Immunotherapy For Gastric Cancer Research Articles

Combination of IFN-gamma with STING agonist and PD-1 immune checkpoint blockade: a potential immunotherapy for gastric cancer.

Suppression of the cGAS-STING pathway is an immune escape mechanism in cancer cells. The critical role of this pathway in gastric cancer (GC) is not fully understood. Herein, we evaluated the effect of the interferon-gamma (IFN-gamma), STING agonist, PD-1 immune checkpoint blockade, and their combination on the cGAS-STING pathway in GC. Expression of cGAS and STING in tumor tissue samples and adjacent normal tissue (ANT) biopsies of fifty new GC patients was evaluated by quantitative real-time PCR (qRT-PCR). Moreover, cGAS and STING expression levels were examined in Peripheral Blood Mononuclear Cells (PBMC) samples of forty GC patients and twenty-five healthy subjects. The apoptosis rate of cancer cells was analyzed by Annexin V-FITC/PI. Cell proliferation was measured by the BrdU assay. Also, IFN-β levels were evaluated in the supernatants of the treated groups. The cGAS expression was decreased in patients with distant metastasis. Co-cultures treated with IFN-gamma showed an elevated level of cGAS and STING expressions in PBMC and cancer cells. The rate of apoptosis increased in all the treatment groups. In addition, the rate of proliferation in PBMCs increased in different treated groups. The main role of PBMCs in cytotoxicity was determined by a comparative analysis of the viability of cells treated with all treatments, both with and without PBMCs. The production of IFN-β was elevated in all treated groups. The current study suggests that a combination therapy using IFN-gamma, STING agonist, and anti-PD-1 antibody can provide a promising approach to the treatment of GC.

Immunotherapy in Gastric Cancer—Choosing Methods or Results

Immunotherapy in Gastric Cancer—Choosing Methods or Results

Integrated Analysis Construct a Tumor-Associated Macrophage Novel Signature with Promising Implications in Predicting the Prognosis and Immunotherapeutic Response of Gastric Cancer Patients.

Gastric cancer (GC) remains one of the most prevalent malignant tumors worldwide. At present, tumor-associated macrophages (TAMs) are essential in the progression, metastasis, and drug resistance of tumors. Therefore, TAMs can be a crucial target for tumor treatment. We intended to investigate the TAM characteristics in GC and develop a risk signature based on TAM to predict the prognosis of GC patients. The single-cell RNA sequencing (scRNA-seq) and bulk RNA-seq data were acquired from a publicly available database. We utilized the Seurat pipeline to process the scRNA-seq data and determine TAM cell types using marker genes. Univariate Cox regression analysis was utilized to examine TAM-related prognostic genes, and then we employed Lasso-Cox regression analysis, and Multivariate Cox regression analysis established a novel risk profile to forecast the clinical value of the model with a new nomogram combining risk profiles and clinicopathological characteristics. The current study employed scRNA-seq data to identify five TAM clusters in GC, among which four were significantly associated with GC prognosis. Accordingly, we further developed a TAM-related risk signature utilizing nine genes. After evaluation, our model accurately predicted the prognosis of gastric cancer. Generally, GC patients with low TAMS scores exhibited a more favorable prognosis, greater benefits from immunotherapy, and higher levels of immune cell infiltration. The prognosis of GC can be effectively predicted by TAM-based risk signatures, and the signature may provide a new perspective for comprehensively guiding clinical diagnosis, prediction, and immunotherapy for gastric cancer.

Bioinformatic Analysis and Experimental Validation of HMGA2-AS1 as a Prognostic Biomarker Associated with Immune Infiltration in Gastric Cancer.

