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Quantum computing-assisted validation of a conserved macrophage suppression module shared by ASFV and PEDV.

BACKGROUND: African swine fever virus (ASFV) and porcine epidemic diarrhea virus (PEDV) differ in viral biology and cellular tropism, yet both pathogens suppress macrophage-mediated immune responses in pigs. OBJECTIVE: To identify a conserved macrophage suppression module shared by ASFV and PEDV and evaluate quantum computing as an independent framework for biological network validation. METHODS: Integrated analysis of publicly available GEO datasets (GSE231435 for ASFV and GSE306895) identified 471 shared downregulated genes. A network- and multi-omics-informed 20-gene core was selected and encoded as a 20-qubit modularity-based Quadratic Unconstrained Binary Optimization (QUBO) problem. Community detection was benchmarked using the Quantum Approximate Optimization Algorithm (QAOA) on both the IBM Quantum Aer simulator and the 156-qubit IBM Fez (Heron r2) quantum processor and compared with brute-force enumeration and simulated annealing. RESULTS: A conserved macrophage suppression module shared by ASFV and PEDV was identified. For the STRING protein-protein interaction network, QAOA at circuit depth p = 3 reproduced the brute-force optimum with an approximation ratio of 1.000. In contrast, performance progressively declined in the denser co-expression network with increasing circuit depth, consistent with noise accumulation under current Noisy Intermediate-Scale Quantum (NISQ) conditions. Multi-run consensus analysis identified stable hub genes, including MMP9 and SLA-DOA, as well as genes exhibiting variable community assignments. CONCLUSION: These findings reveal a conserved macrophage suppression module shared between ASFV and PEDV and demonstrate that quantum computing can serve as an independent validation framework for biologically meaningful host-response networks. Network topology emerged as a key determinant of QAOA performance on real NISQ hardware.

Animals

Elevated Triggering Receptor Expressed on Myeloid Cells 2 Expression in Tumor-Associated Macrophages Suppresses Cytotoxic T Cell Infiltration and Facilitates Immune Escape in Colorectal Cancer.

BACKGROUND & AIMS: Emerging evidence supports a crucial role for tumor-associated macrophages in shaping the immunosuppressive tumor microenvironment. Furthermore, research has identified that the triggering receptor expressed on myeloid cells 2 has immunomodulatory functions. The present investigated the potential effect of triggering receptor expressed on myeloid cells 2 expression in tumor-associated macrophages on facilitating immune evasion in colorectal cancer. METHODS: Immunohistochemical analysis of clinical specimens, complemented by extensive data mining from The Cancer Genome Atlas, revealed a significant upregulation of triggering receptor expressed on myeloid cells 2 in colorectal cancer-associated tumor-associated macrophages, with this upregulation exhibiting a correlation with poor patient prognosis. RESULTS: Mechanistically, triggering receptor expressed on myeloid cells 2+ tumor-associated macrophages were found to drive fibroblast activation through transforming growth factor-β signaling, inducing fibroblast-activated protein-positive cancer-associated fibroblasts that secrete collagen I/III to establish dense peritumoral barriers. Spatial profiling revealed that these fibrous structures physically impede CD8+ T-cell infiltration, restricting cytotoxic lymphocytes to stromal compartments. Intriguingly, triggering receptor expressed on myeloid cells 2 deficiency enhanced the secretion of matrix metalloproteinase 13 by macrophages, thereby promoting extracellular matrix degradation and improving T-cell penetration. In vivo, Trem2-knockout mice showed a reduction in tumor growth with enhanced intratumoral CD8+ T-cell infiltration compared with wild-type controls. CONCLUSIONS: Our findings establish triggering receptor expressed on myeloid cells 2+ tumor-associated macrophages as central regulators of stromal remodeling and suggest that therapeutic targeting of the triggering receptor expressed on myeloid cells 2/transforming growth factor-β/fibroblast-activated protein pathway may overcome immune resistance in patients with colorectal cancer.

Colorectal Neoplasms

Circadian rhythms of macrophages are altered by the acidic tumor microenvironment.

