Gastric Tissues Research Articles

High Expression of CLDN 18.2 is Associated with Poor Disease-Free Survival of HER-2 Positive Gastric Cancer.

Anti-claudin (CLDN) 18.2 therapy has been proven to be effective in treating advanced gastric cancer with negative human epidermal growth factor receptor 2 (HER-2). This study purposed to investigate the relationship of CLDN 18.2 expression with prognosis of HER-2-positive gastric cancer patients. To investigate the expression of claudin (CLDN) 18.2 in Human epidermal growth factor receptor 2 (HER-2) positive gastric cancer patients after radical resection and its relationship with gastric cancer prognosis. A total of 55 postoperative HER-2-positive gastric cancer patients were included in this study. CLDN 18.2 protein was detected by immunohistochemistry, and detailed clinical and pathological information was collected. Factors considered potentially important in the univariate analysis were included in the multivariate analysis, which involved COX regression to find the independent prognostic factors affecting disease-free survival (DFS). Immunohistochemistry showed that different levels of CLDN 18.2 protein were expressed in HER-2 positive gastric cancer tissues, and the Chi-square analysis showed that the expression level of CLDN 18.2 was significantly correlated with the lymph node stage. Higher expression levels of CLDN 18.2 were found in patients with lymph node positivity and were associated with poor prognosis in HER-2-positive gastric cancer patients. Gastric cancer patients with low and high expressions of CLDN 18.2 had postoperative median DFS of 38.5 months (95% confidence interval (CI) 28.8-48.2 months) and 12.1 months (95% CI, 11.7-41.0 months), respectively. High expression of CLDN 18.2 in HER-2 positive gastric cancer is associated with poor prognosis, and the optimal treatment mode for this population is worth exploring after the approval of anti-CLDN 18.2 drugs.

Video-fluorescence navigation by PpIX and tissue saturation measurement during surgical resection of gastric malignant tumor

SignificanceThe quality of the anastomosis is an important factor influencing the outcome of the surgical operation. Since it provides a reliable connection of sutured biological tissues, it is necessary to control the consistency of the anastomosis in order to prevent complications after the operation. Fluorescence diagnostics makes it possible to determine the localization of the tumor and residual pathological tumor tissues after resection by the intensity of the photosensitizer fluorescence accumulated in tissue, which can be missed during visual examination. ApproachFluorescence diagnostics was performed using a diode laser with a wavelength of 635 nm, which is at the absorption peak of the photosensitizer protoporphyrin 9 (PpIX). The assessment of the StO2 level was carried out spectroscopically using white broadband radiation. ResultsThe tissue blood supply was assessed. Patients with stomach resection underwent fluorescent diagnostics using PpIX. The localization of the tumor and pathological tumor sites after partial resection of the stomach was determined. The change in the level of StO2 at each stage of the operation was determined. ConclusionsFluorescent diagnostics using PpIX and joint determination of StO2 by diffuse scattering spectroscopy improved the quality of tumor resection and assessed the state of gastric tissue blood supply in real time.

Biphasic Regulation of Apoptosis Following Gastric Irreversible Electroporation Using Tissue Immunohistochemistry of Activated Caspase-3 with TUNEL Method.

The regulation of apoptosis is the primary goal of ablation therapy. Irreversible electroporation (IRE) is a promising non-thermal tissue ablation-based therapy that induces apoptosis by manipulating electrical conditions. This study aimed to investigate IRE-induced gastric tissue apoptosis in response to changes in the electric field intensity, followed by the repair process. Among the 52 rats used in this study, 24 were used to explore apoptosis, and 28 were used to study regeneration. The apoptosis-to-necrosis ratio of the electrical field strength was evaluated using terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling and caspase-3 immunohistochemistry. The size of IRE-induced ulcers in the gastric tissue continuously increased with increasing electrical intensity (r2 = 0.830, p < 0.001). The level of apoptosis gradually decreased after peaking at 200 V (1000 V/cm). The size of the 400 V-ablated ulcers continued to decrease, and they were not visible by day 14. The proliferation and migration of epithelial cells with fibroblasts were observed on day 3 and augmented on day 7 post-ablation. This investigation demonstrated the biphasic activation of apoptosis with respect to the electrical field strength. Visually and histologically, IRE-induced gastric ulcers demonstrated complete tissue regeneration after two weeks.

