virulence levels and confirmed resistance breakdowns. Pool-Seq whole genome sequencing followed by genome scan analyses identified genomic regions under selection, potentially involved in the adaptive mechanisms to each resistance factor. Candidate genes within these regions provided insights into the genetic basis of adaptation, revealing effectors known to suppress plant immunity. As genome scans highlighted distinct genomic regions for the adaptation to both resistant factors, we were able to predict and phenotypically confirm the absence of cross-virulence between nematode lineages evolving on GpaVvrn and GpaVspl. These findings have significant implications for the design of effective and sustainable resistance management strategies.

Animals

Sex-specific ethylene responses drive floral sexual plasticity in Cannabis sativa.

Cannabis sativa L. exhibits pronounced sexual plasticity in which both XX and XY plants can undergo floral phenotypic sex reversal in response to ethylene modulation, yet the underlying molecular mechanisms remain poorly defined. Here, we present the most extensive multi-omic analysis of ethylene-induced sex change in C. sativa to date, integrating over 130 RNA-seq libraries, ethylene pathway metabolite quantification, and whole-genome sequencing across three XX and XY genotypes. Treatments with silver thiosulfate and ethephon induced more than 80% phenotypic conversion, but transcriptomic responses diverged sharply between XX and XY plants. Profiling 47 ERGs revealed 14 high-confidence candidates, including CsACS1, CsACO5, CsERF1, and CsMTN, with sex-specific and temporal expression patterns that show dynamic ethylene mediation of plasticity. Early transcriptional activation occurred prior to the emergence of flowers, within 18&#x2009;h of sex-change treatments and the photoperiod-induced transition to flowering. As opposite-sex floral tissues emerged, ethylene-related gene expression shifted accordingly within developing floral organs, with distinct sets of genes stabilizing the opposite-sex phenotype in XX and XY plants. Several candidates were located in non-recombining regions of the X chromosome or were absent from the Y chromosome, and most exhibited low nucleotide diversity, consistent with functional constraint. These results provide a high-resolution view of ethylene-responsive sexual plasticity in cannabis and show that the shared capacity for sex reversal in XX and XY plants is implemented through distinct regulatory trajectories that produce opposite-sex floral phenotypes. This work expands the mechanistic understanding of sex expression in dioecious species and identifies candidate genes relevant to the development of sex-stable cultivars.

Ethylenes

Acrocomia aculeata (Mbokaja) Kernel Oil Inhibits Herpes Simplex Virus 1 Replication and Promotes Cutaneous Wound Healing in Infected Mice.

Background/Objectives: Herpes simplex virus type 1 (HSV-1) is a global and prevalent pathogen, presenting significant clinical challenges because of its recurring infections, the development of drug resistance and severe clinical complications. This study evaluated the antiviral efficacy against HSV-1 of Acrocomia aculeata (A. aculeata) kernel oil, a Neotropical palm native to the Americas. Methods: The chemical profile of A. aculeata kernel oil was determined by gas chromatography with flame ionization detection (GC-FID). Antiviral activity was assessed using dose-response curves, time-of-addition assays, and quantification of intracellular viral genomes, viral gene transcripts, and IL-6 expression. A. aculeata kernel oil's antiviral effect was also evaluated using an in vivo HSV-1 cutaneous infection model. Results: GC-FID analysis revealed lauric, oleic, and myristic acids as predominant components in the kernel oil. A. aculeata kernel oil exhibited potent antiviral activity against HSV-1. The oil inhibited HSV-1 early step post-entry, reducing the mRNA levels of the immediate-early genes ICP4 and ICP22, leading to the downregulation of early and late viral gene expression and intracellular viral genome. Furthermore, the oil suppressed IL-6 expression in infected cells. Importantly, A. aculeata kernel oil promoted the healing of cutaneous lesions in HSV-1-infected mice. Conclusions: These findings demonstrate that A. aculeata kernel oil is a promising candidate for developing novel antiviral and topical therapies against HSV-1.

