Chromosomal instability drives metastasis through a cytosolic DNA response

STING and metabolism-related diseases: Roles, mechanisms, and applications

The stimulator of interferon genes (STING) pathway plays a critical role in innate immunity, acting as a central mediator that links cytosolic DNA sensing to inflammatory signaling. STING not only responds to cellular metabolic states but also actively regulates key metabolic processes, including glycolysis, lipid metabolism, and redox balance. This bidirectional interaction underscores the existence of a dynamic feedback mechanism between STING signaling and metabolic pathways, which is essential for maintaining cellular homeostasis. This review provides a comprehensive analysis, beginning with an in-depth overview of the classical STING signaling pathway, followed by a detailed examination of its reciprocal regulation of various metabolic pathways. Additionally, it explores the role and mechanisms of STING signaling in metabolic disorders, including obesity, diabetes, and atherosclerosis. By integrating these insights into the mutual regulation between STING and its metabolism, novel therapeutic strategies targeting this pathway in metabolic diseases have been proposed.

Inhibition of the cGAS-STING pathway: contributing to the treatment of cerebral ischemia-reperfusion injury

The cGAS-STING pathway plays an important role in ischemia-reperfusion injury in the heart, liver, brain, and kidney, but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically reviewed. Here, we outline the components of the cGAS-STING pathway and then analyze its role in autophagy, ferroptosis, cellular pyroptosis, disequilibrium of calcium homeostasis, inflammatory responses, disruption of the blood-brain barrier, microglia transformation, and complement system activation following cerebral ischemia-reperfusion injury. We further analyze the value of cGAS-STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple mechanisms. Inhibition of the cGAS-STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury.

Characterizing chromosome instability reveals its association with lipid-associated macrophages and clonal evolution of lymph node metastasis in esophageal squamous cell carcinoma

Esophageal cancer is an aggressive cancer, and metastasis is one of the major factors contributing to treatment failure, leading to poor clinical outcomes. Chromosome instability (CIN) is frequently observed in esophageal squamous cell carcinoma (ESCC). However, the functional impact of CIN is not well studied in ESCC metastasis. We aim to study the role and underlying mechanisms of CIN in lymph node (LN) metastasis. Integrated analysis was performed using single-cell RNA sequencing data with matched whole-exome sequencing in primary ESCC, genomic sequencing in ESCC organoids and clinical specimens, and spatial protein profiling to characterize CIN and relevant tumor immune microenvironment (TIME) associated with LN metastasis. CIN in primary ESCC is significantly associated with LN metastasis at diagnosis, particularly in those patients with homologous recombination deficiency and use of alternative end joining (alt-EJ). Primary CIN ESCC exhibited increased epithelial-mesenchymal transition (EMT), hypoxia, angiogenesis, RNA metabolism, and heat stress, associated with a strong metastatic potential. Although CIN ESCC has elevated neoantigen loads, its TIME was enriched for immunosuppressive lipid-associated tumor-associated macrophages (LA-TAMs). Secreted phosphoprotein 1 (SPP1) plays a key role in mediating the communications of CIN ESCC cells and LA-TAMs. In LN metastases, structural CIN (sCIN) with retrotransposon insertion and reactivation is important for ESCC clonal evolution and cell proliferation, associated with increased LA-TAMs infiltration and poor overall patient survival. ESCC with high CIN has a strong metastatic potential. Our findings reveal a novel link between error-prone DSB repair pathways and LA-TAMs through CIN in LN metastasis.

Demystifying the cGAS-STING pathway: precision regulation in the tumor immune microenvironment

The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway serves as an immune sentinel for cytosolic DNA, recognizing double-stranded DNA (dsDNA) derived from abnormally localized nuclear DNA or mitochondrial DNA (mtDNA), and plays a pivotal role in innate immune responses and tumor immune surveillance. Conventional antitumor therapies induce genomic instability and mitochondrial stress, leading to the release of nuclear DNA and mtDNA into the cytosol, thereby activating the cGAS-STING pathway. This activation triggers the production of type I interferons (IFN-I) and pro-inflammatory cytokines, which reshape the tumor immune microenvironment (TIME). However, the complexity of TIME reveals a "double-edged sword" effect of cGAS-STING signaling: while it activates antitumor immune responses, it also promotes immune escape and metastasis through the regulation of immunosuppressive cells and stromal components. This review comprehensively delineates the differential regulatory mechanisms of the pathway within TIME constituents, highlighting its multifaceted roles in tumor immunity. Furthermore, it reviews recent advances and challenges in targeting the cGAS-STING pathway for cancer immunotherapy, with the aim of advancing cGAS-STING signaling modulation as a key therapeutic strategy to reprogram TIME and overcome immunosuppression in antitumor treatment.

Potentiating cancer immunotherapies with modular albumin-hitchhiking nanobody-STING agonist conjugates

The enhancement of antitumour immunity via agonists of the stimulator of interferon genes (STING) pathway is limited by pharmacological barriers. Here we show that the covalent conjugation of a STING agonist to anti-albumin nanobodies via site-selective bioconjugation chemistries prolongs the circulation of the agonist in the blood and increases its accumulation in tumour tissue, stimulating innate immune programmes that increased the infiltration of activated natural killer cells and T cells, which potently inhibited the growth of mouse tumours. The technology is modular, as demonstrated by the recombinant integration of a second nanobody domain targeting programmed death-ligand 1 (PD-L1), which further increased the accumulation of the agonist in tumours while blocking immunosuppressive PD-1/PD-L1 interactions. The bivalent nanobody-STING agonist conjugate stimulated robust antigen-specific T-cell responses and long-lasting immunological memory and conferred enhanced therapeutic efficacy. It was also effective as a neoadjuvant treatment to adoptive T-cell therapy. As a modular approach, hitchhiking STING agonists on serum albumin may serve as a broadly applicable strategy for augmenting the potency of systemically administered cancer immunotherapies.

Advances in nanoplatform-based multimodal combination therapy activating STING pathway for enhanced anti-tumor immunotherapy

Activation of the cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes (STING) has great potential to promote antitumor immunity. As a major effector of the cell to sense and respond to the aberrant presence of cytoplasmic double-stranded DNA (dsDNA), inducing the expression and secretion of type I interferons (IFN) and STING, cGAS-STING signaling pathway establishes an effective natural immune response, which is one of the fundamental mechanisms of host defense in organisms. In addition to the release of heterologous DNA due to pathogen invasion and replication, mitochondrial damage and massive cell death can also cause abnormal leakage of the body's own dsDNA, which is then recognized by the DNA receptor cGAS and activates the cGAS-STING signaling pathway. However, small molecule STING agonists suffer from rapid excretion, low bioavailability, non-specificity and adverse effects, which limits their therapeutic efficacy and in vivo application. Various types of nano-delivery systems, on the other hand, make use of the different unique structures and surface modifications of nanoparticles to circumvent the defects of small molecule STING agonists such as fast metabolism and low bioavailability. Also, the nanoparticles are precisely directed to the focal site, with their own appropriate particle size combined with the characteristics of passive or active targeting. Herein, combined with the cGAS-STING pathway to activate the immune system and kill tumor tissues directly or indirectly, which help maximize the use of the functions of chemotherapy, photothermal therapy(PTT), chemodynamic therapy(CDT), and radiotherapy(RT). In this review, we will discuss the mechanism of action of the cGAS-STING pathway and introduce nanoparticle-mediated tumor combination therapy based on the STING pathway. Collectively, the effective multimodal nanoplatform, which can activate cGAS-STING pathway for enhanced anti-tumor immunotherapy, has promising avenue clinical applications for cancer treatment.