The long intergenic non-coding RNA LINC01140 modulates gastric cancer phenotypes and cancer cell lines aggressiveness

BackgroundLong-intergenic non-protein coding gene 01140 (LINC01140) a long non-coding RNA is highly expressed in various cancers. However, its biological functions in gastric cancer progression is still unknown. MethodTo elucidate LINC01140 function, 70 GC tumor samples and 30 normal gastric tissues were collected. LINC01140 expression level were determined by qRT-PCR analysis and correlated with different clinico-pathological parameters. Then we tried to see the impact of LINC01140 on gastric cell line aggressiveness by knocking down the target gene and performing cell viability assay, migration assay and invasive capacity of the cell lines along with immunoblotting to check several protein levels. ResultLINC01140 RNA is found to be positively correlated with FGF9 and significantly up regulated in GC tissues. LINC01140 knockdown inhibited the viability, migratory capacity and invasive capacity of AGS cells. LINC01140 targets miR-140–5p, while miR-140–5p targeted FGF9 to form lncRNA–miRNA-mRNA axis. The affect of miR-140–5p inhibition on gastric cancer cell aggressiveness were opposite to those of LINC01140 or FGF9 knockdown. Additionally, inhibition partially reversed the effects of LINC01140 knockdown on FGF9 protein levels, gastric cancer cell phenotypes. ConclusionLINC01140, miR-140–5p and FGF9 form a lncRNA-miRNA-mRNA axis that modulates the gastric cancer phenotypes and in turn affects gastric cancer cell aggressiveness.

A Case of Gastric Mucosa-Associated Lymphoid Tissue Lymphoma with Special Endoscopic Morphology

A Case of Gastric Mucosa-Associated Lymphoid Tissue Lymphoma with Special Endoscopic Morphology

ScRNA-seq of gastric cancer tissues reveals differences in the immune microenvironment of primary tumors and metastases.

Gastric carcinoma (GC) is regarded as one of the deadliest cancer characterized by diversity and haste metastasis and suffers limited understanding of the spatial variation between primary and metastatic GC tumors. In this project, transcriptome analysis on 46 primary tumorous, adjacent non-tumorous, and metastatic GC tissues was performed. The results demonstrated that metastatic tumorous tissues had diminished CD8+ T cells compared to primary tumors, which is mechanistically attributed to being due to innate immunity differences represented by marked differences in macrophages between metastatic and primary tumors, particularly those expressing ApoE, where their abundance is linked to unfavorable prognoses. Examining variations in gene expression and interactions indicated possible strategies of immune evasion hindering the growth of CD8+ T cells in metastatic tumor tissues. More insights could be gained into the immune evasion mechanisms by portraying information about the GC ecosystem.

Does crural repair with biosynthetic mesh improve outcomes of revisional surgery for recurrent hiatal hernia?

BackgroundLaparoscopic revisional surgery for recurrent hiatal hernia (HH) is technically demanding. Re-recurrences are common and esophageal hiatus mesh reinforcement might improve durability of the repair, thus minimizing the risk of re-herniation.PurposeAssess safety and effectiveness of simple suture repair (no mesh group) vs. crural augmentation with a biosynthetic absorbable mesh (mesh group) in patients with recurrent HH.MethodsObservational retrospective study from September 2012 to December 2022. Only patients undergoing redo surgery for previous failures of hiatal hernia repair were enrolled. Surgical failure was defined as symptomatic recurrent HH with > 2 cm of gastric tissue above the diaphragmatic impression at upper gastrointestinal endoscopy and/or swallow study. Gastro-Esophageal Reflux Disease Health-Related Quality of Life (GERD-HRQL) and Short Form-36 (SF-36) questionnaires were used to assess and preoperative and postoperative symptoms and quality of life.ResultsOne hundred four patients were included. Overall, 60 patients (57.7%) underwent mesh-reinforced cruroplasty, whereas 44 (42.3%) underwent simple suture cruroplasty. Mesh and no mesh groups had similar baseline demographics, symptoms, prevalence of esophagitis and Barrett’s esophagus, and HH size. A composite crural repair was most commonly performed in the mesh group (38.3% vs. 20.5%; p = 0.07). In addition to cruroplasty, most patients (91%) underwent a Toupet fundoplication. The 90-day postoperative complication rate was 8.6%, and there was no mortality. Recurrent HH was diagnosed in 21 patients (20.2%) with a clinical trend toward reduced incidence in the mesh group (16.7% vs. 25%; p = 0.06). Compared to baseline, there was a statistically significant improvement of median GERD-HRQL score (p < 0.01) and all SF-36 items (p < 0.01).ConclusionsLaparoscopic revisional surgery for recurrent HH is safe and effective. Selective use of biosynthetic mesh may protect from early recurrence and has the potential to reduce re-herniation in the long-term.

