Current status of immunotherapy for advanced gastric cancer

Surrogate endpoints in phase III randomized trials of advanced gastroesophageal cancer: A systematic review and meta-analysis

Overall survival (OS) is the most meaningful endpoint in clinical trials. However, owing to their limitations, surrogate endpoints are commonly used and validation studies are required to assess their reliability. Analysis of phase III randomized controlled trials (RCTs) of advanced gastroesophageal cancer (AGC) with > 100 patients, correlation coefficients (r), and determination coefficients (R²) between OS and surrogates were evaluated through meta-analyses. Progression-free survival (PFS), time to progression (TTP), and objective response rate (ORR) were examined to determine their correlations with OS. Analysis of 65 phase III RCTs (29,766 subjects) showed a moderate correlation between PFS/TTP and OS (r = 0.77, R² = 0.59), while ORR correlation was low (r = 0.56, R² = 0.31). Excluding immunotherapy trials improved the PFS/TTP and OS correlations (r = 0.83, R² = 0.70). These findings suggest the potential use of PFS/TTP in AGC phase III investigations, disregarding the use of ORR as a surrogate endpoint.

Geriatric nutritional risk index predicts the prognosis of gastric cancer patients treated with immune checkpoint inhibitors

The nutritional status is closely linked to the immune function of patients. Previous studies have demonstrated the utility of the Geriatric Nutritional Risk Index (GNRI) in assessing nutritional status. The aim of this study is to investigate the prognostic significance of GNRI in patients with gastric cancer who received immune checkpoint inhibitor (ICI) therapy. The study enrolled 89 gastric cancer patients who received different types of immune checkpoint inhibitors (ICIs) between August 2016 and December 2020, along with 57 patients who underwent chemotherapy during the same period as a control group. The GNRI cutoff point was established based on prior research. Differences in clinical and pathological features were analyzed using the Chi-square test or independent samples t-test. Univariate and multivariate analyses were used to identify prognostic factors for both progression-free survival (PFS) and overall survival (OS). Furthermore, nomograms were created to predict the likelihood of patient survival. There were 31 cases (21.2%) with GNRI < 92.00 and 115 cases (78.8%) with GNRI ≥ 92.00. Patients with low GNRI had significantly shorter PFS (21.33 months vs 28.37 months, P = .001) and OS (33.06 months vs 41.63 months, P = .001) than those with high GNRI, among all patients. Similar results were also found in patients treated with ICIs. Additionally, GNRI was identified as an independent prognostic factor. The C-index and 95% CI of the nomograms for predicting survival probabilities were 0.667 (0.600-0.735) and 0.685 (0.622-0.749), respectively. GNRI was significantly associated with survival time in patients with gastric cancer who received ICIs, patients with low GNRI had shorter PFS and OS. GNRI might be able to identify patients who might benefit from ICIs.

Safety and clinical efficacy of immune checkpoint inhibitors in advanced gastric cancer in the real world

BACKGROUND

To evaluate the clinical efficacy and safety of immune checkpoint inhibitors in patients with advanced gastric cancer in the real world.

METHODS

The retrospective analysis was conducted on the clinical records of 402 patients with advanced gastric cancer who were admitted to the Nanjing Drum Tower Hospital between December 2017 and April 2022 and who had received immunotherapy. Observation target: drug use, treatment, adverse reaction type and grade, objective response rate (ORR), disease control rate (DCR), progression free survival (PFS), and overall survival (OS).

RESULTS

By retrospectively analyzing the data of patients with advanced gastric cancer treated with ICIs previously admitted to our medical center, we found some clinical characteristic factors associated with the occurrence of irAEs as well as the efficacy and prognosis: the presence or absence of hypertension, whether or not to receive targeted therapies can predict the occurrence of immune-related adverse events (irAEs), and the more the presence of irAEs, the better the prognosis. These can help clinicians in clinical drug selection.

CONCLUSIONS

The results of this paper show that the occurrence of irAEs is associated with patients' OS. irAEs occurrence can prolong patients' OS. irAEs occurrence may serve as a surrogate marker for ICIs.

Metabolic and immune-related gene signatures: Predictive stratification and prognostic implications in gastric cancer

BACKGROUND

Gastric cancer, marked by its heterogeneous nature, showcases various molecular subtypes and clinical trajectories. This research delves into the significance of metabolic and immune-driven pathways in gastric cancer, constructing a prognostic signature derived from differentially expressed metabolic and immune-correlated genes (DE-MIGs).

METHODS

Metabolic and immune-associated gene were sourced from the GeneCards database. Differential expression analysis on the TCGA-STAD dataset was executed using the limma package, unveiling 51 DE-MIGs that underwent functional enrichment scrutiny. The LASSO Cox regression methodology guided the creation of the prognostic signature, and individual patient risk scores were determined. Assessment tools like CIBERSORT, ESTIMATE and ssGSEA were deployed to study the immune microenvironment, while mutation profiles, genomic stability, resistance to chemotherapy and immunotherapy responsiveness were scrutinized across distinct signature categorizations.

RESULTS

Among the identified DE-MIGs, 26 were significantly tied to the overall survival of gastric cancer patients. The developed prognostic signature proficiently differentiated patients into high-risk and low-risk cohorts, with the latter showing markedly better outcomes. The study underscored the centrality of the immune microenvironment in influencing gastric cancer outcomes. Key pathways such as TGF-Beta, TP53 and NRF2 dominated the high-risk group, whereas the LRTK-RAS and WNT pathways characterized the low-risk group. Interestingly, the low-risk segment also manifested a heightened tumor mutation burden and enhanced susceptibility to immunotherapy.

CONCLUSIONS

Our findings introduce a pivotal prognostic signature, rooted in DE-MIGs, that effectively segregates gastric cancer patients into distinct risk-based segments. Insights into the influential role of the immune microenvironment in gastric cancer progression pave the way for more refined therapeutic interventions.

MTF1 has the potential as a diagnostic and prognostic marker for gastric cancer and is associated with good prognosis

PURPOSE

Metal Regulatory Transcription Factor 1 (MTF1) can be an essential transcription factor for heavy metal response in cells and can also reduce oxidative and hypoxic stresses in cells. However, the current research on MTF1 in gastric cancer is lacking.

METHODS

Bioinformatics techniques were used to perform expression analysis, prognostic analysis, enrichment analysis, tumor microenvironment correlation analysis, immunotherapy Immune cell Proportion Score (IPS) correlation and drug sensitivity correlation analysis of MTF1 in gastric cancer. And qRT-PCR was used to verify MTF1 expression in gastric cancer cells and tissues.

RESULTS

MTF1 showed low expression in gastric cancer cells and tissues, and low expression in T3 stage compared with T1 stage. KM prognostic analysis showed that high expression of MTF1 was significantly associated with longer overall survival (OS), FP (first progression) and PPS (post-progression survival) in gastric cancer patients. Cox regression analysis showed that MTF1 was an independent prognostic factor and a protective factor in gastric cancer patients. MTF1 is involved in pathways in cancer, and the high expression of MTF1 is negatively correlated with the half maximal inhibitory concentration (IC50) of common chemotherapeutic drugs.

