The gastric precancerous cascade

The impact of Helicobacter pylori and intestinal helminth infections on gastric adenocarcinoma and inflammatory bowel disease in Sub-Saharan Africa

Gastric adenocarcinoma (GCA) is the 5th leading cancer globally with an estimated 1.1 million cases reported in 2020. Ninety percent of non-cardia GCAs are attributable to Helicobacter pylori (H. pylori), the most prevalent bacterial infection globally. Rates of H. pylori infection are highest in Sub-Saharan Africa (SSA), yet surprisingly low numbers of GCAs are reported in the region. A similar phenomenon is seen with the inflammatory bowel diseases (IBD), Crohn's disease, and ulcerative colitis. These disorders have risen dramatically over the past century in high income countries across the globe, with sharp increases noted more recently in newly industrialized regions. In contrast IBD is rare in most regions in SSA. For both diseases this may reflect under-reporting or limited access to diagnostic modalities, but an alternative explanation is the high burden of infection with gastrointestinal parasites endemic to SSA which may attenuate the risk of developing GCA and IBD. In this mini review we discuss the complex interplay between these microorganisms, GCA, and IBD, as well as a possible protective role of H. pylori and the development of IBD.

Anti-Oxidant and Anti-Inflammatory Effects of Astaxanthin on Gastrointestinal Diseases

A moderate amount of reactive oxygen species (ROS) is produced under normal conditions, where they play an important role in cell signaling and are involved in many aspects of the immune response to pathogens. On the other hand, the excessive production of ROS destructs macromolecules, cell membranes, and DNA, and activates pro-inflammatory signaling pathways, which may lead to various pathologic conditions. Gastrointestinal (GI) mucosa is constantly exposed to ROS due to the presence of bacteria and other infectious pathogens in food, as well as alcohol consumption, smoking, and the use of non-steroidal anti-inflammatory drugs (NSAID). Prolonged excessive oxidative stress and inflammation are two major risk factors for GI disorders such as ulcers and cancers. Bioactive food compounds with potent anti-oxidant and anti-inflammatory activity have been tested in experimental GI disease models to evaluate their therapeutic potential. Astaxanthin (AST) is a fat-soluble xanthophyll carotenoid that is naturally present in algae, yeast, salmon, shrimp, and krill. It has been shown that AST exhibits protective effects against GI diseases via multiple mechanisms. Residing at the surface and inside of cell membranes, AST directly neutralizes ROS and lipid peroxyl radicals, enhances the activity of anti-oxidant enzymes, and suppresses pro-inflammatory transcription factors and cytokines. In addition, AST has been shown to inhibit cancer cell growth and metastasis via modulating cell proliferation-related pathways, apoptosis, and autophagy. Considering the potential benefits of AST in GI diseases, this review paper aims to summarize recent advances in AST research, focusing on its anti-oxidant and anti-inflammatory effects against gastric and intestinal ulcers and cancers.

The Microbiome in PDAC-Vantage Point for Future Therapies?

Microorganisms have been increasingly implicated in the pathogenesis of malignant diseases, potentially affecting different hallmarks of cancer. Despite the fact that we have recently gained tremendous insight into the existence and interaction of the microbiome with neoplastic cells, we are only beginning to understand and exploit this knowledge for the treatment of human malignancies. Pancreatic ductal adenocarcinoma (PDAC) is an aggressive solid tumor with limited therapeutic options and a poor long-term survival. Recent data have revealed fascinating insights into the role of the tumoral microbiome in PDAC, with profound implications for survival and potentially therapeutic outcomes. In this review, we outline the current scientific knowledge about the clinical and translational role of the microbiome in PDAC. We describe the microbial compositions in healthy and tumoral pancreatic tissue and point out four major aspects of the microbiome in PDAC: pathogenesis, diagnosis, treatment, and prognosis. However, caution must be drawn to inherent pitfalls in analyzing the intratumoral microbiome. Among others, contamination with environmental microbes is one of the major challenges. To this end, we discuss different decontamination approaches that are crucial for clinicians and scientists alike to foster applicability and physiological relevance in this translational field. Without a definition of an exact and reproducible intratumoral microbial composition, the exploitation of the microbiome as a diagnostic or therapeutic tool remains theoretical.

Endoscopic Grading of Gastric Intestinal Metaplasia Using Magnifying and Nonmagnifying Narrow-Band Imaging Endoscopy

Several endoscopic findings obtained by magnifying image-enhanced endoscopy (IEE) are reportedly correlated with gastric intestinal metaplasia (IM); however, the differences between magnifying and nonmagnifying IEE for the diagnosis of gastric IM remain unknown. This study included 100 consecutive patients who underwent narrow-band imaging endoscopy. Four areas of the stomach were evaluated using nonmagnifying and magnifying IEE. Light-blue crest (LBC), white opaque substance (WOS), and endoscopic grading of the gastric IM (EGGIM) were assessed. The concordance rates between nonmagnifying and magnifying IEE were 80.5% for LBC and 93.3% for WOS. The strength of agreement between each observation technique showed good reproducibility, with a kappa value of 0.69 and 0.83 for LBC and WOS, respectively. The individual EGGIM score indicated a good correlation between nonmagnifying and magnifying IEE (concordance rate, 75%; kappa value, 0.67). The prevalence of a high EGGIM score in patients with and without gastric cancer (GC) showed a significant difference both with nonmagnifying IEE (odds ratio (OR), 3.3; 95% confidence interval (CI), 1.2-9.0), and magnifying IEE (OR, 3.1; 95% CI, 1.1-8.9). Nonmagnifying IEE has the potential to stratify the individual risk of GC, similar to magnifying IEE, warranting further investigation with histological assessment.

Community prevalence of Helicobacter pylori and dyspepsia and efficacy of triple therapy in a rural district of eastern Uganda

Background

Helicobacter pylori (H. pylori) infection and chronic dyspepsia represent significant medical burdens in the developing world. An accurate assessment of the prevalence of chronic dyspepsia, as well as of the effectiveness of population-based screening and eradication of H. pylori are warranted.

Objectives

We determined the prevalence of H. pylori and chronic dyspepsia within the general adult population in a region of eastern Uganda. Independent predictors of H. pylori infection were assessed. Finally, we evaluated the efficacy of standard triple therapy on H. pylori eradication.

Methods

Of 400 randomly selected adult residents in eastern Uganda, 376 were administered a validated, chronic dyspepsia questionnaire and provided a stool sample for H. pylori testing. H. pylori-positive participants were given standard triple therapy and monitored for medication adherence. The efficacy of triple therapy on H. pylori eradication was determined by fecal antigen testing after treatment. Log-linear and logistic regression analyses identified predictors of H. pylori positivity and eradication failure.

Results

H. pylori prevalence within the study population was 48%. The prevalence of chronic dyspepsia was 87%. The presence or severity of dyspepsia did not predict H. pylori infection. However, a higher level of education was an independent predictor of H. pylori infection. Standard triple therapy resulted in ∼90% eradication. Missing at least four doses of any of the triple therapy medications over the 14-day course predicted eradication failure.

Conclusions

In our study population, chronic dyspepsia did not predict H. pylori infection, though clinical suspicion for this prevalent pathogen should nonetheless remain high. Population-based screening and adherence to triple therapy are effective at eradicating H. pylori within this region.

Histopathologically defined intestinal metaplasia in lesser curvature of corpus prior to Helicobacter pylori eradication is a risk factor for gastric cancer development

BACKGROUND AND AIM

Helicobacter pylori eradication has been shown to reduce the risk of gastric cancer (GC), with the number of eradication therapy cases on the rise. However, GC can still occur after successful treatment, and the histological differences prior to eradication in patients with and without GC are unclear. This study investigated the pre-treatment histological risk factors for GC development following eradication therapy.

METHODS

We retrospectively enrolled consecutive adult patients diagnosed as having H. pylori infection between April 2004 and December 2018. Atrophy and intestinal metaplasia (IM) were histologically assessed according to the updated Sydney System. The operative link on gastritis assessment and the operative link on gastric intestinal metaplasia (OLGIM) were evaluated as well.

RESULTS

Of the 247 patients analyzed in this study, 11 (4.5%) experienced GC after eradication therapy. Histological IM scores in the GC group were significantly higher at all gastric biopsy sites (p < .05), and the proportion of OLGIM III/IV stage was significantly greater in GC patients (81.8% vs. 31.8%, p < .01). For GC prediction, the area under the receiver operating characteristic curve for IM score at the lesser curvature of the corpus was the highest among all biopsy sites and not inferior to OLGIM results.

CONCLUSIONS

Patients with histological IM prior to H. pylori eradication, especially at the lesser curvature of the corpus, may be at elevated risk for GC development after eradication therapy and require close surveillance.

Study on molecular biological mechanism of Chinese herbal medicines for the treatment of gastric precancerous lesions based on data mining and network pharmacology

OBJECTIVE

To explore the molecular biological mechanisms of Chinese herbal medicines for the treatment of gastric precancerous lesions by data mining and network pharmacology.