Tumor-associated macrophages (TAMs) are prime therapeutic targets due to their pro-tumorigenic functions, but varying efficacy of macrophage-targeting therapies highlights our incomplete understanding of how macrophages are regulated within the tumor microenvironment (TME). The circadian clock is a key regulator of macrophage function, but how circadian rhythms of macrophages are influenced by the TME remains unknown. Here, we show that conditions associated with the TME such as polarizing stimuli, acidic pH, and lactate can alter circadian rhythms in macrophages. While cyclic AMP (cAMP) has been reported to play a role in macrophage response to acidic pH, our results indicate pH-driven changes in circadian rhythms are not mediated solely by cAMP signaling. Remarkably, circadian disorder of TAMs was revealed by clock correlation distance analysis. Our data suggest that heterogeneity in circadian rhythms within the TAM population level may underlie this circadian disorder. Finally, we report that circadian regulation of macrophages suppresses tumor growth in a murine model of pancreatic cancer. Our work demonstrates a novel mechanism by which the TME influences macrophage biology through modulation of circadian rhythms.

Tumor Microenvironment

Natural, safety immunomodulatory derivatives of lactobacillus biofilms promote diabetic wound healing by metabolically regulating macrophage phenotype and alleviating local inflammation.

INTRODUCTION: Long-term inflammatory microenvironment further impairs the healing process of diabetic wounds. Many studies have shown that Lactobacillus can regulate immune function and promote injured tissue repair. However, the immunomodulatory function and safety of Lactobacillus biofilm (LB) on wounds need further investigation. OBJECTIVES: In this present research, we proposed a "bacteria-free biofilm derivative therapy" and successfully extracted Lactobacillus biofilm derivatives (LBDs) by ultrasonic separation and filtration technology for the natural and safe treatment of diabetic wounds. METHODS: The study first cultured Lactobacillus anaerobically and extracted LBDs using ultrasound separation combined with filtration technology. LBDs were characterized via scanning electron microscopy, Concanavalin A fluorescence staining, and protein gel electrophoresis. In vivo diabetic wound model, wound closure rates were dynamically monitored, and tissue sections were analyzed using hematoxylin-eosin and immunofluorescence staining to evaluate LBDs' healing effects. An in vitro macrophage inflammation model was established, employing immunofluorescence, flow cytometry, and Western blotting techniques to explore the molecular mechanisms underlying LBDs' effects on macrophage phenotypes. Furthermore, whole-genome sequencing and proteomics of LBDs-treated macrophages were performed to further elucidate the intrinsic molecular mechanisms through which LBDs regulate macrophage phenotypes. RESULTS: LBDs were effectively extracted utilizing ultrasonic separation coupled with filtration technology. Studies revealed that LBDs modulate the systemic metabolic reprogramming in wound-site macrophages, suppress JAK-STAT1 signaling pathway, alleviate the local inflammatory microenvironment, promote neovascularization and ultimately accelerate wound healing. CONCLUSION: The LBDs retains most bioactive components of the LB. As a natural, safe and immunomodulatory agent, LBDs promote diabetic wound healing by metabolically reprogramming macrophage phenotypes and improving the local immune microenvironment, offering promising potential for regenerative applications in diabetic wound management.

Wound Healing

Colchicine attenuates cardiac hypertrophy by targeting the macrophage-driven Interleukin-6 suppression.

Hypertrophic cardiomyopathy (HCM), the most prevalent inherited cardiovascular disease, is strongly linked to progressive heart failure and sudden cardiac death (SCD). However, its underlying pathogenic mechanisms remain incompletely understood, and effective therapeutic strategies are still lacking. Here, we established two murine HCM models harboring high SCD risk-associated mutations. Single-cell RNA sequencing revealed immune activation and enhanced fibrotic remodeling in the myocardium of these models. Therefore, we hypothesized that colchicine, a widely used anti-inflammatory drug known to reduce cardiovascular events in multiple cardiac disorders, may also represent a promising therapeutic candidate for HCM. As we expected, colchicine treatment attenuated pathological remodeling in our study, as evidenced by reduced cardiomyocyte hypertrophy, decreased fibrosis, and downregulation of cardiac stress markers (Anp, Bnp) and fibrotic mediators (Ctgf, Col1a1, Col3a1). In addition, colchicine attenuated pro-inflammatory macrophage populations and suppressed IL-6 expression, thereby contributing to the preservation of cardiac function. These findings provide the first preclinical evidence that colchicine alleviates myocardial inflammation and fibrosis in HCM, underscoring its potential as a novel therapeutic strategy to reduce fibrosis, lower SCD risk, and improve patient outcomes.

