Trending Topics in Gastroenterology | GastroAGI

Inflammation Creates New Therapeutic Vulnerabilities in Cancer: Nature Genetics | June 2026

• Cancer cells constantly adapt to inflammatory stress generated by the immune system, particularly during immune checkpoint inhibitor therapy. • This study explored whether inflammatory cytokines such as interferon-γ (IFNγ), interferon-β, and TNF create new weaknesses that can be therapeutically exploited. • Using genome-wide CRISPR screening across multiple cancer models, investigators identified previously unrecognized cancer dependencies that emerge specifically under inflammatory conditions. • Two major targets emerged: GPI transamidase complex FITM2 (Fat Storage-Inducing Transmembrane Protein 2) • These genes were not simply general survival genes; they became particularly important when tumour cells were exposed to interferon signaling. • Deletion of GPI transamidase components or FITM2 significantly enhanced tumour responses to immune checkpoint blockade in preclinical models. • Mechanistic studies revealed that FITM2 loss makes tumour cells highly susceptible to interferon-driven stress responses. • Inflammatory cytokines triggered excessive endoplasmic reticulum stress and oxidative stress in FITM2-deficient cancer cells. • This ultimately resulted in a distinctive form of programmed cell death resembling paraptosis, which differs from classical apoptosis. • The findings suggest that immune activation does not only attack cancer directly but may also expose previously hidden metabolic and stress-related vulnerabilities. • This represents an important conceptual advance in immuno-oncology: inflammatory signaling may create new drug targets that only become relevant during active antitumour immune responses. • Combining immune checkpoint inhibitors with therapies targeting inflammation-induced dependencies could potentially improve response rates and overcome resistance. • The study also highlights the growing role of functional genomics and CRISPR screening in identifying context-specific cancer vulnerabilities. • Although the work remains preclinical, it provides a framework for developing combination strategies that exploit tumour adaptation to immune pressure. • Future therapeutic development may focus on pharmacologic inhibition of FITM2-related pathways or GPI transamidase function alongside immunotherapy. Bottom line: Antitumour inflammatory cytokines do more than activate immune responses—they create new tumour-specific dependencies. Targeting FITM2 and GPI transamidase–related pathways may enhance the effectiveness of immune checkpoint blockade and open a new avenue for precision immuno-oncology.

F. nucleatum Linked to Worse CRC Survival : Cancer | June 2026

Introduction: The colorectal cancer (CRC) microbiome has emerged as a key factor influencing tumor development, progression, and response to treatment. Among microbial species implicated in CRC, Fusobacterium nucleatum (F. nucleatum), an oral anaerobic bacterium, has received considerable attention due to its association with tumorigenesis, immune modulation, and aggressive disease behavior. However, the relationship between intratumoral F. nucleatum and CRC-specific mortality across diverse patient populations remains incompletely understood. Problem Statement: Although previous studies have linked F. nucleatum to colorectal carcinogenesis, its impact on long-term survival and whether this association differs according to tumor location or age at diagnosis have not been clearly established. Identifying high-risk patient subgroups associated with microbial signatures could improve prognostication and guide future microbiome-targeted interventions. Summary: This study evaluated the association between intratumoral F. nucleatum and CRC-specific mortality in a large, heterogeneous United States population. The investigators found that the presence of F. nucleatum within tumor tissue was associated with significantly poorer CRC-specific survival, supporting its role as a clinically relevant prognostic biomarker. Importantly, the adverse association was not uniform across all patients. The impact of F. nucleatum was particularly pronounced in rectal cancer, where its presence was strongly linked to increased mortality, while the association was considerably weaker in colon cancers. Similarly, the relationship was substantially stronger in patients with early-onset CRC than in those diagnosed at older ages, suggesting that microbial influences may contribute differently across distinct biological subtypes of the disease. These findings reinforce the growing concept that CRC is shaped not only by tumor genetics but also by interactions with the tumor-associated microbiome. The study highlights F. nucleatum as a potential marker of aggressive disease and supports ongoing efforts to incorporate microbial profiling into CRC risk stratification. Future research should explore whether targeting F. nucleatum through microbiome-directed therapies can improve outcomes, particularly in patients with rectal cancer and early-onset CRC.