Longitudinal and multisite sampling reveals mutational and copy number evolution in tumors during metastatic dissemination

To understand genetic evolution in cancer during metastasis, we analyzed genomic profiles of 3,732 cancer patients in whom several tumor sites were longitudinally biopsied. During distant metastasis, tumors were observed to accumulate copy number alterations (CNAs) to a much greater degree than mutations. In particular, the development of whole genome duplication was a common event during metastasis, emerging de novo in 28% of patients. Loss of 9p (including CDKN2A) developed during metastasis in 11% of patients. To a lesser degree, mutations and allelic loss in human leukocyte antigen class I and other genes associated with antigen presentation also emerged. Increasing CNA, but not increasing mutational load, was associated with immune evasion in patients treated with immunotherapy. Taken together, these data suggest that CNA, rather than mutational accumulation, is enriched during cancer metastasis, perhaps due to a more favorable balance of enhanced cellular fitness versus immunogenicity.

CINs of the cytoplasm: dissecting dsRNA signaling in chromosomal instability

Chromosomal instability (CIN), a pervasive feature of cancer, promotes tumor evolution and inflammatory signaling, yet its influence on innate immune sensing remains incompletely understood. Ruptured micronuclei, a direct byproduct of CIN arising from missegregated chromosomes, expose out-of-context double-stranded DNA that engages the cGAS-STING pathway. In their recent study, Sasaki et al. show that micronuclei are also a source of immunogenic double-stranded RNA (dsRNA), triggering MAVS-dependent type I interferon responses independently of STING. The authors show that micronuclei undergo aberrant transcription, producing dsRNA from nonexonic, transcriptionally accessible loci, with many species localizing near interferon-stimulated genes. This work suggests a feedforward loop in which type I interferon signaling reinforces its own activation through transcriptional dysregulation. Using MPS1 inhibition to induce acute CIN, the authors show that MAVS signaling promotes MHC Class I expression and immune cell recruitment. These findings reposition CIN as a dual trigger of innate immunity through cytoplasmic DNA and RNA sensing. Future work should define how these pathways integrate in the context of chronic CIN and evaluate strategies to target DNA and RNA sensing in immune-edited tumors.

Blood Biomarker-Based Predictive Indicator for Liver Metastasis in Alpha-Fetoprotein-Producing Gastric Cancer and Multi-Omics Tumor Microenvironment Insights

Alpha-fetoprotein-producing gastric cancer (AFPGC) is a rare but highly aggressive subtype of gastric cancer. Patients with AFPGC are at high risk of liver metastasis, and the tumor microenvironment (TME) is complex. A multicenter retrospective study is conducted from January 2011 to December 2021 and included 317 AFPGC patients. Using a multivariable logistic regression model, a nomogram for predicting liver metastasis is built. By combining AFP and the neutrophil-lymphocyte ratio (NLR), we developed a novel and easily applicable predictive indicator, termed ANLiM score, for liver metastasis in AFPGC. An integrated multi-omics analysis, including whole-exome sequencing and proteomic analysis, is conducted and revealed an immunosuppressive TME in AFPGC with liver metastasis. Single-cell RNA sequencing and multiplex immunofluorescence identified the potential roles of tumor-associated neutrophils and tertiary lymphoid structures in shaping the immune microenvironment. These findings are validated in a real-world cohort receiving anti-programmed cell death 1 (anti-PD-1) therapy, which showed concordant effectiveness. In addition, the ANLiM score is also identified as a promising biomarker for predicting immunotherapy efficacy. Overall, a blood biomarker-based predictive indicator is developed for liver metastasis and immunotherapy response in AFPGC. The findings on immune microenvironmental alterations for AFPGC with liver metastasis provide new insights for optimizing immunotherapy strategies.

Targeting DNA helicase CMG complex and NFκB2-driven drug-resistant transcriptional axis to effectively treat KRASG12D-mutated pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is a devastating malignancy with a 5-year overall survival (OS) rate of approximately 12%. More than 90% of PDAC patients harbor oncogenic mutations in the Kirsten rat sarcoma viral homolog (KRAS) gene. MRTX1133 (MRTX), a novel inhibitor of KRASG12D (the most common KRAS mutation found in pancreatic and colon cancers) has shown promise as a therapeutic agent. To address reported resistance to MRTX, we adapted our anti-leukemia co-targeting strategy and evaluated a combination of MRTX and Bedaquiline (BED), an FDA-approved inhibitor of mitochondrial ATP production, in in vitro human PDAC models. The combination of MRTX and BED demonstrated enhanced cytotoxic effects by disrupting all 11 genes within the DNA helicase family (CMG complex: CDC45-MCM-GINS), which are essential for initiating DNA replication and regulating cell cycle progression. Notably, real-world data analysis from Caris Life Sciences and NCI-TCGA database revealed that low transcriptomic expression of the DNA helicase CMG complex was significantly associated with prolonged survival (e.g., low CDC45 expression and low GINS2 expression with greater than 8 months longer overall survival) in PDAC patients with KRASG12 mutations (N = 9,717; P < 0.00001). However, this combination therapy also triggered strong pro-survival nuclear reprogramming. This effect was mediated by significant genetic activation of an NFκB2-DDIT (DNA damage-induced transcript) axis, which supported tumor chromosomal integrity and DNA repair mechanisms. To overcome NFκB2-driven resistance mechanisms, we explored a triple-targeting strategy that addresses metabolic and genomic plasticity in addition to actively intercepting cell division. This approach combines MRTX1133, Bedaquiline, and the NFκB2 inhibitor SN52, offering a novel therapeutic avenue to treat aggressive pancreatic cancer and potentially improve patient outcomes.

DNA repair and the contribution to chemotherapy resistance

The DNA damage response comprises a set of imperfect pathways that maintain cell survival following exposure to DNA damaging agents. Cancers frequently exhibit DNA repair pathway alterations that contribute to their intrinsic genome instability. This, in part, facilitates a therapeutic window for many chemotherapeutic agents whose mechanisms of action often converge at the generation of a double-strand DNA break. The development of therapy resistance occurs through countless molecular mechanisms that promote tolerance to DNA damage, often by preventing break formation or increasing repair capacity. This review broadly discusses the DNA damaging mechanisms of action for different classes of chemotherapeutics, how avoidance and repair of double-strand breaks can promote resistance, and strategic directions for counteracting therapy resistance.

ENPP1 inhibitor with ultralong drug-target residence time as an innate immune checkpoint blockade cancer therapy

Only one in five patients is estimated to respond to immune checkpoint inhibitors, which primarily target adaptive immunity. To date, no FDA-approved immunotherapies directly activate the innate anti-cancer immunity-an essential driver of lymphocyte recruitment and potentiator of responses to existing cancer immunotherapies. ENPP1, the dominant hydrolase that degrades extracellular cGAMP and suppresses downstream STING-mediated innate immune signaling, has emerged as a promising therapeutic target. However, existing ENPP1 inhibitors have been optimized for prolonged systemic residence time rather than effective target inhibition within tumors. Here, we report the characterization of STF-1623, a highly potent ENPP1 inhibitor with an exceptionally long tumor residence time despite rapid systemic clearance, enabled by its high ENPP1 binding affinity and slow dissociation rate. We show that membrane-bound ENPP1 on tumor cells, not the abundant soluble ENPP1 in serum, drives tumor progression. Consequently, STF-1623 unleashes anti-tumor immunity and synergizes with ionizing radiation, anti-PD-L1 and anti-PD-1, and a DNA damaging agent to produce robust anti-tumor and anti-metastatic effects across multiple syngeneic mouse tumor models, all without detectable toxicity. Conceptually, this work establishes that a noncovalent small molecule inhibitor of ENPP1 with ultralong drug-target engagement offers a safe and precise strategy to activate STING within tumors, fulfilling an unmet need of innate immunotherapies in cancer.