CONCLUSION

MTF1 is relatively lowly expressed in gastric cancer. MTF1 is also an independent prognostic factor for gastric cancer patients and is associated with good prognosis. It has the potential to be a diagnostic and prognostic marker for gastric cancer.

Immunotherapy Efficacy-related Risk Classifier Differentiate Prognostic Characteristics of Gastric Cancer-A Large-scale Retrospective Study

Prognostic signatures related to the efficacy of immunotherapy have not been determined in gastric cancer (GC). We identified the differentially expressed genes between the CR/PR and SD/PD groups with the R package "limma" (false discovery rate <0.05) in the IMvigor210 data set. The GSE13861 (n=65), GSE15459 (n=192), GSE26899 (n=93), GSE26901 (n=109), GSE28541 (n=40), GSE34942 (n=56), and GSE62254 (n=300) cohorts were merged into a training cohort (n=855). Univariate Cox regression analysis, LASSO penalized Cox regression analysis, and multivariate Cox regression analysis were jointly applied to construct the prognostic model. The Cancer Genome Atlas (TCGA)-STAD (n=371), GSE84437 (n=433), GSE26253 (n=432), and IMvigor210 (n=348) cohorts were utilized for external validation. The GC patients were divided into 16 subgroups according to clinical features for universal applicability validation. Repeated validation confirmed that the overall survival of the high-risk (HR) group was significantly reduced compared with that of the low-risk (LR) group. The HR group showed a higher infiltration abundance of regulatory T cells, macrophages, T follicular helper cells, and natural killer T cells, whereas the infiltration levels of activated CD4 T cells and monocytes were upregulated in the LR group. The calcium, TGF-β, MAPK, Hedgehog, and KRAS signaling pathways were overactivated in the HR group, while the hallmarks related to DNA damage repair and metabolism were enriched in the LR group. In addition, the LR group had high tumor mutation burden, FLG, and OBSCN mutations. A prognostic risk classifier for GC patients was identified and validated by carrying out a multicenter retrospective study.

Evaluation of ITGB1 expression as a predictor of the therapeutic effects of immune checkpoint inhibitors in gastric cancer

BACKGROUND

Gastric cancer (CC) is a disease with high incidence and mortality rate. Immunotherapy is an important method for gastric cancer while lack of effective predictor. Integrins play an important role in the development. We aimed to explore the predictive value of β1 integrin (ITGB1) as a predictor of immunnotherapy in gastric cancer.

METHODS

Differential expression analysis was conducted using the Gene Expression Profiling Interactive Analysis (GEPIA) 2.0 and GEO databases. GEPIA data were used to evaluate the prognostic value of ITGB1 in gastric cancer (GC). Transcriptomic and clinical data of GC and normal tissues were downloaded from The Cancer Genome Atlas database, and the TIMER database was used to evaluate the association between ITGB1 and immune infiltration. Time-dependent receiver operating characteristic (ROC) curve analysis was used to determine the prognostic value of ITGB1. To verify ITGB1 expression at the protein level, immunohistochemical staining was conducted. In addition, to analyze the correlation of ITGB1 with PD-1 and PD-L1, we examined levels of PD-1 and PD-L1 by IHC and determined the predictive value of ITGB1 for anti-PD-1 therapy in GC by ROC curve analysis.

RESULTS

Compared with normal tissues, analysis of GEPIA and data at protein levels showed significantly higher expression of ITGB1 in GC. In addition, higher expression of ITGB1 was associated with worse pathological G-staging and tumor T-staging, which suggested that ITGB1 is a risk factor for poor prognosis in GC. The level of ITGB1 expression was positively correlated with CD8 + T cells, neutrophils, macrophages, and dendritic cells. ITGB1 expression was also correlated with PD-L1 expression, and this was further verified at the protein level by immunohistochemical analysis. The area under the ROC curve was 0.808.

CONCLUSION

ITGB1 may be a promising prognostic biomarker and effective predictor for anti-PD-1 therapy in GC.

TRIAL REGISTRATION

Retrospectively registered.

Integrative analysis of cancer-associated fibroblast signature in gastric cancer

Background

CAFs regulate the signaling of GC cells by promoting their migration, invasion, and proliferation and the function of immune cells as well as their location and migration in the TME by remodeling the extracellular matrix (ECM). This study explored the understanding of the heterogeneity of CAFs in TME and laid the groundwork for GC biomarker and precision treatment development.

Methods

The scRNA-seq and bulk RNA-seq datasets were obtained from GEO and TCGA. The prognostic significance of various CAFs subtypes was investigated using ssGSEA combined with Kaplan-Meier analysis. POSTN expression in GC tissues and CAFs was detected using immunohistochemistry, immunofluorescence, and Western blotting. Differential expression analysis identified the differentially expressed genes (DEGs) between normal and tumor samples in TCGA-STAD. Pearson correlation analysis identified DEGs associated with adverse prognosis CAF subtype, and univariate Cox regression analysis determined prognostic genes associated with CAFs. LASSO regression analysis and Multivariate Cox regression were used to build a prognosis model for CAFs.

Results

We identified five CAFs subtypes in GC, with the CAF_0 subtype associated with poor prognosis. The abundance of CAF_0 correlated with T stage, clinical stage, histological type, and immune cell infiltration levels. Periostin (POSTN) exhibited increased expression in both GC tissues and CAFs and was linked to poor prognosis in GC patients. Through LASSO and multivariate Cox regression analysis, three genes (CXCR4, MATN3, and KIF24) were selected to create the CAFs-score. We developed a nomogram to facilitate the clinical application of the CAFs-score. Notably, the CAFs signature showed significant correlations with immune cells, stromal components, and immunological scores, suggesting its pivotal role in the tumor microenvironment (TME). Furthermore, CAFs-score demonstrated prognostic value in assessing immunotherapy outcomes, highlighting its potential as a valuable biomarker to guide therapeutic decisions.

Conclusion

CAF_0 subtype in TME is the cause of poor prognosis in GC patients. Furthermore, CAFs-score constructed from the CAF_0 subtype can be used to determine the clinical prognosis, immune infiltration, clinicopathological characteristics, and assessment of personalized treatment of GC patients.

Prognosis signature for predicting the survival and immunotherapy response in esophageal carcinoma based on cellular senescence-related genes

Background

Cellular senescence occurs throughout life and can play beneficial roles in a variety of physiological processes, including embryonic development, tissue repair, and tumor suppression. However, the relationship between cellular senescence-related genes (CSRGs) and immunotherapy in esophageal carcinoma (ECa) remains poorly defined.

Methods

The data set used in the analysis was retrieved from TCGA (Research Resource Identifier (RRID): SCR_003193), GEO (RRID: SCR_005012), and CellAge databases. Data processing, statistical analysis, and diagram formation were conducted in R software (RRID: SCR_001905) and GraphPad Prism (RRID: SCR_002798). Based on CSRGs, we used the TCGA database to construct a prognostic signature for ECa and then validated it in the GEO database. The predictive efficiency of the signature was evaluated using receiver operating characteristic (ROC) curves, Cox regression analysis, nomogram, and calibration curves. According to the median risk score derived from CSRGs, patients with ECa were divided into high- and low-risk groups. Immune infiltration and immunotherapy were also analyzed between the two risk groups. Finally, the hub genes of the differences between the two risk groups were identified by the STRING (RRID: SCR_005223) database and Cytoscape (RRID: SCR_003032) software.