METHODS

The keywords "gastric precancerous lesions""gastric precancerous disease""gastric mucosal intraepithelial neoplasia""gastric mucosal heterogeneous hyperplasia""gastric precancerous state""chronic gastritis, atrophic""combined Chinese and Western medicine""Chinese medicine therapy""efficacy evaluation" "randomized controlled trial"were searched in China Journal Full-text Database, Wanfang Data, VIP database, PubMed and Embase from 2001 to 2021. The information was extracted from the literature which met the inclusion and exclusion criteria, and the database was constructed to identify the high-frequency herbal medicines. The top six Chinese herbal medicines were analyzed by the network pharmacology methods, including the acquisition of herbs compounds and gastric precancerous lesions targets using Pharmacology Database and Analysis Platform and GeneCards databases, construction of protein-protein interaction network, and screening of core targets, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of core targets through Metascape platform, etc., to elucidate their active components, targets and pathways.

RESULTS

A total of 482 compound prescriptions with 603 herbal medicines were included, and the top 6 herbal medicines with higher application frequency were Ume plum (63.35%), Curcuma longa (58.54%), Paeonia lactiflora (54.06%), Salvia miltiorrhiza (49.92%), Rhizoma alba (46.43%), and Astragalus membranaceus (45.44%). The results of the network pharmacological analysis showed that the active ingredients were 4 types from Ume plum, 3 from Curcuma longa, 9 from Paeonia lactiflora, 13 from Salvia miltiorrhiza, 7 from Astragalus alba, and 9 from Astragalus; 77 predicted targets were in Ume plum, 11 in Curcuma longa, 33 in Paeonia lactiflora, 58 in Salvia miltiorrhiza, 65 in Astragalus alba and 89 in Astragalus; and 98 crossover genes were obtained after these targets were compared with the disease genes, among which HSP90AA1, AKT1, TP53, STAT3, MAPK1 and TNF had higher relevance to the treatment of gastric precancerous lesions. The results of the GO enrichment analysis showed that the active ingredients of high frequency Chinese medicine mostly acted through biological processes such as response to inorganic substance, response to hormone, gland development, positive regulation of cell migration, positive regulation of cell motility, etc. The targets include cellular components such as vesicle lumen, secretory granule lumen, cytoplasmic vesicle lumen, transcription regulator complex, and with molecular functions such as kinase binding, protein kinase binding and DNA-binding transcription factor binding. The results of the KEGG pathway enrichment analysis showed that Paeonia lactiflora, Ulmus lucidus, Salvia miltiorrhiza and Astragalus mainly act through the cancer pathway and PI3K-AKT pathway; Curcuma longa and Rhizoma alba mainly act through the cancer pathway and proteoglycans in cancer, and all six herbs were involved in the cancer pathway and five herbs are involved in the PI3K-AKT pathway.

CONCLUSION

In this study, we obtained the top 6 high-frequency Chinese herbal medicines in the treatment of gastric precancerous lesions by data mining method, and revealed that their mechanisms are involved in cell proliferation, differentiation, immunity, inflammation and other processes mainly through cancer pathway, PI3K-AKT signaling pathway, proteoglycans in cancer.

Predicting Gastric Intestinal Metaplasia in a High-Risk Population

INTRODUCTION

Gastric intestinal metaplasia (GIM) is a precancerous lesion. It has a low prevalence rate in the United States. However, GIM is more common among non-White and immigrant populations. Harlem Hospital serves a community that includes predominantly African Americans, Hispanics, and immigrants from West Africa and Spanish-speaking Caribbean countries. This study aims to define the factors predicting GIM in this high-risk group as well as help define screening strategies for vulnerable populations.

METHODS

A total of 1351 patients who underwent endoscopic gastroduodenoscopy (EGD) and biopsy in 2018 and 2019 for any indication at Harlem Hospital were included in this study. Gastric biopsy specimens taken during the procedure were assessed for GIM by histopathology. Baseline demographics were collected, including age, sex, and ethnicity. Other information collected included risk factors for GIM such as Helicobacter pylori infection, smoking status, and the use of alcohol. Descriptive analysis was done and the Wilcoxon rank sum test and chi-squared test were used to test for associations. Multiple logistic regressions were used to assess the odds of independent factors associated with increased risk of GIM.

RESULTS

Of the 1351 patients reviewed, 106 had GIM for a prevalence of 8.0% (CI: 6.7%-9.6%, p < 0.001). Univariate analysis revealed older patients, males, history of smoking, alcohol, and H. pylori infection were significantly associated with GIM. Using multiple logistic regressions and adjusting for underlying risk factors, smoking (OR: 1.61, 95% CI: 1.00-2.570) and H. pylori infection (OR: 3.35, 95% CI: 2.18-5.15) continued to be significantly associated with increased risk of GIM; however, alcohol use was not significant after adjusting for other risk factors (OR: 1.10, 95% CI: 0.68-1.78). Hispanic risk for GIM was slightly higher than African Americans (OR: 1.17, 95% CI: 0.74-1.83). The predicted marginal effect of age on the odds of GIM was significant from age 40 and increased exponentially at age 50. By age 70, the odds of GIM were as high as 11% (95% CI: 8.3-13.6).

CONCLUSION

The prevalence of GIM in our population is significantly higher compared to reported cases in the United States. Age, male gender, H. pylori infection, and smoking significantly increase the risk of GIM. Given the high prevalence of GIM in our population, early endoscopic screening would play an important role in evaluating dyspepsia to diagnose GIM with or without H. pylori infection. We propose screening all at-risk ethnicities from age 40 years with EGD according to the Sydney System biopsy protocol. We believe this will ultimately decrease the incidence of gastric cancer death in these vulnerable populations of color.

Evolution of the Correa's cascade steps: A long-term endoscopic surveillance among non-ulcer dyspepsia and gastric ulcer after H. pylori eradication

BACKGROUND

This study is aimed toward investigating the evolution of each Correa's step after Helicobacter pylori eradication in a long-term follow-up and exploring the factors correlated with a high-risk of gastric cancer.

METHODS

A total of 1824 H. pylori-infected subjects were enrolled to receive screening endoscopy. Among them, 491 received surveillance endoscopy. The patients were divided into Correa's steps I to VI, from normal to gastric cancer. A group-based trajectory model was used to classify patients as persistent high-risk status or not.

RESULTS

The prevalence rates of positive corpus-predominant gastritis index (CGI) were 20%-40% in all age groups and Correa's steps IV-V increased >35% after 50 years based on screening endoscopy. Successful eradication of H. pylori regressed CGI after the 1st year-and-thereafter (P < 0.05) and decreased Correa's step progression (Relative risk 0.66 [95% CI 0.49-0.89], P = 0.01); however, it did not regress OLGA and OLGIM. Not only in steps IV-V, but also in step III, the patients had a risk of developing gastric cancer (11.13-76.41 and 4.61 per 1000 person-years). Age (Hazard ratio 1.012 [1.003-1.020], P = 0.01), OLGA stages ≥ I (2.127 [1.558-2.903], P < 0.001), and OLGIM stages ≥ I (1.409 [1.119-1.774], P = 0.004) were correlated independently with a persistent high-risk status.

CONCLUSION

The patients in Correa's steps III-V, but not I-II, were at risk of gastric cancer after H. pylori eradication. Age, OLGA stages ≥ I, and OLGIM stages ≥ I were independent factors correlated to a persistent high-risk of gastric cancer. The data may be useful when scheduling surveillance endoscopy for subjects in each Correa's step (NCT04527055).

Plasma-Methylated SEPT9 for the Noninvasive Diagnosis of Gastric Cancer

Background. Gastric cancer (GC) is one of the most prevalent cancers globally. This study was designed to evaluate the potential performance of plasma SEPT9 methylation (mSEPT9) as a noninvasive biomarker for the diagnosis of GC. Methods. A total of 182 participants, i.e., 60 patients with GC, 39 with chronic superficial gastritis (CSG), 27 with chronic atrophic gastritis (CAG), 30 with gastric ulcer (GU), and 26 with gastric polys (GP), were recruited. The mSEPT9 level was measured using real-time polymerase chain reaction. Results. As a diagnostic target, mSEPT9 (1/3 algorithm) had a sensitivity of 48.33 (95% confidence interval (CI): 35.40–61.48%) and a specificity of 86.89% (95% CI: 79.28–92.09%), and mSEPT9 (2/3 algorithm) had a sensitivity of 33.33 (95% CI: 22.02–46.79%) and a specificity of 98.36% (95% CI: 93.61–99.72%). The area under the receiver operating characteristic curve (ROC) curve of mSEPT9 was 0.698 (95% CI: 0.609–0.787) for the differentiation of GC from benign gastric diseases. The effectiveness of mSEPT9 (1/3 algorithm) was superior to that of CEA, CA19-9, and CA72-4. mSEPT9 was positively correlated with T, N, M, and the clinical stage of GC. Conclusions. Plasma mSEPT9 might serve as a useful and noninvasive biomarker for the diagnosis of GC.