Effect of vitamin D3 and a stinging nettle extract on the gastric tissue of rats administered with trinitrobenzene sulfonic acid.

Inthis study, the effects ofvitaminD3 (Vit.D) and astinging nettle [Urtica dioicaL. (UD)] extract were examined using histopathological and immunohistochemical methods inthe stomach tissues ofan experimentally created rat model ofCrohn's disease (CD). The CD model was created using trinitrobenzene sulfonic acid (TNBS). The animals inthe study were divided into control, TNBS, TNBS+Vit. D, and TNBS+UD groups. Atthe end ofthe experiment, the animals were euthanised and their stomach tissues were evaluated for necrosis, degeneration, apoptosis, and inflammation. Additionally, animmunohistochemical method was applied todetermine the somatostatin (SSTR), aquaporin-1 (AQP-1), caspase-3, and tumour necrosis factor-alpha (TNF-α) immunoreactivity inthe gastric tissues. Inthe evaluations, degenerative and necrotic changes and mononuclear cell infiltration areas were observed intheTNBS group, but such changes could beimproved with Vit. D and UD applications. The results suggest that the combination ofthe Vit.D and UD extract may have aprotective and therapeutic role inmitigating TNBS-induced damage tothe gastric tissues, potentially through theregulation ofSSTR, AQP-1, caspase-3, and TNF-α expression. This indicates apromising avenue for further research and the exploration ofthese compounds inthecontext ofgastrointestinal health.

Construction of Magnolol Nanoparticles for Alleviation of Ethanol-Induced Acute Gastric Injury.

Ethanol (EtOH) has been identified as a potential pathogenic factor in gastric ulcer development primarily due to its association with gastric injury and excessive production of reactive oxygen species. Magnolol (Mag), the principal active compound in Magnolia officinalis extract, is well studied for its notable anti-inflammatory and antioxidant properties. However, its limited solubility, propensity for agglomeration, and low absorption and utilization rates significantly restrict its therapeutic use. This study aims to overcome these challenges by developing a Mag nanoparticle system targeting the treatment and prevention of EtOH-induced gastric ulcers in mice. Utilizing a click chemistry approach, we successfully synthesized this system by reacting thiolated bovine serum albumin (BSA·SH) with Mag. The in vitro analysis revealed effective uptake of the BSA·SH-Mag nanoparticle system by human gastric epithelial cells (GES-1), showcasing its antioxidant and anti-inflammatory capabilities. Additionally, BSA·SH-Mag exhibited gradual disintegration and release in simulated gastric fluid, resulting in a notable reduction of oxidative stress in gastric tissues and mucosal tissue repair and effectively reducing inflammatory expression. Furthermore, BSA·SH-Mag attenuated EtOH-induced gastric inflammation by decreasing the level of NOX4 protein expression and augmenting the level of Nrf2 protein expression. In conclusion, our findings indicate that BSA·SH-Mag represents a promising candidate as an oral therapeutic for gastric ulcer treatment.

TOB1 modulates neutrophil phenotypes to influence gastric cancer progression and immunotherapy efficacy.

