Intestinal-type Gastric Cancer Research Articles

Pathogenesis and potential reversibility of intestinal metaplasia - a milestone in gastric carcinogenesis.

Non-cardia gastric cancer remains a major cause of cancer-related mortality worldwide, despite declining incidence rates in many industrialized countries. The development of intestinal-type gastric cancer occurs through a multistep process in which normal mucosa is sequentially transformed into hyperproliferative epithelium, followed by metaplastic processes leading to carcinogenesis. Chronic infection with Helicobacter pylori is the primary etiological agent that causes chronic inflammation of the gastric mucosa, induces atrophic gastritis, and can lead to intestinal metaplasia and dysplasia. Both intestinal metaplasia and dysplasia are precancerous lesions, in which gastric cancer is more likely to occur. Atrophic gastritis often improves after eradication of Helicobacter pylori; however, the occurrence of intestinal metaplasia has been traditionally regarded as "the point of no return" in the carcinogenesis sequence. Helicobacter pylori eradication heals non-atrophic chronic gastritis, may lead to regression of atrophic gastritis, and reduces the risk of gastric cancer in patients with these conditions. In this article, we discuss the pathogenesis, epigenomics, and reversibility of intestinal metaplasia and briefly touch upon potential treatment strategy. Gastric intestinal metaplasia no longer appears to be an irreversible precancerous lesion. However, there are still many controversies regarding the improvement of intestinal metaplasia after Helicobacter pylori eradication.

A Retrospective Analysis of the Lauren Classification in the Choice of XELOX or SOX as an Adjuvant Chemotherapy for Gastric Cancer.

We aim to retrospectively explore the guiding value of the Lauren classification for patients who have undergone D2 gastrectomy to choose oxaliplatin plus capecitabine (XELOX) or oxaliplatin plus S-1 (SOX) as a further systemic treatment after the operation. We collected data of 406 patients with stage III gastric cancer(GC)after radical D2 resection and regularly received XELOX or SOX adjuvant treatment after surgery and followed them for at least five years. According to the Lauren classification, we separated patients out into intestinal type (IT) GC together with non-intestinal type(NIT) GC. According to the chemotherapy regimen, we separated patients into the SOX group together with the XELOX group. Among non-intestinal type patients, the 3-year DFS rates in the SOX group and the XELOX group were 72.5%, respectively; 54.5% (P=0.037); The 5-year OS rates were 66.8% and 51.8% respectively (P=0.038), both of which were statistically significant. The patients of non-intestinal type GC may benefit from the SOX regimen. Differences were counted without being statistically significant with intestinal-type GC in the SOX or XELOX groups.

Abstract 1140: A spatially mapped gene expression signature for intestinal stem-like cells identifies high-risk precursors of gastric cancer