Diagnostic performances of pepsinogens and gastrin-17 for atrophic gastritis and gastric cancer in Mongolian subjects

In Mongolia, gastric cancer morbidity and mortality are high, and more than 80 percent of cases are diagnosed at an advanced stage. This study aimed to evaluate pepsinogens (PGIs) and gastrin-17 (G-17) levels and to determine the diagnostic performances for gastric cancer and chronic atrophic gastritis among Mongolian individuals. We enrolled a total of 120 subjects, including gastric cancer (40), atrophic gastritis (40), and healthy control (40), matched by age (±2) and sex. Pepsinogen I (PGI), Pepsinogen II (PGII), G-17, and H. pylori IgG levels were measured using GastroPanel ELISA kit (Biohit, Helsinki, Finland). Also, PGI to PGII ratio (PGR) was calculated. For atrophic gastritis, when the optimal cut-off value of PGI was ≤75.07 ng/ml, the sensitivity and specificity were 75% and 50%, respectively; when the optimal cut-off value of PGR was ≤6.25, sensitivity and specificity were 85% and 44.7%, respectively. For gastric cancer, when the optimal cut-off value of PGI was ≤35.25 ng/ml, the sensitivity and specificity were 47.2% and 86.8%, respectively; when the optimal cut-off value of PGR was ≤5.27, sensitivity and specificity were 75% and 60.5%, respectively. Combinations of biomarkers with risk factors could improve diagnostic accuracy (AUC for atrophic gastritis 74.8, 95% CI 64.0–85.7, p<0.001; AUC for gastric cancer 75.5, 95% CI 64.2–86.8, p<0.001). PGI, PGR biomarkers combined with the risk of age, family history of gastric cancer, and previous gastric disease could not be an alternative test for upper endoscopy but might be a supportive method which is identifying individuals at medium- and high risk of gastric cancer and precancerous lesions who may need upper endoscopy.

Features of diet therapy for H. pylori associated diseases of the gastrointestinal tract

This review of the literature is devoted to the importance of nutritional support in the treatment and prevention of diseases of the gastrointestinal tract associated with Helicobacter pylori. Modern data on the biological properties of H. pylori and the mechanisms of colonization of the microorganism in the gastrointestinal mucosa are presented. Information is provided on the virulence factors and factors that promote adhesion, depolymerization and dissolution of protective mucus, damage and circulatory disorders of the gastrointestinal mucosa, secreted by H. pylori (lipopolysaccharides and proteins of the outer shell of the bacterium, enzymes – mucinase, protease, phospholipase, urease, VacA cytotoxin). The article pays special attention to the issues of diet therapy, the role of various foods and their components in the dietary correction of disorders in gastrointestinal diseases associated with H. pylori. The causes of nutritional disorders in patients with gastrointestinal diseases are described and a detailed description of food products and their biologically active components with anti-Helicobacter activity is given. A special section is devoted to the use and effectiveness of specialized dietary products for therapeutic and preventive nutrition of domestic production (LLC “Leovit nutria”) and the features of use in diseases of the gastrointestinal tract mediated by H. pylori. The authors provide information on the composition of dietary products, their anti-inflammatory, antioxidant, immunotropic and other activities that underlie clinical efficacy. The article provides detailed recommendations on the use of specialized dietary foods for this pathology.

Gastric Cancer After Helicobacter pylori Eradication for Nodular Gastritis in an Adolescent

A 16-year-old girl underwent esophagogastroduodenoscopy (EGD) after the detection of Helicobacter pylori (H. pylori) antibodies in her urine during a school health screening, which revealed nodular gastritis (NG). She was diagnosed as having H. pylori infection histologically and by biopsy culture specimens and soon commenced eradication therapy. Eight weeks later, eradication was confirmed by a urea breath test. At the age of 19, however, she was referred to our hospital with epigastralgia and lower back pain. EGD revealed ulcerative lesions with enlarged folds at the greater curvature of the gastric body. Biopsy specimens of the lesions revealed poorly differentiated adenocarcinoma and signet ring cell carcinoma. The cancer was classified as stage IV with pancreatic invasion. Although NG with pangastritis is considered a high-risk factor for diffuse-type gastric carcinoma, the course of NG after eradication remains unknown. Careful histological assessment before eradication by endoscopic biopsy and close follow-up after eradication are therefore recommended, even in young patients.

The Prevalence of Liver Cytolysis in Children with Helicobacter pylori Infection

(1) Background: The relationship between Helicobacter pylori (H. pylori) infection and liver disease has been discussed for many years, but the association between the infection and liver cytolysis in children has been insufficiently explored. In our study, we evaluate this relationship in a pediatric population from the northeast of Romania. (2) Methods: A retrospective study of children with H. pylori infection and liver cytolysis was conducted on a group of 1757 children, admitted to a pediatric gastroenterology regional center in northeast Romania over 3 years. (3) Results: Liver cytolysis syndrome was present in 112 children of both sexes. Of the 112 children, 20 children (17.9%) also had H. pylori infection. In the statistical analysis, we noted a significant association between liver cytolysis syndrome and H. pylori infection (χ2; p < 0.001). (4) Conclusions: This relationship requires further in-depth studies that also consider certain parameters that may influence the results of these correlations. In addition, we point out the need for further analyses evaluating, in terms of the histopathological changes in each liver disease, the efficacy of H. pylori eradication.

Biomarker identification of chronic atrophic gastritis and its potential drug analysis

Background

Chronic atrophic gastritis (CAG) is the first step of gastric precancerous lesions, and the study of the pathogenesis of CAG is helpful for the prevention and treatment of gastric cancer(GC). The purpose of this study is to explore the potential biomarkers and therapeutic drugs of CAG through bioinformatics analysis.

Methods

The GSE11632 dataset was downloaded from Gene Expression Omnibus (GEO) database and the differentially expressed genes (DEGs) were obtained by using GEO2R online tool. We searched GeneCard and DisGeNET databases for genes related to CAG and used the overlapping genes as final DEGs for further functional enrichment analysis and Protein-protein Interaction (PPI) network analysis. Tissue-specific expressed genes were identified by BioGPS database. Cytoscape software was used to identify key hub genes and validated them in GSE27411 data sets. The upstream miRNAs of hub gene was predicted by TargetScan, miRDB and miRWalk. Finally, run the Connectivity Map (CMap) to identify new potential drugs for the treatment of CAG.

Results

A total of 430 differentially expressed mRNA were identified in this study, including 315 up-regulated genes and 115 down-regulated genes. After intersecting with CAG-related genes in GeneCard and DisGeNET databases, 42 DEGs were obtained. 24 DEGs were identified as tissue-specific expressed genes, most of which were expressed in stomach. GO and KEGG pathway analysis showed that DGEs was mainly enriched in digestion, IL-1 production, gastric acid secretion and so on. A total of 6 hub genes were generated by cytoHubba plug-in, among which ATP4A, CFTR and EPCAM had high diagnostic value. A total of 13 overlapping miRNA were predicted by 6 hub genes.

Conclusion

ATP4A, CFTR and EPCAM may be potential biomarkers of CAG. hsa-miR-185-5p-CFTR, hsa-miR-4644-CFTR and hsa-miR-4505-CFTR are potential RNA regulatory pathways to control the progression of CAG disease. Finally, amonafide, etoposide, mycophenolate-mofetil, cycloheximide and Emetine may be potential therapeutic drugs for CAG.

Alterations of Microorganisms in Tongue Coating of Gastric Precancerous Lesion Patients with a Damp Phlegm Pattern

Objective. In the research, the microbial changes in the tongue coating of patients with a damp phlegm pattern of gastric precancerous lesion (GPL) were investigated. Methods. This was a case-control study, in which 80 tongue coating samples were collected including 40 patients with a damp phlegm pattern of GPL, 20 patients with a nondamp phlegm pattern of GPL, and 20 healthy control people. The 16S rRNA microbiome technology was used to analyze the alterations of microorganisms in tongue coating of GPL patients with a damp phlegm pattern. Results. Microorganisms in the genus level were analyzed. Compared with the healthy control group, the relative abundance of 4 microorganisms (Solobacterium, Rothia, Oribacterium, and Alloprevotella) in the GPL group was significantly higher ( $P<0.05$ ). The relative abundance of 10 microorganisms (Terrisporobacter, Solobacterium, Porphyromonas, Parvimonas, Lactobacillus, Johnsonella, Gemella, Fusibacter, Azoarcus, and Acidothermus) in the GPL damp phlegm pattern group was significantly lower than that in the GPL nondamp phlegm pattern group ( $P<0.05$ ). In the comparison of phenotype “forms biofilms,” the relative abundance of microorganisms in the GPL group was significantly higher than that in the healthy control group ( $P<0.05$ ). In the comparison of phenotype “contains mobile elements,” the relative abundance of microorganisms in the GPL damp phlegm pattern group was significantly lower than that in the GPL nondamp phlegm pattern group ( $P<0.05$ ). In the comparison of microbial metabolic functions, the abundance ratio of “infectious diseases: bacterial” in the GPL group was significantly lower than that in the healthy control group ( $P<0.05$ ). The abundance ratio of the “excretory system” and “folding, sorting, and degradation” in the GPL group was significantly higher than that in the healthy control group ( $P<0.05$ ). Conclusions. Solobacterium may be a marker microorganism of the GPL damp phlegm pattern. The differential phenotype of microorganisms in tongue coating of the GPL damp tongue pattern is mainly reflected in “forms biofilms” and “contains mobile elements.”