Natural antisense long noncoding RNAs (lncRNAs) have the ability to modulate the expression of their corresponding sense genes. Consequently, any dysregulation of these lncRNAs can contribute to the development of pathological processes. The ambiguity surrounding the role of HMGA2-AS1 in gastric cancer (GC) requires further investigation. The aim of this study was to examine the involvement of HMGA2-AS1 in GC. The Kaplan-Meier method, Cox regression analysis, gene set enrichment analysis (GSEA), and immune infiltration analysis were used in this study. These methods were used to evaluate the relationship between clinical characteristics and HMGA2-AS1 expression, prognostic factors, and the significant functional impact of HMGA2-AS1. HMGA2-AS1 levels in GC cell lines were validated using quantitative real-time polymerase chain reaction (qRT-PCR). In patients diagnosed with GC, a significant correlation was observed between high expression of HMGA2-AS1 and the T stage (p = 0.01). Furthermore, the high expression of HMGA2- AS1 was identified as a prognostic indicator for poorer OS (p = 0.004), PFS (p = 0.006), and DSS (p = 0.011). Furthermore, the expression of HMGA2-AS1 (p < 0.001) demonstrated an independent association with OS in patients with GC. The presence of a low expression phenotype of HMGA2-AS1 was associated with differential enrichment of various pathways, including the focal adhesion-PI3K-Akt-mTOR signaling pathway, focal adhesion, ECM glycoproteins, MET promoting cell motility, among others. Furthermore, the expression of HMGA2-AS1 exhibited correlations with B cells, CD56 bright cells, and TFH and Th17 cells. Furthermore, GC cell lines demonstrated significantly higher expression of HMGA2-AS1. Elevated expression of HMGA2-AS1 in GC patients exhibited a significant correlation with unfavorable survival outcomes and increased immune infiltration. This suggests that HMGA2- AS1 holds promise as a potential prognostic biomarker and target for immunotherapy in GC.

Effect of Epstein-Barr Virus Infection on the Treatment of Gastric Cancer in Tumor Immunotherapy

Gastric cancer is one of the biggest medical problems in the world today, and it is also a huge medical challenge for human beings. The main challenge is the complexity of the limitations of gastric cancer itself. At present, the efficacy of single-drug immune checkpoint inhibitors in treatment is not clear. It can be found in previous cases that Epstein-Barr virus positive gastric cancer patients have significantly higher response to PD-1 antibodies than the overall patients, from which it can be found that EBV infection can play an important role in gastric cancer immunotherapy. The purpose of this study was to investigate the effect of Epstein-Barr virus infection on gastric cancer and analyze specific clinical cases. The results showed that patients infected with Epstein-Barr virus had obvious advantages in the treatment of gastric cancer, which was significantly correlated with the expression of PD-L1 and EBV (+). This study highlights the potential benefits of Epstein-Barr virus infection in the treatment of gastric cancer, providing new insights into the development of future immunotherapy strategies. These findings will help to improve the treatment of gastric cancer patients, as well as to better understand the immune properties of gastric cancer and develop related vaccines. The significance of this study is that it provides a solid foundation for innovation in the treatment of gastric cancer.

Current status of neoadjuvant immunotherapy for the treatment of gastric cancer.

Gastric cancer is one of the most prevalent malignant tumors worldwide, characterized by high incidence and mortality rates. At present, comprehensive surgical treatment has enhanced the prognosis of locally advanced gastric cancer patients significantly. However, the postoperative recurrence rate remains high, and the long-term survival for patients is sub-optimal. In recent years, immunotherapy has garnered extensive attention as an innovative approach to the treatment of gastric cancer. Indeed, multiple studies have validated its therapeutic effects in advanced gastric cancer patients, leading to its incorporation into treatment guidelines. Currently, researchers are exploring the application of immunotherapy in the neoadjuvant setting globally in order to further adjust and refine neoadjuvant immunotherapy regimens for gastric cancer. This article summarizes the research progress and controversies associated with neoadjuvant immunotherapy in gastric cancer, aiming to optimize clinical benefits for gastric cancer patients undergoing this treatment approach. The retrieval methods of this study encompassed databases such as PubMed, Google Scholar, Web of Science, clinicaltrials.gov, etc. The retrieved articles included guidelines, consensus, meta-analyses, clinical trials, and reviews related to locally advanced gastric cancer published up to January 2024.

Gypenoside induces apoptosis by inhibiting the PI3K/AKT/mTOR pathway and enhances T-cell antitumor immunity by inhibiting PD-L1 in gastric cancer.

