Novel HER2-Directed Treatments in Advanced Gastric Carcinoma: AnotHER Paradigm Shift?

CircVDAC3 sequesters microRNA-592 and elevates EIF4E3 expression to inhibit the progression of gastric cancer

BACKGROUND

Accumulating evidence has shown that circular RNAs (circRNAs) are involved in gastric cancer (GC) tumorigenesis. However, specific functional circRNAs in GC remain to be discovered, and their underlying mechanisms remain to be elucidated.

METHODS

CircRNAs that were differentially expressed between GC tissues and controls were analyzed using a circRNA microarray dataset. The expression of circVDAC3 in GC was determined using quantitative real-time PCR (qRT-PCR), and the structural features of circVDAC3 were validated. Cell function assays and animal experiments were conducted to explore the effects of circVDAC3 on GC. Finally, bioinformatics analysis, fluorescent in situ hybridization, and dual luciferase assays were used to analyze the downstream mechanisms of circVDAC3.

RESULTS

Our results showed that circVDAC3 was downregulated in GC and inhibited the proliferation and metastasis of GC cells. Mechanistically, circVDAC3 acts as a competing endogenous RNA (ceRNA) of miR-592 and deregulates the repression of EIF4E3 by miR-592. EIF4E3 is downregulated in GC and overexpression of miR-592 or knockdown of EIF4E3 in circVDAC3-overexpressing cells weakens the anticancer effect of circVDAC3.

CONCLUSION

Our study provides evidence that circVDAC3 affects the growth and metastasis of GC cells via the circVDAC3/miR-592/EIF4E3 axis. Our findings offer valuable insights into the mechanisms underlying GC tumorigenesis and suggest novel therapeutic strategies.

Prediction of all-cause death and specific causes of death in patients with gastric cancer with liver metastasis: a Surveillance, Epidemiology, and End Results-based study

BACKGROUND

Gastric cancer (GC), considered the fifth most prevalent malignancy, is the fourth leading cause of cancer death worldwide. This cancer is heterogeneous and invasive and often metastasizes to the liver. The survival of patients with GC, especially cancer-specific survival (CSS), is a matter of concern to their families and medical workers in clinical practice. However, efficient tools for early risk prediction are lacking. Thus, this study aimed to develop a nomogram for forecasting the overall survival (OS) and CSS of patients with GC with liver metastasis (GCLM) based on the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Information on individuals with GCLM was acquired from the SEER database from January 2000 to December 2015. Patients' data were randomized into the train cohort and the test cohort. The independent factors for CSS and OS were determined by univariate and multivariate competing risk analyses and Cox proportional hazards analysis, and the nomograms for predicting CSS and OS were constructed. The receiver operating characteristic curve and calibration curve were used to measure the accuracy and calibration of nomograms.

RESULTS

Our study included 4372 patients with GCLM, with 3060 patients in the train set and 1312 in the test set. The mean follow-up period was 12.31 months. The independent factors influencing the OS of patients with GCLM were age, bone metastasis, chemotherapy, grade, lung metastasis, stage, primary site, radiotherapy, surgical primary site, T stage, and tumor size. The concordance Index (C-index) of the constructed nomogram for OS were 0.718 (SE, 0.004) in the train set and 0.0.680 (SE, 0.006) in the test set. The independent factors affecting the CSS of patients with GCLM were age, chemotherapy, grade, lung metastasis, stage, radiotherapy, regional lymph node positive, surgical primary site, and total number of tumors. The C-index for the constructed nomogram for CSS were 0.696 (SE, 0.005) in the train set and 0.696 (SE, 0.008) in the test set.

CONCLUSION

The constructed nomograms showed satisfactory performance in predicting the OS and CSS of patients with GCLM, which can help clinicians formulate follow-up and rehabilitation strategies conducive to survival. At the same time, it can provide more family and social support for high-risk groups.

Prognostic role of MUCIN family and its relationship with immune characteristics and tumor biology in diffuse-type gastric cancer

The main component of O-glycoproteins, mucin, is known to play important roles in physiological conditions and oncogenic processes, particularly correlated with poor prognosis in different carcinomas. Diffuse-type gastric cancer (DGC) has long been associated with genomic stability and unfavorable clinical outcomes. To investigate further, we obtained clinical information and the RNA-seq data of the TCGA-STAD cohort. Through the use of unsupervised clustering methods and GSEA, we identified two distinct clusters, characterized by higher and lower expression of MUC2 and MUC20, denoted as cluster 1 and cluster 2, respectively. Subsequently, employing CIBERSORT, it was determined that cluster 2 exhibited a higher tumor mutation burden (TMB) and a greater abundance of CD8+ T cells and activated CD4+ memory T cells, in addition to immune checkpoints (ICPs). On the other hand, cluster 1 showed a lower TIDE score estimation, indicating a higher probability of tumor immune escape. Furthermore, overexpression of MUC15 and MUC20 was confirmed through qPCR and Western blotting, and their specific roles in mediating the epithelial-mesenchymal transition (EMT) process of GC cells (SNU484 and Hs746t) were validated via CCK-8 assay and wound healing assay in vitro. These findings highlight the potential prognostic value of MUC20 and offer insights into the prospects of immunotherapy for DGC by targeting MUC20.

Circulating miRNA and circulating tumor DNA application as liquid biopsy markers in gastric cancer

Liquid biopsy has been investigated as a novel method to overcome the numerous challenges in gastric cancer (GC) management. This non-invasive, feasible, and easy-to-repeat method has been shown to be cost-effective and capable of increasing diagnostic sensitivity and prognostic assessment. Additionally, it is potentially accurate to aid decision-making and personalized treatment planning. MicroRNA (miRNA) and circulating tumor DNA (ctDNA) markers can enhance GC management in various aspects, including diagnosis (mainly earlier diagnosis and the ability to perform population-based screening), prognosis (more precise stratification of prognosis), and treatment (including more accurate prediction of treatment response and earlier detection of resistance to the treatment). Concerning the treatment-related application, miRNAs' mimics and antagonists (by using two main strategies of restoring tumor suppressor miRNAs and inhibiting oncogene miRNAs) have been shown to be effective therapeutic agents. However, these need to be further validated in clinical trials. Furthermore, novel delivery systems, such as lipid-based vectors, polymeric-based vectors, and exosome-based delivery, have been developed to enhance the performance of these agents. Moreover, this paper explores the current detection and measuring methods for these markers. These approaches are categorized into direct methods (e.g., Chem-NAT, HTG EdgeSeq, and Multiplex Circulating Fireplex) and indirect methods (e.g., Reverse transcription-quantitative polymerase chain reaction (RT-qPCR), qPCR, microarray, and NGS) for miRNA detection. For ctDNA measurement, main core technologies like NGS, digital PCR, real-time PCR, and mass spectrometry are suggested.

Pro-tumorigenic activity of PYCR1 in gastric cancer through regulating the PI3K/AKT signaling

Background

The primary objective of this investigation was to assess the impact of pyrroline-5-carboxylate reductase 1 (PYCR1) on the progression of gastric cancer (GC), specifically focusing on tumor growth and metastatic potential.

Methods

Surgical specimens from patients with different stages of GC were assayed for PYCR1 expression using immunohistochemistry. PYCR1 expression was manipulated by depletion or overexpression approaches in GC cells, and these cells were applied to explore the functional roles of PYCR1. Expression of apoptosis- and metastasis-related markers was quantified through quantitative real-time PCR and Western blot.

Results

Higher PYCR1 expression was ascertained in surgical specimens from patients with GC as compared to noncancerous adjacent tissues. Additionally, PYCR1 overexpression in GC tissues was linked to adverse clinical outcomes. The depletion of PYCR1 in GC cells resulted in a pronounced reduction in proliferation, the induction of apoptosis, and the attenuation of invasion and metastasis. Conversely, its ectopic expression notably augmented proliferation, restricted apoptosis, and stimulated invasion and metastasis. In addition, the knockdown of PYCR1 resulted in a significant elevation in the activation of caspase 3, a key protein involved in apoptosis. This depletion also led to a decrease in the activation or expression of proteins associated with metastasis, such as phosphorylated (p)-phosphatidylinositol 3-kinase (PI3K), p-AKT serine/threonine kinase (AKT), and snail family transcriptional repressor 1 (Snail). Additionally, it resulted in an upregulation of E-cadherin expression. Conversely, the overexpression of PYCR1 notably increased the levels of p-PI3K, p-AKT, and Snail, while simultaneously reducing E-cadherin expression.

Conclusion

PYCR1, by activating PI3K/AKT signaling, assumes a crucial role in governing malignant characteristics of GC cells, including proliferation, apoptosis, and metastasis. These findings underscore the promising potential of PYCR1 as a diagnostic biomarker and a target for tailored therapeutic interventions in patients with GC.