SOX2 contributes to invasion and poor prognosis of gastric cancer: A meta-analysis

BACKGROUND

The sex-determining region Y-box 2 (SOX2) has been identified to be involved in tumor progression and prognosis in patients with gastric cancer (GC). However, its action is paradoxical. Thus, we conducted the first meta-analysis based on eligible studies to evaluate the clinical utility of SOX2 in GC only.

METHODS

A thorough electronic search was performed to collect eligible studies. The hazard ratios (HRs) or odds ratios (ORs) with 95% confidence intervals (CIs) were generated from included studies to assess the strength of the association between SOX2 and prognosis and clinicopathological characteristics in GC.

RESULTS

A total of 10 studies comprising 1321 patients with GC were identified for the meta-analysis. The pooled results revealed that high SOX2 expression was significantly associated with poor overall survival compared to low SOX2 expression (pooled HR = 1.485; 95% CI: 1.022-2.160; 𝑃 = .04). The statistical significance between SOX2 expression and overall survival was also established in univariate analysis (pooled HR = 1.606; 95% CI: 1.134-2.274; 𝑃 < .01), as well as recruitment time exceeding 2010 (pooled HR = 1.873; 95% CI: 1.041-3.371; 𝑃 = .04), follow-up time more than 5 years (pooled HR = 1.642; 95% CI: 1.066-2.527; 𝑃 = .02), and cutoff value of more than 5% of cells stained (pooled HR = 1.730; 95% CI: 1.162-2.577; 𝑃 < .01). Moreover, we verified that positive SOX2 expression was correlated with advanced tumor invasion depth (pooled OR = 0.494; 95% CI: 0.362-0.675; 𝑃 < .01) and positive vascular invasion (pooled OR = 1.515; 95% CI: 1.078-2.130; 𝑃 = .02).

CONCLUSION

SOX2 could not only be an independent prognostic marker in GC but might also be a novel target for cancer therapy.

Induction of Fibroblast Growth Factor Receptor 4 by Helicobacter pylori via Signal Transducer and Activator of Transcription 3 With a Feedforward Activation Loop Involving SRC Signaling in Gastric Cancer

BACKGROUND & AIMS

Helicobacter pylori (H pylori) infection is the main risk factor for gastric cancer. The role of fibroblast growth factor receptors (FGRFs) in H pylori-mediated gastric tumorigenesis remains largely unknown. This study investigated the molecular and mechanistic links between H pylori, inflammation, and FGFR4 in gastric cancer.

METHODS

Cell lines, human and mouse gastric tissue samples, and gastric organoids models were implemented. Infection with H pylori was performed using in vitro and in vivo models. Western blot, real-time quantitative reverse-transcription polymerase chain reaction, flow cytometry, immunofluorescence, immunohistochemistry, chromatin immunoprecipitation, and luciferase reporter assays were used for molecular, mechanistic, and functional studies.

RESULTS

Analysis of FGFR family members using The Cancer Genome Atlas data, followed by validation, indicated that FGFR4 messenger (m)RNA was the most significantly overexpressed member in human gastric cancer tissue samples (P < .001). We also detected high levels of Fgfr4 mRNA and protein in gastric dysplasia and adenocarcinoma lesions in mouse models. Infection with J166, 7.13, and PMSS1 cytotoxin-associated gene A (CagA)+ H pylori strains induced FGFR4 mRNA and protein expression in in vitro and in vivo models. This was associated with a concordant activation of signal transducer and activator of transcription 3 (STAT3). Analysis of the FGFR4 promoter suggested several putative binding sites for STAT3. Using chromatin immunoprecipitation assay and an FGFR-promoter luciferase reporter containing putative STAT3 binding sites and their mutants, we confirmed a direct functional binding of STAT3 on the FGFR4 promoter. Mechanistically, we also discovered a feedforward activation loop between FGFR4 and STAT3 where the fibroblast growth factor 19–FGFR4 axis played an essential role in activating STAT3 in a SRC proto-oncogene non-receptor tyrosine kinase dependent manner. Functionally, we found that FGFR4 protected against H pylori-induced DNA damage and cell death.

CONCLUSIONS

Our findings demonstrated a link between infection, inflammation, and FGFR4 activation, where a feedforward activation loop between FGFR4 and STAT3 is established via SRC proto-oncogene non-receptor tyrosine kinase in response to H pylori infection. Given the relevance of FGFR4 to the etiology and biology of gastric cancer, we propose FGFR4 as a druggable molecular vulnerability that can be tested in patients with gastric cancer.

Endoscopic scoring system for gastric atrophy and intestinal metaplasia: correlation with OLGA and OLGIM staging: a single-center prospective pilot study in Korea

BACKGROUND/AIMS

We aimed to develop an endoscopic scoring system to evaluate gastric atrophy and intestinal metaplasia using narrow-band imaging (NBI) and near focus mode (NFM) to compare endoscopic scores with the Operative link for gastritis assessment (OLGA) and the Operative link for gastric intestinal metaplasia assessment (OLGIM).

METHODS

A total of 51 patients who underwent diagnostic esophagogastroduodenoscopy were prospectively enrolled and endoscopic scoring using NBI and NFM was performed. Four areas (the lesser and greater curvatures of the antrum and the lesser and greater curvature side of the corpus) were observed and biopsies were taken. The degree of atrophy was scored from 0 to 2 according to the Kimura-Takemoto classification. The degree of intestinal metaplasia was scored from 0 to 4 according to the location and the extent of the intestinal metaplasia.

RESULTS

The correlation coefficient for atrophy between the endoscopic and histologic scores was 0.70 (95% CI: 0.52-0.81 p < .001) and for intestinal metaplasia, it was 0.75 (95% CI: 0.60-0.85; p < .001). For atrophic gastritis, an endoscopic score >1 correlated with OLGA stage III and IV with a sensitivity, specificity, positive predictive value, negative predictive value, and agreement of 88, 74, 75, 87, and 80.4%, respectively, and for intestinal metaplasia, an endoscopic score >1 correlated with high OLGIM stage III and IV with 100, 59, 69, 100, and 78.4%, respectively.

CONCLUSIONS

Endoscopic scoring for gastric atrophy and intestinal metaplasia using NBI-NFM likely correlates with histologic staging in Korea, a high-risk region for gastric cancer.

Microbial Proteins in Stomach Biopsies Associated with Gastritis, Ulcer, and Gastric Cancer

(1) Background: Gastric cancer (GC) is the fourth leading cause of cancer-related deaths worldwide. Helicobacter pylori infection is a major risk factor, but other microbial species may also be involved. In the context of an earlier proteomics study of serum and biopsies of patients with gastroduodenal diseases, we explored here a simplified microbiome in these biopsies (H. pylori, Acinetobacter baumannii, Escherichia coli, Fusobacterium nucleatum, Bacteroides fragilis) on the protein level. (2) Methods: A cohort of 75 patients was divided into groups with respect to the findings of the normal gastric mucosa (NGM) and gastroduodenal disorders such as gastritis, ulcer, and gastric cancer (GC). The H. pylori infection status was determined. The protein expression analysis of the biopsy samples was carried out using high-definition mass spectrometry of the tryptic digest (label-free data-independent quantification and statistical analysis). (3) Results: The total of 304 bacterial protein matches were detected based on two or more peptide hits. Significantly regulated microbial proteins like virulence factor type IV secretion system protein CagE from H. pylori were found with more abundance in gastritis than in GC or NGM. This finding could reflect the increased microbial involvement in mucosa inflammation in line with current hypotheses. Abundant proteins across species were heat shock proteins and elongation factors. (4) Conclusions: Next to the bulk of human proteins, a number of species-specific bacterial proteins were detected in stomach biopsies of patients with gastroduodenal diseases, some of which, like those expressed by the cag pathogenicity island, may provide gateways to disease prevention without antibacterial intervention in order to reduce antibiotic resistance.

The Roles of Immune Cells in Gastric Cancer: Anti-Cancer or Pro-Cancer?