Inflammation Creates New Therapeutic Vulnerabilities in Cancer: Nature Genetics | June 2026

* Cancer cells constantly adapt to inflammatory stress generated by the immune system, particularly during immune checkpoint inhibitor therapy. * This study explored whether inflammatory cytokines such as interferon-γ (IFNγ), interferon-β, and TNF create new weaknesses that can be therapeutically exploited. * Using genome-wide CRISPR screening across multiple cancer models, investigators identified previously unrecognized cancer dependencies that emerge specifically under inflammatory conditions. * Two major targets emerged: * GPI transamidase complex * FITM2 (Fat Storage-Inducing Transmembrane Protein 2) * These genes were not simply general survival genes; they became particularly important when tumour cells were exposed to interferon signaling. * Deletion of GPI transamidase components or FITM2 significantly enhanced tumour responses to immune checkpoint blockade in preclinical models. * Mechanistic studies revealed that FITM2 loss makes tumour cells highly susceptible to interferon-driven stress responses. * Inflammatory cytokines triggered excessive endoplasmic reticulum stress and oxidative stress in FITM2-deficient cancer cells. * This ultimately resulted in a distinctive form of programmed cell death resembling paraptosis, which differs from classical apoptosis. * The findings suggest that immune activation does not only attack cancer directly but may also expose previously hidden metabolic and stress-related vulnerabilities. * This represents an important conceptual advance in immuno-oncology: inflammatory signaling may create new drug targets that only become relevant during active antitumour immune responses. * Combining immune checkpoint inhibitors with therapies targeting inflammation-induced dependencies could potentially improve response rates and overcome resistance. * The study also highlights the growing role of functional genomics and CRISPR screening in identifying context-specific cancer vulnerabilities. * Although the work remains preclinical, it provides a framework for developing combination strategies that exploit tumour adaptation to immune pressure. * Future therapeutic development may focus on pharmacologic inhibition of FITM2-related pathways or GPI transamidase function alongside immunotherapy. Bottom line: Antitumour inflammatory cytokines do more than activate immune responses—they create new tumour-specific dependencies. Targeting FITM2 and GPI transamidase–related pathways may enhance the effectiveness of immune checkpoint blockade and open a new avenue for precision immuno-oncology.

TLS Atlas: Turning Tumor Immune Architecture into a Clinical Biomarker: Science | May 2026

* Tertiary lymphoid structures are local immune hubs within tumors, but this study shows that their mere presence is not enough; their maturation, location, and cellular organization determine biological and clinical relevance. * This pan-cancer study analyzed TLS biology across 12 cancer types, combining spatial transcriptomics with artificial intelligence applied to routine H&E pathology slides. * TLSs were classified along a maturation spectrum: early TLS, primary follicle–like TLS, and secondary follicle–like TLS, reflecting increasing immune organization. * Mature TLSs showed coordinated immune architecture, including B-cell and T-cell zoning, follicular dendritic cell networks, chemokine signaling, and interferon-related immune activation. * The spatial position of TLSs mattered. Intratumoral, peritumoral, and distal TLSs were associated with different immune and tumor signaling patterns. * Tumor regions close to intratumoral TLSs showed stronger antigen presentation and immune activation signatures, including interferon and MHC class II pathways. * Tumor regions farther from TLSs showed relatively higher proliferative and invasive programs, including MYC signaling, cell-cycle activity, and epithelial–mesenchymal transition. * The authors developed an AI-based model capable of detecting and phenotyping TLSs directly from standard H&E whole-slide images, making the approach potentially scalable for routine pathology. * A maturation-aware TLS composite score performed better than simple “TLS present or absent” assessment for patient stratification across cancer and treatment settings. * This work suggests that TLS profiling may become a future immuno-oncology biomarker, helping predict prognosis, treatment response, and possibly guide trial design. * The clinical implication is important: future cancer immunotherapy decisions may depend not only on tumor genomics or PD-L1 expression, but also on the spatial immune architecture of the tumor microenvironment. * Prospective validation is still needed before TLS scoring can be used routinely in clinical practice. Bottom line: This study transforms TLSs from a descriptive pathology feature into a measurable, AI-enabled spatial biomarker with potential relevance for immunotherapy selection and cancer prognosis.