Impact of Complex Apoptotic Signaling Pathways on Cancer Cell Sensitivity to Therapy

Anticancer drugs induce apoptotic and non-apoptotic cell death in various cancer types. The signaling pathways for anticancer drug-induced apoptotic cell death have been shown to differ between drug-sensitive and drug-resistant cells. In atypical multidrug-resistant leukemia cells, the c-Jun/activator protein 1 (AP-1)/p53 signaling pathway leading to apoptotic death is altered. Cancer cells treated with anticancer drugs undergo c-Jun/AP-1-mediated apoptotic death and are involved in c-Jun N-terminal kinase activation and growth arrest- and DNA damage-inducible gene 153 (Gadd153)/CCAAT/enhancer-binding protein homologous protein pathway induction, regardless of the p53 genotype. Gadd153 induction is associated with mitochondrial membrane permeabilization after anticancer drug treatment and involves a coupled endoplasmic reticulum stress response. The induction of apoptosis by anticancer drugs is mediated by the intrinsic pathway (cytochrome c, Cyt c) and subsequent activation of the caspase cascade via proapoptotic genes (e.g., Bax and Bcl-xS) and their interactions. Anticancer drug-induced apoptosis involves caspase-dependent and caspase-independent pathways and occurs via intrinsic and extrinsic pathways. The targeting of antiapoptotic genes such as Bcl-2 enhances anticancer drug efficacy. The modulation of apoptotic signaling by Bcl-xS transduction increases the sensitivity of multidrug resistance-related protein-overexpressing epidermoid carcinoma cells to anticancer drugs. The significance of autophagy in cancer therapy remains to be elucidated. In this review, we summarize current knowledge of cancer cell death-related signaling pathways and their alterations during anticancer drug treatment and discuss potential strategies to enhance treatment efficacy.

A comprehensive radiopathological nomogram for the prediction of pathological staging in gastric cancer using CT-derived and WSI-based features

OBJECTIVE

This study aims to develop and validate an innovative radiopathomics model that combines radiomics and pathomics features to effectively differentiate between stages I-II and stage III gastric cancer (pathological staging).

METHODS

Our study included 200 patients with well-defined stages of gastric cancer divided into a training cohort (n = 140) and a test cohort (n = 60). Radiomics features were extracted from contrast-enhanced CT images using PyRadiomics, while pathomics features were obtained from whole slide images of pathological specimens through a fine-tuned deep learning model (ResNet-18). After rigorous feature dimensionality reduction and selection, we constructed radiomics models (SVM_rad, LR_rad, and MLP_rad) and pathomics models (SVM_path, LR_path, and MLP_path) utilizing support vector machine (SVM), logistic regression (LR), and multilayer perceptron (MLP) algorithms. The optimal radiomics and pathomics models were chosen based on comprehensive evaluation criteria such as ROC curves, Hosmer‒Lemeshow tests, and calibration curve tests. Feature patterns extracted from the best-performing radiomics model (MLP_rad) and pathomics model (SVM_rad) were integrated to create a powerful radiopathomics nomogram.

RESULTS

From a pool of 1834 radiomics features extracted from CT images, 14 were selected to construct radiomics models. Among these, the MLP_rad model exhibited the most robust predictive performance (AUC, training cohort: 0.843; test cohort: 0.797). Likewise, 10 pathomics features were chosen from 512 extracted from whole slide images to build pathomics models, with the SVM_path model demonstrating the highest predictive efficiency (AUC, training cohort: 0.937; test cohort: 0.792). The combined radiopathomics nomogram model exhibited optimal discriminative ability (AUC, training cohort: 0.951; test cohort: 0.837), as confirmed by decision curve analysis (DCA), which indicated superior clinical effectiveness.

CONCLUSION

This study presents a cutting-edge radiopathomics nomogram model designed to predict pathological staging in gastric cancer, distinguishing between stages I-II and stage III. Our research leverages preoperative CT images and histopathological slides to forecast gastric cancer staging accurately, potentially facilitating the estimation of staging before radical gastric cancer surgery in the future.

Long-Term Complete Response to Trastuzumab Deruxtecan in a Case of Unresectable Gastric Cancer

Introduction

Trastuzumab deruxtecan (T-Dxd) has been approved for the treatment of HER2-positive gastric cancer. However, there are only a limited number of cases of gastric cancer where a long-term complete response (CR) has been maintained. Consequently, we report a case of gastric cancer in which long-term CR was maintained.

Case Presentation

A woman in her late 60s underwent a gastrointestinal endoscopy, which revealed a type 2 lesion with ulceration in the lesser curvature of the vestibule, and a biopsy, which revealed an adenocarcinoma. Computed tomography (CT) revealed wall thickening of the gastric antecubital region, metastatic liver tumor, and extra-regional lymph node metastasis; a diagnosis of T4a, N3a, M1 (H, LYN), and cStage IVB (HER2 3+) was confirmed. Trastuzumab, oxaliplatin, and S-1 were administered initially. After 9 months, ascites appeared, and progressive disease was diagnosed. Paclitaxel and ramucirumab were started as second-line treatments but discontinued owing to neutropenia and increasing ascites. Third-line treatment with T-Dxd was initiated, and 11 months later, CT showed the disappearance of metastases. Even after 31 months, the CR was maintained.

Conclusion

To the best of our knowledge, this is one of the few cases in which long-term CR was maintained with third-line T-Dxd treatment. Treatment strategies for patients with gastric cancer to achieve long-term CR require careful consideration.

A Case of Long-Term Survival with Recurrent Liver Metastases from Gastric Cancer Treated with Nivolumab

Introduction

Improvements in overall survival from advanced gastric cancer have recently been reported with nivolumab. However, few reports have described long-term survival after discontinuing treatment.

Case Presentation

A 67-year-old man diagnosed with advanced gastric cancer and abdominal aortic aneurysm initially underwent distal gastrectomy with D2 dissection. Histological examination revealed tub2 and T2N1M0 stage IIA. One month later, endovascular aneurysm repair was performed. Six weeks after gastrectomy, adjuvant chemotherapy with S-1 was started. Six months later, liver metastases were identified and liver segments S1 and S7 were resected. S-1 and oxaliplatin were added postoperatively, but multiple liver metastases recurred. Paclitaxel and ramucirumab, irinotecan, and docetaxel were administered. Liver metastases showed a temporary reduction in size, then enlarged again. Nivolumab was therefore administered and the liver metastases showed a significant reduction in size. The interval between doses gradually increased due to persistent general fatigue. At 28 months after starting nivolumab therapy, bronchitis and adrenal insufficiency appeared, so treatment was discontinued. As of 3.5 years after cessation of nivolumab immunotherapy, tumor regression continued to be maintained. The patient remains alive as of 8 years after recurrence of liver metastases.

Conclusion

We encountered a case in which the patient received nivolumab therapy for recurrent liver metastases from gastric cancer and survived long term after discontinuing treatment.

Prognostic value of T cell immunoglobulin and mucin-domain containing-3 expression in upper gastrointestinal tract tumors: A meta-analysis

BACKGROUND

There is a lack of robust prognostic markers for upper gastrointestinal (GI) tract cancers, including esophageal, gastric, and esophagogastric junction cancers. T cell immunoglobulin and mucin-domain containing-3 (TIM3) plays a key immunomodulatory role and is linked to the prognosis of various cancers. However, the significance of TIM3 in upper GI tract tumors is still uncertain.

AIM

To investigate the prognostic value of TIM3 expression in upper GI tract tumors.

METHODS

A literature search was conducted on the PubMed, Embase, and Web of Science databases for relevant studies published until June 2023. After screening and quality assessment, studies that met the criteria were included in the meta-analysis. Statistical methods were used for the pooled analysis to assess the association of TIM3 expression in upper GI tract tumors with the prognosis and clinicopathological parameters. The results were reported with the hazard ratio (HR) and 95% confidence interval (CI).

RESULTS

Nine studies involving 2556 patients with upper GI tract cancer were included. High TIM3 expression was associated with a worse prognosis in upper GI tract cancer (HR: 1.17, 95%CI: 1.01-1.36). Positive expression of TIM3 in gastric cancer was correlated with the T and N stage, but the difference was not statistically significant. However, TIM3 overexpression was significantly correlated with the TNM stage (odds ratio: 1.21, 95%CI: 0.63-2.33; P < 0.05). TIM3 expression showed no association with the other clinicopathological parameters.

CONCLUSION

High expression of TIM3 in the upper GI tract cancer is associated with a worse prognosis and advanced T or N stages, indicating its potential value as a prognostic biomarker. These findings may provide a basis for the personalized treatment of upper GI tract cancers.

Research progress on the immune microenvironment and immunotherapy in gastric cancer

The tumor microenvironment, particularly the immune microenvironment, plays an indispensable role in the malignant progression and metastasis of gastric cancer (GC). As our understanding of the GC microenvironment continues to evolve, we are gaining deeper insights into the biological mechanisms at the single-cell level. This, in turn, has offered fresh perspectives on GC therapy. Encouragingly, there are various monotherapy and combination therapies in use, such as immune checkpoint inhibitors, adoptive cell transfer therapy, chimeric antigen receptor T cell therapy, antibody-drug conjugates, and cancer vaccines. In this paper, we review the current research progress regarding the GC microenvironment and summarize promising immunotherapy research and targeted therapies.

SERPINB5 is a novel serum diagnostic biomarker for gastric high-grade intraepithelial neoplasia and plays a role in regulation of macrophage phenotypes

BACKGROUND

Gastric cancer (GC) develops from gastric precancerous lesions (GPL), and early diagnosis and treatment at the premalignant stage may achieve a higher benefit‒cost ratio with a reduced necessity for surgery. However, reliable noninvasive screening biomarkers of GPL are currently lacking.

METHODS

The marker genes of GPL encoding extracellular proteins were identified by bioinformatics analysis and further verified by immunofluorescence and immunohistochemistry assays. Serum samples were collected to measure the levels of SERPINB5, the diagnostic efficacy of which was assessed by the area under the receiver operating characteristic (ROC) curve (AUC). Finally, the effect of SERPINB5 on the phenotypic conversion of macrophages was verified by public data and in vitro experiments.