Results

A six-gene risk signature (DEK, RUNX1, SMARCA4, SREBF1, TERT, and TOP1) was constructed in the TCGA database. Patients in the high-risk group had a worse overall survival (OS) was disclosed by survival analysis. As expected, the signature presented equally prognostic significance in the GSE53624 cohort. Next, the Area Under ROC Curve (AUC=0.854) and multivariate Cox regression analysis (HR=3.381, 2.073-5.514, P<0.001) also proved that the risk signature has a high predictive ability. Furthermore, we can more accurately predict the prognosis of patients with ECa by nomogram constructed by risk score. The result of the TIDE algorithm showed that ECa patients in the high-risk group had a greater possibility of immune escape. At last, a total of ten hub genes (APOA1, MUC5AC, GC, APOA4, AMBP, FABP1, APOA2, SOX2, MUC8, MUC17) between two risk groups with the highest interaction degrees were identified. By further analysis, four hub genes (APOA4, AMBP, FABP1, and APOA2) were related to the survival differences of ECa.

Conclusions

Our study reveals comprehensive clues that a novel signature based on CSRGs may provide reliable prognosis prediction and insight into new therapy for patients with ECa.

Prognostic value of neutrophil-to-lymphocyte ratio in gastric cancer patients treated with immune checkpoint inhibitors: A meta-analysis

The neutrophil-to-lymphocyte ratio (NLR) has been extensively studied in patients with gastric cancer (GC) treated with immune checkpoint inhibitors (ICIs), although the results are controversial. Therefore, we performed the present meta-analysis to systematically assess the correlation between NLR and prognosis and clinicopathological factors in GC patients undergoing treatment with ICIs. Among the electronic databases, PubMed, Web of Science, Embase, and Cochrane Library were thoroughly searched. To estimate the prognostic value of NLR for progression-free survival (PFS) and overall survival (OS), hazard ratios (HRs) were calculated, and their 95% confidence intervals were calculated. This meta-analysis included 10 studies with 830 patients. Based on the pooled data, a high NLR was associated with poor OS in GC patients receiving ICIs (HR = 2.13, 95% confidence interval [CI] = 1.70-2.66, p < 0.001). Elevated NLR was a significant biomarker for worse PFS in GC patients treated with ICIs (HR = 1.74, 95% CI = 1.22-2.48, p = 0.002). There was, however, no significant correlation between NLR and sex, age, and Eastern Cooperative Oncology Group Performance Status (PS) of the ECOG, differentiation, human epidermal growth factor receptor 2 (HER2) status, or PD-L1 status in GC patients treated with ICIs. High NLR before treatment was associated with poor OS and PFS in GC patients treated with ICIs, according to our meta-analysis. NLR is an effective biomarker for evaluating the prognosis of GC patients receiving ICIs and provide more valuable information for treatment decisions in the era of immunotherapy for GC.

Efficacy of the low dose apatinib plus deep hyperthermia as third-line or later treatment in HER-2 negative advanced gastric cancer

Aim: To observe the efficacy of the low dose apatinib plus deep hyperthermia as third-line or later treatment for patients with human epidermal growth factor receptor 2 (HER-2) negative advanced gastric cancer. Methods: 80 eligible patients with HER-2 negative advanced gastric cancer admitted to Jingjiang People's Hospital Affiliated with Yangzhou University-from March 2021 to March 2022 were selected, and they were divided into the control group (n = 40, apatinib) and experimental group (n = 40, apatinib plus deep hyperthermia) on the basis of random number table method. The levels of serum carcinoembryonic antigen (CEA), carbohydrate antigen 199 (CA199), and vascular endothelial growth factor (VEGF) were monitored, and the efficacy of the two groups was analyzed by referring to Karnofsky performance status (KPS), overall survival (OS) and disease control rate (DCR) before and after treatment. Results: The levels of CEA, CA199, and VEGF in both groups were lower after treatment than before (p < 0.05), and lower (CEA: 8.85 ± 1.36 vs. 12.87 ± 1.23, CA199: 34.19 ± 4.68 vs. 50.11 ± 5.73, VEGF: 124.8 ± 18.03 vs. 205.9 ± 19.91) in the experimental group than in the control group (p < 0.05). The DCR and KPS of the patients in the experimental group were significantly higher (DCR: 62.50% vs. 40.00%; KPS: 83.25 ± 1.15 vs. 76.25 ± 1.17) than in the control group (p < 0.05). In survival analysis, patients with control group had shorter OS than the experimental group. (median 5.65 vs. 6.50 months; hazard ratio [HR], 1.63 [95% confidence interval (CI) 1.02-2.60], p = 0.0396). Conclusion: The application of low-dose apatinib plus deep hyperthermia for patients with HER-2 negative gastric cancer who failed second-line treatment should be a promising option.

Exosome-mediated miR-200a delivery into TGF-β-treated AGS cells abolished epithelial-mesenchymal transition with normalization of ZEB1, vimentin and Snail1 expression

Exosomes are small extracellular vesicles that can be derived from human cells such as mesenchymal stem cells (MSCs). The size of exosomes is at nano-scale range and owing to their biocompatibility and other characteristics, they have been promising candidates for delivery of bioactive compounds and genetic materials in disease therapy, especially cancer therapy. Gastric cancer (GC) is a leading cause of death among patients and this malignant disease affects gastrointestinal tract that its invasiveness and abnormal migration mediate poor prognosis of patients. Metastasis is an increasing challenge in GC and microRNAs (miRNAs) are potential regulators of metastasis and related molecular pathways, especially epithelial-to-mesenchymal transition (EMT). In the present study, our aim was to explore role of exosomes in miRNA-200a delivery for suppressing EMT-mediated GC metastasis. Exosomes were isolated from MSCs via size exclusion chromatography. The synthetic miRNA-200a mimics were transfected into exosomes via electroporation. AGS cell line exposed to TGF-β for EMT induction and then, these cells cultured with miRNA-200a-loaded exosomes. The transwell assays performed to evaluate GC migration and expression levels of ZEB1, Snail1 and vimentin measured. Exosomes demonstrated loading efficiency of 5.92 ± 4.6%. The TGF-β treatment transformed AGS cells into fibroblast-like cells expressing two stemness markers, CD44 (45.28%) and CD133 (50.79%) and stimulated EMT. Exosomes induced a 14.89-fold increase in miRNA-200a expression in AGS cells. Mechanistically, miRNA-200a enhances E-cadherin levels (P < 0.01), while it decreases expression levels of β-catenin (P < 0.05), vimentin (P < 0.01), ZEB1 (P < 0.0001) and Snail1 (P < 0.01). Leading to EMT inhibition in GC cells. This pre-clinical experiment introduces a new strategy for miRNA-200a delivery that is of importance for preventing migration and invasion of GC cells.

The tissue-resident marker CD103 on peripheral blood T cells predicts responses to anti-PD-1 therapy in gastric cancer

BACKGROUND

Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment. Since clinical benefits are limited to a subset of patients, we aimed to identify peripheral blood biomarkers that predict the efficacy of the anti-programmed cell death protein 1 (PD-1) antibody (nivolumab) in patients with gastric cancer.