Tumor break load quantitates structural variant-associated genomic instability with biological and clinical relevance across cancers

While structural variants (SVs) are a clear sign of genomic instability, they have not been systematically quantified per patient since declining costs have only recently enabled large-scale profiling. Therefore, the biological and clinical impact of high numbers of SVs in patients is unknown. We introduce tumor break load (TBL), defined as the sum of unbalanced SVs, as a measure for SV-associated genomic instability. Using pan-cancer data from TCGA, PCAWG, and CCLE, we show that a high TBL is associated with significant changes in gene expression in 26/31 cancer types that consistently involve upregulation of DNA damage repair and downregulation of immune response pathways. Patients with a high TBL show a higher risk of recurrence and shorter median survival times for 5/15 cancer types. Our data demonstrate that TBL is a biologically and clinically relevant feature of genomic instability that may aid patient prognostication and treatment stratification. For the datasets analyzed in this study, TBL has been made available in cBioPortal.

Targeting vulnerabilities of aneuploid cells for cancer therapy

Aneuploidy is a common feature of cancer that drives tumor evolution, but it also creates cellular vulnerabilities that might be exploited therapeutically. Recent advances in genomic technologies and experimental models have uncovered diverse cellular consequences of aneuploidy, revealing dependencies on mitotic regulation, DNA replication and repair, proteostasis, metabolism, and immune interactions. Harnessing aneuploidy for precision oncology requires the combination of genomic, functional, and clinical studies that will enable translation of our improved understanding of aneuploidy to targeted therapies. In this review we discuss approaches to targeting both highly aneuploid cells and cells with specific common aneuploidies, summarize the biological underpinning of these aneuploidy-induced vulnerabilities, and explore their therapeutic implications.

Single-cell chromosome and bulk transcriptome analysis as a diagnostic tool to differentiate between localized and metastatic pheochromocytoma and sympathetic paraganglioma

Approximately 10-20% of patients with pheochromocytoma or sympathetic paraganglioma (PPGL) develop metastatic disease, most often as metachronous lesions. Unfortunately, there is a lack of accurate biomarkers that can predict the biologic behavior of a PPGL at the initial diagnosis. We investigated tumor samples from patients with PPGL and a diagnosis of either localized or metastatic disease with synchronous or metachronous metastases and performed a comprehensive molecular analysis through application of single-cell whole-genome sequencing and bulk transcriptome analysis, including variant detection analysis of RNA sequences. We found that PPGL displayed complex karyotypes with recurrent aneuploidies and substantial cell-to-cell karyotype variability, indicating ongoing chromosomal instability (CIN) in both localized and metastatic tumors. Transcriptome analysis on the other hand revealed several differences between localized and metastatic PPGL including TNFα and TGFβ signaling in metastatic PPGL that were already detectable in primary tumor samples of initially non-metastatic-appearing PPGLs that developed metachronous metastases. Altogether our findings indicate that while localized and metastatic PPGL in general have comparable genomic landscapes, they do show transcriptional differences that are already detectable in primary tumor PPGL before development of metastases. This finding could provide an important tool for improvement of patient stratification at initial diagnosis.

Cancer cells' chamber of secrets: the link between micronuclei, chromothripsis and malignancy

Micronuclei exhibit defective proteomes rendering their chromatin vulnerable to fragmentation. This fragmentation process, known as chromothripsis, promotes tumorigenesis by catalysing the activation of oncogenes and the silencing of tumor suppressors. With this role in mind, micronuclei serve as promising targets for therapeutic intervention. This review will explore recent discoveries regarding how micronuclei form, their function in catalysing chromothripsis and how chromothripsis provides a selective advantage for cancer cells.

STING Agonists and How to Reach Their Full Potential in Cancer Immunotherapy

As cancer continues to rank among the leading causes of death, the demand for novel treatments has never been higher. Immunotherapy shows promise, yet many solid tumors such as pancreatic cancer or glioblastoma remain resistant. In these, the "cold" tumor microenvironment with low immune cell infiltration and inactive anti-tumoral immune cells leads to increased tumor resistance to these drugs. This resistance has driven the development of several drug candidates, including stimulators of interferon genes (STING) agonists to reprogram the immune system to fight off tumors. Preclinical studies demonstrated that STING agonists can trigger the cancer immunity cycle and increase type I interferon secretion and T cell activation, which subsequently induces tumor regression. Despite promising preclinical data, biological and physical challenges persist in translating the success of STING agonists into clinical trials. Nonetheless, novel combination strategies are emerging, investigating the combination of these agonists with other immunotherapies, presenting encouraging preclinical results. This review will examine these potential combination strategies for STING agonists and assess the benefits and challenges of employing them in cancer immunotherapy.

Inflammation and tumor immune escape in response to DNA damage

Senescent and cancer cells share common inflammatory characteristics, including factors of the senescence-associated secretory phenotype (SASP) and the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway. Inflammation in the tumor microenvironment not only provides an opportunity for immune cells to attack cancer cells, but also promotes cancer invasion and metastasis. Immune checkpoint molecule PD-L1 is transcriptionally induced by inflammation, and the immunological state of PD-L1-positive tumors influences the efficacy of Immune checkpoint inhibitors (ICIs). ICIs are effective against the PD-L1-positive "hot" tumors; however, the non-immunoactive "cold" tumors that express PD-L1 rarely respond to ICIs, suggesting that converting PD-L1-positive "cold" tumors into "hot" tumors would improve the efficacy of ICIs. To eliminate cancer via the innate immune system, a therapeutic strategy for manipulating inflammatory responses must be established. To date, the molecular mechanisms of inflammation-induced tumorigenesis are not yet fully understood. However, it is becoming clear that the regulatory mechanisms of inflammation in cancer via the cGAS-STING pathway play an important role in both cancer and sensescent cells. In this review, we focus on inflammation and immune escape triggered by DNA damage in cancer and senescent cells.

Nivolumab plus chemotherapy or ipilimumab in gastroesophageal cancer: exploratory biomarker analyses of a randomized phase 3 trial

First-line nivolumab-plus-chemotherapy demonstrated superior overall survival (OS) and progression-free survival versus chemotherapy for advanced gastroesophageal adenocarcinoma with programmed death ligand 1 combined positive score ≥ 5, meeting both primary end points of the randomized phase 3 CheckMate 649 trial. Nivolumab-plus-ipilimumab provided durable responses and higher survival rates versus chemotherapy; however, the prespecified OS significance boundary was not met. To identify biomarkers predictive of differential efficacy outcomes, post hoc exploratory analyses were performed using whole-exome sequencing and RNA sequencing. Nivolumab-based therapies demonstrated improved efficacy versus chemotherapy in hypermutated and, to a lesser degree, Epstein-Barr virus-positive tumors compared with chromosomally unstable and genomically stable tumors. Within the KRAS-altered subgroup, only patients treated with nivolumab-plus-chemotherapy demonstrated improved OS benefit versus chemotherapy. Low stroma gene expression signature scores were associated with OS benefit with nivolumab-based regimens; high regulatory T cell signatures were associated with OS benefit only with nivolumab-plus-ipilimumab. Our analyses suggest that distinct and overlapping pathways contribute to the efficacy of nivolumab-based regimens in gastroesophageal adenocarcinoma.