RESULTS

SERPINB5 was identified as an extracellular biomarker of GPL that had good diagnostic efficacy. High expression of SERPINB5 was observed in the epithelial cells and adjacent extracellular matrix on sections of gastric high-grade intraepithelial neoplasia (HGIN). Importantly, SERPINB5 determined in serum was significantly increased in the HGIN group, and the AUC for discriminating between HGIN and chronic gastritis or low-grade intraepithelial neoplasia was 0.9936 and 0.9750, respectively. Moreover, SERPINB5 expression was positively correlated with macrophage infiltration, and M1 marker NOS2 expression, but negatively correlated with M2 marker CSF1R expression. In THP-1-derived macrophages, SERPINB5 upregulated expression of M1-related cytokines TNF-α and IL-12, and M1 marker CD86, but suppressed production of M2-related cytokines TGF-β and IL-10.

CONCLUSIONS

Our study provides evidence that SERPINB5 may serve as a promising noninvasive serum biomarker for gastric HGIN screening and regulate macrophage phenotype conversion.

Peripheral blood nutrient indices as biomarkers for anti‑PD‑1 therapy efficacy and prognosis in patients with advanced gastric cancer

Immunotherapy offers survival benefits for patients with advanced gastric cancer, but not all populations can benefit from immunotherapy. Good nutritional status is fundamental to a patient's immune function and may have an impact on the efficacy of immunotherapy. The present study aimed to investigate changes in prognostic nutritional index (PNI), advanced lung cancer inflammation index (ALI) and albumin-globulin ratio (AGR) values before and after immunotherapy in patients with advanced gastric cancer. The study also aimed to determine the potential association of the aforementioned values with patient outcomes and prognosis. Body mass index (BMI), serum albumin, total protein, peripheral blood lymphocyte, neutrophil, carcinoembryonic antigen (CEA), carbohydrate antigen19-9 (CA19-9) and a-fetoprotein (AFP) data were collected from 195 patients with advanced gastric cancer who underwent immunotherapy from January 2020 to October 2021. In addition, PNI, ALI and AGR values were calculated based on variables in blood collected from the patients within 3 days prior to immunotherapy and 3 weeks after immunotherapy. The results demonstrated that low PNI was associated with elevated CEA levels. Moreover, low ALI levels were associated with reduced BMI levels, elevated AFP levels, PD-L1 negative and first-line treatment. Comparison of responding and non-responding groups revealed that patients who responded to immunotherapy had higher PNI and AGR values than patients who did not respond, both before and after treatment, but had lower CEA and CA19-9 levels after treatment. Furthermore, in the non-responding group, PNI and AGR values were decreased and CEA values were increased following treatment compared with those prior to treatment. The objective response and disease control rates were higher in the high PNI and AGR groups compared with the low PNI and AGR groups, respectively. Moreover, PNI and AGR were found to be independent predictors of the short-term efficacy of immunotherapy for advanced gastric cancer, with cut-off values of 47.18 and 1.29, respectively. Univariate analysis revealed that ALI was associated with the progression-free survival (PFS) of patients, while multivariate analysis demonstrated that baseline PNI and AGR were independent predictors of PFS. In conclusion, tumor progression leads to a decline in the nutritional level of patients, and the present study indicated that effective immunotherapy may alleviate this deterioration to a certain extent. Furthermore, PNI and AGR exhibit potential in predicting the efficacy of immunotherapy and the prognosis of patients with advanced gastric cancer, and may exhibit potential as biomarkers in clinical practice.

A Novel Prognostic Biomarker CCR8 for Gastric Cancer and Anti-CCR8 Blockade Attenuate the Immunosuppressive Capacity of Tregs In Vitro

Objective: To investigate the immunotherapeutic roles and functions of C-C Motif Chemokine Receptor 8 (CCR8) molecule in gastric cancer (GC). Materials and Methods: Clinicopathological features of 95 GC cases were collected by a follow-up survey. The expression level of CCR8 was measured by immunohistochemistry (IHC) staining and analyzed with the cancer genome atlas database. The relationship between CCR8 expression and Clinicopathological features of GC cases was evaluated by univariate and multivariate analysis. Flow cytometry was used to determine the expression of cytokines and the proliferation of CD4+ regulator T cells (Tregs) and CD8+ T cells. Results: An upregulated expression of CCR8 in GC tissues was associated with tumor grade, nodal metastasis, and overall survival (OS). Tumor-infiltrated Tregs with higher expression of CCR8 produced more IL10 molecules in vitro. In addition, anti-CCR8 blocking downregulated IL10 expression produced by CD4+ Tregs, and reversed the suppression by Tregs on the secretion and proliferation of CD8+ T cells. Conclusion: CCR8 molecule could be a prognostic biomarker for GC cases and a therapeutic target for immune treatments.

Assessing synchronous ovarian metastasis in gastric cancer patients using a clinical-radiomics nomogram based on baseline abdominal contrast-enhanced CT: a two-center study

BACKGROUND

To build and validate a radiomics nomogram based on preoperative CT scans and clinical data for detecting synchronous ovarian metastasis (SOM) in female gastric cancer (GC) cases.

METHODS

Pathologically confirmed GC cases in 2 cohorts were retrospectively enrolled. All cases had presurgical abdominal contrast-enhanced CT and pelvis contrast-enhanced MRI and pathological examinations for any suspicious ovarian lesions detected by MRI. Cohort 1 cases (n = 101) were included as the training set. Radiomics features were obtained to develop a radscore. A nomogram combining the radscore and clinical factors was built to detect SOM. The bootstrap method was carried out in cohort 1 as internal validation. External validation was carried out in cohort 2 (n = 46). Receiver operating characteristic (ROC) curve analysis, decision curve analysis (DCA) and the confusion matrix were utilized to assess the performances of the radscore, nomogram and subjective evaluation model.

RESULTS

The nomogram, which combined age and the radscore, displayed a higher AUC than the radscore and subjective evaluation (0.910 vs 0.827 vs 0.773) in the training cohort. In the external validation cohort, the nomogram also had a higher AUC than the radscore and subjective evaluation (0.850 vs 0.790 vs 0.675). DCA and the confusion matrix confirmed the nomogram was superior to the radscore in both cohorts.

CONCLUSIONS

This pilot study showed that a nomogram model combining the radscore and clinical characteristics is useful in detecting SOM in female GC cases. It may be applied to improve clinical treatment and is superior to subjective evaluation or the radscore alone.

Development and validation of a ligand-receptor pairs signature to predict outcome and provide a therapeutic strategy in gastric cancer

BACKGROUND

An important factor in tumor development and progression is the tumor microenvironment (TME), which is heterogeneous. Previous studies have mainly investigated the expression profile and prognostic values of genes in gastric cancer (GC) at the cell population level but neglected the interactions and heterogeneity between cells.

METHODS

The pattern of ligand-receptor (LR) interactions was delineated on a scRNA-seq dataset containing 44,953 cells from nine GC patients and a fourth bulk RNA-seq dataset including data from 1159 GC patients. We then constructed an LR.Score scoring model to comprehensively evaluate the influence of LR-pairs on the TME, overall survival, and immunotherapy response in GC patients from several cohorts.

RESULTS

Cell communication network among 13 cell types was constructed based on the LR-pairs. We proposed a new molecular subtyping model for GC based on the LR-pairs and revealed the differences in prognosis, pathophysiologic features, mutation characteristics, function enrichment, and immunological characteristics among the three subtypes. Finally, an LR.Score model based on LR-pairs was developed and validated on several datasets.

CONCLUSIONS

Based on the selected LR-pairs, we successfully constructed a novel prediction model and observed its well performance on molecular subtyping, target and pathway screening, prognosis judging, and immunotherapy response predicting.

Cost-effectiveness analysis of nivolumab-chemotherapy as first-line therapy for locally advanced/metastatic gastric cancer: a United States payer perspective

OBJECTIVES

Nivolumab, an immune checkpoint inhibitor, was approved by the United States (US) Food and Drug administration as a first-line systemic therapy for locally advanced/metastatic gastric cancer patients. The current study aimed to investigate the cost-effectiveness of nivolumab-chemotherapy combination versus chemotherapy alone as a first-line therapy from a US payer perspective.

METHODS

An economic evaluation was conducted using a partitioned survival model in Microsoft Excel® using data from the CheckMate 649 trial. Three discrete mutually exclusive health states (progression-free, post-progression, and death) were included in the model. The health state occupancy was calculated using the overall survival and progression-free survival curves derived from the CheckMate 649 trial. Cost, resource use, and health utility estimates were estimated from a US payer perspective. Deterministic and probabilistic sensitivity analyses assessed the uncertainty of the model parameters.

RESULTS

Nivolumab-chemotherapy provided additional 0.25 life years compared to chemotherapy alone and the quality-adjusted life years (QALYs) were 0.701 and 0.561, respectively, producing a gain of 0.140 QALYs and an incremental cost-effectiveness ratio of $574,072/QALY.

CONCLUSION

From the US payer perspective, at a willingness to pay threshold of $US150,000/QALY, nivolumab-chemotherapy was not found to be cost-effective as a first-line therapy for locally advanced/metastatic gastric cancer.