METHODS

We collected peripheral blood samples from gastric cancer patients (n = 29) before and after treatment with nivolumab and investigated the relationship between the frequency of surface or intracellular markers among nivolumab-binding PD-1⁺CD8⁺ T cells and treatment responses using multicolor flow cytometry. The tumors, lymph nodes, and peripheral blood of gastric cancer patients who underwent gastrectomy following nivolumab treatment were collected, and nivolumab-binding PD-1⁺CD8⁺ T cells in these tissue samples were characterized.

RESULTS

Patients with a high frequency of CD103 among PD-1⁺CD8⁺ T cells in peripheral blood 2 weeks after the start of treatment had significantly better progression-free survival than the low group (P = 0.032). This CD103⁺PD-1⁺CD8⁺ T cell population mainly consisted of central memory T cells, showing the high expression of Ki-67 and few cytotoxic granules. In contrast, effector memory T cells were more frequently observed among CD103⁺PD-1⁺CD8⁺ T cells in tumors, which implied a change in the differentiated status of central memory T cells in lymph nodes and peripheral blood to effector memory T cells in tumors during the treatment with ICIs.

CONCLUSIONS

A high frequency of CD103 among PD-1⁺CD8⁺ T cells 2 weeks after nivolumab treatment in patients with advanced gastric cancer may be a useful biomarker for predicting the efficacy of anti-PD-1 therapy.

Prognostic significances of PD-L1- and CTLA-4-positive T cells and positive correlations of immunosuppressive marker expression between cancer tissue and peripheral blood in patients with gastric cancer

Introduction

Although tumor, node, metastasis (TNM) staging has been used for prognostic assessment of gastric cancer (GC), the prognosis may vary among patients with the same TNM stage. Recently, the TNM-Immune (TNM-I) classification staging system has been used for prognostic assessment of colorectal cancer based on intra-tumor T-cell status, which is a superior prognostic factor compared with the American Joint Committee on Cancer staging manual. However, an immunoscoring system with prognostic significance for GC has not been established.

Method

Here, we evaluated immune phenotypes in cancer and normal tissues, then examined correlations between tissues and peripheral blood. GC patients who underwent gastrectomy at Seoul St. Mary's Hospital between February 2000 and May 2021 were included. We collected 43 peripheral blood samples preoperatively and a pair of gastric mucosal samples postoperatively, including normal and cancer mucosa, which did not influence tumor diagnosis and staging. Tissue microarray samples of GC were collected from 136 patients during surgery. We investigated correlations of immune phenotypes between tissues and peripheral blood using immunofluorescence imaging and flow cytometry, respectively. GC mucosa exhibited an increased number of CD4⁺ T cells, as well as increased expression levels of immunosuppressive markers (e.g., programmed death-ligand-1 [PD-L1], cytotoxic T lymphocyte antigen-4 [CTLA-4], and interleukin-10), in CD4+ T cells and non-T cells.

Result

The expression levels of immunosuppressive markers were significantly increased in cancer tissues and peripheral blood mononuclear cells. In gastric mucosal tissues and peripheral blood of GC patients, similar immunosuppression phenotypes were observed, including increased numbers of PD-L1- and CTLA-4-positive T cells.

Discussion

Therefore, peripheral blood analysis may be an important tool for prognostic assessment of GC patients.

TRIM44 regulates tumor immunity in gastric cancer through LOXL2-dependent extracellular matrix remodeling

PURPOSE

Gastric cancer is a gastrointestinal malignancy with high mortality and poor prognosis, and the molecular mechanism of gastric tumorigenesis remains unclear. TRIM44 has been reported to be involved in tumor development. However, the role of TRIM44 in tumor immunity is largely unknown.

METHODS

We analyzed TRIM44 expression in clinical gastric cancer tissues and normal tissues by using western blot, quantitative real-time PCR and bioinformatics analyses. We further investigated the involvement of TRIM44 in tumor immunity in vivo and found that it was dependent on extracellular matrix remodeling. We detected the interaction between TRIM44 and LOXL2 by using immunofluorescence staining and coimmunoprecipitation assays. We observed that TRIM44 mediates the stability of LOXL2 by ubiquitination assays.

RESULTS

TRIM44 expression is high and is correlated with T-cell infiltration in gastric cancer. TRIM44 inhibits gastric tumorigenicity by regulating T-cell-mediated antitumor immunity and modulating the protein level of LOXL2. Mechanistically, TRIM44 directly binds to LOXL2 and affects the stability of LOXL2 to change extracellular matrix remodeling and influence tumor immunity.

CONCLUSION

These findings demonstrate that TRIM44 regulates the stability of LOXL2 to remodel the tumor extracellular matrix to modulate tumor immunity in gastric cancer and that the TRIM44/LOXL2 complex is a promising biomarker for gastric cancer prognosis and might be a novel immunotherapy target.

Radiomics-based prediction of response to immune checkpoint inhibitor treatment for solid cancers using computed tomography: a real-world study of two centers

BACKGROUND

Immune checkpoint inhibitors (ICIs) represent an approved treatment for various cancers; however, only a small proportion of the population is responsive to such treatment. We aimed to develop and validate a plain CT-based tool for predicting the response to ICI treatment among cancer patients.

METHODS

Data for patients with solid cancers treated with ICIs at two centers from October 2019 to October 2021 were randomly divided into training and validation sets. Radiomic features were extracted from pretreatment CT images of the tumor of interest. After feature selection, a radiomics signature was constructed based on the least absolute shrinkage and selection operator regression model, and the signature and clinical factors were incorporated into a radiomics nomogram. Model performance was evaluated using the training and validation sets. The Kaplan-Meier method was used to visualize associations with survival.

RESULTS

Data for 122 and 30 patients were included in the training and validation sets, respectively. Both the radiomics signature (radscore) and nomogram exhibited good discrimination of response status, with areas under the curve (AUC) of 0.790 and 0.814 for the training set and 0.831 and 0.847 for the validation set, respectively. The calibration evaluation indicated goodness-of-fit for both models, while the decision curves indicated that clinical application was favorable. Both models were associated with the overall survival of patients in the validation set.

CONCLUSIONS

We developed a radiomics model for early prediction of the response to ICI treatment. This model may aid in identifying the patients most likely to benefit from immunotherapy.

Recent Trends and Advancements in the Diagnosis and Management of Gastric Cancer

Gastric cancer is an enigmatic malignancy that has recently been shown to be increasing in incidence globally. There has been recent progress in emerging technologies for the diagnosis and treatment of the disease. Improvements in non-invasive diagnostic techniques with serological tests and biomarkers have led to decreased use of invasive procedures such as endoscopy. A multidisciplinary approach is used to treat gastric cancer, with recent significant advancements in systemic therapies used in combination with cytotoxic chemotherapies. New therapeutic targets have been identified and clinical trials are taking place to assess their efficacy and safety. In this review, we provide an overview of the current and emerging treatment strategies and diagnostic techniques for gastric cancer.