Animals

Increased IL4I1 expression predicts poor survival and modulates the immune microenvironment in acute myeloid leukemia.

BACKGROUND: The immunometabolic enzyme Interleukin-4-induced-1 (IL4I1) is implicated in cancer pathogenesis, yet its specific function and clinical relevance in acute myeloid leukemia (AML) remain unclear. METHODS: Comparative analysis of IL4I1 mRNA levels between AML patients and normal controls was performed using the Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases. The Kaplan&#x2013;Meier survival analysis was conducted to evaluate the prognostic value of IL4I1. Functional insights were derived from analyses of differentially expressed genes (DEGs), Gene Set Enrichment Analysis (GSEA), and Gene Ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. Immune infiltration was evaluated using the ssGSEA, ESTIMATE, quanTIseq and single-cell RNA sequencing (scRNA-seq) analysis. Finally, in vitro and in vivo functional experiments were perfromed to explore the impact of IL4I1 on AML progression and immunoregulation. RESULTS: IL4I1 expression was significantly elevated in AML compared to normal controls (p&#x2009;=&#x2009;0.0004) and associated with poorer overall survival (p&#x2009;=&#x2009;0.003). Bioinformatic analysis revealed that IL4I1 was linked to immune-related pathways&#x2014;including humoral immune response, leukocyte interactions, and chemokine signaling&#x2014;and to cellular amino acid metabolism. Its expression correlated with immune cell infiltration and checkpoint molecule expression. Experimentally, IL4I1 promoted leukemia cell proliferation in vitro and in vivo (p&#x2009;<&#x2009;0.05). Furthermore, silencing IL4I1 suppressed M2 macrophage polarization and reduced secretion of inflammatory factors (p&#x2009;<&#x2009;0.05). CONCLUSIONS: IL4I1 may serve as a potential biomarker for poor prognosis and an attractive target for immune-based therapeutic interventions in AML.

Humans

tRNA m1A modification orchestrates STING translation in macrophages to enhance antitumor immunity and CAR-macrophage immunotherapy.

Tumor-associated macrophages (TAMs) play crucial roles in tumor progression. However, the mechanisms underlying the posttranscriptional regulation of TAMs remain largely unknown. Here, we demonstrated that Trmt61a, the "writer" enzyme of tRNA N1-methyladenosine (m1A) modification, is highly expressed in proinflammatory macrophages in tumor microenvironment. We generated conditional knockout (KO) mice for Trmt61a and observed that Trmt61a deletion in macrophages significantly promoted tumor growth. Mechanistically, we identified that m1A maintains the translation of STING, enhances STING-TBK1-IFN-&#x3b2; signaling in macrophages and therefore suppresses tumor cell growth. We further generated TRMT61A-overexpressing human iPSC-derived CAR-macrophage and demonstrated that human TRMT61A effectively promoted antitumor CAR-macrophage therapy in vivo. Collectively, our findings reveal a novel regulatory mechanism of tRNA m1A modification in macrophages, highlighting the antitumor therapeutic potential of targeting tRNA m1A modification in macrophages.

Animals

RUNX3: a regulator of macrophage apoptosis with positive prognostic impact in sepsis.