Efficacy and safety of CalliSpheres® microspheres drug-eluting beads transarterial chemoembolization in GCLM combined trans-arterial infusion therapy for treating primary focus of gastric cancer: a multi-center retrospective study

BACKGROUND

The purpose of this study was to observe the safety and efficacy of CalliSpheres microspheres drug-eluting beads (DEB) transhepatic arterial chemoembolization (CSM-TACE) for liver metastasis of gastric cancer (GCLM) combined with trans-arterial infusion therapy (TAIT) as the primary focus of gastric cancer.

RESEARCH DESIGN AND METHODS

Unresectable advanced GCLM patients were collected for retrospective analysis. Patients who progressed after chemotherapy or could not receive systematic chemotherapy were selected. CSM-TACE was used for GCLM treatment and oxaliplatin for TAIT of primary focus of gastric cancer. Adverse reactions, tumor reactions, survival rate, and survival time during treatment were recorded, and prognostic factors were analyzed.

RESULTS

Forty-three patients from four oncology centers met inclusion criteria and were enrolled. CSM-TACE averaged (1.51 ± 0.51) times and TAIT averaged (4.58 ± 1.65) times. The follow-up time was 2.5-49 months, and the 6-month, 1-year, and 2-year survival rates were 86.0%, 72.1%, and 41.9%, respectively, with a median overall survival of 11.5 months. The adverse reactions during treatment were grade 1-3. The hazard ratio (HR) of combination therapy was 0.51 (P = 0.040), and the HR of TAIT frequency was 0.34 (P = 0.002), which were independent protective factors affecting prognosis.

CONCLUSIONS

CSM-TAC for GCLM combined with TAIT for primary focus of gastric cancer is safe and efficacious, which is worthy of clinical promotion and application.

An unusual non‑metastatic, mismatch repair‑deficient primary gastric squamous cell carcinoma presenting as a large, exophytic, bleeding tumor: A case report

Primary gastric squamous cell carcinoma (GSCC) is an extremely rare malignancy with a poor prognosis. Despite the improved knowledge regarding its pathogenesis and biology, the treatment options remain limited. The present study reported on the unique case of a mismatch repair-deficient (dMMR) primary GSCC in a 79-year-old woman reporting fatigue and symptoms of upper gastrointestinal tract bleeding. Physical examination revealed abdominal pain at palpation. Gastroscopy revealed a large, exophytic, bleeding tumor. Medical imaging confirmed a mushroom-like polyp in the lumen of the stomach, with no signs of disease spread. Total gastrectomy and D2 lymphadenectomy were performed. Pathological examination of the post-operational material confirmed a well-differentiated SCC invading the mucosa, submucosa and muscle layer. There were no signs of dissemination observed in any of the 32 excised lymph nodes. Notably, according to the last follow-up, the patient remains well, supporting the 5-year GSCC survival rate statistics. To the best of our knowledge, this is the first such GSCC case reported in the Surgical Oncology Outpatient Clinic (Copernicus Memorial Hospital, Lodz, Poland) and these findings add to the limited data on GSCC. Although this is a very rare condition, it should always be considered during the process of diagnosis of gastric tumors.

Deficient Mismatch Repair Proteins in Gastric Mixed Neuroendocrine Non-Neuroendocrine Neoplasm: A Rare Case Report

Mixed neuroendocrine non-neuroendocrine neoplasm (MiNEN) is a rare type of gastric carcinoma with controversial diagnosis and treatment. Recent data implies that deficiency mismatch repair proteins inducing microsatellite instability are considered one of the potential drivers of this disease. Hence, we report a stomach MiNEN with MMR protein loss. An admitted 60-year-old woman complained of epigastric pain. The pathological analysis of the gastro-endoscopic biopsy specimen revealed gastric adenocarcinoma. The radiological staging was cT3N1M0; therefore, she received D2 distal gastrectomy. Suspecting neuroendocrine component admix with adenocarcinoma part on the resected specimen microscopy, applying biomarkers including AE 1/3, synaptophysin, and chromogranin A to confirm the diagnosis of MiNEN. The neuroendocrine part was classified as neuroendocrine tumor grade 2 with Ki 67 at 16.5%. To further understand the molecular characterization of this disease, we evaluated mismatch protein expression by staining MLH1, MSH2, MSH6, and PMS2 antibodies. Interestingly, both components lost MLH1 and PMS2 proteins. Her radical surgery followed oxaliplatin/capecitabine adjuvant chemotherapy. The patient is still well after eight cycles of chemotherapy. dMMR gastric MiNENs and dMMR gastric cancer share many clinical and genetic characteristics. Further studies are necessary to survey the role of dMMR in the prognosis and treatment of this entity.

Krukenberg Tumor of Gastric Origin in Pregnant Women with Preeclampsia

Krukenberg tumor refers to a malignancy in the ovary that metastasizes from a primary site, classically the gastrointestinal tract. Pregnancy complicated with a Krukenberg tumor is very rare. In this report, we present two unusual cases of pregnant women with Krukenberg tumors of gastric origin. One case was a full-term pregnant woman with preeclampsia (PE) who underwent a caesarean section when bilateral enlarged ovaries were incidentally identified. Histopathology of the wedge resection biopsy showed single-ring cell carcinoma; this was followed by gastroscopy, which indicated a gastric origin. The woman received chemotherapy but died 6 months later. Another case was a pregnant woman at 30 gestational weeks with abdominal pain complicated with early-onset PE. Ultrasonography and magnetic resonance imaging showed bilateral enlarged ovaries and elevated tumor markers. Gastroscopy indicated linitis plastica. After an emergency caesarean section, adnexectomy was performed, and postoperative histopathology confirmed a Krukenberg tumor. The woman died 2 months after delivery. Gastrointestinal symptoms during pregnancy may indicate a malignancy of rare gastrointestinal origin. PE complicated with Krukenberg tumors in pregnancy should be considered in future studies.

The impact of changing the funding model for genetic diagnostics and improved access to personalized medicine in oncology

AIM

In January 2017, a new funding model for diagnostic genetic testing in cancer was introduced in Poland.

OBJECTIVES

The aim of this study was to assess the impact of changing the funding model for genetic diagnosis in oncology on improving access to personalized medicine in Poland between 2017 and 2019.

METHODS

The analysis included data on settlements with the National Health Fund for genetic tests in cancer under a contract of the hospital treatment type and under the contract in the type of separately contracted services between 2017 and 2019.

RESULTS

The 150,647 diagnostic genetic tests were reported, which were billed to 111,872 patients. The average number of tests per patient was 1.35. One test was billed to 83.5% of patients, 11.2% of patients had two tests billed, and 5.3% had at least three tests billed. The number of services provided under the hospital treatment contract in 2018 doubled compared to the previous year. For separately contracted services, more than threefold increase in genetic testing performed in 2019 compared to 2018 was observed.

CONCLUSION

our data show that the novel funding model for genetic services introduced in Poland has positive impact on the availability of genetic testing for patients.

An Intestinal Type Gastric Neuroendocrine Tumor: A Case Report

Neuroendocrine tumors (NETs) represent a diverse set of malignancies, originating from the neuroendocrine cells dispersed throughout the body. Their symptoms are associated with the secretion of bioactive peptides by tumor cells. Five-year survival rates depend on the disease stage: 93% for local, 74% for regional, and 19% for metastatic disease. This report describes a case involving a 64-year-old male patient, who was enduring high blood pressure and anemia. His symptomatology included frequent fainting and bloody vomiting without prior bleeding, coupled with persistent abdominal pain and weight loss. A complete blood count revealed microcytic anemia. His condition improved postoperatively after the transfusion of two units of packed red blood cells, normalizing all parameters. Further biochemistry and serology tests did not provide significant insights. However, an upper endoscopy unveiled a deep ulcer below the gastroesophageal junction with ulcer desquamation. A combination of clinical, laboratory, and radiographic data initially indicated a gastric carcinoma of the intestinal type, characterized by extensive extracellular mucin secretion. The surgical intervention led to the extraction of multiple tumors from lymph nodes, culminating in a postoperative diagnosis of a gastrointestinal (GI) mesenchymal tumor. NETs predominantly manifest in the GI tract, initiating primarily in the small intestine but can also originate in the stomach, appendix, colon, and other parts of the GI tract. Their development from neuroendocrine cells enables them to produce high concentrations of hormone-like substances such as neuropeptides and amines.

Oxaliplatin-Associated Takotsubo Cardiomyopathy in a Patient with Metastatic Gastric Cancer: A Case Report

We present the case of a 64-year-old female with stage IV gastric adenocarcinoma, pulmonary, and abdominal wall metastases, and no history of cardiovascular disease. In palliative care, she received systemic cytotoxic treatment with fluorouracil, leucovorin, oxaliplatin, and docetaxel protocol, which was well tolerated over five cycles. During cycle 6, she presented with cardiovascular symptoms with hemodynamic consequences while receiving oxaliplatin injection without docetaxel or 5-fluorouracil. She was transferred to the emergency department and then to the intensive care unit. She developed no complications during the hospital stay and was discharged after 10 days with preserved systolic function and no structural changes at the myocardial level. The electrocardiogram, echocardiogram, cardiac catheterization, and magnetic resonance imaging findings indicated an oxaliplatin-associated Takotsubo syndrome. The immunochemistry analysis showed PD-L1 expression level TPS: 40% and the foundation one genomic profiling revealed high mutation load, microsatellite instability, and HER2 not found. The patient is currently asymptomatic and on pembrolizumab monotherapy with good tolerance and partial treatment response.