Introduction: Gypenoside is a natural extract of Gynostemma pentaphyllum (Thunb.) Makino, a plant in the Cucurbitaceae family. It has been reported to have antitumor effects on the proliferation, migration and apoptosis of various types of cancer cells. However, the use of gypenoside in the treatment of gastric cancer has not been studied. In the present study, we explored the therapeutic effect of gypenoside on gastric cancer and the potential molecular mechanism. Methods and Results: Our results showed that gypenoside induced apoptosis in HGC-27 and SGC-7901 cells in a time-dependent and dose-dependent manner. Network pharmacology analyses predicted that gypenoside exerts its therapeutic effects through the PI3K/AKT/mTOR signaling pathway. Furthermore, molecular docking and western blot experiments confirmed that gypenoside induced the apoptosis of gastric cancer cells through the PI3K/AKT/mTOR signaling pathway. In addition, network pharmacological analysis revealed that the common targets of gypenoside in gastric cancer were enriched in the immune effector process, PD-L1 expression, the PD-1 checkpoint pathway, and the Jak-STAT signaling pathway. Furthermore, molecular docking and western blot assays demonstrated that gypenoside could bind to STAT3 and reduce its phosphorylation. Thus, the transcription of PD-L1 was inhibited in gastric cancer cells. Moreover, coculture experiments of gastric cancer cells with gypenoside and primary mouse CD8+ T cells showed that gastric cancer cells treated with gypenoside could enhance the antitumor ability of T cells. Animal experiments confirmed the antitumor effect of gypenoside, and the expression of PD-L1 was significantly downregulated in the gypenoside-treated group. Conclusion: Gypenoside induced the apoptosis of gastric cancer cells by inhibiting the PI3K/AKT/mTOR pathway and simultaneously inhibited the expression of PD-L1 in gastric cancer cells, thus enhancing the antitumor immunity of T cells. This study provides a theoretical basis for applying gypenoside as a new therapeutic agent to enhance the efficacy of immunotherapy in gastric cancer.

Nursing of integrated traditional Chinese and Western medicine in a case of severe diabetic ketoacidosis complicated with intestinal obstruction and pneumonia caused by immunotherapy for gastric cancer

Nursing of integrated traditional Chinese and Western medicine in a case of severe diabetic ketoacidosis complicated with intestinal obstruction and pneumonia caused by immunotherapy for gastric cancer

Evaluating the influence of sarcopenia and myosteatosis on clinical outcomes in gastric cancer patients undergoing immune checkpoint inhibitor.

The development and progression of gastric cancer (GC) are closely linked to the nutritional status of patients. Although immunotherapy has been demonstrated to be clinically effective, the relationships of sarcopenia and myosteatosis with the use of immune checkpoint inhibitors (ICIs) in patients with gastric cancer remain to be characterized. To assess the effects of sarcopenia and myosteatosis on the clinical outcomes of patients with GC undergoing treatment with an ICI. We performed a retrospective study of patients who were undergoing immunotherapy for GC. For the evaluation of sarcopenia, the optimal cut-off value for the skeletal muscle index was established using receiver operating characteristic analysis of data obtained from pre-treatment computed tomography images at the L3 vertebral level. Myosteatosis was defined using the mean skeletal muscle density (SMD), with a threshold value of < 41 Hounsfield units (HU) for patients with a body mass index (BMI) < 25 kg/m² and < 33 HU for those with a BMI ≥ 25 kg/m². The log-rank test was used to compare progression-free survival (PFS) and overall survival (OS), and a Cox proportional hazard model was used to identify prognostic factors. Nomograms were developed to predict the PFS and OS of patients on the basis of the results of multivariate analyses. We studied 115 patients who were undergoing ICI therapy for GC, of whom 27.4% had sarcopenia and 29.8% had myosteatosis. Patients with sarcopenia or myosteatosis had significantly shorter PFS and OS than those without these conditions. Furthermore, both sarcopenia and myosteatosis were found to be independent predictors of PFS and OS in patients with GC administering an ICI. The prediction models created for PFS and OS were associated with C-indexes of 0.758 and 0.781, respectively. The presence of sarcopenia or myosteatosis is a reliable predictor of the clinical outcomes of patients with GC who are undergoing treatment with an ICI.