Animals

Gut microbiota-driven indole-3-propionic acid and kynurenine production is associated with improved metabolic adaptation in periparturient dairy cows.

BACKGROUND: Gastrointestinal microbes convert tryptophan into various bioactive metabolites that influence host energy metabolism; however, these mechanisms are not well understood in periparturient dairy cows, which experience marked metabolic challenges during this period. RESULTS: In this study, we used periparturient dairy cows with rumen and ileal cannulas as in vivo models. Blood, rumen fluid, ileal digesta, and fecal samples were collected at four time points during the periparturient period. By combining metagenome-assembled genomes (MAGs) and targeted metabolite quantification, we&#xa0;characterized microbial tryptophan metabolism and associated metabolite profiles during the periparturient period. The results showed that postpartum cows exhibited significantly increased serum concentrations of triglyceride (TG), aspartate aminotransferase (AST), &#x3b2;-hydroxybutyrate (BHBA), and total bilirubin (T-Bil) compared with prepartum cows, together with decreased levels of several tryptophan metabolites, including indole-3-propionic acid (IPA) and kynurenine (KYN), indicating that tryptophan deficiency might aggravate metabolic disturbances. Metagenomic analysis identified 578 high-quality MAGs, of which 461 contained genes involved in microbial tryptophan metabolic pathways. Among these, the ruminal taxon CAG-791 harbors acdA and contributes to IPA production, whereas the hindgut taxon Treponema_D harbors kynB and promotes KYN formation. Decreases in both taxa were consistent with the reduced levels of these metabolites observed above. In a follow-up in vivo trial with tryptophan supplementation, the abundance of CAG-791 and Treponema_D&#xa0;increased, along with tryptophan-derived metabolites (IPA and KYN), which further partially mitigated metabolic disturbances. CONCLUSIONS: These findings characterize spatial and temporal changes in tryptophan metabolites and gut microbial features in periparturient dairy cows, and provide integrated evidence that alterations in tryptophan metabolism are associated with postpartum metabolic adaptation, thereby supporting the potential of tryptophan-targeted nutritional strategies to improve metabolic health in dairy cows.

Gastrointestinal microbiome

Emergence of cefiderocol resistance in carbapenem-resistant Escherichia coli ST167 prior to clinical use: A multifactored resistance landscape.

OBJECTIVES: Cefiderocol is a novel siderophore cephalosporin with potent activity against multidrug-resistant Gram-negative bacteria. Here, we reported the prevalence and mechanisms of cefiderocol resistance in carbapenem-resistant Escherichia coli (CREC) in China before its clinical use. METHODS: A total of 443 non-duplicate CREC isolates collected from 67 hospitals in China (2013-2021) underwent antimicrobial susceptibility testing according to CLSI guidelines. Whole-genome sequencing, transcriptomic analysis, siderophore quantification, and targeted genetic manipulation were performed to investigate the underlying resistance mechanisms. RESULTS: Among the 443 CREC isolates, 102 (23.0%) were resistant to cefiderocol, and 34 (7.6%) showed intermediate susceptibility. Multivariable logistic regression identified ST167 lineage (OR, 3.05; 95% CI, 1.12-8.29; P = 0.028), blaNDM-5 carriage (OR, 9.04; 95% CI, 2.96-27.57; P < 0.001), and cirA truncation (OR, 49.56; 95% CI, 20.33-120.79; P < 0.001) as independent factors associated with cefiderocol resistance. Among ST167 isolates, cefiderocol-resistant isolates showed increased yersiniabactin carriage and siderophore production but comparable TonB-dependent transporter expression profiles. Phylogenetic analysis revealed that cefiderocol-resistant ST167 isolates clustered into a distinct subclade enriched with resistance-associated determinants, including a recurrent FhuA P50S substitution detected in 59/64 (92.2%) resistant isolates. Functional assays showed that the P50S substitution increased cefiderocol minimum inhibitory concentration (0.032-0.125 &#xb5;g/mL), particularly in an NDM-5-producing background (0.032-0.5 &#xb5;g/mL). CONCLUSIONS: Cefiderocol resistance is highly prevalent among high-risk ST167 CREC isolates before the clinical introduction of cefiderocol in China, highlighting the need for continued surveillance of this epidemic lineage. Cefiderocol resistance is mediated by multiple resistance determinants, and we identify the recurrent FhuA P50S substitution as a novel contributor to reduced cefiderocol susceptibility.