Metastatic Salivary Duct Carcinoma with ERBB2 Amplification and Sequential Response to Ado-Trastuzumab Emtansine and Neratinib: A Case Report

Introduction

Salivary duct carcinoma (SDC) is an aggressive and rare subtype of salivary gland carcinoma. Surgical excision and radiotherapy are standard of care for early cancer. Chemotherapies with taxanes and platinum show overall response rates between 39% and 50%. SDCs are often associated with an overexpression of the androgen receptor (AR) and HER2/neu which have recently become druggable targets.

Case Presentation

Here, we report on an 84-year-old male patient with metastatic SDC of the right parotid gland. In 2017, he underwent a right total parotidectomy, a right neck dissection, and an infratemporal fossa clearance followed by 6 weeks of radiotherapy. In 2018, due to metastatic spread in the lungs, bones, and pararenal gland, a pathological workup of the tumor tissue was performed and revealed both AR and HER2 overexpression, respectively. Consequently, he underwent androgen deprivation therapy and, due to asymptomatic progression, sequentially human epidermal growth factor receptor 2 (HER-2)-targeted therapy with ado-trastuzumab emtansine and neratinib, which led to stable disease during the course of about 18 months. The electronically captured patient-reported outcome had demonstrated a good tolerance of all three therapeutic lines.

Conclusion

In conclusion, since effective standard therapeutic treatment options for SDC may often not be tolerable in older patients, the implementation of personalized and adaptive treatments, especially in patients with rare tumor types, might offer valuable treatment options.

Tumor heterogeneity and carcinoma in resected specimens of gastric low-grade dysplasia: A retrospective single center study

Lesions diagnosed as gastric low-grade dysplasia (LGD) may be pathologically upgraded to early gastric cancer (EGC) or high-grade dysplasia (HGD) after endoscopic resection (ER). In this study, we investigated the risk factors for pathological upgrades after ER and assessed the reason for these upgrades by retrospectively analyzing ER data between January 1999 and December 2019. We enrolled patients with LGD confirmed by forceps biopsy; the patients were classified into pathologically concordant (LGD) and upgraded (HGD and EGC) groups according to the pathology of their resected specimen. To determine the risk factors for upgrade, we compared the endoscopic findings of the concordant and upgraded groups via 1:1 matched case-control design. To find the reasons for discordance, all upgraded cases were pathologically re-evaluated. Among 1,643 cases of LGD, pathological upgrades were observed in 423 (25.7%) resected specimens and EGC was found in 111 (6.7%) lesions. After matching the upgraded and concordant cases, lesion sizes exceeding 1.5 cm (odds ratio (OR): 1.8; 95% CI: 1.1-3.0), mucosal nodularity (OR: 10.8; 95% CI: 5.6-21.0), heterogeneous color (OR: 3.0; 95% CI: 1.7-5.3), presence of erosion (OR: 2.7; 95% CI: 1.8-5.3), and open-type gastric atrophy (OR: 2.9; 95% CI: 1.7-4.9) were noted to be significantly associated with upgraded pathology to EGC. Among the EGC cases, 99 (89.2%) were found to have pre-existing dysplasia. In conclusion, endoscopic evaluations should be performed because of possible pathological upgrades and co-existence of carcinomas in LGDs, especially when they exhibit surface nodularity, erosion, heterogeneous color, and large size.

Gastrectomy for Cancer: A 15-Year Analysis of Real-World Data from the University of Athens

Background and Objectives: Encouraging data have been reported from referral centers following gastrointestinal cancer surgery. Our goal was to retrospectively review patient outcomes following gastrectomy for gastric or gastroesophageal junction (GEJ) cancer at a high-volume unit of the University of Athens. Methods: The enrollment period was from June 2003 to September 2018. Disease-free survival (DFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Cox proportional hazard models were constructed to identify variables independently associated with time-to-event outcomes. Results: A total of 205 patients were analyzed. R0 resection was achieved in 183 (89.3%) patients and was more likely to occur following neoadjuvant chemotherapy (p = 0.008). Recurrence developed in 46.6% of our cohort and the median disease-free survival was 31.2 months. On multivariate analysis, only staging (HR = 2.15; 95% CI: 1.06-4.36) was independently associated with increased risk of recurrence. All-cause mortality was 57.2% and the median time of death was 40.9 months. On multivariate regression, staging (HR: 1.35; 95% CI: 1.11-1.65) and recurrence (HR: 2.87; 95% CI: 1.32-6.22) predicted inferior prognosis. Conclusions: Gastrectomy at the University of Athens has yielded favorable outcomes for patients with GEJ cancer.

Recent progress and current challenges of immunotherapy in advanced/metastatic esophagogastric adenocarcinoma

The new era of immunotherapy is successfully implemented in the treatment of metastatic/locally advanced esophagogastric adenocarcinoma (EGAC), as it has been investigated in combinations with/without chemotherapy in human epidermal growth factor receptor 2 (Her2)-positive and Her2-negative tumors. Recent approvals of immune checkpoint inhibitors (ICI) enrich the therapeutic landscape in nearly every therapeutic line. Based on CHECKMATE-649, the combination of nivolumab and chemotherapy in first-line therapy of programmed cell death protein 1 (PD-L1)-positive patients with advanced gastroesophageal junction cancer (GEJC), esophageal cancer (EC), and gastric cancer (GC) was approved in Europe for PD-L1 combined positivity score (CPS) ≥ 5 patients and independently from PD-L1 score in the USA and Asia. Based on KEYNOTE-590, patients with advanced GEJC and EC qualify for the combination of pembrolizumab plus chemotherapy in Europe (CPS ≥ 10) and the USA. For Her2-positive patients, trastuzumab with first-line chemotherapy plus pembrolizumab has beneficial response rates and resulted in approval in the USA (KEYNOTE-811). In third-line therapy, superior overall survival (OS) was achieved by the administration of nivolumab (approval in Japan, ATTRACTION-02), and pembrolizumab shows a positive effect on the duration of response (KEYNOTE-059). Questions of resistance to immunotherapy or the role of gender in response to ICI need to be clarified. This review provides an overview of the current approvals of ICI in advanced EGAC and reflects results of relevant phase II/III trials with focus on possible biomarkers, including PD-L1 CPS and microsatellite-instability (MSI) status.

HELENA: HER2-Low as a prEdictive factor of response to Neoadjuvant chemotherapy in eArly breast cancer

Background

HER2 expression has a prognostic and predictive impact in early-stage breast cancer (BC). HER2 positive BC (immunohistochemistry (IHC) score 3 + or 2 + with in situ hybridization (ISH) amplification) are treated with HER2 targeted therapies. The concept of HER2-low BC (IHC score 1 + or 2 + without ISH amplification) is drawing attention as anti-HER2 treatment has recently shown efficacy in this subgroup. We aimed to explore the response to neoadjuvant chemotherapy (NAC) in HER2-low early BC according to the HER2 score (1 + or 2 + without amplification).

Methods

We conducted a retrospective study in two French comprehensive cancer centers. All patients with HER2-low BC treated with NAC from January 2014 to December 2020 were included. The primary objective was to analyze the pathological complete response (pCR) rate to NAC using the Sataloff or RCB system, according to the HER2 score. Secondary objectives were to assess disease free survival (DFS), overall survival (OS) and to explore the immune environment through the Neutrophil-to-Lymphocyte Ratio (NLR), according to HER2 expression. Univariate and multivariate analyses were performed.

Results

We included 237 tumors for 229 patients. Of these, 160 (67.5%) tumors were HER2 1 + , 77 (32.5%) were HER2 2 + , and 152 (64.1%) were hormone receptor (HR) positive. The median age was 53.9 years. No differences in tumor characteristics were observed between HER2 1 + and HER2 2 + subgroups. pCR was achieved in 38 tumors (17%), without any difference between HER2 1 + and HER2 2 + subgroups (p = 0.77). DFS and OS were significantly different between HER2 1 + and HER2 2 + patients (HR = 0.41,CI95%[0.17;0.97] p = 0.037 and HR = 0.31,CI95%[0.09;1.02] p = 0.042, respectively). HER2 status was still associated with DFS and OS after adjustment for age, HR status and NLR, with better outcomes in favor of HER2 score 2 + (HR = 0.35 [0.15–0.84] and HR = 0.24 [0.07–0.81], respectively). NLR was not associated with worse DFS or OS.

Conclusion

In HER2-low early BC, no differences in pCR were observed between HER2 1 + and HER2 2 + tumors, however patients with HER2 2 + tumors had a better DFS and OS than those with HER2 1 + . Further investigations are needed to describe the intrinsic differences in the spectrum of HER2-low BC.

An Extremely Rare Case of Thyroid Metastasis from Advanced Gastric Cancer

Metastases to the thyroid area are extremely rare in cancer, more specifically, in gastric cancer, where intraperitoneal metastases are absent. Herein, we describe a case of a 41-year-old man who had advanced gastric cancer with metastasis to the right thyroid area, which was found 6 years after curative surgery. The patient presented with multiple enlarged right cervical lymph nodes and a right thyroid mass of 1.2 cm. We assumed that the patient had primary thyroid cancer as he had no signs of other metastases. We performed fine-needle cytology under ultrasonography on the thyroid nodule. However, with a positive carcinoembryonic antigen and a negative thyroid transcription factor 1 immunohistochemical staining results, the patient was diagnosed with metastatic adenocarcinoma that was of gastric origin. Subsequently, the patient was treated with radiotherapy and chemotherapy. This report aimed to raise the concern that gastric cancer may cause metastasis to the peri-thyroid area, involving the thyroid, parathyroid, and regional lymph nodes.