Prognosis and tumor immune microenvironment of patients with gastric cancer by a novel senescence-related signature

BACKGROUND

Cellular senescence is a stable state of cell cycle arrest that plays a crucial role in the tumor microenvironment (TME) and cancer progression. Nevertheless, the accurate prognosis of gastric cancer (GC) is complicated to predict due to tumor heterogeneity. The work aimed to build a novel prognostic model in GC.

METHODS

LASSO and Cox regression analysis were constructed to develop a prognostic senescence-related signature. The Gene Expression Omnibus dataset was used for external validation of signature. Afterward, we performed correlation analysis for the risk score and the infiltrating abundance of immune cells, TME scores, drug response, tumor mutational burden (TMB), and immunotherapy efficacy.

RESULTS

Five senescence-related genes (AKR1B1, CTNNAL1, DUSP16, PLA2R1, and ZFP36) were screened to build a signature. The high-risk group had a shorter overall survival, cancer-specific survival, and progression-free survival when compared to the low-risk group. We further constructed a nomogram based on risk score and clinical traits, which can predict the prognosis of GC patients more accurately. Moreover, the risk score was evidently correlated with infiltration of immune cells, TME score, TMB, TIDE score, and chemotherapy sensitivity. Meanwhile, the Kyoto Encyclopedia of Genes and Genomes pathway showed that the PI3K-Akt and Wnt signaling pathway were differentially enriched in the high-risk group.

CONCLUSIONS

The senescence-related signature was an accurate tool to guide the prognosis and might promote the progress of personalized treatment.

Integrated Analyses of m6A Regulator-Based Signature on Its Clinical Application and Immunogenomic Landscape in Stomach Adenocarcinoma

Background. The whole tumor microenvironment (TME) infiltration features monitored by integrated roles of different RNA N6-methyladenosine (m6A) regulators remain elusive. Our study is aimed at exploring the association between m6A modification patterns, TME cell-infiltrating levels, and patients’ prognosis in stomach adenocarcinoma (STAD) patients. Methods. Consensus clustering was performed based on the integrated analyses of 17 m6A regulators and 229 m6A-related hallmark genes in STAD (The Cancer Genome Atlas (TCGA) cohort, $n=443$ ; Gene Expression Omnibus (GEO) GSE57303, $n=70$ , GSE62254 $n=300$ , and GSE84437 $n=433$ ). A m6ASig scoring system was calculated by the principal component analysis (PCA), and its prognostic value was validated in an independent dataset GES15459. Results. Three m6A clusters were identified among 1246 STAD patients, which had significant overall survival (OS) differences and demonstrated different TME immune cell infiltration and biological behaviors. According to the m6ASig score, which was generated from the m6A-related hallmark genes, STAD patients were divided into the high-m6ASig group ( $n=585$ ) and low-m6ASig group ( $n=586$ ). Patients in the high-m6ASig group had a notably prolonged OS and higher immune cell infiltration. Moreover, patients with higher m6ASig score were associated with higher microsatellite instability (MSI); higher PD-L1, CTLA4, and ERBB2 expressions; and greater tumor mutation burden (TMB). Patients with higher m6ASig score demonstrated a better immune response and drug sensitivity. Conclusion. Our m6ASig scoring system could characterize TME immune cell infiltration, thus predict patient’s prognosis and immunotherapy and chemotherapy efficacy, offering a novel tool for the individualized therapeutic implications for STAD patients.

Establishment of a Novel Prognostic Prediction Model for Gastric Cancer Based on Necroptosis-Related Genes

Background: Necroptosis plays a crucial role in the progression of multiple types of cancer. However, the role of necroptosis in gastric cancer (GC) remains unclear. The aim of this study is to establish a necroptosis-related prediction model, which could provide information for treatment monitoring.

Methods: The TCGA-STAD cohort was employed to establish a prognostic prediction signature and the GEO dataset was employed for external validation. The correlation between the risk score and the immune landscape, tumor mutational burden (TMB), microsatellite instability (MSI), as well as therapeutic responses of different therapies were analyzed.

Results: We constructed a prognostic model based on necroptosis-associated genes (NAGs), and its favorable predictive ability was confirmed in an external cohort. The risk score was confirmed as an independent determinant, and a nomogram was further established for prognosis. A high score implies higher tumor immune microenvironment (TIME) scores and more significant TIME cell infiltration. High-risk patients presented with lower TMB, and low-TMB patients had worse overall survival (OS). Meanwhile, Low-risk scores are characterized by MSI-high (MSI-H), lower Tumor Immune Dysfunction and Exclusion (TIDE) score, and higher immunogenicity in immunophenoscore (IPS) analysis.

Conclusion: The developed NAG score provides a novel and effective method for predicting the outcome of GC as well as potential targets for further research.

Consensus Molecular Subtypes Efficiently Classify Gastric Adenocarcinomas and Predict the Response to Anti-PD-1 Immunotherapy

Background: Gastric adenocarcinoma (GAC) is highly heterogeneous and closely related to colorectal cancer (CRC) both molecularly and functionally. GAC is currently subtyped using a system developed by TCGA. However, with the emergence of immunotherapies, this system has failed to identify suitable treatment candidates. Methods: Consensus molecular subtypes (CMSs) developed for CRC were used for molecular subtyping in GAC based on public expression cohorts, including TCGA, ACRG, and a cohort of GAC patients treated with the programmed cell death 1 (PD-1) inhibitor pembrolizumab. All aspects of each subtype, including clinical outcome, molecular characteristics, oncogenic pathway activity, and the response to immunotherapy, were fully explored. Results: CMS classification was efficiently applied to GAC. CMS4, characterized by EMT activation, stromal invasion, angiogenesis, and the worst clinical outcomes (median OS 24.2 months), was the predominant subtype (38.8%~44.3%) and an independent prognostic indicator that outperformed classical TCGA subtyping. CMS1 (20.9%~21.5%) displayed hypermutation, low SCNV, immune activation, and best clinical outcomes (median OS > 120 months). CMS3 (17.95%~25.7%) was characterized by overactive metabolism, KRAS mutation, and intermediate outcomes (median OS 85.6 months). CMS2 (14.6%~16.3%) was enriched for WNT and MYC activation, differentiated epithelial characteristics, APC mutation, lack of ARID1A, and intermediate outcomes (median OS 48.7 months). Notably, CMS1 was strongly correlated with immunotherapy biomarkers and favorable for the anti-PD-1 drug pembrolizumab, whereas CMS4 was poorly responsive but became more sensitive after EMT-based stratification. Conclusions: Our study reveals the practical utility of CMS classification for GAC to improve clinical outcomes and identify candidates who will respond to immunotherapy.

Effects of helicobacter pylori on tumor microenvironment and immunotherapy responses

Helicobacter pylori is closely associated with gastric cancer. During persistent infection, Helicobacter pylori can form a microenvironment in gastric mucosa which facilitates the survival and colony formation of Helicobacter pylori. Tumor stromal cells are involved in this process, including tumor-associated macrophages, mesenchymal stem cells, cancer-associated fibroblasts, and myeloid-derived suppressor cells, and so on. The immune checkpoints are also regulated by Helicobacter pylori infection. Helicobacter pylori virulence factors can also act as immunogens or adjuvants to elicit or enhance immune responses, indicating their potential applications in vaccine development and tumor immunotherapy. This review highlights the effects of Helicobacter pylori on the immune microenvironment and its potential roles in tumor immunotherapy responses.