Abstract Gastric intestinal metaplasia (GIM) is a precursor lesion for the intestinal subtype of gastric cancer (GC). A risk stratification tool is the Operative Link on GIM (OLGIM), a system that relies on histopathologic annotation of gastric biopsies. Advanced OLGIM (stages III and IV) have the highest risk of progression to GC. Molecular biomarkers for advanced OLGIM are lacking. We explored transcriptomics biomarkers for advanced OLGIM to aid risk assessment efforts among GC precursors.We used clinical and genomic data from four cohorts: 1) GAPS, a cohort of OLGIM-staged patients (N=303); 2) a subset of confirmed intestinal-type GC from The Cancer Genome Atlas (TCGA, N=198); 3) a compilation of scRNA-seq data (N=40), and 4) a spatial transcriptomics cohort (N=5) with annotated H&E-stained histopathology slides from GC or OLGIM-staged patients.We separated the GAPS bulk RNAseq gene expression dataset into independent discovery (N=88) and validation (N=215) sets. Through a combination of differential expression analysis and co-expression analysis, we identified a discrete set of 100 significantly upregulated genes characterizing advanced OLGIM that were confirmed in the validation set. Importantly, these genes were overexpressed both in the corpus and antrum of the stomach. We leveraged spatial transcriptomics assays to refine this signature to genes overexpressed specifically in GIM foci. We interrogated the TCGA dataset and confirmed these genes to be also expressed in gastric tumors. The final high-risk signature included 26 genes. Single-cell RNAseq analysis revealed these genes to be expressed by aberrant intestinal-like lineages. Further, reference-mapping identified cells resembling mature enterocytes and goblet cells that expressed 16 of these genes, whereas 10 genes from the high-risk signature pinpoint immature intestinal stem-like cells at varying stages of differentiation (duodenum stem cells, duodenum differentiating stem cells, and duodenum transit amplifying cells). Finally, we confirmed expression of 12 of these genes by single-molecule fluorescence in situ hybridization (smFISH), that distinguish differentiated from stem-like lineages in metaplasia and are absent in normal gastric glands in intact tissue sections from GC precursors.Our study identified as signature of 26 genes that are: i) characteristically over-expressed in advanced OLGIM stages, ii) localize specifically to metaplasia, iii) are expressed in gastric tumors, and iv) distinguish differentiated from stem-like cells in GIM. These results provide transcriptomics biomarkers that indicate the establishment and expansion of intestinal stem-like cells in advanced OLGIM, with profound translational implications, as these cells may harbor and expand mutations that predispose advanced OLGIM patients to GC. Citation Format: Ignacio A. Wichmann, Robert J. Huang, Andrew Su, Anuja Sathe, Miranda V. Shum, Susan M. Grimes, Rithika Meka, Alison Almeda, Xiangqi Bai, Jeanne Shen, Quan Nguyen, Manuel Amieva, Joo Ha Hwang, Hanlee P. Ji. A spatially mapped gene expression signature for intestinal stem-like cells identifies high-risk precursors of gastric cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1140.

Identification of Serum Biomarkers to Monitor Therapeutic Response in Intestinal-Type Gastric Cancer.

There are a limited number of clinically useful serum biomarkers to predict tumor onset or treatment response in gastric cancer (GC). For this reason, we explored the serum proteome of the gp130Y757F murine model of intestinal-type gastric cancer (IGC). We identified 30 proteins with significantly elevated expression in early gp130Y757F IGC and 12 proteins that were significantly elevated in late gp130Y757F IGC compared to age- and gender-matched wild-type mice. Within these signatures, there was an overlap of 10 proteins commonly elevated in both early- and late-stage disease. These results highlight the potential to identify serum biomarkers of disease stage. Since IGC in the gp130Y757F model can be reversed following therapeutic inhibition of Interleukin (IL)-11, we explored whether the protein signatures we identified could be used to monitor tumor regression. We compared two different therapeutic modalities and found 5 proteins to be uniquely differentially expressed between control animals and animals halfway through treatment, with 10 differentially expressed at the end of treatment. Our findings highlight the potential to identify reliable biomarkers to track IGC tumor regression in response to treatment.

Clinical and Genetic Characteristics of Early and Advanced Gastric Cancer.

Gastric cancer (GC) persists as the fourth most prevalent cause of global cancer-related mortality, presenting a challenge due to the scarcity of available therapeutic strategies. Precision medicine is crucial not only in the treatment but also in the management of GC. We performed gene panel sequencing with Oncomine focus assay comprising 52 cancer-associated genes and MSI analysis in 100 case-matched gastric cancer cases. A comprehensive analysis of clinical and genetic characteristics was conducted on these genetic results and clinicopathological findings. Upon comparison of clinicopathological characteristics, significant differences between early gastric cancer (EGC) and advanced gastric cancer (AGC) were observed in tumor location (p = 0.003), Lauren classification (p = 0.015), T stage (p = 0.000), and N stage (p = 0.015). The six most frequently mutated genes were PIK3CA (29%, 10/35), ERBB2 (17%, 6/35), KRAS (14%, 5/35), ALK (6%, 2/35), ESR1 (6%, 2/35), and FGFR3 (6%, 2/35). Regarding genetic variation, there was a tendency for the N stage to be higher in GC patients with mutated genes (p = 0.014). The frequency of mutations in GC patients was statistically significantly higher in AGC (n = 24) compared to EGC (n = 11) (odds ratio, 2.792; 95% confidence interval, 1.113 to 7.007; p = 0.026). Six of the ten GC patients carrying mutated genes and exhibiting MSI were classified into intestinal-type and undifferentiated GC, with the location of the tumor being in the lower-third. Among these patients, five harbored mutated PIK3CA, while the remaining patient had a mutation in ALK. Conclusions: AGC patients more frequently exhibited alterations of PIK3CA, KRAS, and ERBB2 as somatic oncogenic drivers, and displayed a higher prevalence of cumulative genetic events, including increased rates of PIK3CA mutations, enhanced detection of immunotherapy biomarkers, and mutations of the ESR1 gene.