The ErbB-2.1(TOB1) signaling transducer protein is a tumor-suppressive protein that actively suppresses the malignant phenotype of gastric cancer cells. Yet, TOB1 negatively regulates the activation and growth of different immune cells. Understanding the expression and role of TOB1 in the gastric cancer immune environment is crucial to maximize its potential in targeted immunotherapy. This study employed multiplex immunofluorescence analysis to precisely delineate and quantify the expression of TOB1 in immune cells within gastric cancer tissue microarrays. Univariate and multivariate Cox analyses were performed to assess the influence of clinical-pathological parameters, immune cells, TOB1, and double-positive cells on the prognosis of gastric cancer patients. Subsequent experiments included co-culture assays of si-TOB1-transfected neutrophils with AGS or HGC-27 cells, along with EdU, invasion, migration assays, and bioinformatics analyses, aimed at elucidating the mechanisms through which TOB1 in neutrophils impacts the prognosis of gastric cancer patients. We remarkably revealed that TOB1 exhibits varying expression levels in both the nucleus (nTOB1) and cytoplasm (cTOB1) of diverse immune cell populations, including CD8+ T cells, CD66b+ neutrophils, FOXP3+ Tregs, CD20+ B cells, CD4+ T cells, and CD68+ macrophages within gastric cancer and paracancerous tissues. Significantly, TOB1 was notably concentrated in CD66b+ neutrophils. Survival analysis showed that a higher density of cTOB1/nTOB1+CD66b+ neutrophils was linked to a better prognosis. Subsequent experiments revealed that, following stimulation with the supernatant of tumor tissue culture, the levels of TOB1 protein and mRNA in neutrophils decreased, accompanied by enhanced apoptosis. HL-60 cells were successfully induced to neutrophil-like cells by DMSO. Neutrophils-like cells with attenuated TOB1 gene expression by si-TOB1 demonstrated heightened apoptosis, consequently fostering a malignant phenotype in AGS and HCG-27 cells upon co-cultivation. The subsequent analysis of the datasets from TCGA and TIMER2 revealed that patients with high levels of TOB1 combined neutrophils showed better immunotherapy response. This study significantly advances our comprehension of TOB1's role within the immune microenvironment of gastric cancer, offering promising therapeutic targets for immunotherapy in this context.

Co-targeting CD47 and VEGF elicited potent anti-tumor effects in gastric cancer

BackgroundCD47, serving as an intrinsic immune checkpoint, has demonstrated efficacy as an anti-tumor target in hematologic malignancies. Nevertheless, the clinical relevance of CD47 in gastric cancer and its potential as a therapeutic target remains unclear.MethodsThe expression of CD47 in clinical gastric cancer tissues was assessed using immunohistochemistry and Western blot. Patient-derived cells were obtained from gastric cancer tissues and co-cultured with macrophages derived from human peripheral blood mononuclear cells. Flow cytometry analyses were employed to evaluate the rate of phagocytosis. Humanized patient-derived xenografts (Hu-PDXs) models were established to assess the efficacy of anti-CD47 immunotherapy or the combination of anti-CD47 and anti-VEGF therapy in treating gastric cancer. The infiltrated immune cells in the xenograft were analyzed by immunohistochemistry.ResultsIn this study, we have substantiated the high expression of CD47 in gastric cancer tissues, establishing a strong association with unfavorable prognosis. Through the utilization of SIRPα-Fc to target CD47, we have effectively enhanced macrophage phagocytosis of PDCs in vitro and impeded the growth of Hu-PDXs. It is noteworthy that anti-CD47 immunotherapy has been observed to sustain tumor angiogenic vasculature, with a positive correlation between the expression of VEGF and CD47 in gastric cancer. Furthermore, the successful implementation of anti-angiogenic treatment has further augmented the anti-tumor efficacy of anti-CD47 therapy. In addition, the potent suppression of tumor growth, prevention of cancer recurrence after surgery, and significant prolongation of overall survival in Hu-PDX models can be achieved through the simultaneous targeting of CD47 and VEGF using the bispecific fusion protein SIRPα-VEGFR1 or by combining the two single-targeted agents.ConclusionsOur preclinical studies collectively offer substantiation that CD47 holds promise as a prospective target for gastric cancer, while also highlighting the potential of anti-angiogenic therapy to enhance tumor responsiveness to anti-CD47 immunotherapy.

Hsa_circTCF25 Facilitates Oncogenesis in Gastric Cancer Cells by Modulating miR-149 Expression.