Immunotherapy in Gastric Cancer: A Review

Globally, gastric cancer (GC) ranks fourth in terms of cancer-related mortality. Patients diagnosed with advanced gastric cancer (AGC) frequently have a median survival around 12-15 months, depending to the therapy. Immunotherapy is becoming an essential therapeutic strategy in medical oncology, and it is projected to make major advances to the way gastric cancer cure. The phase III ATTRACTION-2 showed that nivolumab, a monoclonal antibody targeting programmed cell death 1 (PD-1), substantially increased overall survival (OS) in patients with advanced gastric cancer (AGC) when given as a third- or later-line treatment, as compared to a placebo. Furthermore, nivolumab in combination with 5-fluorouracil and platinum as a first-line treatment increased OS in patients with human epidermal growth factor receptor-2 (HER2)-negative AGC in the international phase III CheckMate-649 investigation. Pembrolizumab, an additional anti PD-1 antibody, when used with trastuzumab and cytotoxic chemotherapy as first line treatment, demonstrated a substantial enhancement in the overall response rate among patients diagnosed with HER2-positive AGC. Hence, immune checkpoint inhibitors (ICIs) are crucial in the present management of GC. Current research is actively investigating alternative treatment following ICI combination therapy, including ICI rechallenge or combination therapy with drugs that have distinct mechanisms of action. Several clinical trials are presently being done to employ immunotherapy as a treatment option in the perioperative and postoperative settings for patients with early gastric cancer, based on the success of immunotherapy in treating advanced gastric cancer (AGC). This article gives an overview of the recent breakthroughs in immunotherapy.

The prognostic value and potential immunotherapeutic efficacy of ACVR1 in treating gastric cancer.

The discovery of biomarkers has facilitated the treatment of cancer. At present, the relationship between activin A receptor type-1 (ACVR1) and gastric cancer is gradually discovered. The aim of this study was to explore the expression of ACVR1 in gastric cancer and its clinical significance, to study the relationship between ACVR1 and tumor microenvironment (TME) for the prognosis of gastric cancer, and to further identify new targets for immunotherapy in gastric cancer. ACVR1 was first selected as a study gene according to several cancer and gastric cancer public datasets. Its pancancer expression was explored using the UCSC Xena database. The expression level, prognosis, and clinicopathological features of ACVR1 in gastric cancer were analyzed using The Cancer Genome Atlas (TCGA) database. Immunohistochemistry (IHC)-based experiments were conducted to study the expression of ACVR1 at the protein level. The IHC data were analyzed for correlations between ACVR1 expression and various clinicopathological factors and prognosis. The correlation of this gene with the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, immune infiltration, immune checkpoints, drug therapy, tumor mutation burden (TMB), microsatellite instability (MSI), and mismatch repair (MMR) system was analyzed using R software. TCGA data showed that the expression of ACVR1 was higher in gastric cancer tissues than in paracancerous tissues. Moreover, the IHC experiments indicated that ACVR1 was upregulated in gastric cancer tissues at the protein level. Both univariate Cox and multivariate Cox results showed that the increase of ACVR1 was closely associated with tumor stage, size, lymph node metastasis, and age. High ACVR1 expression was linked to a poor prognosis of gastric cancer. The results also revealed that ACVR1 was closely related to suppressive immune cells and pathways. Analyses of immune checkpoints, antitumor drug, TMB, and immune microenvironment indicated that ACVR1 had an antitumor immune effect, promoting gastric cancer development and leading to poor immunotherapy. High ACVR1 expression can be used as an independent prognostic factor to predict the prognostic survival of patients with gastric cancer. ACVR1 expression in gastric cancer tissues was significantly correlated with immune infiltration and may thus serve as a potential therapeutic target for gastric cancer immunotherapy.

Comprehensive assessment of immune context and immunotherapy response via noninvasive imaging in gastric cancer.