The Prognostic Value of Gastric Immune Prognostic Index in Gastric Cancer Patients Treated With PD-1/PD-L1 Inhibitors

Objective: This study aimed to investigate the prognostic value of the gastric immune prognostic index (GIPI) in gastric cancer patients treated with programmed death 1/programmed death-ligand 1 (PD-1/PD-L1) inhibitors.

Methods: This study was conducted to elucidate the role of GIPI using the data from 146 gastric cancer patients treated with PD-1/PD-L1 inhibitors between August 2016 and December 2020 in Harbin Medical University Cancer Hospital. The GIPI calculation was based on dNLR and LDH. Patients were categorized into three groups: 1) GIPI good (LDH ≤250 U/L and dNLR ≤3); 2) GIPI intermediate (LDH &gt;250 U/L and NLR &gt;3); 3) GIPI poor (LDH &gt;250 U/L and dNLR &gt;3). The correlations between GIPI and clinicopathologic characteristics were determined by the Chi-square test or the Fisher’s exact test. The Kaplan–Meier analysis and log-rank test were used to calculate and compare progression-free survival (PFS) and overall survival (OS). The univariate and multivariate Cox proportional hazards regression model was used to detect prognostic and predictive factors of PFS and OS.

Results: 146 patients treated with PD-1/PD-L1 inhibitors were included in this study, of which, 72.6% were GIPI good, 23.3% were GIPI intermediate, and 4.1% were GIPI poor. The GIPI was associated with the common blood parameters, including neutrophils and lymphocytes. The multivariate analysis showed that platelet, TNM stage, and treatment were the independent prognostic factors for PFS and OS. Patients with GIPI intermediate/poor were associated with shorter PFS (median: 24.63 vs. 32.50 months; p = 0.078) and OS (median: 28.37 months vs. not reached; p = 0.033) than those with GIPI good. GIPI intermediate/poor was correlated with shorter PFS and OS than GIPI good, especially in subgroups of patients with ICI treatment and patients with PD-1/PD-L1 positive status.

Conclusions: The GIPI correlated with poor outcomes for PD-1/PD-L1 expression status and may be useful for identifying gastric cancer patients who are unlikely to benefit from treatment.

Immunotherapy as a Therapeutic Strategy for Gastrointestinal Cancer-Current Treatment Options and Future Perspectives

Gastrointestinal (GI) cancer constitutes a highly lethal entity among malignancies in the last decades and is still a major challenge for cancer therapeutic options. Despite the current combinational treatment strategies, including chemotherapy, surgery, radiotherapy, and targeted therapies, the survival rates remain notably low for patients with advanced disease. A better knowledge of the molecular mechanisms that influence tumor progression and the development of optimal therapeutic strategies for GI malignancies are urgently needed. Currently, the development and the assessment of the efficacy of immunotherapeutic agents in GI cancer are in the spotlight of several clinical trials. Thus, several new modalities and combinational treatments with other anti-neoplastic agents have been identified and evaluated for their efficiency in cancer management, including immune checkpoint inhibitors, adoptive cell transfer, chimeric antigen receptor (CAR)-T cell therapy, cancer vaccines, and/or combinations thereof. Understanding the interrelation among the tumor microenvironment, cancer progression, and immune resistance is pivotal for the optimal therapeutic management of all gastrointestinal solid tumors. This review will shed light on the recent advances and future directions of immunotherapy for malignant tumors of the GI system.

Cellular Senescence-Related Genes: Predicting Prognosis in Gastric Cancer

Our study aimed to explore the effect of cellular senescence and to find potential therapeutic strategies for gastric cancer. Cellular senescence-related genes were acquired from the CellAge database, while gastric cancer data were obtained from GEO and TCGA databases. SMARCA4 had the highest mutation frequency (6%), and it was linked to higher overall survival (OS) and progression-free survival (PFS). The gastric cancer data in TCGA database served as a training set to construct a prognostic risk score signature, and GEO data were used as a testing set to validate the accuracy of the signature. Patients with the low-risk score group had a longer survival time, while the high-risk score group is the opposite. Patients with low-risk scores had higher immune infiltration and active immune-related pathways. The results of drug sensitivity analysis and the TIDE algorithm showed that the low-risk score group was more susceptible to chemotherapy and immunotherapy. Most patients with mutation genes had a lower risk score than the wild type. Therefore, the risk score signature with cellular senescence-related genes can predict gastric cancer prognosis and identify gastric cancer patients who are sensitive to chemotherapy and immunotherapy.

Development of a Novel Immune-Related Gene Signature to Predict Prognosis and Immunotherapeutic Efficiency in Gastric Cancer

Background: Gastric cancer (GC) is the fifth most common malignancy and the third leading cause of tumor-related deaths globally. Herein, we attempted to build a novel immune-related gene (IRG) signature that could predict the prognosis and immunotherapeutic efficiency for GC patients.

Methods: The mRNA transcription data and corresponding clinical data of GC were downloaded from The Cancer Genome Atlas (TCGA) database as the training group and the GSE84437 data set as the testing cohort, followed by acquisition of IRGs from the InnateDB resource and ImmPort database. Using the univariate Cox regression analysis, an IRG signature was developed. Several immunogenomic analyses were performed to illustrate the associations between the immune risk score and tumor mutational burden, immune cell infiltrations, function of immune infiltration, clinical characteristics, immune subtype, and immunotherapeutic response.

Results: The analysis of 343 GC samples and 30 normal samples from the TCGA database gave rise to 8,713 differentially expressed genes (DEGs) and 513 differentially expressed immune-related genes (DEIRGs) were extracted. The novel IRG signature contained eight DEIRGs (FABP4, PI15, RNASE2, CGB5, INHBE, RLN2, DUSP1, and CD36) and was found to serve as an independent predictive and prognostic factor for GC. Then, the GC patients were separated into the high- and low-risk groups based on the median risk score, wherein the low-risk group presented a better prognosis and was more sensitive to immunotherapy than did the high-risk group. According to the time-dependent ROC curves and AUCs, the immunotherapeutic value of the signature was better than the Tumor Immune Dysfunction and Exclusion (TIDE) and T-cell inflammatory signature (TIS) scores. In addition, the AUCs of the risk score for predicting 1-, 2-, and 3-year OS were 0.675, 0.682, and 0.710, respectively, which indicated that the signature had great predictive power.

Conclusion: This study presents a novel IRG signature based on the tumor immune microenvironment, which could improve the prediction of the prognosis and immunotherapeutic efficiency for GC patients. The powerful signature may serve as novel biomarkers and provide therapeutic targets for precision oncology in clinical practice.

Circular RNA mitochondrial translation optimization 1 correlates with less lymph node metastasis, longer disease-free survival, and higher chemotherapy sensitivity in gastric cancer

Objective

Circular‐mitochondrial translation optimization 1 (circ‐MTO1) inhibits the progression of gastric cancer by regulating the growth, apoptosis, and invasion of tumor cells. However, its clinical potential as a biomarker for gastric cancer remains to be further evaluated. This study aimed to assess circ‐MTO1 expression and its correlation with clinical features and prognosis in gastric cancer patients, as well as the effect of circ‐MTO1 on the sensitivity to chemotherapy in gastric cancer cells.