BACKGROUND: Sepsis, a life-threatening condition, remains a leading cause of mortality globally. Transcription factors (TFs) play a pivotal role in its pathogenesis. RUNX3, a member of the RUNX family, has been implicated in immune regulation, but its function in sepsis remains unclear. OBJECTIVE: To determine whether RUNX3 expression is altered in sepsis and associated with patient prognosis, and to investigate its function and potential transcriptional regulatory targets in macrophages. METHODS: We analyzed RNA-seq data from sepsis patients to identify differentially expressed TFs and examined the prognostic impact of RUNX3 by Kaplan-Meier survival analysis. RUNX3 was stably overexpressed in RAW264.7 macrophages, and cell proliferation and apoptosis were assessed by EdU and flow cytometry assays. RNA-seq of RUNX3-overexpressing cells was performed to identify potential transcriptional regulatory targets, a subset of which was validated by RT-qPCR. RESULTS: RUNX3 expression was downregulated in sepsis patients, and low RUNX3 expression was associated with poor prognosis. RUNX3 overexpression promoted proliferation and inhibited apoptosis in RAW264.7 cells. Integrating RNA-seq with public RUNX3 binding data identified 89 potential transcriptional regulatory targets, among which Tgfbr3, Tgfbi, Il2rb, Gbp2, Gzmb, and Ptgds were confirmed as RUNX3-responsive by RT-qPCR. High expression of these targets was associated with favorable prognosis in sepsis patients. CONCLUSION: RUNX3 is closely associated with the prognosis of sepsis, and its overexpression promotes proliferation and suppresses apoptosis in macrophages, potentially by regulating downstream target genes, providing a novel perspective on sepsis pathogenesis.

Apoptosis

p53 enhances DNA repair and suppresses cytoplasmic chromatin fragments and inflammation in senescent cells.

Genomic instability and inflammation are distinct hallmarks of aging, but the connection between them is poorly understood. Here we report a mechanism directly linking genomic instability and inflammation in senescent cells through a mitochondria-regulated molecular circuit involving p53 and cytoplasmic chromatin fragments (CCF) that are enriched for DNA damage signaling marker &#x3b3;H2A.X. We show that p53 suppresses CCF accumulation and its downstream inflammatory phenotype. p53 activation suppresses CCF formation linked to enhanced DNA repair and genome integrity. Activation of p53 in aged mice by pharmacological inhibition of MDM2 reverses transcriptomic signatures of aging and age-associated accumulation of monocytes and macrophages in liver. Mitochondrial ablation in senescent cells suppresses CCF formation and activates p53 in an ATM-dependent manner, suggesting that mitochondria-dependent formation of &#x3b3;H2A.X&#x2009;+&#x2009;CCF dampens nuclear DNA damage signaling and p53 activity. These data provide evidence for a mitochondria-regulated p53 signaling circuit in senescent cells that controls DNA repair, genome integrity, and senescence- and age-associated inflammation, with relevance to therapeutic targeting of age-associated disease.

Animals

Mycobacterium tuberculosis MEM39 (Rv1977) hijacks host aldolase A (ALDOA) to subvert immunometabolism to facilitate bacterial intracellular survival.

Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), is the leading cause of infectious disease-related death. As a major intracellular pathogen, Mtb can escape clearance by the immune system, but the underlying molecular mechanisms remain incompletely elucidated. Specific genomic regions of deletion (RD)-encoded proteins in virulent Mtb H37Rv have been implicated in modulating pathogenicity and immunity. Here, we report a novel RD15-encoding protein, Rv1977 (a mycobacterial cell wall protein with a size of 39&#x2009;kDa, named MEM39), which facilitates Mtb survival in macrophages. The survival of the Mtb H37Rv MEM39-deficient strain is reduced in both macrophage and murine infection models. Furthermore, the mycobacterial MEM39 protein binds fructose-diphosphate aldolase A (ALDOA), a key enzyme of glycolysis, thereby impairing ALDOA enzyme activity, disrupting macrophage metabolite flux, and reducing lactate production. The MEM39-ALDOA interaction also suppresses lysosomal acidification; reduces NLRP3 inflammasome activation and the production of proinflammatory cytokines (TNF-&#x3b1;, IL-6 and IL-1&#x3b2;); and thereby promotes bacterial survival within macrophages. Disruption of the interaction between MEM39-ALDOA and a cell-penetrating synthetic peptide (VLARYASICQ) significantly suppressed Mtb survival by restoring lactate production, lysosome acidification and proinflammatory cytokine production in both macrophage and mouse infection models. These findings revealed that mycobacterial MEM39 negatively regulates host immune defense through reprogramming ALDOA-mediated glycolysis in macrophages, thereby forming a "mycobacterial MEM39 virulence factor-glycolysis metabolism-immunity" regulatory axis. Targeting MEM39 or the MEM39-ALDOA interaction interface holds promise as a new therapeutic strategy against tuberculosis.