Simple Summary

Gastric cancer is still one of the leading causes of death caused by cancer in developing countries. The emerging role of immunotherapy in cancer treatment has led to more research to elucidate the roles of essential immune cells in gastric cancer prognosis. We reviewed the roles of immune cells including T cells, B cells, dendritic cells, macrophages and natural killer cells in gastric cancer. Although the studies conducted on the roles of immune cells in gastric cancer pathogenesis produced conflicting results, understanding the roles of immune cells in gastric cancer will help us to harness them for application in immunotherapy for better prognosis and management of gastric cancer patients.

Abstract

Despite the fact that the incidence of gastric cancer has declined over the last decade, it is still the world’s leading cause of cancer-related death. The diagnosis of early gastric cancer is difficult, as symptoms of this cancer only manifest at a late stage of cancer progression. Thus, the prognosis of gastric cancer is poor, and the current treatment for improving patients’ outcomes involves the application of surgery and chemotherapy. Immunotherapy is one of the most recent therapies for gastric cancer, whereby the immune system of the host is programmed to combat cancer cells, and the therapy differs based upon the patient’s immune system. However, an understanding of the role of immune cells, namely the cell-mediated immune response and the humoral immune response, is pertinent for applications of immunotherapy. The roles of immune cells in the prognosis of gastric cancer have yielded conflicting results. This review discusses the roles of immune cells in gastric cancer pathogenesis, specifically, T cells, B cells, macrophages, natural killer cells, and dendritic cells, as well as the evidence presented thus far. Understanding how cancer cells interact with immune cells is of paramount importance in designing treatment options for gastric cancer immunotherapy.

The bacteria inside human cancer cells: Mainly as cancer promoters

The roles of the microbiome in human beings have become clearer with the development of next-generation sequencing techniques. Several pieces of evidence showed strong correlations between the microbiome and human health and disease, such as metabolic disorders, infectious diseases, digestive system diseases, and cancers. Among these diverse microbiomes, the role of bacteria in human cancers, especially in cancer cells, has received extensive attention. Latest studies found that bacteria widely existed in cancers, mainly in cancer cells and immune cells. In this review, we summarize the latest advances in understanding the role of bacteria in human cancer cells. We also discuss how bacteria are transported into cancer cells and their physiological significance in cancer progression. Finally, we present the prospect of bacterial therapy in cancer treatment.

Benefit-to-harm ratio and cost-effectiveness of government-recommended gastric cancer screening in China: A modeling study

Objective

Current guidelines recommend the gastric cancer risk score scale (GCRSS) for screening in gastric cancer (GC) high-risk populations in China. This study aimed to estimate the clinical benefits, harms, cost, and cost-effectiveness of the GCRSS screening strategy from a Chinese healthcare system perspective.

Materials and methods

Using a microsimulation model, we evaluated 7 screening scenarios of the GCRSS with varying starting ages. We simulated 100,000 individuals from the age of 20 for each screening scenario. The main outcomes included GC incidence reduction, number of cause-specific deaths, costs, quality-adjusted life year (QALY), incremental cost-effectiveness ratio (ICER), and benefit-to-harm ratio. Deterministic and probabilistic sensitivity analyses were done to explore the robustness of model findings.

Results

Screening with the GCRSS strategy at the age of 40 years (40-GCRSS) provided the greatest reduction of GC incidence by 70.6%, with 7,374 GC deaths averted per 100,000 individuals and the lowest benefit-to-harm ratio of 0.392. Compared with no screening or previous less costly strategy, at a willingness-to-pay (WTP) threshold of $37,655 per QALY, the 40-GCRSS strategy was cost-effective, with ICERs of $12,586 and $29,115 per QALY, respectively. Results were robust across univariate and probabilistic sensitivity analyses. The 40-GCRSS strategy showed a 0.856 probability of being cost-effective at a $37,655 per QALY WTP threshold.

Conclusions

The findings suggest that the GCRSS strategy is effective and cost-effective in reducing the GC disease burden in China from a Chinese healthcare system perspective. Screening from the age of 40 would be the optimal strategy.

Manpixiao Decoction Halted the Malignant Transformation of Precancerous Lesions of Gastric Cancer: From Network Prediction to In-Vivo Verification

Manpixiao decoction (MPX), a traditional Chinese medicine formula, is mainly used to improve the gastric mucosal pathology and stomach discomfort in patients with gastric precancerous lesions. Precancerous lesion of gastric cancer (PLGC) refers to intestinal metaplasia and/or dysplasia based on gastric mucosal atrophy. Effective prevention and treatment of PLGC is of great significance to reduce the incidence of gastric cancer. Because of the complexity of the etiology and pathogenesis of PLGC, there is no unified and effective treatment plan in western medicine. In recent years, traditional Chinese medicine has shown obvious advantages in the treatment of PLGC and the prevention of its further progression to gastric cancer, relying on its multi-approach and multi-target comprehensive intervention characteristics. This study is designed to examine the protective effect of MPX against PLGC and further to reveal the engaged mechanism via integrating network pharmacology and in vivo experimental evidence. Network pharmacology results demonstrated that inflammation, immune responses, and angiogenesis might be associated with the efficacy of MPX in the treatment of PLGC, in which the PI3K-Akt, cellular senescence, P53 and protein processing in endoplasmic reticulum were involved. Then, we established a rat model of PLGC using a combination of N-methyl-N′-nitro-N-nitrosoguanidine (MNNG), sodium salicylate, irregular fasting, and ranitidine, and observed the effects after MPX treatment. Our result showed that MPX improved the pathological condition of gastric mucosa in PLGC rats and reduced the incidence of gastric cancer. Next, the analysis of serum inflammatory cytokines showed that MPX reduced the inflammation-related cytokines (such as IL-1α, IL-7, CSF-1, and CSF-3) in the serum. Additionally, MPX also had a regulation effect on the “protein/protein phosphorylation-signaling pathway” network in the core region of the PLGC rats. It is showed that MPX can inhibit the phosphorylation of PI3K-AKT, and downregulates the EGFR, β-catenin, and N-cadherin protein levels. These results indicate that MPX halted the PLGC progression through inhibiting EGFR-PI3K-AKT related epithelial-mesenchymal transition process.

Decreasing Incidence of Gastric Cancer with Increasing Time after Helicobacter pylori Treatment: A Nationwide Population-Based Cohort Study

Background: Treatment of Helicobacter pylori (HP) has been shown to reduce the risk of gastric cancer (GC) development. However, previous studies have focused on patients at high risk of GC. This study aimed to assess the effect of HP treatment on the incidence of GC in the general population. Materials and Methods: Medical records were obtained from the Common Data Model-converted sample Cohort of the National Health Insurance Service of Korea (NHIS-CDM). The target cohort included those who had been prescribed HP treatment and the comparator cohort included those who had not. The association between HP treatment and the risk of GC development was assessed using the Cox proportional hazard model. The incidences of GC according to the period after HP treatment in different age groups were analyzed using proportional trend tests. Results: After large-scale 1:4 propensity score matching, 2735 and 5328 individuals were included in the target and comparator cohorts, respectively. During the median follow-up of 6.5 years, the GC incidence was lower in the HP treatment cohort than in the comparator cohort, but this was statistically insignificant (hazard ratio [HR]: 0.76; 95% confidence interval [CI]: 0.50−1.13; p-value = 0.19). This trend was also observed among the older age (≥65 years, HR: 0.87; 95% CI: 0.44−1.68; p-value = 0.69) and male cohorts (HR: 0.82; 95% CI: 0.51−1.27; p-value = 0.38). Among 58,684 individuals who were treated for HP from the whole NHIS-CDM cohort, the incidence of GC consistently decreased over time and showed a marked decrease with increasing age (p for trend < 0.05). Conclusions: In all age groups of the general population, HP treatment could be recommended to reduce the risk of GC.

Comparison of the diagnostic accuracy of the updated Sydney system and single biopsy

BACKGROUND

Updated Sydney system (USS) recommends taking biopsies from certain areas of the stomach for the diagnosis of precancerous lesions associated with Helicobacter pylori. Our aim was to evaluate the contribution of each of the biopsy sites to the diagnosis.

METHODS

This prospective study included 97 patients aged 40 and over with dyspeptic complaints. Biopsies were taken from five regions: the lesser curvature of the antrum (LCA), the lesser curvature of the corpus (LCC), incisura angularis (IA), the greater curvature of the antrum (GCA), and the greater curvature of the corpus (GCC). Biopsy specimens were stained with hematoxylin-eosin stain, periodic acid Schiff-alcian blue, and Giemsa histochemical stain and evaluated according to the Sydney classification.

RESULTS

Thirty-seven (38%) patients were positive for H. pylori in at least one biopsy site. Atrophic gastritis without intestinal metaplasia (IM) was found in 17 (17.5%) of the patients (6.2% in IA, 5.2% in each of LCA, GCA, and LCC, and 2% in GCC). The prevalence of atrophic gastritis with IM was 42.3% (21.6% in LCA, 20.6% in GCA, 20.6% in IA, 14.4% in LCC, and 5.2% in GCC). Endoscopic follow-up was planned in 21 (22%) patients due to the presence of extensive atrophy or incomplete IM. If a single biopsy of the LCA or a biopsy of both LCA and GCA was taken, endoscopic follow-up would have been missed in 12 (57%) or 6 (29%) patients, respectively.