Functions and mechanisms of eukaryotic RNA-guided programmed DNA elimination

Many eukaryotic organisms, from ciliates to mammals, employ programmed DNA elimination during their postmeiotic reproduction. The process removes specific regions from the somatic DNA and has broad functions, including the irreversible silencing of genes, sex determination, and genome protection from transposable elements or integrating viruses. Multiple mechanisms have evolved that explain the sequence selectivity of the process. In some cases, the eliminated sequences lack centromeres and are flanked by conserved sequence motifs that are specifically recognized and cleaved by designated nucleases. Upon cleavage, all DNA fragments that lack centromeres are lost during the following mitosis. Alternatively, specific sequences can be destined for elimination by complementary small RNAs (sRNAs) as in some ciliates. These sRNAs enable a PIWI-mediated recruitment of chromatin remodelers, followed up by the precise positioning of a cleavage complex formed from a transposase like PiggyBac or Tc1. Here, we review the known molecular interplay of the cellular machinery that is involved in precise sRNA-guided DNA excision, and additionally, we highlight prominent knowledge gaps. We focus on the modes through which sRNAs enable the precise localization of the cleavage complex, and how the nuclease activity is controlled to prevent off-target cleavage. A mechanistic understanding of this process could enable the development of novel eukaryotic genome editing tools.

Cell-Autonomous Immunity: From Cytosolic Sensing to Self-Defense

As an evolutionarily conserved and ubiquitous mechanism of host defense, non-immune cells in vertebrates possess the intrinsic ability to autonomously detect and combat intracellular pathogens. This process, termed cell-autonomous immunity, is distinct from classical innate immunity. In this review, we comprehensively examine the defense mechanisms employed by non-immune cells in response to intracellular pathogen invasion. We provide a detailed analysis of the cytosolic sensors that recognize aberrant nucleic acids, lipopolysaccharide (LPS), and other pathogen-associated molecular patterns (PAMPs). Specifically, we elucidate the molecular mechanisms underlying key signaling pathways, including the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway, the retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs)-mitochondrial antiviral signaling (MAVS) axis, and the guanylate-binding proteins (GBPs)-mediated pathway. Furthermore, we critically evaluate the involvement of these pathways in the pathogenesis of various diseases, including autoimmune disorders, inflammatory conditions, and malignancies, while highlighting their potential as therapeutic targets.

Cancer-derived exosomal circTMEM56 enhances the efficacy of HCC radiotherapy through the miR-136-5p/STING axis

OBJECTIVE

Although the role of circular RNAs (circRNAs) in tumor progression and immune regulation is well-known, the specific circRNA molecules that mediate immune responses after radiotherapy (RT) and the underlying mechanisms have not been identified.

METHODS

Cytometry with time-of-flight (CyTOF) was used to analyze blood samples from patients with liver cancer exhibiting abscopal effects (AEs) after stereotactic body radiotherapy (SBRT) to quantify the number of dendritic cells (DCs) and CD8+ T cells and interferon-beta (IFN-β) level. circTMEM56 and IFN-β levels were measured in 76 patients with liver cancer using qPCR and ELISA. Immunohistochemistry validated circTMEM56 and CD141 staining in tissues. The interaction between circTMEM56, miR-136-5p, and STING, as well as the impact on anti-tumor immunity, was verified using circTMEM56-specific probes, dual-luciferase activity assays, proteomics analysis, and western blot analysis.

RESULTS

The role of circTMEM56 in enhancing anti-tumor immunity and response to RT in hepatocellular carcinoma (HCC) was determined. Higher circTMEM56 levels were linked to an improved RT response and better clinical outcomes in patients with HCC. circTMEM56 enhanced cGAS-STING signaling, increased the number of tumor-infiltrating CD8+ T cells, and elevated the serum IFN-β levels. Moreover, circTMEM56 administration significantly boosted the response to RT in tumors with low circTMEM56 expression.

CONCLUSIONS

High circTMEM56 expression in HCC modulates the distant effects of HCC RT by activating the cGAS-STING pathway to reshape the tumor microenvironment. This study provides a new approach to improve RT efficacy for HCC.

Mitochondrial DNA signals driving immune responses: Why, How, Where?

There has been a recent expansion in our understanding of DNA-sensing mechanisms. Mitochondrial dysfunction, oxidative and proteostatic stresses, instability and impaired disposal of nucleoids cause the release of mitochondrial DNA (mtDNA) from the mitochondria in several human diseases, as well as in cell culture and animal models. Mitochondrial DNA mislocalized to the cytosol and/or the extracellular compartments can trigger innate immune and inflammation responses by binding DNA-sensing receptors (DSRs). Here, we define the features that make mtDNA highly immunogenic and the mechanisms of its release from the mitochondria into the cytosol and the extracellular compartments. We describe the major DSRs that bind mtDNA such as cyclic guanosine-monophosphate-adenosine-monophosphate synthase (cGAS), Z-DNA-binding protein 1 (ZBP1), NOD-, LRR-, and PYD- domain-containing protein 3 receptor (NLRP3), absent in melanoma 2 (AIM2) and toll-like receptor 9 (TLR9), and their downstream signaling cascades. We summarize the key findings, novelties, and gaps of mislocalized mtDNA as a driving signal of immune responses in vascular, metabolic, kidney, lung, and neurodegenerative diseases, as well as viral and bacterial infections. Finally, we define common strategies to induce or inhibit mtDNA release and propose challenges to advance the field.

From pathology to therapy: A comprehensive review of ATRX mutation related molecular functions and disorders

ATRX (alpha-thalassemia/mental retardation, X-linked), a chromatin remodeler, is one of the most commonly mutated genes in human cancer. The ATRX protein functions as a histone chaperone, facilitating the proper folding and assembly of histone proteins into nucleosome cores. Investigations into its molecular mechanisms have significantly advanced our understanding of its roles in diseases associated with chromosomal instability and defective DNA repair. In this comprehensive review, we delineate ATRX's critical function in maintaining heterochromatin integrity and genomic stability under physiological conditions. We further explore the pathogenesis of ATRX-deficient tumors and ATRX syndrome, systematically evaluate current therapeutic strategies for these conditions, and propose novel perspectives on potential targeted therapies for ATRX-mutated malignancies. This review provides useful resource for regarding the etiology and treatment of ATRX deficiency-related diseases.

FDX1 promotes elesclomol-induced PANoptosis in diffuse large B-cell lymphoma via activating IRF3/IFN-β signaling

Diffuse large B-cell lymphoma (DLBCL) remains a major clinical challenge and requires the development of new therapeutic approaches. The identification of cuproptosis, a newly defined form of copper-induced cell death, has provided innovative insights for cancer therapy. Here, we report that loss of the mitochondrial matrix reductase FDX1 in DLBCL cells impairs the antitumor effect of elesclomol (ES), which performs its function by transporting excess copper into cells. Overexpressing (OE) FDX1 significantly sensitized DLBCL cells to ES-induced cell death in vitro and enhanced the anticancer activity of ES in vivo. Furthermore, treatment with ES in FDX1-high expression patient-derived xenograft (PDX) showed a significantly greater inhibitory effect than in FDX1-low expression PDX. Mechanistically, FDX1 promotes the induction of IFN-β-dependent PANoptosis by increasing IRF3 phosphorylation in DLBCL cells upon ES treatment. Consistent with this finding, patient cohort analysis revealed that FDX1 expression correlated positively with enhanced IRF3 phosphorylation. Together, our findings are the first to identify the central role of FDX1 in synergizing with ES to activate IFN-β signaling and induce PANoptosis. This study enables us to re-explore the clinical anticancer potential of ES as a novel therapeutic strategy for DLBCL.