Mycobacterium tuberculosis

BET inhibition blunts antibody production and macrophage-mediated fibrosis to restore lung function in murine cGVHD.

Chronic graft-versus-host disease (cGVHD) significantly contributes to late mortality after allogeneic stem cell transplantation, with bronchiolitis obliterans syndrome (BOS) being a particularly lethal and treatment-resistant complication despite available therapies. Bromodomain and extraterminal (BET) proteins are epigenetic readers driving inflammatory transcriptional programs across multiple cell types. We hypothesized that BET inhibition would suppress inflammatory T and B cells and decrease macrophage polarization to a profibrotic phenotype, alleviating disease. In an established BOS cGVHD model, BET inhibition reduced germinal center (GC) formation and responses through a reduction of the CXCL13:CXCR5 axis and inflammatory T follicular helper/GC B cells in the spleen, along with a reduction in plasma cell infiltration within the lung. Mice with cGVHD had elevated pathogenic immunoglobulin G1 (IgG1) and IgM levels, both in circulation and deposited on lung tissue, which were attenuated under BET inhibition. Single-cell RNA-sequencing analysis revealed distinct cell states in the BOS lung vs control. In cGVHD mice, gene set enrichment analysis revealed the upregulation of profibrotic Arginase1 and Tgfb1 expression in alveolar macrophages (AM) and interstitial macrophages (IM), which was significantly reduced with BET inhibition. Furthermore, BET inhibition targeted lung-infiltrating M2 macrophages through the selective depletion of CD206+Fc&#x3b3;R+ IM and AM, ultimately resulting in reduced collagen deposition and improved lung function. Our findings reveal a previously unrecognized mechanistic axis of BET regulation during cGVHD fibrosis and highlight BET inhibition as a promising therapeutic strategy.

Animals

Next-generation macrophage engineering in cancer therapy: From TAM reprogramming to CAR-macrophages.

Macrophages are central regulators of the tumor microenvironment (TME), shaping immune suppression, angiogenesis, metabolism, and therapeutic resistance in solid cancers. While early strategies sought to deplete tumor-associated macrophages (TAMs) or block monocyte recruitment, limited efficacy and compensatory mechanisms revealed the need for functional reprogramming rather than elimination. Recent advances in viral vectors, CRISPR-Cas genome editing, and RNA-based delivery platforms have enabled precise genetic modification of macrophages, giving rise to chimeric antigen receptor macrophages (CAR-Ms) and related engineered products. Beyond antigen targeting, effective macrophage engineering requires stabilization of pro-inflammatory identity, resistance to tumor-induced repolarization, metabolic reinforcement, and integration of checkpoint modulation pathways. This review synthesizes current strategies across DNA, mRNA, and siRNA-based platforms, highlighting convergent design principles that connect TAM reprogramming with CAR-M development. We discuss reshaping phagocytosis checkpoints, metabolic and transcriptional stabilization, cytokine augmentation, and synthetic receptor architecture, emphasizing combinatorial and context-aware engineering, while proposing new candidate gene targets. Engineered macrophages are thus evolving from simple effector cells into programmable immune coordinators capable of converting immunologically "cold" tumors into inflamed, therapy-responsive niches.

CAR-M

Inflammatory pathways and immune dysregulation in pediatric postoperative septic shock: A study integrating transcriptomics, machine learning and molecular docking.