Methods

Circ‐MTO1 in tumor and adjacent tissues of 97 gastric cancer patients undergoing resection was examined by reverse transcription‐quantitative polymerase chain reaction. HGC‐27 and NCI‐N87 cells transfected by circ‐MOT1 overexpression plasmid (OE‐circ‐MOT1) and negative control (OE‐NC) were treated with 0‒6.4 μM oxaliplatin. Relative cell viability was detected using Cell Counting Kit‐8.

Results

Circ‐MTO1 was insufficiently expressed in gastric tumor tissue (median (interquartile range): 0.403 (0.288‒0.518)) compared with adjacent tissue (median (interquartile range): 1.000 (0.715‒1.524)) (p < 0.001). Besides, tumor circ‐MTO1 was correlated with less lymph node metastasis (p = 0.014) and low TNM stage (p = 0.039), while was not correlated with demographic features or other clinical characteristics (all p > 0.05). Furthermore, tumor circ‐MTO1 high expression was independently correlated with prolonged disease‐free survival (DFS) (p = 0.013, adjusted hazard ratio (95% confidential interval): 0.314 (0.126‒0.782)), but was not correlated with overall survival (p > 0.05). Lastly, in gastric cancer cells, OE‐circ‐MTO1 apparently decreased relative cell viabilities at oxaliplatin concentrations of 0.4, 0.8, 1.6, and 3.2 μM (all p < 0.05).

Conclusion

Circ‐MTO1 correlates with less lymph node metastasis, prolonged DFS, and improved chemotherapy sensitivity in gastric cancer.

Mutation of MUC16 Is Associated With Tumor Mutational Burden and Lymph Node Metastasis in Patients With Gastric Cancer

Background

Lymph node metastasis (LNM) is a critical factor in determining the prognosis of gastric cancer (GC), but its underlying mechanism remains unclear. The tumor mutational burden (TMB) has recently been recognized as a biomarker for predicting prognosis and response to immune checkpoint inhibitors, while mucin 16, cell surface associated (MUC16) is frequently mutated in GC. This study explored whether MUC16 mutation status is associated with TMB, LNM, and prognosis in patients with GC.

Methods

Somatic mutation data were downloaded from three GC cohorts. TMB values were calculated and associations between the TMB and clinical characteristics were analyzed. The mutational landscapes of these three GC cohorts were individually explored and visualized using waterfall diagrams. Univariate logistic regression and Kaplan-Meier survival analysis were performed to screen for mutated genes associated with LNM and overall survival (OS). Associations between MUC16 mutations and TMB, microsatellite instability (MSI), LNM, and tumor microenvironment signatures were explored.

Results

TMB was associated with LNM and OS in patients with GC. Analyzing the three GC cohorts (The Cancer Genome Atlas-Stomach Adenocarcinoma, International Cancer Genome Consortium [ICGC]-China, and ICGC-Japan) revealed that MUC16 was one of the most frequently mutated genes in patients with GC. MUC16 mutations were associated with better prognosis, including lower LNM rates and improved OS rates. In addition, MUC16 mutation status was associated with TMB and MSI statuses. Fifteen upregulated and 222 downregulated genes were identified in patients with MUC16 mutations, compared to in those in patients with wild-type MUC16. An altered tumor microenvironment signature was also identified in GC samples with MUC16 mutations; it was characterized by significantly decreased infiltration regarding stromal cells, CD4+ T cells, and macrophages.

Conclusion

MUC16 mutation status was associated with TMB, microsatellite status, LNM, and survival in patients with GC. These findings may provide new insights into the mechanism of LNM and could act as a signpost for prognostic predictions and immunotherapy guidance for patients with GC.

Targeting autophagy peptidase ATG4B with a novel natural product inhibitor Azalomycin F4a for advanced gastric cancer

Advanced gastric cancer (GCa) remains highly lethal due to the lack of effective therapies. Identifying promising therapeutic targets and developing effective treatment against GCa are urgently needed. Through mRNA and protein analysis of GCa clinical tumor samples, we found that autophagy-related gene 4B (ATG4B) was overexpressed in GCa tumors and that its high expression was associated with patients’ poor prognosis. Knockdown of ATG4B significantly inhibited GCa cell survival and tumor growth. To further probe the role of ATG4B in GCa by pharmacological means, we screened an in-house marine natural compound library against ATG4B and identified Azalomycin F4a (Am-F4a) as a novel and potent ATG4B inhibitor. Am-F4a directly bound to ATG4B with high affinity and effectively suppressed GCa cell autophagy via inhibition of ATG4B both in vitro and in vivo. Moreover, Am-F4a or ATG4B knockdown significantly suppressed tumor growth as well as GCa cell migration and invasion. Am-F4a effectively blocked the metastatic progression of primary GCa and sensitized tumors to chemotherapy. Taken together, our findings indicate that ATG4B is a potential therapeutic target against GCa and the natural product Am-F4a is a novel ATG4B inhibitor that can be further developed for the treatment of GCa.

Establishment and Analysis of an Individualized Immune-Related Gene Signature for the Prognosis of Gastric Cancer

A growing number of studies have shown that immunity plays an important clinical role in the process of gastric cancer (GC). The purpose of this study was to explore the function of differentially expressed immune-related genes (DEIRGs) of GC, and construct a gene signature to predict the overall survival (OS) of patients. Gene expression profiles and clinical data of GC patients were downloaded from TCGA and GEO databases. Combined with immune-related genes (IRGs) downloaded from the ImmPort database, 357 DEIRGs in GC tissues and adjacent tissues were identified. Based on the analysis of Lasso and Cox in the training set, a prognostic risk scoring model consisting of 9 (RBP7, DES, CCR1, PNOC, SPP1, VIP, TNFRSF12A, TUBB3, PRKCG) DEIRGs was obtained. Functional analysis revealed that model genes may participate in the formation and development of tumor cells by affecting the function of cell gap junction intercellular communication (GJJC). According to the model score, the samples were divided into high-risk and low-risk groups. In multivariate Cox regression analysis, the risk score was an independent prognostic factor (HR = 1.674, 95% CI = 1.470–1.907, P &lt; 0.001). Survival analysis showed that the OS of high-risk GC patients was significantly lower than that of low-risk GC patients (P &lt; 0.001). The area under the receiver operating characteristic curve (ROC) of the model was greater than other clinical indicators when verified in various data sets, confirming that the prediction model has a reliable accuracy. In conclusion, this study has explored the biological functions of DEIRGs in GC and discovered novel gene targets for the treatment of GC. The constructed prognostic gene signature is helpful for clinicians to determine the prognosis of GC patients and formulate personalized treatment plans.

Systemic Treatment for Metastatic Biliary Tract Cancer: State of the Art and a Glimpse to the Future

Recent years have seen some breakthroughs in the therapeutic landscape of advanced biliary tract cancer (BTC). Firstly, a better understanding of the molecular background of BTC has led to important improvements in the management of these hepatobiliary malignancies, with the advent of targeted agents representing an unprecedented paradigm shift, as witnessed by the FDA approval of pemigatinib and infigratinib for FGFR2-rearranged and ivosidenib in IDH1-mutant cholangiocarcinoma. In addition, several novel treatments are under assessment, including immune checkpoint inhibitors and combination chemotherapies. In the current review, we provide an overview of systemic treatment for metastatic BTC, summarizing recent clinical data on chemotherapy as well as the main results of targeted therapies and immunotherapy.