CLDN18.2 in PDAC: KRAS and Hyperglycaemia Create a Resistance Mechanism: Gut | 2026

* CLDN18.2 is emerging as a therapeutic target in gastrointestinal cancers, but its benefit in pancreatic ductal adenocarcinoma has been limited. * This study identifies a key resistance mechanism: KRAS mutation and hyperglycaemia drive O-GlcNAcylation of CLDN18.2, a sugar-based post-translational modification. * The modification occurs at the T204 site of CLDN18.2 and changes its cellular behaviour. * Instead of remaining on the tumour cell membrane where CLDN18.2-targeted therapies can bind effectively, O-GlcNAcylated CLDN18.2 accumulates in the cytoplasm. * This loss of membrane localization may explain why some pancreatic cancers expressing CLDN18.2 still respond poorly to CLDN18.2-targeted therapy. * O-GlcNAcylated CLDN18.2 is not just a passive resistance marker; it actively promotes pancreatic cancer migration, invasion, and metastasis. * Mechanistically, O-GlcNAcylated CLDN18.2 shows reduced binding to PTP1B, leading to increased tyrosine phosphorylation. * This allows CLDN18.2 to recruit Src through its SH2 domain, activating Src signaling and enhancing aggressive tumour biology. * Genetic blockade of the O-GlcNAcylation site, using the T204A mutation, restored CLDN18.2 membrane localization and reduced tumour progression in experimental models. * Pharmacological inhibition of O-GlcNAcylation produced similar benefits, suggesting that this pathway is therapeutically targetable. * Low-dose MRTX1133, a KRASG12D inhibitor, reduced CLDN18.2 O-GlcNAcylation and restored membrane localization in KRAS-mutant PDAC models. * Combining low-dose MRTX1133 with CLDN18.2-targeted therapy improved antitumour efficacy with minimal side effects in preclinical models. * The study suggests that CLDN18.2 testing should not focus only on expression level; subcellular localization may be equally important. * Hyperglycaemia may be clinically relevant because metabolic status could influence CLDN18.2 modification, localization, and therapeutic response. * This is an important translational study, but the proposed strategy still requires clinical validation before routine use. Bottom line: KRAS mutation and hyperglycaemia can convert CLDN18.2 from a membrane-accessible therapeutic target into a cytoplasmic, pro-metastatic, therapy-resistant protein. Targeting KRAS-driven O-GlcNAcylation may restore CLDN18.2-targeted therapy sensitivity in pancreatic cancer.

The Oral–X Axis: How Oral Dysbiosis Drives Systemic Disease: Genes & Diseases | June 2026

* The oral cavity contains the second largest microbial ecosystem in the human body and acts as a major interface between the external environment and multiple organ systems. * This review introduces the concept of the “Oral–X Axis,” describing the bidirectional relationship between oral microbiota and distant organs including the gut, liver, cardiovascular system, lungs, kidneys, and brain. * Oral dysbiosis is not merely a dental problem; it may contribute to the development and progression of multiple chronic systemic diseases. * Oral microbes and their metabolites can reach distant organs through bloodstream dissemination, swallowing into the gastrointestinal tract, and respiratory micro-aspiration. * Key microbial products implicated in systemic disease include lipopolysaccharides (LPS), short-chain fatty acids (SCFAs), bile acid metabolites, and other inflammatory mediators. * These microbial signals influence immune regulation, inflammatory pathways, endothelial function, metabolic homeostasis, and tissue injury in distant organs. * The oral–gut axis is particularly important. Oral pathogens can alter intestinal microbial composition, increase gut permeability, and amplify systemic inflammation. * The oral–liver axis contributes to progression of MASLD, steatohepatitis, cirrhosis, and potentially hepatocellular carcinoma through inflammatory and metabolic mechanisms. * The oral–cardiovascular axis links periodontal disease and oral dysbiosis with atherosclerosis, endothelial dysfunction, thrombosis, and cardiovascular events. * The oral–brain axis is increasingly implicated in neuroinflammation, cognitive decline, neurodegenerative diseases, and cerebrovascular disorders. * The oral–lung axis may contribute to respiratory infections, chronic pulmonary inflammation, and adverse outcomes in chronic lung diseases. * The oral–kidney axis suggests reciprocal interactions between chronic kidney disease and oral microbial imbalance through inflammatory and metabolic pathways. * Importantly, these relationships are bidirectional. Disease in distant organs can also alter the oral microenvironment, further worsening oral dysbiosis and creating a self-perpetuating cycle. * Advances in sequencing technologies, metabolomics, and microbiome research are providing new insights into these complex host–microbe interactions. * Potential future therapeutic approaches include periodontal treatment, microbiome modulation, probiotics, targeted antimicrobial strategies, dietary interventions, and personalized microbiome-based medicine. * The review strongly argues that oral health should become an integral component of chronic disease management rather than being viewed as a separate specialty concern. Bottom line: The oral cavity functions as a systemic microbial gateway. Oral dysbiosis influences inflammation, immunity, and metabolism across multiple organs, making oral health an important but often underrecognized determinant of chronic disease outcomes.