Antimicrobial resistance

Analyzing Meiosis in Maize.

Meiosis is central to sexual reproduction and the main source of genetic diversity in plants. Understanding how meiotic processes are regulated has direct relevance to agriculture. As meiotic recombination is the vehicle of plant breeding, gaining the ability to influence recombination patterns can accelerate crop improvement. Maize is a powerful model for studying plant meiosis, thanks to its large chromosomes, well-developed genetics, and the availability of diverse cytogenetic and molecular tools. Insights gained from maize studies can extend to other species. In this review, we describe a variety of approaches for examining meiosis and meiotic recombination in maize. Cytological techniques, including protein immunolocalization and fluorescence in situ hybridization (FISH), enable visualization of chromosome structure and behavior, as well as crossover (CO) formation. Chromatin immunoprecipitation (ChIP) is used in meiosis research to determine locations of recombination proteins, identify recombination sites, and elucidate chromatin features, such as histone modifications. Quantification of COs at specific genomic sites through pollen typing by droplet digital PCR allows precise high-resolution measurement of recombination rates. Combining cytology, protein localization, and molecular assays provides a multiscale picture of meiosis, linking molecular mechanisms to chromosome behavior and, ultimately, to genetic variation.

Journal Article

Archaic ancestry inference in imputed ancient human genomes.

When modern humans expanded from Africa into Eurasia, they interbred with archaic hominins such as Neanderthals and Denisovans. This introgression shaped human evolution, yet most insights have been gained from present-day genomes, leaving little known about how archaic variants evolved after interbreeding. Ancient genomes offer a direct view of this process, but low coverage and poor quality have limited their use. Recent advances in genotype imputation offer a way to overcome these challenges by reconstructing missing information from reference panels and recovering evolutionary signals from low-coverage data. Here, we show that imputation enables accurate detection and quantification of archaic introgression in ancient genomes, improves local archaic ancestry inference, and that regions of archaic ancestry are imputed with especially high accuracy. We further demonstrate that imputed genomes can reconstruct the trajectories of introgressed haplotypes, distinguish populations across time and geography, and identify both known and additional candidates for adaptive introgression.

Humans

Robust and accurate Bayesian inference of genome-wide genealogies for hundreds of genomes.

The Ancestral Recombination Graph (ARG), which describes the genealogical history of a sample of genomes, is a vital tool in population genomics and biomedical research. Recent advancements have substantially increased ARG reconstruction scalability, but they rely on approximations that can reduce accuracy, especially under model misspecification. Moreover, they reconstruct only a single ARG topology and cannot quantify the considerable uncertainty associated with ARG inferences. Here, to address these challenges, we introduce SINGER (sampling and inferring of genealogies with recombination), a method that accelerates ARG sampling from the posterior distribution by two orders of magnitude, enabling accurate inference and uncertainty quantification for hundreds of whole-genome sequences. Through extensive simulations, we demonstrate SINGER's enhanced accuracy and robustness to model misspecification compared to existing methods. We demonstrate the utility of SINGER by applying it to individuals of British and African descent within the 1000 Genomes Project, identifying signals of population differentiation, archaic introgression and strong support for ancient polymorphism in the human leukocyte antigen region shared across primates.

Humans

Circulating Tumor DNA Profiling Defines Risk Classification in Patients With Ewing Sarcoma: A Report From the Children's Oncology Group and the LEOPARD Study.