Primary cilia prevent activation of the cGAS-STING pathway during mouse decidualization

Primary cilia are antenna-like organelles that sense extracellular signals and function as signaling hubs essential for vertebrate development and homeostasis. Decidualization is crucial for pregnancy establishment and maintenance in both humans and mice. While primary cilia are present in endometrial stromal cells, their role in pregnancy remains unknown. Here, we identify TMEM67, a key component of the ciliary transition zone, as a critical regulator of mouse decidualization. Loss of primary cilia triggers RhoA-MLC2-dependent actomyosin contraction, which transmits mechanical forces to the nuclear lamina, leading to micronuclei formation. Within these micronuclei, double-stranded DNA (dsDNA) can directly bind to cyclic GMP-AMP synthase (cGAS) in situ, initiating downstream signaling. This activation of the cGAS-STING pathway reduces CCL6 production and impairs decidualization. Furthermore, pharmacological inhibition of actin polymerization or RhoA-ROCK signaling alleviates mechanical forces surrounding stromal cells, restores ciliogenesis, maintains nuclear integrity, suppresses the cGAS-STING pathway activation, and ultimately rescues decidualization. Our findings reveal a previously unrecognized mechanism by which primary cilia regulate the actin cytoskeleton to maintain nuclear integrity and prevent DNA leakage. This safeguards against aberrant activation of the cGAS-STING pathway, which would otherwise trigger detrimental immune signaling and impair decidualization.

cGAS-STING signaling in melanoma: regulation and therapeutic targeting

Melanocytes are the source of the skin cancer known as melanoma. It usually affects the viscera, mucous membranes, and skin. Even so, melanoma only makes for 7% of all skin cancer occurrences. By triggering the generation of type I interferons (IFN-I) and inflammatory cytokines upon identifying microbial DNA, the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway promotes anti-microbial innate immunity. A growing body of research indicates that antitumor immunity depends on the cGAS-STING axis being activated. The cGAS-STING-regulated downstream cytokines, particularly IFN-I, act as linkages between adaptive and innate immunity. As a result, an increasing amount of research has concentrated on the synthesis and screening of agonists of the STING pathway. As a result, an increasing amount of research has concentrated on the synthesis and screening of agonists of the STING pathway. The many implications of the cGAS-STING pathway in the pathophysiology and therapy of melanoma are thoroughly examined in this study. Our research highlights the significance of the cGAS-STING pathway in melanoma and identifies it as a key target for boosting immunity against tumors.

The dilemma of nuclear mechanical forces in DNA damage and repair

Genomic stability, encompassing DNA damage and repair mechanisms, plays a pivotal role in the onset of diseases and the aging process. The stability of DNA is intricately linked to the chemical and mechanical forces exerted on chromatin, particularly within lamina-associated domains (LADs). Mechanical stress can induce DNA damage through the deformation and rupture of the nuclear envelope, leading to DNA bending and cleavage. However, DNA can evade such mechanical stress-induced damage by relocating away from the nuclear membrane, a process facilitated by the depletion of H3K9me3-marked heterochromatin and its cleavage from the lamina. When DNA double-stranded breaks occur, they prompt the rapid recruitment of Lamin B1 and the deposition of H3K9me3. Despite these insights, the precise mechanisms underlying DNA damage and repair under mechanical stress remain unclear. In this review, we explore the interplay between mechanical forces and the nuclear envelope in the context of DNA damage, elucidate the molecular pathways through which DNA escapes force-induced damage, and discuss the corresponding repair strategies involving the nuclear cytoskeleton. By summarizing the mechanisms of force-induced DNA damage and repair, we aim to underscore the potential for developing targeted therapeutic strategies to bolster genomic stability and alleviate the impacts of aging and disease.

Inverse Game Theory Characterizes Frequency-Dependent Selection Driven by Karyotypic Diversity in Triple Negative Breast Cancer

Chromosomal instability (CIN), characterized by pervasive copy number alterations (CNAs), significantly contributes to cancer progression and therapeutic resistance. CNAs drive intratumoral genetic heterogeneity, creating distinct subpopulations whose interactions shape tumor evolution through frequency-dependent selection. Here, we introduce, ECO-K (Ecological-Karyotypes), an inverse game theory framework that infers subpopulation interactions from longitudinal single-cell whole genome sequencing data. Applying this approach to serially-passaged, triple-negative breast cancer (TNBC) cell lines and patient-derived xenografts (PDXs), we systematically identified frequency-dependent selection dynamics governed by karyotypic diversity. Notably, in one PDX lineage, we found consistent evidence of karyotypically defined subpopulations acting as interaction hubs, associated specifically with chromosome 1 loss and chromosome 14p gain. Our framework provides testable predictions of intratumoral ecological dynamics, highlighting opportunities to strategically target key subpopulations to disrupt tumor evolution.

The STING Signaling: A Novel Target for Central Nervous System Diseases

The canonical cyclic GMP-AMP (cGAMP) synthase (cGAS)-Stimulator of Interferon Genes (STING) pathway has been widely recognized as a crucial mediator of inflammation in many diseases, including tumors, infections, and tissue damage. STING signaling can also be activated in a cGAS- or cGAMP-independent manner, although the specific mechanisms remain unclear. In-depth studies on the structural and molecular biology of the STING pathway have led to the development of therapeutic strategies involving STING modulators and their targeted delivery. These strategies may effectively penetrate the blood-brain barrier (BBB) and target STING signaling in multiple central nervous system (CNS) diseases in humans. In this review, we outline both canonical and non-canonical pathways of STING activation and describe the general mechanisms and associations between STING activity and CNS diseases. Finally, we discuss the prospects for the targeted delivery and clinical application of STING agonists and inhibitors, highlighting the STING signaling pathway as a novel therapeutic target in CNS diseases.

The cGAS‒STING pathway in cancer immunity: mechanisms, challenges, and therapeutic implications

Innate immunity represents the body's first line of defense, effectively countering the invasion of external pathogens. Recent studies have highlighted the crucial role of innate immunity in antitumor defense, beyond its established function in protecting against external pathogen invasion. Enhancing innate immune signaling has emerged as a pivotal strategy in cancer therapy. The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway is a key innate immune signal that activates the immune response and exerts antitumor effects; this is primarily attributed to the DNA receptor function of cGAS, which recognizes exogenous DNA to activate downstream STING signaling. This, in turn, promotes the activation of downstream targets such as IRF-3(Interferon Regulatory Factor 3) and NF-κB, leading to the secretion of type I interferons and proinflammatory cytokines, thereby increasing cellular immune activity. The activation of the cGAS-STING pathway may thus play a crucial role in enhancing anticancer immunity. In this paper, we reviewed the role of cGAS-STING signaling in anticancer immunity and its molecular mechanisms. Additionally, we briefly discuss the current applications of the cGAS-STING pathway in cancer immunity, summarize recent developments in STING agonists, and address the challenges facing the use of the cGAS-STING pathway in cancer therapy. Finally, we provide insights into the role of the cGAS‒STING pathway in cancer and propose new directions for cancer immunotherapy.

Chromosomal Instability and Clonal Heterogeneity in Breast Cancer: From Mechanisms to Clinical Applications

BACKGROUND

Chromosomal instability (CIN) and clonal heterogeneity (CH) are fundamental hallmarks of breast cancer that drive tumor evolution, disease progression, and therapeutic resistance. Understanding the mechanisms underlying these phenomena is essential for improving cancer diagnosis, prognosis, and treatment strategies.

METHODS

In this review, we provide a comprehensive overview of the biological processes contributing to CIN and CH, highlighting their molecular determinants and clinical relevance.

RESULTS

We discuss the latest advances in detection methods, including single-cell sequencing and other high-resolution techniques, which have enhanced our ability to characterize intratumoral heterogeneity. Additionally, we explore how CIN and CH influence treatment responses, their potential as therapeutic targets, and their role in shaping the tumor immune microenvironment, which has implications for immunotherapy effectiveness.

CONCLUSIONS

By integrating recent findings, this review underscores the impact of CIN and CH on breast cancer progression and their translational implications for precision medicine.

Intratumoral or Subcutaneous MK-2118, a Noncyclic Dinucleotide STING Agonist, with or without Pembrolizumab, for Advanced or Metastatic Solid Tumors or Lymphomas

PURPOSE

We evaluated the noncyclic dinucleotide stimulator of IFN genes agonist MK-2118 ± pembrolizumab in participants with advanced solid tumors or lymphomas.