Exercise After Bariatric Surgery: Gut Microbiota as a Metabolic Amplifier: International Journal of Obesity | June 2026

* This translational study investigated whether exercise-induced changes in gut microbiota contribute to the metabolic benefits observed after Roux-en-Y gastric bypass surgery. * Thirty-two women undergoing bariatric surgery were randomized to surgery alone or surgery plus a structured 6-month exercise program beginning three months after surgery. * Both groups achieved similar reductions in body weight, fat mass, and systemic inflammation, indicating that the additional benefits of exercise were not explained by greater weight loss. * Patients who exercised experienced superior metabolic improvements, including better HDL cholesterol levels, lower triglycerides, lower fasting glucose, and lower fasting insulin concentrations. * Exercise was associated with increased gut microbiota diversity, a feature generally linked to improved metabolic health. * The exercise group showed enrichment of bacterial genera associated with short-chain fatty acid production and favorable host metabolic regulation. * To investigate causality, researchers transplanted stool samples from post-surgery patients into high-fat diet-fed mice. * Mice receiving microbiota from exercised bariatric patients demonstrated lower fasting insulin levels and reduced insulin resistance compared with mice receiving microbiota from surgery-only patients. * These findings suggest that exercise modifies the gut microbiome in ways that contribute directly to improved insulin sensitivity. * Interestingly, glucose tolerance and systemic inflammation were similar between groups, indicating that microbiota-mediated effects may be especially important for insulin regulation rather than all metabolic outcomes. * Exercise-conditioned microbiota also partially preserved intestinal structure, suggesting potential benefits on gut integrity and host-microbe interactions. * The study strengthens the concept that exercise acts not only through muscle and energy expenditure but also through microbiome remodeling. * Clinically, the findings support exercise as an essential component of post-bariatric care, even when additional weight loss is minimal. * The study also raises the possibility that future microbiome-based therapies could mimic some of the metabolic benefits of exercise after bariatric surgery. * Limitations include a relatively small human cohort and inclusion of only female patients, requiring validation in larger and more diverse populations. Bottom line: Exercise after Roux-en-Y gastric bypass appears to reprogram the gut microbiota, generating microbial communities that improve insulin sensitivity and metabolic health beyond the effects of surgery and weight loss alone.

Bacterial Signaling Molecules Drive Colitis-Associated Cancer : Gastroenterology | Jun 2026

Introduction: Chronic inflammation is the principal driver of colitis-associated cancer (CAC) in patients with long-standing ulcerative colitis (UC). Although the intestinal microbiome has long been implicated in colorectal carcinogenesis, the precise microbial mediators linking inflammation to tumor development remain incompletely understood. Quorum-sensing molecules (QSMs), bacterial communication signals that regulate microbial behavior, have emerged as potential mediators of host–microbiome interactions, but their role in CAC has not previously been defined. Problem Statement: Current risk stratification for CAC relies largely on clinical factors such as disease duration and inflammatory burden, while mechanistic biomarkers directly linking microbial activity to carcinogenesis remain lacking. Determining whether bacterial signaling molecules actively promote tumorigenesis could reveal novel biomarkers and therapeutic targets for cancer prevention in UC. Summary: This translational study investigated the role of bacterial quorum-sensing molecules in UC-associated carcinogenesis using patient samples, murine CAC models, germ-free animals, microbiome analyses, metabolomics, and organoid systems. Investigators measured three major classes of bacterial QSMs in blood samples from patients with UC and found significantly elevated levels of short-chain N-acyl homoserine lactones (scAHLs) compared with healthy controls. Importantly, patients with active inflammation and disease duration exceeding 10 years—two major risk factors for CAC—demonstrated particularly high levels of the bacterial signaling molecule autoinducer-2. Among the identified QSMs, C6-short-chain acyl homoserine lactone (C6-scAHL) emerged as a key candidate mediator. Administration of C6-scAHL to murine models of CAC significantly increased both tumor number and tumor size, demonstrating a direct pro-tumorigenic effect. Notably, tumor promotion persisted even in germ-free mice, indicating that C6-scAHL can drive carcinogenesis independently of the broader microbiome. This finding suggests that bacterial communication molecules themselves function as biologically active mediators rather than merely markers of microbial dysbiosis. Exposure to C6-scAHL also induced microbiome and metabolomic alterations resembling those observed during chronic intestinal inflammation, further linking bacterial signaling pathways with tumor-promoting microenvironments. Mechanistic studies using murine and human colonic organoids demonstrated that C6-scAHL directly stimulated the production of proinflammatory and protumorigenic cytokines. These cytokine responses provide a plausible biological pathway through which bacterial signaling molecules enhance chronic inflammation and facilitate malignant transformation. The study therefore identifies a previously unrecognized microbiome–host communication pathway contributing to CAC development. Rather than acting through bacterial colonization alone, microbial communities may influence carcinogenesis through diffusible signaling molecules capable of modulating host immune and epithelial responses. Clinically, these findings are important because they identify circulating QSMs as potential biomarkers for CAC risk assessment. Elevated C6-scAHL and autoinducer-2 levels may help identify UC patients at greatest risk of malignant progression, particularly those with long-standing inflammatory disease. Furthermore, targeting bacterial quorum-sensing pathways represents an entirely new preventive strategy for CAC. Therapeutic interventions aimed at blocking QSM production, neutralizing signaling molecules, or interrupting downstream host responses could potentially reduce cancer risk without broadly disrupting the intestinal microbiome. Overall, this study establishes bacterial quorum-sensing molecules, particularly C6-scAHL, as active drivers of colitis-associated carcinogenesis and reveals a novel microbiome-derived signaling axis that may serve as both a biomarker and therapeutic target for cancer prevention in ulcerative colitis.