Association of methylation silencing of ULK2 via epithelial-mesenchymal transition and differentiated gastric cancers.

404 Background: Diffuse-type gastric cancers (DGC) typically have a poor prognosis related to their invasion and metastasis, in which the epithelial–mesenchymal transition (EMT) is the initiation step. ULK2 plays a role in the autophagy initiation, which might provide a survival advantage in cancer cells. Although knock-down of ULK2 reportedly induces autophagy and EMT in a lung cancer cell line, the mechanism of EMT via the downregulation of ULK2, as well as its clinical significance, remains yet unclear. The present study, therefore, aims at clarifying this mechanism and its clinical significance in gastric cancers. Methods: We examined ULK2 mRNA expression in gastric cancer tissues and normal gastric tissues of healthy people. The effects of knock-downed ULK2 were examined in two gastric cancer cells, which were investigated in terms of their gene expression changes by the mRNA microarray. Furthermore, to investigate the carcinogenic process from normal gastric epithelial cells, we used RGE cells, which were conditionally immortalized normal gastric epithelial cells developed from a transgenic rat. Results: ULK2 mRNA expression of gastric cancer tissues was significantly lower than H. pylori-negative normal tissues. ULK2 was strongly expressed in normal tissues and intestinal-type gastric cancers (IGC) but was scarcely expressed in DGC by immunohistochemical staining. Furthermore, we found that the ULK2 methylation level of gastric cancer tissues was higher than H. pylori-negative normal tissues and IGC. Then, we validated whether knock-down of ULK2 could induce autophagy, cell migration, and EMT in NUGC3 and MKN45 cells. Using mRNA microarray analysis, we confirmed that knock-down of ULK2 changed expressions of oncogenic genes associated with cell migration and EMT. Autophagy inhibitor suppressed cell migration and EMT induced by knock-down of ULK2 in NUGC3 and MKN45. Additionally, we found that knock-down of Ulk2 induced apoptosis in normal gastric epithelial cells. Conclusions: Methylation silencing of ULK2 in gastric cancer cells could induce cell migration and EMT by means of autophagy induction, causing transformation to poorly differentiated cancers.

Polyphenol intake and gastric cancer: A case-control study in the Brazilian Amazon region