This study elucidates the molecular and immune regulatory mechanisms of pediatric postoperative septic shock. Transcriptomic data were obtained from the Gene Expression Omnibus database. Differentially expressed genes were identified using the limma package, and gene co-expression modules were constructed using Weighted Gene Co-expression Network Analysis. Functional enrichment was performed via gene set enrichment analysis, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes analyses. Immune cell infiltration was assessed using ESTIMATE and CIBERSORT. Mendelian randomization was applied to explore causal relationships between gene expression and septic shock. Feature genes were selected using machine learning algorithms, and a diagnostic nomogram model was constructed. Finally, molecular docking analysis was performed to screen and evaluate the binding affinity of traditional Chinese medicine monomers to core target proteins. A total of 1331 differentially expressed genes were identified, and the turquoise module was strongly correlated with septic shock. Enrichment analysis revealed significant activation of IL-6/JAK/STAT3, TNF-&#x3b1;/NF-&#x3ba;B, and PI3K/Akt/mTOR pathways. Immune infiltration analysis indicated suppressed immune scores and imbalances in neutrophils, macrophages, T cells, and B cells. Mendelian randomization confirmed causal associations for 6 genes, including PIM3. The predictive model based on feature genes demonstrated high diagnostic performance. Molecular docking suggested that quercetin and astramembrannin I could stably bind PIM3. This study systematically identified core genes, dysregulated immune pathways, and candidate small-molecule interventions in pediatric septic shock, providing novel insights for early diagnosis and targeted therapy.

Humans

Spatial Mapping of the Precancer-to-Cancer Transition in Breast and Prostate.

UNLABELLED: Breast and prostate cancers are both hormone-driven adenocarcinomas that undergo analogous invasion programs. Using lightsheet microscopy on intact tumors, we identified transitional junctions between precancerous and invasive regions. We then developed a multimodal serial-section workflow integrating volumetric reconstruction with spatial transcriptomics. Analysis of 319 spatial assays from 51 cases revealed gene expression features and novel structural insights defining the shift from precancer to invasive disease. In breast cancer, loss of MGP and PLAT was associated with invasive transition and promoted tumorigenesis in functional assays. In prostate cancer, GDF15, ALDH1A3, ANPEP, and FASN were upregulated along invasive progression, and their knockdown in PC-3 cells suppressed proliferation and migration. Enrichment of tumor-associated macrophages (SPP1+ and MS4A6A+) along non-triple-negative breast cancer breast cancer transitions highlights immune involvement as a potential driver of invasiveness. SIGNIFICANCE: Our method of defining precise spatial locations of invasive transition allows for the direct interrogation of transition drivers, presenting new therapeutic targets for the two most prevalent cancers and providing a framework for studying spatially defined mechanisms of tumor progression. See related commentary by Jing and Li, p. 1720.

Humans

Modulation of Mettl5 alleviates airway allergy by regulating the epigenetic profile of M2 macrophages.

M2 macrophages (M2 cells) are known to be involved in both Th2 responses and immune regulation. However, the underlying mechanisms remain unclear. Functional abnormalities in macrophages are associated with airway allergy (AA). The objective of this study was to investigate the role of methyltransferase-like 5 (Mettl5) in macrophages and its potential to alleviate AA. In this study, an airway allergy (AA) mouse model was established using dust mite extracts (DME) as the specific antigen. M2 cells were collected from mice with and without AA. The role of Mettl5 in modulating the immune activities of M2 cells was assessed using both epigenetic and immunological approaches. We found that Mettl5 levels were elevated in airway M2 cells from mice with AA. The presence of Mettl5 in airway M2 cells was positively correlated with airway Th2 polarization in these mice. Airway M2 cells from AA mice exhibited impaired immune-suppressive function, which was resolved by ablating the Mettl5 gene in macrophages. Mettl5 was responsible for the hypermethylation of the Il10 promoter in airway M2 cells of AA mice. Exposure to DME induced Mettl5, which in turn recruited USP21 to deubiquitinate GATA3, thereby boosting IL-4 expression in M2 cells. Inhibiting Mettl5 restored the immune-suppressive capacity of airway M2 cells and mitigated experimental AA. In conclusion, Mettl5 plays a critical role in subverting the immune-regulatory capacity and enhancing IL-4 expression in M2 cells. Inhibition of Mettl5 can mitigate experimental AA by restoring the immune-regulatory functions of M2 cells.

Animals

The mechanism of malignant progression in extramammary Paget's disease (EMPD): hallmarks of EMPD.