BACKGROUNDThe tumor immune microenvironment can provide prognostic and therapeutic information. We aimed to develop noninvasive imaging biomarkers from computed tomography (CT) for comprehensive evaluation of immune context and investigate their associations with prognosis and immunotherapy response in gastric cancer (GC).METHODSThis study involved 2,600 patients with GC from 9 independent cohorts. We developed and validated 2 CT imaging biomarkers (lymphoid radiomics score [LRS] and myeloid radiomics score [MRS]) for evaluating the IHC-derived lymphoid and myeloid immune context respectively, and integrated them into a combined imaging biomarker [LRS/MRS: low(-) or high(+)] with 4 radiomics immune subtypes: 1 (-/-), 2 (+/-), 3 (-/+), and 4 (+/+). We further evaluated the imaging biomarkers' predictive values on prognosis and immunotherapy response.RESULTSThe developed imaging biomarkers (LRS and MRS) had a high accuracy in predicting lymphoid (AUC range: 0.765-0.773) and myeloid (AUC range: 0.736-0.750) immune context. Further, similar to the IHC-derived immune context, 2 imaging biomarkers (HR range: 0.240-0.761 for LRS; 1.301-4.012 for MRS) and the combined biomarker were independent predictors for disease-free and overall survival in the training and all validation cohorts (all P < 0.05). Additionally, patients with high LRS or low MRS may benefit more from immunotherapy (P < 0.001). Further, a highly heterogeneous outcome on objective response ​rate was observed in 4 imaging subtypes: 1 (-/-) with 27.3%, 2 (+/-) with 53.3%, 3 (-/+) with 10.2%, and 4 (+/+) with 30.0% (P < 0.0001).CONCLUSIONThe noninvasive imaging biomarkers could accurately evaluate the immune context and provide information regarding prognosis and immunotherapy for GC.

A novel biomarker associated with EBV infection improves response prediction of immunotherapy in gastric cancer

BackgroundNovel biomarkers are required in gastric cancer (GC) treated by immunotherapy. Epstein-Barr virus (EBV) infection induces an immune-active tumor microenvironment, while its association with immunotherapy response is still controversial. Genes underlying EBV infection may determine the response heterogeneity of EBV + GC. Thus, we screened hub genes associated with EBV infection to predict the response to immunotherapy in GC.MethodsPrognostic hub genes associated with EBV infection were screened using multi-omic data of GC. EBV + GC cells were established and confirmed by EBV-encoded small RNA in situ hybridization (EBER-ISH). Immunohistochemistry (IHC) staining of the hub genes was conducted in GC samples with EBER-ISH assay. Infiltrating immune cells were stained using immunofluorescence.ResultsCHAF1A was identified as a hub gene in EBV + GC, and its expression was an independent predictor of overall survival (OS). EBV infection up-regulated CHAF1A expression which also predicted EBV infection well. CHAF1A expression also predicted microsatellite instability (MSI) and a high tumor mutation burden (TMB). The combined score (CS) of CHAF1A expression with MSI or TMB further improved prognostic stratification. CHAF1A IHC score positively correlated with the infiltration of NK cells and macrophages M1. CHAF1A expression alone could predict the immunotherapy response, but its CS with EBV infection, MSI, TMB, or PD-L1 expression showed better effects and improved response stratification based on current biomarkers.ConclusionsCHAF1A could be a novel biomarker for immunotherapy of GC, with the potential to improve the efficacy of existing biomarkers.

Enhanced Photodynamic Therapy Synergizing with Inhibition of Tumor Neutrophil Ferroptosis Boosts Anti-PD-1 Therapy of Gastric Cancer.

For tumor treatment, the ultimate goal in tumor therapy is to eliminate the primary tumor, manage potential metastases, and trigger an antitumor immune response, resulting in the complete clearance of all malignant cells. Tumor microenvironment (TME) refers to the local biological environment of solid tumors and has increasingly become an attractive target for cancer therapy. Neutrophils within TME of gastric cancer (GC) spontaneously undergo ferroptosis, and this process releases oxidized lipids that limit T cell activity. Enhanced photodynamic therapy (PDT) mediated by di-iodinated IR780 (Icy7) significantly increases the production of reactive oxygen species (ROS). Meanwhile, neutrophil ferroptosis can be triggered by increased ROS generation in the TME. In this study, a liposome encapsulating both ferroptosis inhibitor Liproxstatin-1 and modified photosensitizer Icy7, denoted LLI, significantly inhibits tumor growth of GC. LLI internalizes into MFC cells to generate ROS causing immunogenic cell death (ICD). Simultaneously, liposome-deliver Liproxstatin-1 effectively inhibits the ferroptosis of tumor neutrophils. LLI-based immunogenic PDT and neutrophil-targeting immunotherapy synergistically boost the anti-PD-1 treatment to elicit potent TME and systemic antitumor immune response with abscopal effects. In conclusion, LLI holds great potential for GC immunotherapy.