BackgroundPolyphenol intake has been associated with a decreased risk of some types of cancer, including gastric cancer (GC). However, few studies address this topic in the Latin American population. In the present study, we evaluated the association between polyphenol intake and the risk of GC in the Brazilian Amazon region. MethodsA case-control study was conducted in Belém (Amazon region) from July 2017 to February 2021. A total of 193 GC cases and 194 controls of both sexes, between 18 and 75 years old, were included in the study. Dietary data were collected using a validated food-frequency questionnaire and polyphenol intake identified using the Phenol-Explorer database. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI), with adjustement for potential confounders. ResultsCases and controls had similar total polyphenol intake (356.4 mg/1000 kcal/d and 331.1 mg/1000 kcal/d, respectively; p = 0.086). After adjusting for potential confounders, high consumption of flavan-3-ols (highest vs. lowest tertile: OR 0.41, 95% CI 0.18–0.94) and hydroxybenzoic acids (highest vs. lowest tertile: OR 0.24, 95% CI 0.10–0.56) was associated with a decreased risk of GC. The opposite was true regarding the intake of flavones (OR 2.46, 95% IC 1.17–5.18) and other polyphenols (OR 2.54, 95% IC 1.16–5.54). When stratifying according to anatomical topography, we observed that the intake of total flavonoids, flavan-3-ols, and flavanones reduced the risk of cardia GC while that of hydroxybenzoic acids reduced the risk of non-cardia GC. In addition, the intake of flavones and other polyphenols was associated with an increased risk of non-cardia GC. According to histologic subtypes, hydroxybenzoic acid intake was associated with a reduced risk of intestinal-type GC (OR 0.21, 95% IC 0.07–0.64), while flavone consumption was associated with an increased risk of diffuse-type GC (OR 2.59, 95% IC 1.05–6.42). ConclusionsOur findings suggest that in the Brazilian Amazon region the high intake of flavan-3-ols and hydroxybenzoic acids is associated with a reduced risk of GC, suggesting a potential beneficial role of these compounds against GC.

The Role of Helicobacter Pylori Infection in the Development of Gastric Cancer - Review of the Literature.

Helicobacter pylori (H. pylori), classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC), is linked to gastric cancer. The progression from atrophy to metaplasia, dysplasia, and carcinoma constitutes the pathway for intestinal-type gastric carcinoma development. H. pylori infection significantly increases gastric cancer risk, particularly in individuals with atrophic gastritis. Virulence factors like CagA and VacA disrupt host signaling pathways, contributing to chronic inflammation and carcinogenesis. Pro-inflammatory cytokines and dysregulated tumor suppressor genes further fuel this process. Eradicating H. pylori reduces gastric cancer incidence, especially in patients with atrophic gastritis and/or intestinal metaplasia. However, it may not prevent cancer in those with advanced pre-neoplastic lesions. Early detection and management of H. pylori infection are crucial in mitigating gastric cancer risk, offering significant benefits.

Does leptin cause proximal gastric cancer in the obese? The role of serum leptin in the etiology of proximal gastric cancer.

The aim of the present study was to determine the correlation between obesity, serum levels of leptin and proximal gastric cancer. Sixty-four gastric cancer patients operated on with curative intent were included in the study. We determined the correlation between the preoperative serum levels of leptin and the tumor's location. Serum leptin levels were correlated significantly with the proximal third location (p=0.04), gastric outlet obstructing tumors (p<0.0001), CRP levels (p=0.03) and BMI (p<0.0001). Patients with high serum levels of leptin had significantly more intestinal types of gastric cancer (p=0.033) and better differentiation (p=0.009). The linear regression model determined the proximal tumor location (beta: 0.467; p=0.045), BMI (beta: 0.657; p=0.001), high preoperative serum albumin (beta: 0.563; p=0.016) and the presence of pyloric stenosis (beta: 0.525; p=0.006) as related significantly to serum leptin levels. The Cox proportional hazard model identified age (HR: 0.003; 95 % CI: 0-0.794; p=0.041), preoperative serum levels of leptin (HR: 0.125; 95 % CI: 0.018-0.887; p=0.037) and the number of extracted LNs (HR: 0.001; 95 % CI: 0-0.677; p=0.038) as independent prognostic factors. Serum levels of leptin were significantly elevated in patients with proximal gastric cancer, suggesting that the leptin's effect might be due to its systemic secretion. This might explain the higher incidence of proximal gastric cancer in obese patients. Elevated serum leptin levels were an independent prognostic factor.

Data-independent acquisition (DIA) mass spectrometry reveals related proteins involved in the occurrence of early intestinal-type gastric cancer.