KRAS–O-GlcNAc Axis Drives CLDN18.2 Resistance in PDAC : Gut | June 2026

Introduction: Introduction: Claudin 18.2 (CLDN18.2) has emerged as an important therapeutic target in gastrointestinal malignancies, with encouraging results in gastric and gastroesophageal cancers. Its expression in pancreatic ductal adenocarcinoma (PDAC) has generated considerable interest for targeted therapies. However, clinical responses in PDAC have been less impressive than anticipated, suggesting that tumor-specific biological mechanisms may limit treatment efficacy. Problem Statement: Problem Statement: The reasons underlying the modest activity of CLDN18.2-targeted therapies in PDAC remain poorly understood. Given the near-universal prevalence of KRAS mutations and the frequent coexistence of metabolic dysfunction and hyperglycemia in pancreatic cancer, identifying mechanisms that alter CLDN18.2 localization and therapeutic accessibility is critical for improving treatment outcomes. Summary: Summary: This comprehensive translational study investigated the impact of O-linked N-acetylglucosaminylation (O-GlcNAcylation) on CLDN18.2 biology using patient samples, patient-derived organoids, patient-derived xenografts, orthotopic models, and genetically engineered mouse models. The investigators identified a previously unrecognized mechanism whereby KRAS mutations and hyperglycemia cooperate to induce O-GlcNAcylation of CLDN18.2 at the T204 residue. This post-translational modification altered CLDN18.2 subcellular trafficking, causing accumulation within the cytoplasm rather than on the cell membrane. Because CLDN18.2-targeted therapies require membrane surface expression for effective target engagement, cytoplasmic sequestration substantially reduced therapeutic susceptibility. Beyond therapeutic resistance, O-GlcNAcylated CLDN18.2 actively promoted tumor aggressiveness. Increased O-GlcNAcylation enhanced cancer cell migration, invasion, and metastatic potential, indicating that this modification is not merely a biomarker of resistance but a functional driver of disease progression. Mechanistically, O-GlcNAcylation disrupted CLDN18.2 interaction with PTP1B, resulting in enhanced tyrosine phosphorylation. This facilitated recruitment and activation of Src kinase through SH2-domain interactions, triggering downstream oncogenic signaling pathways associated with invasion and metastasis. Importantly, both genetic inhibition and pharmacologic suppression of O-GlcNAcylation restored CLDN18.2 membrane localization and attenuated tumor progression. A particularly important therapeutic finding was the effect of low-dose MRTX1133, a KRASG12D inhibitor. Treatment reduced CLDN18.2 O-GlcNAcylation, restored membrane expression, and significantly enhanced the efficacy of CLDN18.2-targeted therapy in KRAS-mutant PDAC models while maintaining a favorable toxicity profile. The study establishes a direct mechanistic link between oncogenic KRAS signaling, metabolic dysregulation, glycosylation biology, and therapeutic resistance. It also provides a biological explanation for why CLDN18.2-directed approaches have underperformed in pancreatic cancer despite target expression. From a clinical perspective, these findings have several implications. Hyperglycemia may influence responsiveness to CLDN18.2-targeted therapies, suggesting a potential role for metabolic optimization in treatment strategies. Assessment of CLDN18.2 membrane localization, rather than total expression alone, may become important when selecting patients for targeted therapy. Furthermore, combining KRAS inhibition with CLDN18.2-directed agents may represent a rational precision oncology approach for KRAS-mutant PDAC. This work is particularly significant because it converts a major resistance mechanism into a therapeutic opportunity. Rather than abandoning CLDN18.2 as a target in PDAC, the study demonstrates that modifying its cellular localization can restore drug sensitivity. Overall, the study identifies KRAS-driven O-GlcNAcylation of CLDN18.2 as a central mechanism linking tumor progression and therapeutic resistance in pancreatic cancer and provides a strong preclinical rationale for combining KRASG12D inhibition with CLDN18.2-targeted therapies to improve outcomes in this highly lethal disease.