Gastric cancer immunotherapy: A scientometric and clinical trial review.

This letter is intended to arouse your interest in a recent review of comprehensive scientometrics and clinical trials on immunotherapy for gastric cancer (GC). Our study reviews recent advances in immunotherapy in the field of GC and highlights its new prospects as a treatment for GC. Our research reveals China's leadership in this field, as well as new therapeutic strategies such as immune checkpoint inhibitors, cellular immunotherapy, and vaccines. The combined findings highlight the potential of immunotherapy to improve survival and quality of life in patients with stomach cancer. We believe that this study will provide important guidance for the future direction of the GC treatment field.

The implication of integrative multiple RNA modification-based subtypes in gastric cancer immunotherapy and prognosis

Previous studies have focused on the impact of individual RNA modifications on tumor development. This study comprehensively investigated the effects of multiple RNA modifications, including m6A, alternative polyadenylation, pseudouridine, adenosine-to-inosine editing, and uridylation, on gastric cancer (GC). By analyzing 1,946 GC samples from eleven independent cohorts, we identified distinct clusters of RNA modification genes with varying survival rates and immunological characteristics. We assessed the chromatin activity of these RNA modification clusters through regulon enrichment analysis. A prognostic model was developed using Stepwise Regression and Random Survival Forest algorithms and validated in ten independent datasets. Notably, the low-risk group showed a more favorable prognosis and positive response to immune checkpoint blockade therapy. Single-cell RNA sequencing confirmed the abundant expression of signature genes in B cells and plasma cells. Overall, our findings shed light on the potential significance of multiple RNA modifications in GC prognosis, stemness development, and chemotherapy resistance.

[ARL67156, a small-molecule CD39 inhibitor, enhances natural killer cell cytotoxicity against gastric cancer cells in vitro and in nude mice].

To investigate the effect of ARL67156, a small-molecule inhibitor of CD39, on cytotoxicity of natural killer (NK) cells against gastric cancer cells. Human peripheral blood-derived primary NK cells isolated and purified using a magnetic bead antibody method were treated with 100 μmol/L ARL67156 for 24 h, and the signaling pathway of NK cell activation was detected by Western blotting. The level of interferon-γ (IFN-γ) in the supernatant of NK cells co-cultured with gastric cancer cells was detected using ELISA, and NK cell CD107a degranulation was measured with flow cytometry. The cytotoxicity of NK cells against co-cultured gastric cancer cells was evaluated using flow cytometry. In a nude mouse model bearing subcutaneous gastric cancer xenografts, the therapeutic effect of intravenous transfusion of NK cells and intraperitoneal injection of ARL67156 was assessed by measuring the changes in tumor volume. (25.97 ± 5.69) % of peripheral blood NK cells from healthy individuals positive for CD39 expression. Treatment with ARL67156 significantly upregulated the activation molecules including NKG2D, DAP10, CD57, and CD16 and reduced the expressions of the inhibitory receptors TIGIT and KIR, thereby promoting the secretion of IFN-γ and CD107a degranulation in NK cells (P < 0.05). In both the in vitro and in vivo experiments, ARL67156 significantly enhanced the cytotoxicity of NK cells against gastric cancer cells (P < 0.05). ARL67156 activates NK cells through the vav1-Syk signaling pathway to enhance their cytotoxicity against gastric cancer cells, which may serve as a new strategy for NK cell immunotherapy for gastric cancer.

Neoadjuvant chemotherapy is linked to an amended anti-tumorigenic microenvironment in gastric cancer