Identifying proteins associated with the onset of early intestinal-type gastric cancer (EIGC) can yield valuable insights into the pathogenesis of this specific subtype of gastric cancer. Data-independent acquisition mass spectroscopy (DIA-MS) was utilized to identify the differential protein between 10 cases of EIGC and atrophic gastritis with intestinal metaplasia (NGC). The expressions of IPO4, TBL1XR1, p62/SQSTM1, PKP3, and CRTAP were verified by immunohistochemistry (IHC) in 20 EIGC samples, 17 gastric low-grade intraepithelial neoplasia (LGIN) samples, and 21 healthy controls. The prognostic values of the five genes were validated in the transcriptome data by survival analysis. A total of 4,028 proteins were identified using DIA-MS and a total of 177 differential proteins were screened with log2(fold change) > 1.5. Among them, 113 proteins were significantly up-regulated, and 64 proteins were significantly down-regulated in EIGC tissues. IHC results showed that proteins IPO4, TBL1XR1, p62/SQSTM1, PKP3, and CRTAP were highly expressed in the cytoplasm of EIGC and LGIN, which was consistent with the results of DIA-MS. Among them, p62/SQSTM1 may undergo nuclear-cytoplasmic transfer. The five protein-coding genes were associated with intestinal-type gastric cancer survival and exhibited differential expression across various disease stages. The study successfully identified differentially expressed proteins between EIGC and NGC, providing potential biomarkers and valuable insights into the mechanism underlying intestinal-type gastric cancer.

Low incidence of microsatellite instability in gastric cancers and its association with the clinicopathological characteristics: a comparative study

Gastric cancer is a complex heterogeneous disease with different molecular subtypes that have clinical implications. It is characterized by high mortality rates and limited effective therapies. Microsatellite instability (MSI) has been recognized as a subgroup with a good prognosis based on TCGA and ACRG categorizations. Besides its prognostic and predictive value, gastric cancers with high MSI exhibit different clinical behaviors. The prevalence of high MSI has been assessed in gastric cancer worldwide, especially in East Asia, but there is a lack of such information in the Middle East. Therefore, this study aimed to investigate the incidence and status of MSI in Iranian gastric cancer patients using 53 samples collected from 2015 to 2020 at Taleghani Hospital Medical Center. DNA from tumoral and normal tissues were extracted and assessed through multiplex-PCR based on five mononucleotide repeats panel. Clinicopathological variables, including age, sex, Lauren classification, lymph node involvement, TNM stage, differentiation, localization, and tumor size, were also analyzed. With 2 males and 2 females, high microsatellite instability represented a small subgroup of almost 7.5% of the samples with a median age of 60.5 years. High microsatellite instability phenotypes were significantly associated with patients aged 68 years and older (p‑value of 0.0015) and lower lymph node involvement (p‑value of 0.0004). Microsatellite instability was also more frequent in females, with distal gastric location, bigger tumor size, and in the intestinal type of gastric cancer rather than the diffuse type.

The influence of Helicobacter pylori, proton pump inhibitor, and obesity on the gastric microbiome in relation to gastric cancer development

Helicobacter pylori infection is still the main risk factor for the development of gastric cancer (GC). We explore the scientific evidence for the role of the gastric microbiome beyond Helicobacter pylori (H. pylori) in gastric carcinogenesis. The composition of the gastric microbiome in healthy individuals, in presence and absence of H. pylori infection, in proton pump inhibitor (PPI)-users, obese individuals, and GC patients was investigated. Possible mechanisms for microbial involvement, limitations of available research and options for future studies are provided.A common finding amongst studies was increased levels of Streptococcus, Prevotella, Neisseria, and Actinomyces in healthy individuals or those with H. pylori-negative gastritis. In PPI-users the risk for GC increases with the treatment duration, and the gastric microbiome shifts, with the most consistent increase in the genus Streptococcus. Similarly, in obese individuals, Streptococcus was the most abundant genus, with an increased risk for cardia GC. The genera Streptococcus, Lactobacillus and Prevotella were found to be more prominent in GC patients in multiple studies. Potential mechanisms of non-H. pylori microbiota contributing to GC are linked to lipopolysaccharide production, contribution to inflammatory pathways, and the formation of N-nitroso compounds and reactive oxygen species.In conclusion, the knowledge of the gastric microbiome in GC is mainly descriptive and based on sequencing of gastric mucosal samples. For a better mechanistic understanding of microbes in GC development, longitudinal cohorts including precancerous lesions, different regions in the stomach, and subtypes of GC, and gastric organoid models for diffuse and intestinal type GC should be employed.