PD-L1 Status in Gastric Cancers, Association with the Transcriptional, Growth Factors, AKT/mTOR Components Change, and Autophagy Initiation

Introduction: The programmed death receptor ligand 1 (PD-L1) immunohistochemistry (IHC) assay is a widely used selection method for pembrolizumab treatment in gastric cancer (GC) patients. PD-L1 is the main regulator of immunity in oncogenesis. Material and methods: The study included 38 patients with GC. The combined treatment consisted of neoadjuvant FOLFOX6, or FLOT, chemotherapy and surgery. PD-L1 + tumor status was recorded in 12 patients (CPS > 5), with a negative status recorded in 26 patients. RT-PCR determined the expression of molecular markers. The level of LC3B protein was detected by Western Blotting analysis. Results: An overexpression of PD-1, PD-L2 in the tumor is associated with AKT/mTOR mRNA profile change and autophagy initiation in IHC PD-L1 positive GCs. NACT influences these biological features, modifying the expression of AKT/mTOR components and autophagic flux. In PD-L1 positive cancers, the effect of NACT and molecular markers rearrangements are essential compared to the PD-L1 negative cancers. Conclusion: The IHC PD-L1 status in gastric cancers is the significant marker of cancer progression, recovering the multiple inner mechanisms of cancer spreading and leading to ineffective therapy. Autophagy induction and angiogenesis are found in PD-L1 positive gastric cancers.

Significance of Tumor Mutation Burden Combined With Immune Infiltrates in the Progression and Prognosis of Advanced Gastric Cancer

Gastric cancer (GC) is a serious malignant tumor with high mortality and poor prognosis. The prognosis and survival are much worse for advanced gastric cancer (AGC). Recently, immunotherapy has been widely promoted for AGC patients, and studies have shown that tumor mutation burden (TMB) is closely related to immunotherapy response. Here, RNA-seq data, matched clinical information, and MAF files were downloaded from the cancer genome atlas (TCGA)-STAD project in the TCGA database. The collation and visual analysis of mutation data were implemented by the “maftools” package in R. We calculated the TMB values for AGC patients and divided the patients into high- and low-TMB groups according to the median value of TMB. Then, the correlation between high or low TMB and clinicopathological parameters was calculated. Next, we examined the differences in gene expression patterns between the two groups by using the “limma” R package and identified the immune-related genes among the DEGs. Through univariate Cox regression analysis, 15 genes related to prognosis were obtained. Furthermore, the two hub genes (APOD and SLC22A17) were used to construct a risk model to evaluate the prognosis of AGC patients. ROC and survival curves and GEO data were used as a validation set to verify the reliability of this risk model. In addition, the correlation between TMB and tumor-infiltrating immune cells was examined. In conclusion, our results suggest that AGC patients with high TMB have a better prognosis. By testing the patient’s TMB, we could better guide immunotherapy and understand patient response to immunotherapy.

Significance of Tumor Mutation Burden Combined With Immune Infiltrates in the Progression and Prognosis of Advanced Gastric Cancer

Gastric cancer (GC) is a serious malignant tumor with high mortality and poor prognosis. The prognosis and survival are much worse for advanced gastric cancer (AGC). Recently, immunotherapy has been widely promoted for AGC patients, and studies have shown that tumor mutation burden (TMB) is closely related to immunotherapy response. Here, RNA-seq data, matched clinical information, and MAF files were downloaded from the cancer genome atlas (TCGA)-STAD project in the TCGA database. The collation and visual analysis of mutation data were implemented by the “maftools” package in R. We calculated the TMB values for AGC patients and divided the patients into high- and low-TMB groups according to the median value of TMB. Then, the correlation between high or low TMB and clinicopathological parameters was calculated. Next, we examined the differences in gene expression patterns between the two groups by using the “limma” R package and identified the immune-related genes among the DEGs. Through univariate Cox regression analysis, 15 genes related to prognosis were obtained. Furthermore, the two hub genes (APOD and SLC22A17) were used to construct a risk model to evaluate the prognosis of AGC patients. ROC and survival curves and GEO data were used as a validation set to verify the reliability of this risk model. In addition, the correlation between TMB and tumor-infiltrating immune cells was examined. In conclusion, our results suggest that AGC patients with high TMB have a better prognosis. By testing the patient’s TMB, we could better guide immunotherapy and understand patient response to immunotherapy.

The emerging role of miR-10 family in gastric cancer

Evidence has demonstrated that miRNAs play an irreplaceable role in tumorigenesis and progression of a broad range of cancers, including gastric cancer. Among these miRNAs, miR-10a and miR-10b have been identified to critically participate in gastric carcinogenesis and malignant progression. In this review, we briefly describe the role of miR-10a and miR-10b in gastric cancer, especially in the regulation of cell proliferation, apoptosis, cell cycle, migration, invasion and metastasis, drug resistance, and cancer stem cells. Furthermore, we highlight several compounds that target the miR-10 family and exhibit antitumor activity in cancer cells. Moreover, we conclude that targeting the miR-10 family might be a promising approach for the treatment of gastric cancer.

Adaptive immunity profiling associated with histological subtypes and postoperative survival in gastric cancer

Background

In gastric cancer (GC), abnormal adaptive immunity is correlated with chronic inflammatory disorders and poor prognosis. However, the global study of adaptive immunity involving genes expression is insufficient.

Methods

In this study, we investigated the transcriptional profile of adaptive immunity involving genes in GC from TCGA (The Cancer Genome Atlas). The relevance of adaptive immunity and the clinical features of patients with GC were assessed. Differences in gene expression between each feature and the correlation between gene expression and prognosis were elucidated.

Results

According to the expressional profile of adaptive immunity-related genes, 412 patients with GC were grouped into two primary classifications and three secondary classifications. There were no differences in prognosis detected between each subgroup. In the immune subgroups, the distributions of pathological type were obviously different. Additionally, histological types, AJCC (American Joint Committee on Cancer) stage features, grade, tumor stage, aneuploidy score, and fraction genome altered in different subgroups were significantly discrepant. There were 95 differently expressed genes (DEGs) detected between each histological type, which were represented by LAIR1, BTK and LAT2. According to identification of DEGs in the MSTAD (mucinous stomach adenocarcinoma) and SRCC (signet ring cell carcinoma) types, which were relevant to the best and worst prognosis types, respectively, we constructed a model combining seven genes to recognize the MSTAD type (AUC =0.91) and a model combining six genes to recognize the SRCC type (AUC =0.91). Moreover, the expression of FGL1 gene was notably contrasting among the different histological types, and the high-expression of FGL1 was correlated with a poor prognosis.

Conclusions

This study showed that the expressional patterns of adaptive immunity-related genes are closely related to the histological type of GC, and demonstrated that the expression of immune molecules is correlated to the prognosis. Our results are expected to promote immunological therapy for GC.