Design Strategies and Precautions for Using Vaccinia Virus in Tumor Virotherapy

Oncolytic virotherapy has emerged as a novel form of cancer immunotherapy. Oncolytic viruses (OVs) can directly infect and lyse the tumor cells, and modulate the beneficial immune microenvironment. Vaccinia virus (VACV) is a promising oncolytic vector because of its high safety, easy gene editing, and tumor intrinsic selectivity. To further improve the safety, tumor-targeting ability, and OV-induced cancer-specific immune activation, various approaches have been used to modify OVs. The recombinant oncolytic VACVs with deleting viral virulence factors and/or arming various therapeutic genes have displayed better therapeutic effects in multiple tumor models. Moreover, the combination of OVs with other cancer immunotherapeutic approaches, such as immune checkpoint inhibitors and CAR-T cells, has the potential to improve the outcome in cancer patients. This will open up new possibilities for the application of OVs in cancer treatment, especially for personalized cancer therapies.

MC180295 Inhibited Epstein–Barr Virus-Associated Gastric Carcinoma Cell Growth by Suppressing DNA Repair and the Cell Cycle

DNA methylation of both viral and host DNA is one of the major mechanisms involved in the development of Epstein–Barr virus-associated gastric carcinoma (EBVaGC); thus, epigenetic treatment using demethylating agents would seem to be promising. We have verified the effect of MC180295, which was discovered by screening for demethylating agents. MC180295 inhibited cell growth of the EBVaGC cell lines YCCEL1 and SNU719 in a dose-dependent manner. In a cell cycle analysis, growth arrest and apoptosis were observed in both YCCEL1 and SNU719 cells treated with MC180295. MKN28 cells infected with EBV were sensitive to MC180295 and showed more significant inhibition of cell growth compared to controls without EBV infection. Serial analysis of gene expression analysis showed the expression of genes belonging to the role of BRCA1 in DNA damage response and cell cycle control chromosomal replication to be significantly reduced after MC180295 treatment. We confirmed with quantitative PCR that the expression levels of BRCA2, FANCM, RAD51, TOP2A, and CDC45 were significantly decreased by MC180295. LMP1 and BZLF1 are EBV genes with expression that is epigenetically regulated, and MC180295 could up-regulate their expression. In conclusion, MC180295 inhibited the growth of EBVaGC cells by suppressing DNA repair and the cell cycle.

Risk Factors and Prognostic Impact of Postoperative Complications in Patients with Advanced Gastric Cancer Receiving Neoadjuvant Chemotherapy

Background: Neoadjuvant chemotherapy is important to improve the prognosis of patients with advanced gastric cancer. However, it may result in postoperative complications (POCs). The aim of this study is to evaluate risk factors and prognostic impact of POCs in patients receiving neoadjuvant chemotherapy. Methods: We retrospectively collected clinical information of patients who underwent curative gastrectomy after receiving neoadjuvant chemotherapy between 2011 and 2018. Overall survival (OS) was analyzed using the Kaplan–Meier method. Logistic regression and Fisher’s exact test were used to evaluate risk factors for complications. Results: A total of 176 patients were included in our study. The 3-year OS rates for the complication group (n = 30) and non-complication group (n = 146) were 36.7% and 52.7%, respectively (p = 0.0294). Age, BMI, multivisceral resection and operation time were independent risk factors for POCs in patients. Patients with multivisceral resection were more likely to suffer from grade III-IV complications (p = 0.026). Inflammation complications might occur in patients with high BMI (p = 0.017). Low preoperative albumin seemed to be a risk factor for leakage complications (p = 0.033). Conclusions: Our study revealed that patients with POCs had a poor prognosis and we identified the risk factors for complications so that POCs can be avoided in time.

Two-in-One Nanoparticle Formulation to Deliver a Tyrosine Kinase Inhibitor and microRNA for Targeting Metabolic Reprogramming and Mitochondrial Dysfunction in Gastric Cancer

Dysregulational EGFR, KRAS, and mTOR pathways cause metabolic reprogramming, leading to progression of gastric cancer. Afatinib (Afa) is a broad-spectrum tyrosine kinase inhibitor that reduces cancer growth by blocking the EGFR family. MicroRNA 125 (miR-125) reportedly diminishes EGFRs, glycolysis, and anti-apoptosis. Here, a one-shot formulation of miR-125 and Afa was presented for the first time. The formulation comprised solid lipid nanoparticles modified with mitochondrial targeting peptide and EGFR-directed ligand to suppress pan-ErbB-facilitated epithelial–mesenchymal transition and mTOR-mediated metabolism discoordination of glycolysis–glutaminolysis–lipids. Results showed that this cotreatment modulated numerous critical proteins, such as EGFR/HER2/HER3, Kras/ERK/Vimentin, and mTOR/HIF1-α/HK2/LDHA pathways of gastric adenocarcinoma AGS cells. The combinatorial therapy suppressed glutaminolysis, glycolysis, mitochondrial oxidative phosphorylation, and fatty acid synthesis. The cotreatment also notably decreased the levels of lactate, acetyl-CoA, and ATP. The active involvement of mitophagy supported the direction of promoting the apoptosis of AGS cells, which subsequently caused the breakdown of tumor-cell homeostasis and death. In vivo findings in AGS-bearing mice confirmed the superiority of the anti-tumor efficacy and safety of this combination nanomedicine over other formulations. This one-shot formulation disturbed the metabolic reprogramming; alleviated the “Warburg effect” of tumors; interrupted the supply of fatty acid, cholesterol, and triglyceride; and exacerbated the energy depletion in the tumor microenvironment, thereby inhibiting tumor proliferation and aggressiveness. Collectively, the results showed that the two-in-one nanoparticle formulation of miR-125 and Afa was a breakthrough in simplifying drug preparation and administration, as well as effectively inhibiting tumor progression through the versatile targeting of pan-ErbB- and mTOR-mediated mitochondrial dysfunction and dysregulated metabolism.

Comparison between talazoparib and conventional chemotherapy in the treatment of HER2-positive breast cancer patients: A retrospective study

Background

The benefits of talazoparib compared with conventional chemotherapy in HER2-negative advanced breast cancer (ABC) remain unclear.

Methods

Patients older than 18 years, with a deleterious germline BRCA1/2 (gBRCA1/2) mutated, metastatic, or locally advanced and HER2-positive breast cancer were enrolled. Patient data including age, menostatus, tumor grade, pathologic tumor size, lymph node status, and whether they had received adjuvant radiation or chemotherapy was collected. The primary outcomes of the study were disease-free survival (DFS), which was defined as the time from randomization to death or recurrence due to any reason, and overall survival (OS), which was defined as the time from randomization to death due to any reason. P<0.05 was considered to be statistically significant.

Results

A total of 136 patients were finally enrolled in the present retrospective study, including 62 patients in the talazoparib group (group A) and 74 in the conventional chemotherapy group (group B). After a median follow-up of 70.9 months [95% confidence interval (CI): 68.3–78.5], both DFS and OS did not differ significantly between the two groups (P=0.658 and P=0.690, respectively). The exploratory subgroup analyses further validated the robustness of the primary results across the subgroups.

Conclusions

Talazoparib was not better than conventional chemotherapy in terms of DFS and OS for the treatment of gBRCA1/2 mutated HER2-positive breast cancer patients.

Evolution of predictive and prognostic biomarkers in the treatment of advanced gastric cancer

Despite new therapeutic options, advanced gastric cancer remains associated with a poor prognosis compared with other cancers. Recent gains in the treatment of gastric cancer were accompanied by the identification of novel biomarkers associated with various cellular pathways and corresponding diagnostic technologies. It is expected that the standardization of clinical workflow and technological refinements in biomarker assessment will support greater personalization and further improve treatment outcomes. In this article, we review the current state of prognostic and predictive biomarkers in gastric cancer.

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.

Polyphenol Mechanisms against Gastric Cancer and Their Interactions with Gut Microbiota: A Review

The lack of new drugs and resistance to existing drugs are serious problems in gastric cancer(GC) treatment. The research found polyphenols possess anti-Helicobacter pylori(Hp) and antitumor activities and may be used in the research and development of drugs for cancer prevention and treatment. However, polyphenols are affected by their chemical structures and physical properties, which leads to relatively low bioavailability and bioactivity in vivo. The intestinal flora can improve the absorption, utilization, and biological activity of polyphenols, whereas polyphenol compounds can increase the richness of the intestinal flora, reduce the activity of carcinogenic bacteria, stabilize the proportion of core flora, and maintain homeostasis of the intestinal microenvironment. Our review summarizes the gastrointestinal flora-mediated mechanisms of polyphenol against GC.