PATIENTS AND METHODS

This first-in-human study (NCT03249792) enrolled participants with refractory, advanced solid tumors or lymphomas. Participants received intratumoral (IT) MK-2118 100 to 20,000 μg (arm 1), IT MK-2118 900 to 15,000 μg plus intravenous (IV) pembrolizumab 200 mg every 3 weeks (arm 2), or subcutaneous (SC) MK-2118 5,000 to 150,000 μg plus IV pembrolizumab 200 mg every 3 weeks (arm 4); arm 3 (visceral injection of MK-2118) was not pursued. IT dosing used an accelerated titration design and modified toxicity probability interval method; SC dosing (arm 4) was started subsequent to arms 1 and 2. The primary objectives were safety/tolerability. MK-2118 pharmacokinetics was a secondary endpoint; objective responses and biomarkers were exploratory endpoints.

RESULTS

A total of 140 participants were enrolled (arm 1, n = 27; arm 2, n = 57; arm 4, n = 56). Grade 3/4 treatment-related adverse events occurred in 22%, 23%, and 11% of participants, respectively, but no maximum tolerated dose was identified up to MK-2118 20,000, 15,000, and 150,000 μg across the three arms. Dose-dependent increases in MK-2118 systemic exposure were observed following IT and subcutaneous administration. Objective responses were seen in 0%, 6%, and 4% of participants, respectively. IT MK-2118 led to dose-dependent changes in stimulator of interferon genes-based blood RNA expression levels, IFNγ, IFNγ-induced protein 10, and IL6; SC MK-2118 did not generate dose-related immune responses.

CONCLUSIONS

IT MK-2118 ± pembrolizumab and SC MK-2118 plus pembrolizumab had manageable toxicity and limited antitumor activity. IT but not SC administration demonstrated systemic immune effects.

STING activation and overcoming the challenges associated with STING agonists using ADC (antibody-drug conjugate) and other delivery systems

In current immunotherapy cGAS (cyclic GMP-AMP synthase)-STING (stimulator of interferon genes) pathway considered as most focused area after CAR-T cell. Exploitation of host immunity against cancer using STING agonists generates the most interest as a therapeutic target. Classically cGAS activation through cytoplasmic DNA generates 2'3'cGAMP that is naturally identified STING agonist. Activation of STING leads to activation of type-1 interferon response and pro-inflammatory cytokines through TBK/IRF-3, TBK/NF-κB pathways. Pro-inflammatory cytokines attract immune cells to the tumor microenvironment and type-1 interferon exposes tumor antigens to T cells and NK cells, which leads to the activation of cellular immunity against tumor cells and eliminates tumor cells. Initially bacterial-derived c-di-AMP and c-di-GMP were identified as CDNs (Cyclic-dinucleotide) STING agonists. Moreover, chemically modified CDNs and completely synthetic STING agonists have been developed. Even though the breakthrough preclinical development none of the STING agonists were approved the by FDA for cancer therapy. All identified natural CDNs have poor pharmacokinetic properties due to high hydrophilicity and negative charge. Moreover, phosphodiester bonds in CDNs are most vulnerable to enzymatic degradation. Synthetic STING agonists have an off-target effect that generates autoimmunity and cytokine storm. STING agonist needs to improve for pharmacokinetics, efficacy, and safety. In this scenario delivery systems can overcome the challenges associated with STING agonists. Here, we highlight the ways of STING agonisms as direct and indirect, and further, we also discuss the existing STING agonists associated challenges and ongoing efforts for delivery of STING agonists in the tumor microenvironment (TME) via different non-targeted carriers like Nanoparticle, Hydrogel, Micelle, Liposome. We also discussed the most advanced targeted deliveries of ADC (Antibody-drug conjugate) and aptamers-based delivery.

Unleashing the Potential of Metal Ions in cGAS-STING Activation: Advancing Nanomaterial-Based Tumor Immunotherapy

Immunotherapy is a critical modality in cancer treatment with diverse activation pathways. In recent years, the stimulator of interferon genes (STING) signaling pathway has exhibited significant potential in tumor immunotherapy. This pathway exerts notable antitumor effects by activating innate and adaptive immunity and regulating the tumor immune microenvironment. Various metal ions have been identified as effective activators of the STING pathway and, through the design and synthesis of nanodelivery platforms, have been applied in immunotherapy as well as in combination therapies, such as chemotherapy, chemodynamic therapy, photodynamic therapy, and cancer vaccines. Metal nanomaterials showcase unique advantages in immunotherapy; however, there are still aspects that require optimization. This review systematically examines existing metal-based nanomaterials, elaborates on the mechanisms by which different metal ions activate the STING pathway, and discusses their application models in tumor combination therapies. We also provide a comparative analysis of the advantages of metal nanomaterials over other treatment methods. Our exploration highlights the broad application prospects of metal nanomaterials in cancer treatment, offering new insights and directions for the advancement of tumor immunotherapy.

ATM and IRAK1 orchestrate two distinct mechanisms of NF-κB activation in response to DNA damage

DNA damage in cells induces the expression of inflammatory genes. However, the mechanism by which cells initiate an innate immune response in the presence of DNA lesions blocking transcription remains unknown. Here we find that genotoxic stresses lead to an acute activation of the transcription factor NF-κB through two distinct pathways, each triggered by different types of DNA lesions and coordinated by either ataxia-telangiectasia mutated (ATM) or IRAK1 kinases. ATM stimulates NF-κB in cells with DNA double-strand breaks. By contrast, IRAK1-induced NF-κB signaling occurs in neighboring cells through IL-1α secretion from transcriptionally stressed cells caused by DNA lesions blocking RNA polymerases. Subsequently, both pathways stimulate TRAF6 and the IKK complex to promote NF-κB-mediated inflammatory gene expression. These findings provide an alternative mechanism for damaged cells with impaired transcription to initiate an inflammatory response without relying on their own gene expression, a necessary step that injured cells depend on during canonical innate immune responses.

Single-cell and spatial genomic landscape of non-small cell lung cancer brain metastases

Brain metastases frequently develop in patients with non-small cell lung cancer (NSCLC) and are a common cause of cancer-related deaths, yet our understanding of the underlying human biology is limited. Here we performed multimodal single-nucleus RNA and T cell receptor, single-cell spatial and whole-genome sequencing of brain metastases and primary tumors of patients with treatment-naive NSCLC. Chromosomal instability (CIN) is a distinguishing genomic feature of brain metastases compared with primary tumors, which we validated through integrated analysis of molecular profiling and clinical data in 4,869 independent patients, and a new cohort of 12,275 patients with NSCLC. Unbiased analyses revealed transcriptional neural-like programs that strongly enriched in cancer cells from brain metastases, including a recurring, CINhigh cell subpopulation that preexists in primary tumors but strongly enriched in brain metastases, which was also recovered in matched single-cell spatial transcriptomics. Using multiplexed immunofluorescence in an independent cohort of treatment-naive pairs of primary tumors and brain metastases from the same patients with NSCLC, we validated genomic and tumor-microenvironmental findings and identified a cancer cell population characterized by neural features strongly enriched in brain metastases. This comprehensive analysis provides insights into human NSCLC brain metastasis biology and serves as an important resource for additional discovery.