Circular RNA (circRNA) is related to gastric carcinogenesis and progression. This study explored the effects of circTCF25 on gastric cancer cell proliferation, migration, invasion, and cancer stem cell markers, as well as the potential network of circTCF25-miR and miR-149. circTCF25 expression was detected in tissue specimens and cells by real-time quantitative reverse transcription polymerase chain reaction. Cell Counting Kit-8 and transwell assays were used to measure the effects of circTCF25 knockdown on proliferation, migration and invasion. The potential network of circTCF25 was analyzed using bioinformatic analysis. circTCF25 was overexpressed in human gastric cancer tissues, and a series of cancer cell lines, and was associated with shorter overall survival. Interfering with circTCF25 reduced gastric cancer cell proliferation, migration, invasion and expression of cancer stem cell markers. CircTCF25 reduced expression of miR-149, apparently by acting as a miR-149 sponge. A new circTCF25-miR-149 competitive endogenous RNA network in gastric cancer was constructed, and most core genes were associated with the malignant growth and metastatic behavior of gastric cancer. circTCF25 may have prognostic value and an oncogenic role in gastric cancer. A circTCF25-miR-149 RNA regulatory network was established which may provide novel biomarkers or potential therapeutic targets for treating gastric cancer.

Matrix metalloproteinase-1 as a potential biomarker for early gastric cancer detection and its effect on gastric cancer cell proliferation and migration

The present study aimed to investigate the association between matrix metalloproteinase-1 (MMP-1) and early gastric cancer (EGC), while also evaluating the effect of MMP-1 on gastric cancer cell proliferation and migration. Transcriptome RNA sequencing and database analysis were conducted to assess the relationship between MMP-1 expression and EGC. Differences in MMP-1 expression between clinical EGC samples and paracancerous tissues were detected using fluorescence quantitative polymerase chain reaction (PCR). In N87 gastric cancer cells, changes in proliferation- and migration-related indicator expression were determined. Gene sequencing revealed differential expression of MMP-1 in early and advanced gastric cancers. Furthermore, enhanced MMP-1 expression was observed in early and advanced gastric cancer tissues, exhibiting a positive correlation with the malignant phenotype in gastric cancer cell lines. Fluorescence quantitative PCR revealed considerably higher MMP-1 expression in EGC tissues than in paracancerous tissues. CCK8 and EdU assays demonstrated a significant increase in N87 cell proliferation on MMP-1 upregulation and a decrease on its downregulation. The scratch assay results demonstrated a corresponding enhancement in N87 cell migratory capacity with MMP-1 upregulation, which was attenuated on its downregulation. Western blot experiments revealed a decrease in the expression of the epithelial-mesenchymal transition-related protein E-cadherin after MMP-1 upregulation, while vimentin expression significantly increased. Conversely, the downregulation of MMP-1 led to opposite outcomes. Overall, MMP-1 emerges as a potential biomarker for EGC diagnosis and plays a crucial role in the regulation of N87 gastric cancer cell proliferation and migration.

Analysis of endoscopic and pathological features of 6961 cases of gastric cancer

Gastric cancer (GC) stage and tissue differentiation affect treatment efficacy and prognosis, highlighting the importance of understanding the risk factors that affect these parameters. Therefore, this study analyzed risk factors affecting the GC stage and differentiation and the relationships between the cancer site and the sex and age of the patient. We collected clinical data from 6961 patients with GC, including sex, age, endoscopic lesion location, and pathological differentiation. Patients were grouped based on GC stage (early or advanced), differentiation (well or poorly differentiated), and lesion site (upper stomach [cardia and fundus], middle stomach [gastric body], and lower stomach [gastric antrum]). Differences in sex, age, location, stage, and degree of differentiation were assessed based on these groupings. Univariate analysis revealed that the disease location and differentiation significantly differed based on the GC stage (P < 0.05), whereas sex, age, site, and stage significantly differed based on GC differentiation (P < 0.05). A multivariate analysis confirmed these factors as independent risk factors affecting GC. Moreover, lesion sites significantly differed between sexes (P < 0.05) and among age groups (P < 0.05). Although the effects of family history, lifestyle, and Helicobacter pylori infection status of the patients were not considered, this single-center retrospective study established independent risk factors for GC.Trial registration ChiCTR2200061989.