Sex-Biased Immune Responses to Antibiotics during Anti-PD-L1 Treatment in Mice with Colon Cancer

Colitis is a frequently occurred side effect of immune checkpoint inhibitors (ICIs), which are increasingly used in cancer treatment, whereas antibiotics are widely used to treat colitis, their effectiveness in ICI-associated colitis remains controversial. In this study, we firstly assessed the effectiveness of several commonly used antibiotics and antibiotic cocktails in alleviating of dextran sulfate sodium- (DSS-) induced colitis. We observed that two narrow-spectrum antibiotics, neomycin and metronidazole, were more effective in alleviating colitis, as evidenced by the remission of loss of the body weight, enlargement of the spleen, shortening of the colon, secretion of proinflammatory cytokines, and histological score of the colon tissue. Moreover, these two antibiotics resulted in better relief of colitis symptoms in the MC38 tumor-bearing male mice receiving the anti-PD-L1 mAb (αPD-L1) treatment, compared to the females. In the meantime, an enhanced response to αPD-L1 efficiency against mice colon cancer was observed in the male mouse group upon the application of these two antibiotics. In contrast, both neomycin and metronidazole showed destructive effects on the antitumor efficiency of αPD-L1 in female mice, despite relief from colitis. We found that antibiotic treatment attenuated the increased infiltration of granulocytes and myeloid cells in colon tissue induced by DSS in female mice, while reducing the proportion of Th17 cells in male mice. These differences were further associated with the sex-biased differences in the gut microbiota. These findings indicated that sex-dependent alterations in the gut microbiota should be considered when applying antibiotics for the treatment of ICI-associated colitis.

Development and validation of two nomograms for predicting overall survival and cancer-specific survival in gastric cancer patients with liver metastases: A retrospective cohort study from SEER database

•

Nomograms constructed by overall survival and cancer-specific survival can predict more accurately than AJCC stage system for GCLM patients.

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The study includes the prognostic factor as many as possible and evaluated all of them in the cohort.

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In our cohort, surgery is a beneficial factor associated with survival.

Background

Gastric cancer is heterogeneous and aggressive, especially with liver metastasis. This study aims to develop two nomograms to predict the overall survival (OS) and cancer-specific survival (CSS) of gastric cancer with liver metastasis (GCLM) patients.

Methods

From January 2000 to December 2018, a total of 1936 GCLM patients were selected from the Surveillance, Epidemiology, and End Results Program (SEER) database. They were further divided into a training cohort and a validation cohort, with the OS and CSS serving as the study's endpoints. The correlation analyses were used to determine the relationship between the variables. The univariate and multivariate Cox analyses were used to confirm the independent prognostic factors. To discriminate and calibrate the nomogram, calibration curves and the area under the time-dependent receiver operating characteristic curve (time-dependent AUC) were used. DCA curves were used to examine the accuracy and clinical benefits. The clinical utility of the nomogram and the AJCC Stage System was compared using net reclassification improvement (NRI) and integrated differentiation improvement (IDI) (IDI). Finally, the nomogram and the AJCC Stage System risk stratifications were compared.

Results

There was no collinearity among the variables that were screened. The results of multivariate Cox regression analysis showed that six variables (bone metastasis, lung metastasis, surgery, chemotherapy, grade, age) and five variables (lung metastasis, surgery, chemotherapy, grade, N stage) were identified to establish the nomogram for OS and CSS, respectively. The calibration curves, time-dependent AUC curves, and DCA revealed that both nomograms had pleasant predictive power. Furthermore, NRI and IDI confirmed that the nomogram outperformed the AJCC Stage System.

Conclusion

Both nomograms had satisfactory accuracy and were validated to assist clinicians in evaluating the prognosis of GCLM patients.

Signature and Prediction of Perigastric Lymph Node Metastasis in Patients with Gastric Cancer and Total Gastrectomy: Is Total Gastrectomy Always Necessary?

Simple Summary

The signature and prediction of perigastric lymph node metastasis (pLNM) is clinically important, but evidence is still lacking. Here, we aimed to identify an informative signature for the prediction of pLNMs in gastric cancer patients after total gastrectomy, and reassess the current indications for proximal gastrectomy and pylorus-preserving gastrectomy (PPG). We found that proximal gastrectomy may be expanded to patients with stage T1–T2 GC and/or tumor diameter < 4 cm in the upper-third stomach, while PPG may be expanded to include T1–T2/N0 and/or tumors < 4 cm in the middle-third stomach. Furthermore, we developed a new predictive factor, the shortest distance from the pylorus ring to the distal edge of the tumor, which showed good predictive performance for pLNMs.

Abstract

Background: A growing number of studies suggest that the current indications for partial gastrectomy, including proximal gastrectomy and pylorus-preserving gastrectomy (PPG), may be expanded, but evidence is still lacking. Methods: We retrospectively analyzed 300 patients with gastric cancer (GC) who underwent total gastrectomy. We analyzed the incidence of pLNMs in relation to tumor location, tumor size and T stage. We further identified predictive factors for perigastric lymph node metastasis (pLNM) in stations 1, 2, 3, 4sa, 4sb, 4d, 5, and 6. Results: No patients with upper-third T1–T2 stage GC had pLNMs in stations 4sa, 4sb, 4d, 5, or 6, but 3.8% of patients with stage T3 had 4d pLNM. No patients with upper-third GC < 4 cm in diameter had pLNMs in 2, 4sa, 4d, 5, or 6, and 2.3% of patients had pLNMs in 4sb. For middle-third GCs, 2.9% of patients with T1 stage had pLNMs in 4sa and 5, but no patients with T2 stage or tumors < 4 cm had pLNMs in 2, 4sa, or 5. The shortest distance from pylorus ring to distal edge of tumor (sDPD) was a new predictive factor for pLNMs in 2, 4d, 5, and 6. Conclusions: Proximal gastrectomy may be expanded to patients with stage T1–T2 GC and/or tumor diameter < 4 cm in the upper-third stomach, whereas PPG may be expanded to include T1–T2/N0 and/or tumors < 4 cm in the middle-third stomach. A new predictive factor, sDPD, showed good predictive performance for pLNMs, especially in stations 4d, 5, and 6.

Genomically Silent Refractory Gastric Cancer in a Young Patient Exhibits Overexpression of CXCL5

Gastric cancer is the third leading cause of cancer-related deaths, with more than one million new cases and approximately 841,000 deaths annually worldwide. We report a case of a young patient (25 years old) with an aggressive form of gastric cancer. The patient had previously been treated for Helicobacter pylori (H. pylori), which is a main risk factor for developing gastric cancer. Genetic testing showed an E-cadherin (CDH1) germline mutation of unknown significance. After eight cycles of chemotherapy, a positron emission tomography (PET) scan showed disease progression with an enlarging hypermetabolic right adnexal mass suspicious for metastatic disease. Tumor pathology demonstrated invasive and poorly differentiated gastric carcinoma. The analysis of the tumor biopsy indicated the very high expression of a chemokine, C-X-C motif chemokine 5 (CXCL5). The combination of H. pylori infection with an existence of a rare CDH1 mutation could have contributed to this aggressive gastric cancer.

Hepatitis B virus reactivation in patients undergoing immune checkpoint inhibition: systematic review with meta-analysis

PURPOSE

Immune checkpoint inhibitors (ICIs) have been explored as first-line treatment in various types of previously untreatable malignancies, while limited evidence is available on the management of hepatitis B virus (HBV) in patients undergoing immunotherapy. We systematically reviewed data concerning challenges of hepatic adverse events including HBV reactivation and hepatitis in patients with chronic HBV infection undergoing immunotherapy.

METHODS

A systematic search was conducted in Medline, web of science, Embase and Cochrane library up to May 31, 2022. Studies reporting the safety profile of ICIs in patients with HBV infection were eligible. Meta-analyses were conducted to generate odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

A total of 13 studies including 2561 patients were included for meta-analysis. The overall incidence rates of HBV reactivation in patients with chronic HBV infection and past HBV infection were 1.0% (95% CI 0-3%) and 0% (95% CI 0-0%), respectively. Among patients with chronic HBV infection, the incidence rates of HBV reactivation were 1.0% (95% CI 0-2%) and 10.0% (95% CI 4-18%) for patients with and without antiviral prophylaxis, respectively. Patients with chronic HBV infection were at a higher risk of HBV reactivation compared with those with past HBV infection [OR = 8.69, 95% CI (2.16-34.99)]. Antiviral prophylaxis significantly reduced the risk of HBV reactivation [OR = 0.12, 95% CI (0.02-0.67)] and HBV-associated hepatitis [OR = 0.05, 95% CI (0.01-0.28)] in patients with chronic HBV infection.

CONCLUSIONS

Prophylactic antiviral therapy should be administered to patients with chronic HBV infection undergoing anticancer immunotherapy. Patients with past HBV infection are at lower risk of HBV reactivation compared with those with chronic HBV infection, they could be initiated with antiviral prophylaxis or monitored with the intent of on-demand antiviral therapy.

Machine Learning Predictor of Immune Checkpoint Blockade Response in Gastric Cancer

Predicting responses to immune checkpoint blockade (ICB) lacks official standards despite the discovery of several markers. Expensive drugs and different reactivities for each patient are the main disadvantages of immunotherapy. Gastric cancer is refractory and stem-like in nature and does not respond to immunotherapy. In this study, we aimed to identify a characteristic gene that predicts ICB response in gastric cancer and discover a drug target for non-responders. We built and evaluated a model using four machine learning algorithms for two cohorts of bulk and single-cell RNA seq to predict ICB response in gastric cancer patients. Through the LASSO feature selection, we discovered a marker gene signature that distinguishes responders from non-responders. VCAN, a candidate characteristic gene selected by all four machine learning algorithms, had a significantly high prevalence in non-responders (p = 0.0019) and showed a poor prognosis (p = 0.0014) at high expression values. This is the first study to discover a signature gene for predicting ICB response in gastric cancer by molecular subtype and provides broad insights into the treatment of stem-like immuno-oncology through precision medicine.