Regulation of the cGAS-STING Pathway

The cGAS-cGAMP-STING pathway is essential for immune defense against pathogens. Upon binding DNA, cGAS synthesizes cGAMP, which activates STING, leading to potent innate immune effector responses. However, lacking specific features to distinguish between self and nonself DNA, cGAS-STING immunity requires precise regulation to prevent aberrant activation. Several safeguard mechanisms acting on different levels have evolved to maintain tolerance to self DNA and ensure immune homeostasis under normal conditions. Disruption of these safeguards can lead to erroneous activation by self DNA, resulting in inflammatory conditions but also favorable antitumor immunity. Insights into structural and cellular checkpoints that control and terminate cGAS-STING signaling are essential for comprehending and manipulating DNA-triggered innate immunity in health and disease.

cGAS and STING in Host Myeloid Cells Are Essential for Effective Cyclophosphamide Treatment of Advanced Breast Cancer

BACKGROUND/OBJECTIVES

Cyclophosphamide (CTX) treatment in vivo kills proliferating tumor cells by DNA crosslinking; however, the suppression of tumor growth by CTX in several murine models requires CD8+ T cells. Given that CTX induces DNA damage and type I interferon (IFN-I), we investigated the role of host cGAS and STING in the anti-tumor effect of CTX in vivo.

METHODS

A metastasized EO771 breast cancer model with chromosomal instability and bone marrow (BM) chimera approach were used in this study.

RESULTS

We found that CTX therapy induces long-term survival of the mice, with this outcome being dependent on CD8+ T cells and cGAS/STING of BM-derived cells. Furthermore, the STING of type 1 conventional dendritic cells (cDC1s) and LysM+ cells and the IFN-I response of non-cDC1 myeloid cells are essential for CTX efficacy. We also found that the cGAS and STING of BM-derived cells positively modulate intratumoral exhausted and stem-cell-like CD8+ T cell populations under CTX treatment, with the latter only being affected by cGAS.

CONCLUSIONS

Our study demonstrates that the CD8+-T-cell-dependent anti-tumor mechanisms of CTX critically involve the cGAS-STING-IFN-I axis, IFN-I response, and STING-independent cGAS function in host myeloid cells. These findings suggest the deployment of CTX in treating advanced solid tumor to bypass the often-failed IFN-I production by tumor cells due to the chronic activation of intrinsic cGAS-STING caused by chromosomal instability.

Extracellular vesicles in cancer progression: mechanisms and significance

Tumor recurrence, metastasis, clinical drug resistance, and immune evasion are critical events in cancer progression, characterized by significant spatiotemporal heterogeneity and plasticity. Intercellular communication between tumor cells and other cells within the tumor microenvironment plays a pivotal role in these processes. Extracellular vesicles (EVs), heterogeneous secretory messengers carrying bioactive molecules, facilitate this cell-to-cell communication, thereby dynamically influencing cancer progression. Deciphering the mechanisms of EV formation and regulatory pathways and identifying key networks and targets in tumor metastasis, drug resistance, and immune response mediated by EVs will provide new insights into the understanding of cancer progression patterns and offer innovative strategies for cancer diagnosis and therapy.

Brain metastases lung adenocarcinoma patients with BRG1 loss have a grim prognosis, featuring unique morphological and methylation characteristics

BRG1 deficiency in patients with lung adenocarcinoma that has metastasized to the brain, termed BRG1-deficient brain metastasis lung adenocarcinoma, is an uncommon event. Prior to this study, these patients had not undergone extensive molecular and (epi)genetic analysis. We report a comprehensive clinical, histopathologic, and molecular assessment of 9 BRG1-deficient brain metastasis lung adenocarcinoma cohort (BRG1-deficient BM cohort) in comparison with a 16 BRG1-retained brain metastasis lung adenocarcinoma cohort (BRG1-retained BM cohort). Patients with BRG1-deficient BM exhibited a significantly increased risk of mortality. Molecular analysis revealed a high prevalence of mutations in SMARCA4 and TP53 genes within this group. DNA methylation molecular diagnostics showed a high rate of genomic instability and a markedly lower DNA methylation age in these patients. Functional enrichment analysis of differentially methylated genes suggested that hypomethylation genes were primarily associated with the negative regulation of neuron differentiation, G protein-coupled receptor signaling pathways, and cell differentiation. Conversely, hypermethylation was linked to the regulation of small GTPase mediated signal transduction, Rho protein signal transduction, DNA damage response, and apoptotic processes. This study investigated a rare subgroup of lung adenocarcinoma patients with brain metastasis characterized by BRG1 deficiency and a poor prognosis. Our study not only provides a comprehensive multi-omic data resource but also provides valuable biological insights into patients. The findings may serve as a valuable reference for the future pathological diagnosis of BRG1-deficient brain metastasis in lung adenocarcinoma patients.

Sp1 mechanotransduction regulates breast cancer cell invasion in response to multiple tumor-mimicking extracellular matrix cues

Breast cancer progression is marked by extracellular matrix (ECM) remodeling, including increased stiffness, faster stress relaxation, and elevated collagen levels. In vitro experiments have revealed a role for each of these factors to individually promote malignant behavior, but their combined effects remain unclear. To address this, we developed alginate-collagen hydrogels with independently tunable stiffness, stress relaxation, and collagen density. We show that these combined tumor-mimicking ECM cues reinforced invasive morphologies and promoted spheroid invasion in breast cancer and mammary epithelial cells. High stiffness and low collagen density in slow-relaxing matrices led to the greatest cell migration speed and displacement. RNA-seq revealed Sp1 target gene enrichment in response to both individual and combined ECM cues, with a greater enrichment observed under multiple cues. Notably, high expression of Sp1 target genes upregulated by fast stress relaxation correlated with poor patient survival. Mechanistically, we found that phosphorylated-Sp1 (T453) was increasingly located in the nucleus in stiff and/or fast relaxing matrices, which was regulated by PI3K and ERK1/2 signaling, as well as actomyosin contractility. This study emphasizes how multiple ECM cues in complex microenvironments reinforce malignant traits and supports an emerging role for Sp1 as a mechanoresponsive transcription factor.

Cytosolic nucleic acid sensing as driver of critical illness: mechanisms and advances in therapy

Nucleic acids from both self- and non-self-sources act as vital danger signals that trigger immune responses. Critical illnesses such as acute respiratory distress syndrome, sepsis, trauma and ischemia lead to the aberrant cytosolic accumulation and massive release of nucleic acids that are detected by antiviral innate immune receptors in the endosome or cytosol. Activation of receptors for deoxyribonucleic acids and ribonucleic acids triggers inflammation, a major contributor to morbidity and mortality in critically ill patients. In the past decade, there has been growing recognition of the therapeutic potential of targeting nucleic acid sensing in critical care. This review summarizes current knowledge of nucleic acid sensing in acute respiratory distress syndrome, sepsis, trauma and ischemia. Given the extensive research on nucleic acid sensing in common pathological conditions like cancer, autoimmune disorders, metabolic disorders and aging, we provide a comprehensive summary of nucleic acid sensing beyond critical illness to offer insights that may inform its role in critical conditions. Additionally, we discuss potential therapeutic strategies that specifically target nucleic acid sensing. By examining nucleic acid sources, sensor activation and function, as well as the impact of regulating these pathways across various acute diseases, we highlight the driving role of nucleic acid sensing in critical illness.

Chromosomal Instability Is Associated with cGAS-STING Activation in EGFR-TKI Refractory Non-Small-Cell Lung Cancer

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are standard therapies for EGFR-mutated non-small-cell lung cancer (NSCLC); however, their efficacy is inconsistent. Secondary mutations in the EGFR or other genes that lead to resistance have been identified, but resistance mechanisms have not been fully identified. Chromosomal instability (CIN) is a hallmark of cancer and results in genetic diversity. In this study, we demonstrated by transcriptomic analysis that CIN activates the cGAS-STING signaling pathway, which leads to EGFR-TKI refractoriness in a subset of EGFR-mutated NSCLC patients. Furthermore, EGFR-mutated H1975dnMCAK cells, which frequently underwent chromosomal mis-segregation, demonstrated refractoriness to the EGFR-TKI osimertinib compared to control cells. Second, H1975dnMCAK cells exhibited activation of cGAS-STING signaling and its downstream signaling, including tumor-promoting cytokine IL-6. Finally, chromosomally unstable EGFR-mutated NSCLC exhibited enhanced epithelial-mesenchymal transition (EMT). Blockade of cGAS-STING-TBK1 signaling reversed EMT, resulting in restored susceptibility to EGFR-TKIs in vitro and in vivo. These results suggest that CIN may lead to the activation of cGAS-STING signaling in some EGFR-mutated NSCLC, resulting in EMT-associated EGFR-TKI resistance.