BackgroundNeoadjuvant chemotherapy (NAC) is a frequently intervention for patients with locally advanced gastric cancer (GC). Nevertheless, its impact on the tumor immune microenvironment remains unclear. MethodsWe used immunohistochemistry to identify T-cell subpopulations, tumor-associated neutrophils (TANs), and tumor-associated macrophages (TAMs) in the GC microenvironment (GCME) among paired samples (pre-chemotherapy and post-chemotherapy) from 48 NAC-treated patients. Multiplex immunofluorescence (mIF) was performed to assess immune biomarkers, including CK, CD4, CD8, FOXP3, PD1, PD-L1, CD163, CD86, myeloperoxidase and Arginase-1 in paired samples from 6 GC patients whose response to NAC were rigorously defined. ResultsNAC was intricately linked to enhanced CD8+:CD4+ ratio, reduced CD163+ M2-like macrophages, augmented CD86+ M1: CD163+ M2-like macrophage ratio, and diminished FOXP3+ regulatory T cells (T-regs) and TANs density. Based on mIF, PD1+CD8+T-cells, FOXP3+T-regs, PD-L1+ TANs, and CD163+ M2-like macrophages exhibited marked reduction and greater co-localization with tumor cells following NAC. The pre-NAC FOXP3+ T-regs and CD163+ M2-like macrophages content was substantially elevated in the response cohort, whereas, the post-NAC CD8+:CD4+ and CD86+ M1: CD163+ M2-like macrophage ratios were intricately linked to the tumor pathologic response. We observed greater CD163+ M2-like macrophages and tumor cells co-localization following NAC, which was correlated with tumor pathologic response. Lastly, multivariate analysis revealed that post-NAC CD8+:CD4+ and CD86+ M1: CD163+ M2-like macrophage ratios were stand-alone indicators of positive patient prognosis. ConclusionsNAC converts the GCME to an anti-tumorigenic state that is conducive to enhanced patient outcome. These finding can significantly benefit the future planning of highly efficacious and personalized GC immunotherapy.

Role of AT-rich interaction domain 1A in gastric cancer immunotherapy: Preclinical and clinical perspectives.

The application of immune checkpoint inhibitor (ICI) using monoclonal antibodies has brought about a profound transformation in the clinical outcomes for patients grappling with advanced gastric cancer (GC). Nonetheless, despite these achievements, the quest for effective functional biomarkers for ICI therapy remains constrained. Recent research endeavours have shed light on the critical involvement of modified epigenetic regulators in the pathogenesis of gastric tumorigenesis, thus providing a glimpse into potential biomarkers. Among these regulatory factors, AT-rich interaction domain 1A (ARID1A), a pivotal constituent of the switch/sucrose non-fermentable (SWI/SNF) complex, has emerged as a promising candidate. Investigations have unveiled the pivotal role of ARID1A in bridging the gap between genome instability and the reconfiguration of the tumour immune microenvironment, culminating in an enhanced response to ICI within the landscape of gastric cancer treatment. This all-encompassing review aims to dissect the potential of ARID1A as a valuable biomarker for immunotherapeutic approaches in gastric cancer, drawing from insights garnered from both preclinical experimentation and clinical observations.

TRIM29 promotes antitumor immunity through enhancing IGF2BP1 ubiquitination and subsequent PD-L1 downregulation in gastric cancer

Tripartite motif-containing protein 29 (TRIM29) is a member of TRIM family protein which has been reported to play a role in the progress of inflammatory and cancer diseases. However, its specific role in gastric cancer (GC) has yet to be fully understood. Here, we investigated the expression of TRIM29 in gastric cancer and its functions in the antitumor immunity. TRIM29 expression was lower in tumor tissues than that in paired normal tissues. Lower expression of TRIM29 was related to aberrant hypermethylation of CpG islands in TRIM29 gene. Comprehensive proteomics and immunoprecipitation analyses identified IGF2BP1 as TRIM29 interactors. TRIM29 interacted with IGF2BP1 and induced its ubiquitination at Lys440 and Lys450 site by K48-mediated linkage for protein degradation. IGF2BP1 promoted PD-L1 mRNA stability and expression in a 3′UTR and m6A-dependent manner. Functionally, TRIM29 enhanced antitumor T-cell immunity in gastric cancer dependent on the IGF2BP1/PD-L1 axis in vivo and in vitro. Clinical correlation analysis revealed that TRIM29 expression in patient samples was associated with CD8+ immune cell infiltration in the GC microenvironment and the overall survival rates of GC patients. Our findings revealed a crucial role of TRIM29 in regulating the antitumor T-cell immunity in GC. We also suggested that the TRIM29/IGF2BP1/PD-L1 axis could be used as a diagnostic and prognostic marker of gastric cancer and a promising target for GC immunotherapy.