LC3B, mTOR, AMPK Are Molecular Targets for Neoadjuvant Chemotherapy in Gastric Cancers

Autophagy plays a dual role in oncogenesis processes. On one hand, autophagy enhances the cell resistance to oncogenic factors, and on the other hand, it participates in the tumor progression. The aim of the study was to find the associations between the effectiveness of the FLOT regimen in resectable gastric cancers (GCs) with the key autophagy-related proteins. Materials and Methods: The study included 34 patients with morphologically verified gastric cancer. All patients had FLOT neoadjunvant chemotherapy (NACT) (fluorouracil, leucovorin, oxaliplatin, and docetaxel) followed by gastrectomy. The studied tissue material was the non-transformed and tumor tissues obtained during diagnostic video gastroscopy in patients before the start of the combined treatment and after surgical treatment, frozen after collection. The LC3B, mTOR, and AMPK expression was determined by real-time PCR. The content of the LC3B protein was determined by Western blotting analysis. Results: The mRNA level and the content of the LC3B protein were associated with the tumor stage and the presence of signet ring cells. The AMPK mRNA level was increased in patients with the T4N0-2M0 stage by 37.7 and 7.33 times, which was consequently compared with patients with the T2N0M0 and T3N0-1M0 stages. The opposite changes in the mTOR and AMPK in the GCs before anti-cancer therapy were noted. The tumor size and regional lymph node affections were associated with a decrease in the mTOR mRNA level. A decrease in the mTOR expression was accompanied by an increase in the AMPK expression in the GCs. The mTOR expression was reduced in patients with a cancer spreading; in contrast, AMPK grew with the tumor size. There was an increase in the LC3B expression, which can probably determine the response to therapy. An increase in LC3B mRNA before the start of treatment and the protein content in cancers after NACT with a decrease in therapy effectiveness was recorded. There was an increase in the protein level in patients with partial regression and stabilization by 3.65 and 5.78 times, respectively, when compared with patients with complete tumor regression was noted. Conclusions: The anticancer effectiveness in GCS is down to the LC3B, mTOR, and AMPK expression. These were found to be entire molecular targets affecting the cancer progression and metastasis as well as the NACT effectiveness.

Neoadjuvant Chemoradiotherapy for Locally Advanced Gastric Cancer: Where Are We at?

Simple Summary

More than 50% of gastric cancer are at least locally advanced at presentation. For such patients, a multimodal approach rather than mere surgical resection leads to better long-term prognosis. Neoadjuvant chemoradiotherapy is one of the common treatment strategies for local advanced gastric cancer. Based on the experience and evidence from esophago-gastric cancers, the incorporation of systemic and locoregional therapy has shown superior disease control and reduced local recurrence. However, the optimal chemotherapy regimen, patient selection, technical consideration and potential biomarkers are still under investigation. Furthermore, the comparison of neoadjuvant chemoradiotherapy with neoadjuvant/perioperative chemotherapy is also an important issue to be answered. In the review article, we addressed the current available evidence to provide a comprehensive understanding and the use of neoadjuvant chemoradiotherapy for locally advanced gastric cancer. Future studies and ongoing trials will be necessary to determine the best candidate and the role of newer systemic and radiation therapies in such patients. NCRT is a feasible treatment option for LAGC, with the ability to achieve favorable disease control and enable higher radical resection rates over those afforded by perioperative chemotherapy or surgery alone. Large clinical trials examining the comparative efficacy of NCRT and NCT are underway. The discrepancy between the satisfactory pCR rates associated with NCRT and the nonsignificant association between NCRT and survival warrants further exploration. Furthermore, newer therapies such as immunotherapy and adaptive radiotherapy may be implemented in con-junction with NCRT, and the development of useful biomarkers may ultimately lead to the de-velopment of personalized treatments for LAGC. These research directions may lead to the dis-covery of the optimal approach to administering NCRT to patients with LAGC. They may also aid in the determination of the optimal candidates for undergoing NCRT.

Abstract

Locally advanced gastric cancer (LAGC) has a poor prognosis with surgical resection alone, and neoadjuvant treatment has been recommended to improve surgical and oncological outcomes. Although neoadjuvant chemotherapy has been established to be effective for LAGC, the role of neoadjuvant chemoradiotherapy (NCRT) remains under investigation. Clinical experience and research evidence on esophagogastric junction adenocarcinoma (e.g., cardia gastric cancers) indicate that the likelihood of achieving sustainable local control is higher through NCRT than through resection alone. Furthermore, NCRT also has an acceptable treatment-related toxicity and adverse event profile. In particular, it increases the likelihood of achieving an R0 resection and a pathological complete response (pCR). Moreover, NCRT results in higher overall and recurrence-free survival rates than surgery alone; however, evidence on the survival benefits of NCRT versus neoadjuvant chemotherapy (NCT) remains conflicting. For noncardia gastric cancer, the efficacy of NCRT has mostly been reported in retrospective studies, and several large clinical trials are ongoing. Consequently, NCRT might play a more essential role in unresectable LAGC, for which NCT alone may not be adequate to attain disease control. The continual improvements in systemic treatments, radiotherapy techniques, and emerging biomarkers can also lead to improved personalized therapy for NCRT. To elucidate the contributions of NCRT to gastric cancer treatment in the future, the efficacy, potential toxicity, predictive biomarkers, and clinical considerations for implementing NCRT in different types of LAGC were reviewed.

Gastric Cancer-Derived Extracellular Vesicles (EVs) Promote Angiogenesis via Angiopoietin-2

Simple Summary

Angiogenesis is the formation of new blood vessels, which is essential for gastric cancer growth and metastasis. Angiopoietin-2 is a key driver of tumor angiogenesis and has recently emerged as a promising target for antiangiogenic therapy. Extracellular vesicles play an important role in tumor progression including angiogenesis. We explored the crosstalk between gastric cancer and endothelial cells mediated by vesicles, with a specific focus on angiopoietin-2. We show that primary gastric cancer and omental metastasis tissues express angiopoietin-2. We isolated gastric cancer vesicles and demonstrated that they induce the proliferation, migration, invasion, and tube formation of endothelial cells. Characterization of the angiogenic profile of these vesicles revealed high levels of proangiogenic proteins including angiopoietin-2. Using angiopoietin-2 knockdown, we demonstrate that angiopoietin-2 mediates the proangiogenic effects of the gastric cancer vesicles. Our findings suggest a new mechanism via which gastric cancer cells induce angiogenesis. Such a mechanism may be used as a target for cancer therapy.

Abstract

Angiogenesis is an important control point of gastric cancer (GC) progression and metastasis. Angiopoietin-2 (ANG2) is a key driver of tumor angiogenesis and metastasis, and it has been identified in primary GC tissues. Extracellular vesicles (EVs) play an important role in mediating intercellular communication through the transfer of proteins between cells. However, the expression of ANG2 in GC-EVs has never been reported. Here, we characterized the EV-mediated crosstalk between GC and endothelial cells (ECs), with particular focus on the role of ANG2. We first demonstrate that ANG2 is expressed in GC primary and metastatic tissues. We then isolated EVs from two different GC cell lines and showed that these EVs enhance EC proliferation, migration, invasion, and tube formation in vitro and in vivo. Using an angiogenesis protein array, we showed that GC-EVs contain high levels of proangiogenic proteins, including ANG2. Lastly, using Lenti viral ANG2-shRNA, we demonstrated that the proangiogenic effects of the GC-EVs were mediated by ANG2 through the activation of the PI3K/Akt signal transduction pathway. Our data suggest a new mechanism via which GC cells induce angiogenesis. This knowledge may be utilized to develop new therapies in gastric cancer.

Antigen-Specific T Cell Immunotherapy Targeting Claudin18.2 in Gastric Cancer

Simple Summary

Claudin18.2 is expressed in the primary and metastatic gastric cancer, making Claudin18.2 a suitable target for antigen-specific T cell immunotherapy. In this study, we first identified 12 Claudin18.2 peptides that had immunogenicity, and found that T cells stimulated by Claudin18.2 peptides had stronger anti-tumor activity and higher effective cytokine-secreting ability in vitro. We also found that Claudin18.2 peptide reactivity was associated with older age and higher Claudin18.2 expression, which helped to screen appropriate patients. The value of Claudin18.2 in the T cell-based GC immunotherapy has been affirmed in this study.

Abstract

T cell-based immunotherapy has led to many breakthroughs in the treatment of solid tumors. In this study, we found that membrane protein Claudin18.2 was a promising antigen in T cell-based immunotherapy for gastric cancer (GC). Firstly, we identified five HLA-A*0201- and seven HLA-A*1101-restricted T cell epitopes of Claudin18.2. Peripheral blood mononuclear cells (PBMCs) stimulated by Claudin18.2 peptides showed progressive anti-tumor ability and higher effective cytokine secretion than unstimulated PBMCs in vitro. In total, 81.8% of GC patients were Claudin18.2-positive by immunohistochemical (IHC) detection, and a positive correlation between Claudin18.2 expression and peptide reactivity (p = 0.002) was found. Clinicopathological features analyses demonstrated that Claudin18.2 expression did not correlate with gender, age, stage or Lauren classification. Survival analysis showed that a longer median progression-free survival (mPFS) was not related to peptide reactivity (p = 0.997), but related to a lower Claudin18.2 expression level (p = 0.047). These findings establish a foundation for the clinical application of Claudin18.2 targeted T cell-based immunotherapy in GC.