APE1–SOX9 Axis Drives Chemoresistance in Esophageal Cancer : Gastroenterology | June 2026

Introduction: Esophageal Adenocarcinoma is an aggressive malignancy strongly associated with chronic gastroesophageal reflux disease and exposure to acidic bile reflux. Despite advances in multimodal therapy, chemotherapy resistance remains a major barrier to durable disease control and survival. Problem Statement: Resistance to platinum-based chemotherapy in esophageal adenocarcinoma is poorly understood, particularly the molecular pathways linking reflux-induced injury to tumour stemness and treatment failure. The transcription factor SOX9 has emerged as a key regulator of tumour plasticity and chemoresistance, but direct therapeutic targeting has remained difficult because of its “undruggable” nature. Summary: This translational study identified activation of the SOX9 pathway as a central driver of chemoresistance in esophageal adenocarcinoma and demonstrated that targeting the redox function of APE1 can reverse this resistant phenotype. RNA sequencing analyses revealed strong enrichment of SOX9-associated transcriptional signatures in esophageal adenocarcinoma tissues, particularly in patients with poor relapse-free survival. Using reflux-mimicking acidic bile salt exposure models, the investigators demonstrated that APE1-dependent redox signaling activates and stabilizes SOX9 protein expression. This effect persisted during oxaliplatin exposure, suggesting a direct mechanistic link between reflux biology and chemotherapy resistance. Importantly, both genetic knockdown and pharmacologic inhibition of APE1 redox activity suppressed SOX9 signaling. The study identified the APE1 redox-specific inhibitor APX2009 as a potential therapeutic strategy capable of disrupting this pathway. Mechanistically, SOX9 activation promoted expression of ALDH1A1, a stemness-associated marker linked to chemoresistance and tumour persistence. The biological findings were consistently validated across multiple advanced experimental systems, including organotypic cultures, tumour spheroids, patient-derived organoids, genetically engineered mouse models and patient-derived xenografts. Clinically relevant co-overexpression of APE1 and SOX9 was confirmed in both murine and human esophageal adenocarcinoma specimens, strengthening the translational significance of the pathway. Most importantly, combining APX2009 with oxaliplatin in patient-derived xenograft models significantly enhanced chemotherapy response and reduced SOX9 expression, supporting the therapeutic feasibility of this approach. The study is highly relevant because it provides a biologically coherent explanation for why reflux-associated esophageal adenocarcinoma develops profound resistance to systemic therapy. Rather than attempting to directly inhibit SOX9 itself, the investigators successfully targeted an upstream regulatory mechanism controlling SOX9 stability and activation. This represents an attractive therapeutic paradigm because transcription factors involved in stemness and lineage plasticity are frequently difficult to inhibit directly. The work also highlights the broader importance of redox biology in gastrointestinal carcinogenesis and treatment resistance. Clinically, these findings may ultimately support biomarker-driven therapeutic stratification using APE1/SOX9 signatures to identify patients likely to benefit from combination redox-targeted therapy. Future studies will need to validate APX2009 in larger clinical settings and determine whether APE1 inhibition can synergize with immunotherapy or radiation therapy in esophageal adenocarcinoma. Overall, this study identifies the APE1–SOX9 signaling axis as a critical mediator of reflux-driven chemoresistance in esophageal adenocarcinoma and introduces APE1 redox inhibition as a promising strategy to overcome treatment resistance and improve therapeutic response.