LncRNA WFDC21P interacts with SEC63 to promote gastric cancer malignant behaviors by regulating calcium homeostasis signaling pathway

BackgroundGastric cancer is currently estimated to be the fifth leading common cancer in the world, and responsible for about one million new cases and an estimated 769,000 cancer-related deaths each year. WFDC21P is long non-coding RNA and has been reported to play critical roles in serval types of cancer. Our research aims to investigate the biological effects and molecular mechanism of WFDC21P in gastric cancer.MethodsDatasets (GSE53137, GSE58828, and GSE109476) in GEO database were used to screen differential expressed lncRNAs in gastric cancer by online GEO2R analysis tool. Quantitative RT-PCR was used to verify the above prediction in ten pairs of gastric cancer and corresponding paracancerous tissues. Pan-cancer analysis was used to analyze the expression of WFDC21P in different types of cancer. Small interfering RNAs were used to WFDC21P knockdown. CCK-8 and colony formation assays were used to measure the proliferation and tumorigenesis abilities. Wound healing and Transwell assay were used to detect the migration and invasion abilities. Proteins that interact with WFDC21P were predicted by catRAPID database. RNA pull down and RNA Immunoprecipitation were used to confirm the interaction. Western blotting was used to detect the key proteins level in calcium homeostasis signaling pathway. Loss-of-function and rescue assays were used to evaluate the biological function of SEC63 at the background of WFDC21P silencing.ResultsWFDC21P was upregulated in gastric cancer tissues and cell lines. WFDC21P downregulation suppressed proliferation, tumorigenesis, migration, invasion, and promoted apoptosis in gastric cancer. SEC63 protein had the capability to bind with WFDC21P and the expression of SEC63 was regulated by WFDC21P. SEC63 was also upregulated in gastric cancer and exerted effects during tumor growth and metastasis.ConclusionsThis study confirmed that lncRNA WFDC21P aggravated gastric cancer malignant behaviors by interacting with SEC63 to regulate the calcium homeostasis signaling pathway.

Research Progress of Apoptosis Inhibitory Protein Survivin in Gastric Cancer

Survivin is an important member of the apoptosis inhibitory protein family, which plays an important role in suppressing apoptosis, promoting proliferation and vascular formation. The occurrence and development of tumors are related to apoptosis and imbalance of proliferation. Gastric cancer is the most common malignant tumor in the digestive system. Due to the inadequate symptoms of early symptoms, most of them have entered the middle and late stages during diagnosis. It is easy to relapse and metastasize. The mortality rate is high, which seriously endangers human health. Research have found that Survivin expresses high in gastric cancer tissue, participating in the proliferation of tumor cells, inhibiting apoptosis and the formation of blood vessels, and is of great significance to the diagnosis, judgment transfer and prognosis evaluation of gastric cancer, especially the value of combined with a number of indicators is greater. Therefore, finding an early diagnosis and judging the ideal tumor logo combination of the early diagnosis and judgment of the prognosis is important. This article reviews the biological characteristics of Survivin and its research progress in gastric cancer, so as to provide theoretical basis for the diagnosis of gastric cancer and new ideas for the successful prevention and treatment of tumors.

Profiling of Metabolites in a Fermented Soy Dietary Supplement Reinforces its Role in the Management of Intestinal Inflammation.

Gastro-AD (GAD) is a soy flour derived product that undergoes an industrial fermentation with Lactobacillus delbrueckii R0187 and has demonstrated clinical effects in gastroesophageal reflux and peptic ulcer symptom resolution. The aim of this study is to describe and link GAD's metabolomic profile to plausible mechanisms that manifest and explain the documented clinical outcomes. 1H NMR spectroscopy with multivariate statistical analysis is used to characterize the prefermented soy flour and GAD products. The acquired spectra are screened using various resources and the molecular assignments are confirmed using total correlation spectroscopy (TOCSY). Peaks corresponding to different metabolites are integrated and compared between the two products for relative changes. HPLC and GC are used to quantify some specific molecules. NMR analyses demonstrate significant changes in the composition of various assigned bioactive moieties. HPLC and GC analysis demonstrate deglycation of isoflavones after fermentation, resulting in estrogenically active secondary metabolites that have been previously shown to help to reduce inflammation. The identification of bioactive molecules, such as genistein and SCFAs, capable of modulating anti-inflammatory signaling cascades in the stomach's gastric and neuroendocrine tissues can explain the reported biological effects in GAD and is supported by in vivo data.