YAP targetome reveals activation of SPEM in gastric pre-neoplastic progression and regeneration

Peptic ulcer disease caused by environmental factors increases the risk of developing gastric cancer (GC), one of the most common and deadly cancers in the world. However, the mechanisms underlying this association remain unclear. A major type of GC uniquely undergoes spasmolytic polypeptide-expressing metaplasia (SPEM) followed by intestinal metaplasia. Notably, intestinal-type GC patients with high levels of YAP signaling exhibit a lower survival rate and poor prognosis. YAP overexpression in gastric cells induces atrophy, metaplasia, and hyperproliferation, while its deletion in a Notch-activated gastric adenoma model suppresses them. By defining the YAP targetome genome-wide, we demonstrate that YAP binds to active chromatin elements of SPEM-related genes, which correlates with the activation of their expression in both metaplasia and ulcers. Single-cell analysis combined with our YAP signature reveals that YAP signaling is activated during SPEM, demonstrating YAP as a central regulator of SPEM in gastric neoplasia and regeneration.

Exploration of the tumor biological significance of PCLO in gastric cancer - Results from a large Central European cohort.

A recent multiregional whole exome sequencing of 48 tumour samples from 9 gastric adenocarcinomas discovered PCLO mutations in 23 (47.9%) tumour samples. Based on that unexpected high prevalence of PCLO mutations, we hypothesized a tumour biological significance of PCLO in gastric cancer (GC). Tumour samples (whole tissue sections) obtained from 466 patients resected for therapy-naive GC were stained with an anti-PCLO antibody. The Histoscore for tumour cells and the presence of immunostaining of stromal cells and tumour vessels was docu-mented for each case. An algorithm for PCLO immunopositivity was formed and correlat-ed with clinicopathological patient characteristics. 175 GCs were classified as PCLO-positive within tumour cells, and 291 as negative. Stromal cells were positive for PCLO in 106 cases and tumour vessels in 84. PCLO positive GCs more often showed an intestinal phenotype, a lower T-category and were more commonly associated with Helicobacter pylori-infection. A separate analysis of PCLO ex-pression in intestinal and diffuse type GCs, respectively, showed no significant correla-tions. Patients with PCLO negative/low tumour cells showed a shortened overall (14.0±1.4 vs. 16.0±1.8 months) and tumour specific survival (15.0±1.6 months vs. 17.9±3.6). Compar-ison of PCLO's genotype with its phenotype in 48 tumour samples obtained from nine cases showed no direct correlations with missense mutations. Our data provide evidence that PCLO is differentially expressed in GC and might delay tumour progression.

A tuft cell - ILC2 signaling circuit provides therapeutic targets to inhibit gastric metaplasia and tumor development

Although gastric cancer is a leading cause of cancer-related deaths, systemic treatment strategies remain scarce. Here, we report the pro-tumorigenic properties of the crosstalk between intestinal tuft cells and type 2 innate lymphoid cells (ILC2) that is evolutionarily optimized for epithelial remodeling in response to helminth infection. We demonstrate that tuft cell-derived interleukin 25 (IL25) drives ILC2 activation, inducing the release of IL13 and promoting epithelial tuft cell hyperplasia. While the resulting tuft cell - ILC2 feed-forward circuit promotes gastric metaplasia and tumor formation, genetic depletion of tuft cells or ILC2s, or therapeutic targeting of IL13 or IL25 alleviates these pathologies in mice. In gastric cancer patients, tuft cell and ILC2 gene signatures predict worsening survival in intestinal-type gastric cancer where ~40% of the corresponding cancers show enriched co-existence of tuft cells and ILC2s. Our findings suggest a role for ILC2 and tuft cells, along with their associated cytokine IL13 and IL25 as gatekeepers and enablers of metaplastic transformation and gastric tumorigenesis, thereby providing an opportunity to therapeutically inhibit early-stage gastric cancer through repurposing antibody-mediated therapies.