PURPOSE: Identification of discrete risk groups remains a high priority for patients with Ewing sarcoma (EWS). We sought to prospectively validate circulating tumor DNA (ctDNA) as a prognostic factor and develop clinical-molecular risk groups. METHODS: We conducted a prospective investigator-initiated biology study for patients with localized EWS (LEOPARD) and embedded ctDNA analysis into the North American frontline metastatic study AEWS1221. Eligible patients were younger than 50 years with newly diagnosed EWS. All patients provided a baseline blood sample for analysis, which was subjected to ultralow-pass whole-genome sequencing and hybrid capture panel sequencing for ctDNA quantification, fusion detection, and characterization of STAG2 and TP53 alterations. Serial ctDNA sequencing was conducted on a subset of patients in each study. We tested for associations between ctDNA burden and secondary genomic events, and clinical features and outcomes. RESULTS: One hundred forty patients with localized disease and 255 with metastatic disease provided evaluable pretreatment samples for ctDNA analysis. Elevated baseline ctDNA was associated with stage, tumor size, primary site, indeterminate pulmonary nodules, and metastatic pattern. Elevated pretreatment ctDNA burden was associated with inferior outcomes in patients with localized (n = 140, hazard ratio [HR] = 2.36, P = .032) and metastatic disease (n = 255, HR = 2.15, P = .001). Patients with metastatic disease and TP53 variants and/or persistent on-therapy ctDNA had dismal outcomes. Patients with localized disease, low ctDNA, small tumors, and favorable genomics had no events and constitute a novel low-risk group. Among patients with metastatic disease, those with lung-only disease, low ctDNA, and favorable genomics represent an intermediate-risk group. CONCLUSION: This study prospectively validates pretreatment ctDNA burden as prognostic in EWS. Risk groups that integrate ctDNA burden with clinical-molecular features differentiate patients with low-, intermediate-, and high-risk disease.

Journal Article

Impaired natural killer cell maturation in lung adenocarcinoma driven by FABP4 and SPON2 downregulation through disrupted lipid metabolism.

BACKGROUND: Although natural killer (NK) cells play a crucial role in antitumor immunity, the metabolic changes driving their dysfunction in lung adenocarcinoma remain poorly understood. This study investigates how these metabolic modifications impact NK cell function within the lung adenocarcinoma microenvironment. METHODS: A total of 13 pairs of lung adenocarcinoma samples were obtained from The Cancer Genome Atlas. Differential gene expression, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, and single-cell metabolic quantification analyses were used to characterize the transcriptomic, pathway, and metabolic signatures of NK cells. The developmental trajectory was reconstructed via pseudotime analysis. The fatty acid-binding protein 4 (FABP4) and spondin2 (SPON2) expression was examined using immunofluorescence (IF) and immunohistochemistry (IHC) in patients with lung adenocarcinoma. In NK cells with FABP4 downregulation, FABP4 function was analyzed using antibody-independent cell-mediated cytotoxicity assays, flow cytometry (FCM), and liquid chromatography-mass spectrometry. RESULTS: The number of NK cells was significantly decreased in the lung adenocarcinoma microenvironment. FABP4 and SPON2 expression was significantly lower in NK cells within tumor tissues than in the adjacent tissues. FABP4 expression was significantly lower in tumor tissues than in the adjacent tissues, whereas no significant difference in SPON2 expression was observed. The cytotoxic function of NK cells with decreased FABP4 levels was impaired. Non-targeted lipid metabolism analysis indicated that differentially expressed lipids in NK cells with low FABP4 levels were functionally enriched in the glycerophospholipid metabolism pathway compared to those in normal NK cells. CONCLUSIONS: The study findings present new evidence showing that low FABP4 and SPON2 gene expression may impair NK cell maturity by affecting lipid metabolism in lung adenocarcinoma. These results provide a new perspective on restoring immune function in patients with lung cancer.

FABP4