CONCLUSION

Taking biopsies in accordance with the USS had higher sensitivity in detecting atrophic gastritis with or without IM compared to single biopsy. One or two biopsies is not sufficient to identify patients for whom endoscopic follow-up is recommended.

Assessment of Serum Pepsinogens with and without Co-Testing with Gastrin-17 in Gastric Cancer Risk Assessment-Results from the GISTAR Pilot Study

Introduction−−Serum pepsinogen tests for gastric cancer screening have been debated for decades. We assessed the performance of two pepsinogen assays with or without gastrin-17 for the detection of different precancerous lesions alone or as a composite endpoint in a Latvian cohort. Methods−−Within the intervention arm of the GISTAR population-based study, participants with abnormal pepsinogen values by ELISA or latex-agglutination tests, or abnormal gastrin-17 by ELISA and a subset of subjects with all normal biomarker values were referred for upper endoscopy with biopsies. Performance of biomarkers, corrected by verification bias, to detect five composite outcomes based on atrophy, intestinal metaplasia, dysplasia or cancer was explored. Results−−Data from 1045 subjects were analysed, of those 273 with normal biomarker results. Both pepsinogen assays showed high specificity (>93%) but poor sensitivity (range: 18.4−31.1%) that slightly improved when lesions were restricted to corpus location (40.5%) but decreased when dysplasia and prevalent cancer cases were included (23.8%). Adding gastrin-17 detection, sensitivity reached 33−45% while specificity decreased (range: 61.1−62%) and referral rate for upper endoscopy increased to 38.6%. Conclusions−−Low sensitivity of pepsinogen assays is a limiting factor for their use in population-based primary gastric cancer screening, however their high specificity could be useful for triage.

Clinical outcomes of metachronous recurrence of gastric epithelial neoplasia based on Helicobacter pylori infection status and microsatellite stability

BACKGROUND/AIMS

Helicobacter pylori eradication may prevent the recurrence of gastric epithelial neoplasia after endoscopic treatment. However, H. pylori eradication therapy is unlikely to prevent gastric cancer. This study determined the longterm results and clinical outcomes of patients with gastric epithelial neoplasia based on H. pylori infection status and microsatellite stability (MSS).

METHODS

Patients diagnosed with gastric epithelial neoplasia who underwent an endoscopic mucosal resection or submucosal dissection between 2004 and 2010 were included in this retrospective study. During the follow-up period (range, 4 to 14 years), disease recurrence was monitored, and tissue examinations were conducted for seven sets of microsatellite loci initially linked to the tumour suppressor gene locus. When H. pylori infection was identified, patients underwent eradication therapy.

RESULTS

The patients (n = 120) were divided into three groups: H. pylori-negative with MSS, H. pylori-positive with MSS, and microsatellite instability (MSI). After H. pylori eradication, the rate of metachronous recurrence was significantly different in the MSI (28.2%) and MSS groups (3.7%, p < 0.01). The mean duration of recurrence was 77 months (range, 24 to 139) in the MSI group. There was no recurrence after eradication therapy in patients who were positive for H. pylori in the MSS group.

CONCLUSION

H. pylori eradication could help prevent gastric cancer recurrence in patients with stable microsatellite loci. Careful, long-term monitoring is required in patients with unstable microsatellite loci.

Clinical Benefit and Cost Effectiveness of Risk-Stratified Gastric Cancer Screening Strategies in China: A Modeling Study

BACKGROUND AND OBJECTIVE

A new gastric cancer screening scoring system (NGCS) strategy was recommended for the early gastric cancer (GC) screening process in China. The current study aimed to assess the clinical benefits and the cost effectiveness of the NGCS strategy in GC high-risk areas of China from a societal perspective.

METHODS

A Markov microsimulation model was developed to evaluate 30 alternative screening strategies with varying initiation age, including the NGCS strategy, the modified NGCS strategy, and the endoscopic screening strategy with various screening intervals. The primary outcomes included GC mortality, number of endoscopies, quality-adjusted life-years (QALYs), costs, and incremental cost-effectiveness ratios (ICERs). Cost estimates were reported in 2021 USD (US$) and both costs and benefits were discounted at 5% annually. Deterministic and probabilistic sensitivity analyses were performed to evaluate model uncertainty.

RESULTS

Screening with the NGCS strategy from age 40 years (40-NGCS) reduced the GC incidence by 86.4%, which provided the greatest benefit across strategies. Compared with all strategies, at a willingness-to pay threshold of US$17,922 per QALY, the 40-NGCS strategy was a leading cost-effective strategy, with an ICER of US$15,668 per QALY. Results were robust in univariate and probabilistic sensitivity analyses. The probability of the 40-NGCS strategy being cost effective was 0.863.

CONCLUSIONS

The 40-NGCS strategy was an effective and cost-effective strategy to reduce GC incidence and mortality in China. The findings provide important evidence for decision makers to formulate and optimize targeted approaches for GC prevention and control policies in China.

The Difference of Endoscopic and Histologic Improvements of Atrophic Gastritis and Intestinal Metaplasia After Helicobacter pylori Eradication

BACKGROUND/AIMS

Helicobacter pylori (H. pylori) is an important risk factor of atrophic gastritis (AG), intestinal metaplasia (IM), and gastric cancer (GC). However, no report to date has described the endoscopic improvement of AG and IM after H. pylori eradication. Thus, the aim of this study was to evaluate the improvement of AG and IM after H. pylori eradication using endoscopic and histologic analyses.

METHODS

A total of 380 subjects were prospectively enrolled for up to 12 years and grouped by their H. pylori infection status: negative, non-eradicated, and eradicated. Endoscopic and histologic analyses of AG and IM were performed in the antrum and the corpus, by annual follow-up endoscopy.

RESULTS

Endoscopic AG and IM in the antrum and corpus in the eradicated group improved compared to that in the non-eradicated group (AG, P = 0.002 and P = 0.005; IM, P = 0.038 and P = 0.048, respectively). Histologic AG and IM in the antrum and corpus in the eradicated group also improved compared to that in the non-eradicated group (all P < 0.001). Time taken to the endoscopic improvement of AG and IM after H. pylori eradication was significantly longer than time taken to the histologic improvement in the antrum and corpus (AG in antrum: 3.47 ± 2.60 vs. 2.34 ± 1.71 years, P = 0.004; AG in corpus: 3.19 ± 2.30 vs. 1.87 ± 1.48 years, P = 0.002; IM in antrum: 4.40 ± 2.38 vs. 3.62 ± 2.35 years, P = 0.043; and IM in corpus: 4.82 ± 1.08 vs. 3.61 ± 2.22 years, P = 0.007, respectively).

CONCLUSIONS

Both endoscopic and histologic improvements of AG and IM were observed after H. pylori eradication, while endoscopic improvement took significantly longer time than histologic improvement.

Inflammation and Gastric Cancer

Gastric cancer remains a major killer globally, although its incidence has declined over the past century. It is the fifth most common cancer and the third most common reason for cancer-related deaths worldwide. Gastric cancer is the outcome of a complex interaction between environmental, host genetic, and microbial factors. There is significant evidence supporting the association between chronic inflammation and the onset of cancer. This association is particularly robust for gastrointestinal cancers in which microbial pathogens are responsible for the chronic inflammation that can be a triggering factor for the onset of those cancers. Helicobacter pylori is the most prominent example since it is the most widespread infection, affecting nearly half of the world’s population. It is well-known to be responsible for inducing chronic gastric inflammation progressing to atrophy, metaplasia, dysplasia, and eventually, gastric cancer. This review provides an overview of the association of the factors playing a role in chronic inflammation; the bacterial characteristics which are responsible for the colonization, persistence in the stomach, and triggering of inflammation; the microbiome involved in the chronic inflammation process; and the host factors that have a role in determining whether gastritis progresses to gastric cancer. Understanding these interconnections may improve our ability to prevent gastric cancer development and enhance our understanding of existing cases.

Differences in the Association Between Modifiable Lifestyle Factors and Gastric Precancerous Lesions Among Mongolians and Han Chinese

Background

There has been a paucity of evidence examining whether preventable behavioral risk factors led to ethnic differences of gastric precancerous lesions (GPL). We aimed to investigate the ethnic disparity of associations between GPL and lifestyle factors in Mongolian and Han Chinese populations.

Methods

The study included participants aged 36-75 years enrolled in the Cancer Screening Program during 2016-2017 in Hohhot and Tongliao City, Inner Mongolia. GPL was defined as the gross cascading events (i.e., gastric ulcer, atrophic gastritis, intestinal metaplasia, and dysplasia) that preceded gastric cancer.