Peritoneal-directed chimeric oncolytic virus CF17 prevents malignant ascites and improves survival in gastric cancer peritoneal metastases

Gastric cancer (GC) peritoneal metastasis (PM) is fatal without effective therapy. We investigated CF17, a new replication-competent chimeric poxvirus, against GC cell lines invitro and PM in an aggressive GCPM mouse model. We performed viral proliferation and cytotoxicity assays on intestinal-type and diffuse-type human GC cell lines following CF17 treatment. At lower MOIs of 0.01, 0.1, there was >80% killing in most cell lines, while in the more aggressive cell lines, killing was seen at higher MOIs of 1.0 and 10.0. We observed reduced peritoneal tumor burden and prolonged survival with intraperitoneal (i.p.) CF17 treatment in nude mice implanted with the resistant GC cell line. At day 91 after treatment, seven of eight mice were alive in the CF17-treated group vs. one of eight mice in the control group. CF17 treatment inhibited ascites formation (0% vs. 62.5% with PBS). Thus, CF17 efficiently infected, replicated in, and killed GC cells in a dose- and time-dependent manner invitro. Invivo, i.p. CF17 treatment exhibited robust antitumor activity against an aggressive GCPM model to decrease tumor burden, improve survival, and prevent ascites formation. These preclinical results inform the design of future clinical trials of CF17 for peritoneal-directed therapy in GCPM patients.

Kinesin Family Member B18 Is Related to Gastric Mucin Phenotype and Contributes to Gastric Cancer Progression by Regulating Epithelial-Mesenchymal Transition

Introduction: Gastric cancer (GC) remains a common health concern worldwide and is the third leading cause of death in Japan. It can be broadly classified into gastric and intestinal mucin phenotypes using immunohistochemistry. We previously reported numerous associations of kinesin family member (KIF) genes and mucin phenotypes with GC. However, no previous studies have reported on the importance of KIF18B in GC using immunostaining. Thus, in this study, we investigated the expression and functions of KIF18B, which is highly expressed in gastric mucin phenotype GC. Methods: We performed RNA-seq of gastric and intestinal mucin type GCs, and clinicopathological studies of the KIF18B we found were performed using 96 GC cases. We also performed functional analysis using GC-derived cell lines. Result: RNA-seq showed the upregulation of matrisome-associated genes in gastric mucin phenotype GC and a high expression of KIF18B. KIF18B was detected in 52 of the 96 GC cases (54%) through immunohistochemistry. Low KIF18B expression was significantly associated with poor overall survival (p < 0.01). Other molecules that were significantly associated with KIF18B were MUC5AC and claudin 18; these were also significantly associated with the gastric mucin phenotype. KIF18B small interfering RNA (siRNA)-transfected GC cells showed greater growth and spheroid colony formation than the negative control siRNA-transfected cells. Furthermore, expression of snail family transcriptional repressor 1 and cadherin 2 was significantly increased and that of cadherin 1 was significantly decreased in KIF18B siRNA-transfected GC cells. Conclusion: These findings not only suggest that KIF18B may be a useful prognostic marker, but also provide insight into the pathogenesis of the GC phenotype.

Impact of Helicobacter pylori infection status on outcomes among patients with advanced gastric cancer treated with immune checkpoint inhibitors

BackgroundGut microbiota composition can influence cancer immunotherapy response. Recent evidence suggests Helicobacter pylori infection may reduce immune checkpoint inhibitor (ICI) efficacy in lung cancer and melanoma, but thorough characterization of...