Targeting cGAS-STING pathway for reprogramming tumor-associated macrophages to enhance anti-tumor immunotherapy

The cyclic GMP-AMP synthase (cGAS)-stimulator interferon genes (STING) signaling pathway plays a crucial role in activating innate and specific immunity in anti-tumor immunotherapy. As the major infiltrating cells in the tumor microenvironment (TME), tumor-associated macrophages (TAMs) could be polarized into either anti-tumor M1 or pro-tumor M2 types based on various stimuli. Accordingly, targeted reprogramming TAMs to restore immune balance shows promise as an effective anti-tumor strategy. In this review, we aim to target cGAS-STING pathway for reprogramming TAMs to enhance anti-tumor immunotherapy. We investigated the double-edged sword effects of cGAS-STING in regulating TME. The regulative roles of cGAS-STING pathway in TAMs and its impact on the TME were further revealed. More importantly, several strategies of targeting cGAS-STING for reprogramming TAMs were designed for enhancing anti-tumor immunotherapy. Taken together, targeting cGAS-STING pathway for reprogramming TAMs in TME might be a promising strategy to enhance anti-tumor immunotherapy.

Potential for micronuclear turnover through autophagy secretion pathway

Micronuclei (MN) serve as well-established markers of genomic instability. MN arise from various stresses, such as segregation errors and mechanical stress, and are subsequently eliminated by the autophagy pathway. It has been suggested that MN are traditionally considered markers of cancer cells, often without recognized functional significance. Meanwhile, we recently discovered that MN act as mediators in regulating microglial characteristics. Neurons produce MN in response to migrating stress during the developmental stage and release them to the extracellular space, subsequently transferring them to microglia. In this study, we report the potential mechanisms underlying MN release through the autophagic secretion pathway. Our data show a possibility by which damaged MN are recognized autophagy regulatory factors, resulting in the propagation of MN to microglia.

Computational Cellular Mathematical Model Aids Understanding the cGAS-STING in NSCLC Pathogenicity

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer. According to 2020 reports, globally, 2.2 million cases are reported every year, with the mortality number being as high as 1.8 million patients. To study NSCLC, systems biology offers mathematical modeling as a tool to understand complex pathways and provide insights into the identification of biomarkers and potential therapeutic targets, which aids precision therapy. Mathematical modeling, specifically ordinary differential equations (ODEs), is used to better understand the dynamics of cancer growth and immunological interactions in the tumor microenvironment. This study highlighted the dual role of the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS/STING) pathway's classical involvement in regulating type 1 interferon (IFN I) and pro-inflammatory responses to promote tumor regression through senescence and apoptosis. Alternative signaling was induced by nuclear factor kappa B (NF-κB), mutated tumor protein p53 (p53), and programmed death-ligand1 (PD-L1), which lead to tumor growth. We identified key regulators in cancer progression by simulating the model and validating it with the following model estimation parameters: local sensitivity analysis, principal component analysis, rate of flow of metabolites, and model reduction. Integration of multiple signaling axes revealed that cGAS-STING, phosphoinositide 3-kinases (PI3K), and Ak strain transforming (AKT) may be potential targets that can be validated for cancer therapy. Key features • Procedures for the reconstruction of a robust and steady-state mathematical model with respective analysis in order to provide mechanistic insights. • The dynamic mathematical model allows an understanding of the multifaceted dual roles of cGAS-STING in NSCLC promotion and inhibition. • The inherent statistical tool in systems biology provides a novel immunotherapeutic target.

micronuclAI enables automated quantification of micronuclei for assessment of chromosomal instability

Chromosomal instability (CIN) is a hallmark of cancer that drives metastasis, immune evasion and treatment resistance. CIN may result from chromosome mis-segregation errors and excessive chromatin is frequently packaged in micronuclei (MN), which can be enumerated to quantify CIN. The assessment of CIN remains a predominantly manual and time-consuming task. Here, we present micronuclAI, a pipeline for automated and reliable quantification of MN of varying size and morphology in cells stained only for DNA. micronuclAI can achieve close to human-level performance on various human and murine cancer cell line datasets. The pipeline achieved a Pearson's correlation of 0.9278 on images obtained at 10X magnification. We tested the approach in otherwise isogenic cell lines in which we genetically dialed up or down CIN rates, and on several publicly available image datasets where we achieved a Pearson's correlation of 0.9620. Given the increasing interest in developing therapies for CIN-driven cancers, this method provides an important, scalable, and rapid approach to quantifying CIN on images that are routinely obtained for research purposes. We release a GUI-implementation for easy access and utilization of the pipeline.

TAX1BP1-dependent autophagic degradation of STING1 impairs anti-tumor immunity

The activation of STING1 can lead to the production and secretion of cytokines, initiating antitumor immunity. Here, we screened an ion channel ligand library and identified tetrandrine, a bis-benzylisoquinoline alkaloid, as an immunological adjuvant that enhances antitumor immunity by preventing the autophagic degradation of the STING1 protein. This tetrandrine effect is independent of its known function as a calcium or potassium channel blocker. Instead, tetrandrine inhibits lysosomal function, impairing cathepsin maturation, and autophagic degradation. Proteomic analysis of lysosomes identified TAX1BP1 as a novel autophagic receptor for the proteolysis of STING1. TAX1BP1 recognizes STING1 through the physical interaction of its coiled-coil domain with the cyclic dinucleotide binding domain of STING1. Systematic mutation of lysine (K) residues revealed that K63-ubiquitination of STING1 at the K224 site ignites TAX1BP1-dependent STING1 degradation. Combined treatment with tetrandrine and STING1 agonists promotes antitumor immunity by converting "cold" pancreatic cancers into "hot" tumors. This process is associated with enhanced cytokine release and increased infiltration of cytotoxic T-cells into the tumor microenvironment. The antitumor immunity mediated by tetrandrine and STING1 agonists is limited by neutralizing antibodies to the type I interferon receptor or CD8+ T cells. Thus, these findings establish a potential immunotherapeutic strategy against pancreatic cancer by preventing the autophagic degradation of STING1.

STING in cancer immunoediting: Modeling tumor-immune dynamics throughout cancer development

Cancer immunoediting is a dynamic process of tumor-immune system interaction that plays a critical role in cancer development and progression. Recent studies have highlighted the importance of innate signaling pathways possessed by both cancer cells and immune cells in this process. The STING molecule, a pivotal innate immune signaling molecule, mediates DNA-triggered immune responses in both cancer cells and immune cells, modulating the anti-tumor immune response and shaping the efficacy of immunotherapy. Emerging evidence has shown that the activation of STING signaling has dual opposing effects in cancer progression, simultaneously provoking and restricting anti-tumor immunity, and participating in every phase of cancer immunoediting, including immune elimination, equilibrium, and escape. In this review, we elucidate the roles of STING in the process of cancer immunoediting and discuss the dichotomous effects of STING agonists in the cancer immunotherapy response or resistance. A profound understanding of the sophisticated roles of STING signaling pathway in cancer immunoediting would potentially inspire the development of novel cancer therapeutic approaches and overcome the undesirable protumor effects of STING activation.