Results

A total of 61638 participants were included, of whom 6863(11·1%) were Mongolians. Alcohol consumption was positively associated with GPL risk in both ethnic groups, but the magnitude was greater in Mongolians (odds ratio (OR) 6·91, 95%CI 5·82-8·28) than in Han Chinese (OR 5·64, 95%CI 5·27-6·04), corresponding to a higher population attributable fraction (PAF) for Mongolians (53·18% vs 43·71%). Besides, the strength of the positive association between physical inactivity and GPL risk was greater among Mongolians (OR 2·02, 95%CI 1·70-2·41; OR 1·09, 95%CI 1·02-1·17 among Han Chinese) with a higher PAF. Smoking was strongly associated with GPL risk in both ethnic groups as well, but the association was more prominent among Han Chinese (OR 5·24 (1·70-2·41) for <10 cigarettes/d, 8·19 (7·48-8·97) for 11-20 cigarettes/d, 7·07 (6·40-7·81) for ≥21 cigarettes/d; the corresponding ORs were 2·96 (2·19-4·00), 6·22 (5·04-7·68), and 7·03 (5·45-9·08) among Mongolians). Lastly, our findings revealed that a significant correlation between insufficient fruits and vegetable consumption and GPL risk was only found among Mongolians (OR 1·27, 95%CI 1·04-1·56).

Conclusions

Our result suggested that high-risk lifestyle factors should be reduced, particularly in Mongolians. Further studies are needed to elucidate the underlying mechanisms and to reduce health disparities in underserved ethnic groups.

Animal Models and Helicobacter pylori Infection

Helicobacter pylori colonize the gastric mucosa of at least half of the world’s population. Persistent infection is associated with the development of gastritis, peptic ulcer disease, and an increased risk of gastric cancer and gastric-mucosa-associated lymphoid tissue (MALT) lymphoma. In vivo studies using several animal models have provided crucial evidence for understanding the pathophysiology of H. pylori-associated complications. Numerous animal models, such as Mongolian gerbils, transgenic mouse models, guinea pigs, and other animals, including non-human primates, are being widely used due to their persistent association in causing gastric complications. However, finding suitable animal models for in vivo experimentation to understand the pathophysiology of gastric cancer and MALT lymphoma is a complicated task. In this review, we summarized the most appropriate and latest information in the scientific literature to understand the role and importance of H. pylori infection animal models.

Efficacy and safety of Elian Granules in treating chronic atrophic gastritis: study protocol for a randomized, double-blind, placebo-controlled, multicenter clinical trial

Background

Multifocal atrophic gastritis and intestinal metaplasia are considered to be important links in the gastric precancerous cascade. However, there are no specific drugs for these conditions. Although many studies have shown that traditional Chinese medicine is effective with no serious side effects, these studies have not been scientifically rigorous trials. Our aim is to design a high-quality trial for a Chinese patent medicine, Elian Granules, to investigate its efficacy and safety in treating patients with chronic atrophic gastritis with or without intestinal metaplasia.

Methods

This is a phase II, randomized, double-blind, placebo-controlled, multicenter clinical trial. A total of 240 participants will be assigned to a treatment or placebo control group in a 1:1 ratio. The experimental drug or placebo will be taken with boiling water, two small bags (24.2 g) each time, twice a day, half an hour after a meal, for 24 weeks. The primary outcome is the observation of histological changes in the gastric mucosa of patients with atrophic gastritis with or without intestinal metaplasia after 6 months based on the OLGA/OLGIM staging systems. The secondary outcomes include the assessment of dyspepsia and quality of life based on the dyspepsia symptom score and the quality-of-life scale.

Discussion

This study is designed to evaluate the efficacy and safety of Elian Granules in a randomized, double-blind, placebo-controlled, multicenter manner. This trial may not only provide evidence for a phase III clinical trial, but also an alternative option for the treatment of chronic atrophic gastritis (CAG).

Trial registration

Registry Platform For Evidence-Based Traditional Chinese Medicine ChiMCTR2000003929. Registered on 13 September 2020

Artificial Intelligence for Upper Gastrointestinal Endoscopy: A Roadmap from Technology Development to Clinical Practice

Stomach cancer is the third deadliest type of cancer in the world (0.86 million deaths in 2017). In 2035, a 20% increase will be observed both in incidence and mortality due to demographic effects if no interventions are foreseen. Upper GI endoscopy (UGIE) plays a paramount role in early diagnosis and, therefore, improved survival rates. On the other hand, human and technical factors can contribute to misdiagnosis while performing UGIE. In this scenario, artificial intelligence (AI) has recently shown its potential in compensating for the pitfalls of UGIE, by leveraging deep learning architectures able to efficiently recognize endoscopic patterns from UGIE video data. This work presents a review of the current state-of-the-art algorithms in the application of AI to gastroscopy. It focuses specifically on the threefold tasks of assuring exam completeness (i.e., detecting the presence of blind spots) and assisting in the detection and characterization of clinical findings, both gastric precancerous conditions and neoplastic lesion changes. Early and promising results have already been obtained using well-known deep learning architectures for computer vision, but many algorithmic challenges remain in achieving the vision of AI-assisted UGIE. Future challenges in the roadmap for the effective integration of AI tools within the UGIE clinical practice are discussed, namely the adoption of more robust deep learning architectures and methods able to embed domain knowledge into image/video classifiers as well as the availability of large, annotated datasets.

Self-Renewal and Cancers of the Gastric Epithelium: An Update and the Role of the Lectin TFF1 as an Antral Tumor Suppressor

In 2020, gastric cancer was the fourth leading cause of cancer deaths globally. About 90% of gastric cancers are sporadic and the vast majority are correlated with Helicobacter pylori infection; whereas familial clustering is observed in about 10% of cases. Gastric cancer is now considered to be a disease originating from dysregulated self-renewal of the gastric glands in the setting of an inflammatory environment. The human stomach contains two types of gastric units, which show bi-directional self-renewal from a complex variety of stem cells. This review focuses on recent progress concerning the characterization of the different stem cell populations and the mainly mesenchymal signals triggering their stepwise differentiation as well as the genesis of pre-cancerous lesions and carcinogenesis. Furthermore, a model is presented (Lectin-triggered Receptor Blocking Hypothesis) explaining the role of the lectin TFF1 as an antral tumor suppressor possibly regulating Lgr5⁺ antral stem cells in a paracrine or maybe autocrine fashion, with neighboring antral gland cells having a role as niche cells.

Association of Progranulin Gene Expression from Dyspeptic Patients with Virulent Helicobacter pylori Strains; In Vivo Model

(1) Background: Gastric cancer, the fourth most common cause of death from tumors in the world, is closely associated with Helicobacter pylori. Timely diagnosis, therefore, is essential to achieve a higher survival rate. In Chile, deaths from gastric cancer are high, mainly due to late diagnosis. Progranulin has reflected the evolution of some cancers, but has been poorly studied in gastric lesions. Aiming to understand the role of progranulin in H. pylori infection and its evolution in development of gastric lesions, we evaluated the genic expression of progranulin in gastric tissue from infected and non-infected patients, comparing it according to the epithelial status and virulence of H. pylori strains. (2) Methods: The genic expression of progranulin by q-PCR was quantified in gastric biopsies from Chilean dyspeptic patients (n = 75) and individuals who were uninfected (n = 75) by H. pylori, after receiving prior informed consent. Bacteria were grown on a medium Columbia agar with equine-blood 7%, antibiotics (Dent 2%, Oxoid^TM), in a microaerophilic environment, and genetically characterized for the ureC, vacA, cagA, and iceA genes by PCR. The status of the tissue was determined by endoscopic observation. (3) Results: Minor progranulin expression was detected in atrophic tissue, with a sharp drop in the tissue colonized by H. pylori that carried greater virulence, VacAs1m1⁺CagA⁺IceA1⁺. (4) Conclusions: Progranulin shows a differential behavior according to the lesions and virulence of H. pylori, affecting the response of progranulin against gastric inflammation.

Association between Vitamin B12 and Risk of Gastric Cancer: A Systematic Review and Meta-Analysis of Epidemiological Studies

Epidemiological studies focusing on the association between vitamin B₁₂ and gastric cancer risk reported inconsistent findings. We conducted a systematic review and meta-analysis to assess the relationship. PubMed (Medline), Web of science and EMBASE databases were systematically searched. A total of nine studies involving 3,494 cases of with gastric cancer and 611,638 participants were included. The result showed that there is no significant association between vitamin B₁₂ intake and the risk of gastric cancer (OR = 0.88, 95% CI: 0.69-1.12, P = 0.303). Nevertheless, high intake of vitamin B₁₂ might decrease the risk of gastric cancer in Helicobacter pylori (Hp)-negative people (OR = 0.83, 95% CI: 0.62-0.99, P = 0.044), but increase the cancer risk in Hp-positive populations (OR = 1.66, 95% CI: 1.27-2.16, P = 10^-4). Additionally, further analysis indicated that excessive vitamin B₁₂ might increase the risk of non-cardia gastric cancer (OR = 1.15, 95% CI: 1.01-1.33, P = 0.006). A negative association between vitamin B₁₂ intake and gastric cancer risk was found in nonsmokers (OR = 0.83, 95% CI: 0.71-0.96, P = 0.012) but not in smokers (OR = 1.08, 95% CI: 0.71-1.47, P = 0.619). In conclusion, although we found no convincing evidence that vitamin B₁₂ intake is associated with the risk of gastric cancer, it is important to maintain the relative stability of vitamin B₁₂ for people with Hp infection.