Efficacy and potential therapeutic mechanism of Weiwei decoction on Spasmolytic polypeptide-expressing metaplasia in Helicobacter pylori-infected and Atp4a-knockout mice

Ethnopharmacological relevanceSpasmolytic polypeptide-expressing metaplasia (SPEM) is characterized by mucus cell morphologies at the base of gastric glands, which is considered advanced SPEM when accompanied with an increase in transcripts associated with intestinal-type gastric cancer. Weiwei decoction (WWD) was modified from "Si-Jun-Zi Tang," which has been used for thousands of years in China against gastric atrophy and metaplasia. Aim of the studyTo investigate the effects and potential mechanisms of WWD against advanced SPEM. Materials and methodsLiquid chromatography-mass spectrometry was employed to analyze the constituents of WWD. Five-month-infected Helicobacter pylori (H. pylori) Sydney strain 1 C57BL/6J mice and 6-week-old ATPase H+/K+ transporting subunit alpha-knockout mice (Atp4a−/−) were given folic acid (1.95 mg/kg) or WWD (13.65 g/kg, 27.30 g/kg, 54.60 g/kg) by gavage for one month. ResultsWWD demonstrated beneficial effects on gastric mucosal pathology and mucus secretion. In H. pylori-infected mice, WWD effectively reduced the expression of GSII and inhibited the mRNA levels of key markers associated with advanced SPEM, including Clu, Cftr, Wfdc2, Dmbt1, and Gpx2. Similarly, in Atp4a−/− mice, WWD significantly decreased the expressions of GSII and Clusterin, and inhibited the mRNA levels of Wfdc2, Cftr, Dmbt1, and Gpx2. Notably, WWD restored the expression of markers for chief cells (PGC, GIF) and parietal cells (ATP4A), particularly in the medium- and high-dose groups, indicating its potential anti-atrophy effect on H. pylori-infected and Atp4a−/− mice. WWD administration resulted in a decline in TFF2 expression to baseline levels, suggesting that the mucous protection mediated by TFF2 was unaffected. Furthermore, the infiltration of CD163+F4/80+ M2 macrophages in the gastric mucosa of H. pylori-infected mice was reduced after WWD treatment, indicating a potential modulatory role of WWD on M2 macrophages. ConclusionWWD exerted protective effects against SPEM in H. pylori-infected and Atp4a−/− mice. The optimal doses of WWD were found to be medium doses in H. pylori-infected mice and high doses in Atp4a−/− mice. These effects include inhibition of transcripts associated with intestinal-type gastric adenocarcinoma, restoration of ATP4A and PGC expression, and reduction of M2 macrophage infiltration. These findings provide valuable insights into the therapeutic effects of WWD on advanced SPEM and highlight its potential as a treatment option.

Integrated analysis of single-cell RNA-seq and bulk RNA-seq to unravel the molecular mechanisms underlying the immune microenvironment in the development of intestinal-type gastric cancer

Intestinal-type gastric cancer (IGC) is the most frequent type of gastric cancer in high-incidence populations. The early stages of IGC growth successively include nonatrophic gastritis (NAG), chronic atrophic gastritis (CAG) and intestinal metaplasia (IM). However, the mechanisms of IGC development through these stages remain unclear. For this study, single-cell RNA-seq data related to IGC were downloaded from the GEO database, and immune cells of the tumor microenvironment (TME) were annotated using R software. Changes in the proportion of immune cells and altered cell-to-cell interactions were explored at different disease stages using R software, with a focus on plasma cells. Additionally, IGC samples from the TCGA database were used for immune cell infiltration analysis, and a Cox proportional risk regression model was constructed to identify possible prognostic genes. The results indicated that for precancerous lesions, interactions between immune cells were mainly dominated by chemokines to stimulate the infiltration and activation of immune cells. In tumors, intercellular movement of upregulated molecules and amplified signals were associated with the tumor necrosis factor family and immunosuppression to escape immune surveillance and promote tumor growth. Regarding prognostic analysis, IGLC3, IGLV1–44, IGKV1–16, IGHV3–21, IGLV1–51, and IGLV3–19 were found to be novel biomarkers for IGC. Our analysis of the IGC single-cell atlas together with bulk transcriptome data contributes to understanding TME heterogeneity at the molecular level during IGC development and provides insights for elucidating the mechanism of IGC and discovering novel targets for precise therapy.