The pathogenesis of cancer is characterized by the acceleration of tumor growth, inhibition of tumor suppression, genetic and epigenetic alteration, lubricative transformation and tumor microenvironment. Extramammary Paget's disease (EMPD) is a rare skin cancer that originates from apocrine glands in genital and axillary area. Although the pathogenesis of EMPD is still poorly understood, increasing evidence reveals that the mechanism of EMPD progression is regulated by the acquired ability of EMPD cells and tumor microenvironment. HER2/PI3K/AKT signaling and hormone receptor pathways are activated. Whereas tumor mutation burden is low, numerous driver genes such as ERBB2 and PIK3CA are detected. Tumor evolution in EMPD is characterized by high genetic intratumor heterogeneity with shared background factors. Tumor microenvironment in EMPD promotes immune evasion through the reduction of reduced CD4&#x2009;+&#x2009;and CD8&#x2009;+&#x2009;T cells and the increase of Treg cells and CD163&#x2009;+&#x2009;macrophages. Enhanced Warburg effect and S. aureus contribute to the suppression of antitumor immunity. This review focuses on the mechanism of malignant progression in EMPD (hallmarks of EMPD).

Genome mutation

MCT4-dependent lactate secretion suppresses antitumor immunity in LKB1-deficient lung adenocarcinoma.

Inactivating STK11/LKB1 mutations are genomic drivers of primary resistance to immunotherapy in KRAS-mutated lung adenocarcinoma (LUAD), although the underlying mechanisms remain unelucidated. We find that LKB1 loss results in enhanced lactate production and secretion via the MCT4 transporter. Single-cell RNA profiling of murine models indicates that LKB1-deficient tumors have increased M2 macrophage polarization and hypofunctional T&#xa0;cells, effects that could be recapitulated by the addition of exogenous lactate and abrogated by MCT4 knockdown or therapeutic blockade of the lactate receptor GPR81 expressed on immune cells. Furthermore, MCT4 knockout reverses the resistance to PD-1 blockade induced by LKB1 loss in syngeneic murine models. Finally, tumors from STK11/LKB1 mutant LUAD patients demonstrate a similar phenotype of enhanced M2-macrophages polarization and hypofunctional T&#xa0;cells. These data provide evidence that lactate suppresses antitumor immunity and therapeutic targeting of this pathway is a promising strategy to reversing immunotherapy resistance in STK11/LKB1 mutant LUAD.

Animals

Novel Genetic Loci in Early-Onset Gout Derived From Whole-Genome Sequencing of an Adolescent Gout Cohort.

OBJECTIVE: Mechanisms underlying the adolescent-onset and early-onset gout are unclear. This study aimed to discover variants associated with early-onset gout. METHODS: We conducted whole-genome sequencing in a discovery adolescent-onset gout cohort of 905 individuals (gout onset 12 to 19 years) to discover common and low-frequency single-nucleotide variants (SNVs) associated with gout. Candidate common SNVs were genotyped in an early-onset gout cohort of 2,834 individuals (gout onset &#x2264;30 years old), and meta-analysis was performed with the discovery and replication cohorts to identify loci associated with early-onset gout. Transcriptome and epigenomic analyses, quantitative real-time polymerase chain reaction and RNA sequencing in human peripheral blood leukocytes, and knock-down experiments in human THP-1 macrophage cells investigated the regulation and function of candidate gene RCOR1. RESULTS: In addition to ABCG2, a urate transporter previously linked to pediatric-onset and early-onset gout, we identified two novel loci (Pmeta < 5.0 &#xd7; 10-8): rs12887440 (RCOR1) and rs35213808 (FSTL5-MIR4454). Additionally, we found associations at ABCG2 and SLC22A12 that were driven by low-frequency SNVs. SNVs in RCOR1 were linked to elevated blood leukocyte messenger RNA levels. THP-1 macrophage culture studies revealed the potential of decreased RCOR1 to suppress gouty inflammation. CONCLUSION: This is the first comprehensive genetic characterization of adolescent-onset gout. The identified risk loci of early-onset gout mediate inflammatory responsiveness to crystals that could mediate gouty arthritis. This study will contribute to risk prediction and therapeutic interventions to prevent adolescent-onset gout.

Humans