Abstract 4776: The role of angiogenesis in gastric tumorigenesis

Abstract Introduction: Gastric or stomach cancer remains one of the most lethal malignancies, with an estimated 1,089,103 new cases and 768,793 deaths worldwide in 2020. In the United States, it is estimated that there were 26,500 new cases and 11,130 deaths from stomach cancer in 2023. Unfortunately, despite improved treatment in recent years, ~65% of gastric cancer patients present with aggressive metastatic disease, and they die within one year of diagnosis. Therefore, the identification of newer and effective therapies to target the precancerous stages of the disease promises possibilities for the prevention of gastric cancer in patients harboring these lesions. Gastric metaplasia and dysplasia are precancerous lesions that often progress to gastric cancer. Since anti-VEGF-A anti-angiogenic agents have shown efficacy in advanced gastric cancer patients, we hypothesized that VEGF-A-mediated angiogenesis has a functional role in the pathogenesis of gastric metaplasia and dysplasia. Experimental Procedures: The Initial experiments were undertaken in human gastric metaplasia and dysplasia tissues and murine gastric metaplasia and dysplasia tissues collected from a well-established Helicobacter felis (H. felis) induced murine model of gastric tumorigenesis simulating human patients to detect angiogenesis (CD31/MVD) and identify angiogenic pathways using GeoMx DSP Spatial Proteomics and NanoString nCounter assay. Thereafter, further experiments were undertaken in the H. felis-induced murine model of gastric metaplasia and dysplasia, simulating human patients using VEGF-A hypo mice to determine the role of VEGF-A-induced angiogenesis in the progression of these lesions. Results and Conclusion: Although our results indicated angiogenesis and VEGF-A expression in both human and mouse gastric metaplasia and dysplasia, inhibition in the progression of the precancerous gastric lesions was observed in only 40% of the VEGF-A hypo mice, thereby suggesting that VEGF-A induced angiogenesis might not be the major angiogenic pathway in these precancerous lesions in every patient. A similar phenomenon is also seen in some gastric cancer patients. Citation Format: Venu Akkanapally, SUJIT BASU. The role of angiogenesis in gastric tumorigenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4776.

Abstract 5583: Helicobacter pylori induces the wee1, promoting immune suppressive in human gastric adenocarcinoma

Abstract Background: Gastric cancer (GC) is the fourth most common cause of cancer-related death worldwide. GC has a dismal 5-year survival rate of about 32%. Helicobacter pylori (H. pylori) infection is the strongest risk factor for gastric carcinogenesis. 75-90% of gastric cancer patients exhibit positive H. pylori serology. WEE1 is a nuclear kinase that regulates cell cycle progression by inhibiting cyclin-dependent kinases. Methods &amp; Results: Analysis of non-cancer normal stomach tissue (n=360) and human GC samples (n=1221) identified that WEE1 mRNA was significantly overexpressed in GC. Using immunohistochemistry (IHC) staining in 41 normal and 44 GC human samples, the data indicated that WEE1 protein was significantly overexpressed in GC. Western blot and immunofluorescence (IF) staining confirmed that H. pylori infection induces WEE1 overexpression in GC cells with an unexpected cytosolic localization of WEE1 in GC cells. Tff1 knockout GC mouse model (Tff1-/-) was infected with mouse-adapted H. pylori strain PMSS1. Western blot and immunohistochemistry data demonstrated that H. pylori infection induced WEE1 expression in Tff1 -/- HGD/cancer mouse gastric tissues compared to control Tff1 -/- mouse stomach. To study how H. pylori infection induces WEE1 in GC, analysis from miRTAR, Target Scan, and miRDB demonstrated that WEE1 is predicted to be targeted by miR-497-5p. Using qRT-PCR analysis, we assessed 30 normal and 30 GC human tissue samples, revealing a pronounced downregulation of miR-497-5p in GC specimens. Western blot analysis confirmed that the restoration of miR-497-5p in GC cells markedly reduced WEE1 protein expression. Interestingly, H. pylori infection further decreased miR-497-5p levels in GC cells, upregulating WEE1 protein expression. Since the miR-497-5P host gene promoter region contains CpG islands, we confirmed that treatment with 5 Azacytidine (demethylating agent) or DNMT1 knockdown induced expression of miR-497-5p with decreased WEE1 level in GC cells. Furthermore, our preliminary results indicate that aberrant WEE1 overexpression in GC demonstrates a significant positive correlation with immune-suppression gene signatures, underscoring its predictive value for unfavorable patient survival outcomes in GC. Using the TFF1 knockout mouse GC model, we found that WEE1 inhibition notably decreases the number and activation of CD4+ and CD8+ T cells in neoplastic gastric tissues. These findings also indicate a crucial relationship between WEE1 and the immunosuppressive microenvironment in GC, establishing WEE1 as a promising therapeutic target to enhance therapeutic efficacy and overcome immunotherapy resistance in GC. Conclusions: Our findings demonstrated a novel mechanism in which H. pylori activates the WEE1 in GC, promoting an immune suppressive microenvironment. WEE1 inhibition with immunotherapy could be a promising therapeutic method for GC patients. Citation Format: Md Obaidul Islam, Krishnapriya Thangaretnam, Heng Lu, Dunfa Peng, Nadeem Sidiq Bhat, Mohammed Soutto, Wael El-Rifai, Zheng Chen. Helicobacter pylori induces the wee1, promoting immune suppressive in human gastric adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5583.

Abstract 638: FGFR4 mediates nuclear accumulation of NRF2 by binding to P62 in gastric cancer

Abstract Background: Helicobacter pylori (H. pylori) is the major cause of gastric cancer. Fibroblast growth factor receptor 4 (FGFR4) is a member of the highly conserved tyrosine kinase family known to be activated in cancer. Nuclear Factor Erythroid 2-Related Factor 2 (NRF2), a transcription factor, is essential for the antioxidant response and exhibits cytoprotective properties against cellular stress and oxidative damage. This study investigates the novel functions of FGFR4 and its role in regulating the antioxidant response in gastric tumorigenesis. Methods: We used public datasets, gastric tissues from mice and human, and gastric cancer cell lines. In vitro and in vivo H. pylori infections were performed. Western blot, RT-qPCR, Immunofluorescence, flow cytometry, Immunohistochemistry, Immunoprecipitation, Proximity ligation assay and Luciferase reporter assays were performed. Results: The analysis of a public dataset revealed that overexpression of FGFR4 is associated with an oxidative stress signature and poor survival. Gene set enrichment analysis (GSEA) showed that tissue samples with high FGFR4 levels had an enrichment of NRF2 signature genes. In vitro cell models infected with H. pylori showed an increase in reactive oxygen species (ROS). Knockdown of FGFR4 resulted in significant reductions in NRF2 protein and transcriptional activity, leading to increased ROS levels and DNA damage. Immunofluorescence analysis using various models confirmed that FGFR4 knockdown reversed the accumulation of NRF2 in the nucleus. Dysplastic and neoplastic gastric lesions in the TFF1-KO mouse model exhibited high levels of both FGFR4 and NRF2. Pharmacologic inhibition or knockdown of FGFR4 significantly decreased NRF2 levels, as well as the size and number of gastric cancer spheroids. Mechanistically, elevated levels of P62 protein were associated with FGFR4 expression. Binding between FGFR4 and P62 proteins, which competes with NRF2-KEAP1 interaction, was detected using immunoprecipitation and proximity ligation assay. Immunohistochemistry analysis on a tissue microarray showed increased FGFR4 immunostaining in HGD/Cancer samples compared to adjacent normal samples, and this increase correlated with an increase in NRF2 and P62 levels. Conclusion: These findings revealed that FGFR4 has a distinct functional role in promoting gastric carcinogenesis. FGFR4 binds to P62 to inhibit the interaction between NRF2 and KEAP1, allowing NRF2 to avoid degradation facilitating its translocation and accumulation in the nucleus. The use of FGFR4 inhibitors is a viable treatment option that warrants further research in patients with gastric cancer. Citation Format: Nadeem S. Bhat, Mohammed Soutto, Xing Zhang, Zheng Chen, Shoumin Zhu, Selma Maacha, Melanie Genoula, Dunfa Peng, Heng Lu, Oliver G McDonald, Xi Steven Chen, Longlong Cao, Zekuan Xu, Wael El-Rifai. FGFR4 mediates nuclear accumulation of NRF2 by binding to P62 in gastric cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 638.