Factors Associated with False Negative Results in Serum Pepsinogen Testing for Precancerous Gastric Lesions in a European Population in the GISTAR Study

The accuracy of plasma pepsinogen (Pg) as a marker for precancerous gastric lesions (PGL) has shown variable results. We aimed to identify factors associated with false negative (FN) cases in Pg testing and to adjust cut-off values for these factors in order to improve Pg yield. Plasma Pg was measured and upper endoscopy with biopsy was performed within the "Multicentric randomized study of Helicobacter pylori eradication and pepsinogen testing for prevention of gastric cancer mortality: the GISTAR study". A multivariable logistic model was built for FN and multiple factors. Values of Pg were compared and sensitivity and specificity were calculated using pre-existing Pg cut-offs for factors showing strong associations with FN. New cut-offs were calculated for factors that showed substantially lower sensitivity. Of 1210 participants, 364 (30.1%) had histologically confirmed PGL, of which 160 (44.0%) were FN. Current smokers, men, and H. pylori positives were more likely FN. Smoking in H. pylori negatives was associated with a higher Pg I/II ratio and substantially lower sensitivity of Pg testing than in other groups. Adjusting Pg cut-offs for current smokers by H. pylori presence improved sensitivity for detecting PGL in this group. Our study suggests that adjusting Pg cut-offs for current smokers by H. pylori status could improve Pg test performance.

Mushroom-brush transitional conformation of mucus-inert PEG coating improves co-delivery of oral liposome for intestinal metaplasia therapy

The blocking of gastric mucosal intestinal metaplasia (IM) has been considered to be the pivotal method to control the occurrence of gastric cancer. However, there is still a lack of effective therapeutic agent. Here, we developed mucus-penetrating liposome system by covering surface with polyethylene glycol (PEG) chains (hydrophilic and electroneutral mucus-inert material) to co-delivery candidate drugs combination. Then studied the impact on the transmucus performance of different conformations, which were constructed by controlling the density of PEG chains on the surface. The results showed that the particle size of 5%PEG-Lip was less than 120 nm, the polydispersity index was less than 0.3, and the surface potential tended to be neutral. The D value (long chain spacing) of 5% PEG-Lip was 3.25 nm, which was close to the R_F value (diameter of spherical PEG long chain group without external force interference) of 3.44 nm, and the L value (extended length) was slightly larger than 3.44 nm. In this case, PEG showed mushroom-brush transitional conformation on the surface of liposomes. This conformation was not only promoted stable delivery, but also shielded the capture of mucus more favorably, leading to a more unrestricted transportation in mucus. The further in vivo experimental results demonstrated the rapid distribution of liposomes, which gradually appeared both in the superficial and deep glandular of mucosa and gland cells at 1 h and absorbed into the cell cytoplasm at 6 h. The 5% PEG-Lip with the mushroom-brush transitional configuration recalled abnormal organ index and improved inflammation and intestinal metaplasia. The modified PEG conformation assay presented here was more suitable for liposomes. This PEG-modified liposome system has potential of mucus-penetrating and provides a strategy for local treatment of gastric mucosal intestinal metaplasia.

Usefulness of artificial intelligence in early gastric cancer

Gastric cancer (GC) is a major cancer worldwide, with high mortality and morbidity. Endoscopy, important for the early detection of GC, requires trained skills, high-quality technologies, surveillance and screening programs. Early diagnosis allows a better prognosis, through surgical or curative endoscopic therapy. Magnified endoscopy with virtual chromoendoscopy remarkably improve the detection of early gastric cancer (EGC) when endoscopy is performed by expert endoscopists. Artificial intelligence (AI) has also been introduced to GC diagnostics to increase diagnostic efficiency. AI improves the early detection of gastric lesions because it supports the non-expert and experienced endoscopist in defining the margins of the tumor and the depth of infiltration. AI increases the detection rate of EGC, reduces the rate of missing tumors, and characterizes EGCs, allowing clinicians to make the best therapeutic decision, that is, one that ensures curability. AI has had a remarkable evolution in medicine in recent years, moving from the research phase to clinical practice. In addition, the diagnosis of GC has markedly progressed. We predict that AI will allow great evolution in the diagnosis and treatment of EGC by overcoming the variability in performance that is currently a limitation of chromoendoscopy.

The role of bile acids in carcinogenesis

Bile acids are soluble derivatives of cholesterol produced in the liver that subsequently undergo bacterial transformation yielding a diverse array of metabolites. The bulk of bile acid synthesis takes place in the liver yielding primary bile acids; however, other tissues have also the capacity to generate bile acids (e.g. ovaries). Hepatic bile acids are then transported to bile and are subsequently released into the intestines. In the large intestine, a fraction of primary bile acids is converted to secondary bile acids by gut bacteria. The majority of the intestinal bile acids undergo reuptake and return to the liver. A small fraction of secondary and primary bile acids remains in the circulation and exert receptor-mediated and pure chemical effects (e.g. acidic bile in oesophageal cancer) on cancer cells. In this review, we assess how changes to bile acid biosynthesis, bile acid flux and local bile acid concentration modulate the behavior of different cancers. Here, we present in-depth the involvement of bile acids in oesophageal, gastric, hepatocellular, pancreatic, colorectal, breast, prostate, ovarian cancer. Previous studies often used bile acids in supraphysiological concentration, sometimes in concentrations 1000 times higher than the highest reported tissue or serum concentrations likely eliciting unspecific effects, a practice that we advocate against in this review. Furthermore, we show that, although bile acids were classically considered as pro-carcinogenic agents (e.g. oesophageal cancer), the dogma that switch, as lower concentrations of bile acids that correspond to their serum or tissue reference concentration possess anticancer activity in a subset of cancers. Differences in the response of cancers to bile acids lie in the differential expression of bile acid receptors between cancers (e.g. FXR vs. TGR5). UDCA, a bile acid that is sold as a generic medication against cholestasis or biliary surge, and its conjugates were identified with almost purely anticancer features suggesting a possibility for drug repurposing. Taken together, bile acids were considered as tumor inducers or tumor promoter molecules; nevertheless, in certain cancers, like breast cancer, bile acids in their reference concentrations may act as tumor suppressors suggesting a Janus-faced nature of bile acids in carcinogenesis.

Performance status of targeted biopsy alone versus Sydney protocol by non-NBI expert gastroenterologist in gastric intestinal metaplasia diagnosis

Background and study aims  According to a recent guideline, patients with gastric intestinal metaplasia (GIM) should have at least five biopsies performed under the Sydney protocol to evaluate for risk of extensive GIM. However, only narrow-band imaging (NBI)-targeted biopsy may be adequate to diagnose extensive GIM. Patients and methods  A cross-sectional study was conducted between November 2019 and October 2020. Patients with histology-proven GIM were enrolled. All patients underwent standard esophagogastroduodenoscopy performed by a gastroenterology trainee. The performing endoscopists took biopsies from either a suspected GIM area (NBI-targeted biopsy) or randomly (if negative for GIM read by NBI) to complete five areas of the stomach as per the Sydney protocol. The gold standard for GIM diagnosis was pathology read by two gastrointestinal pathologists with unanimous agreement. Results  A total of 95 patients with GIM were enrolled and 50 (52.6%) were men with a mean age of 64 years. Extensive GIM was diagnosed in 43 patients (45.3%). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of NBI-targeted biopsy vs. the Sydney protocol were 88.4% vs.100 %, 90.3% vs. 90.3%, 88.4% vs. 89.6%, 90.3% vs. 100%, and 89.5% vs. 94.7%, respectively. The number of specimens from NBI-targeted biopsy was significantly lower than that from Sydney protocol (311vs.475, P  < 0.001). Conclusions  Both NBI-targeted biopsy and Sydney protocol by a gastroenterologist who was not an expert in NBI and who has experience with diagnosis of at least 60 cases of GIM provided an NPV higher than 90%. Thus, targeted biopsy alone with NBI, which requires fewer specimens, is an alternative option for extensive GIM diagnosis.

Endoscopic resection for early gastric cancer: Towards a global understanding

Gastric cancer is widespread globally, and disease diagnosis is accompanied by high mortality and morbidity rates. However, prognoses and survivability have improved following implementation of surveillance and screening programs, which have led to earlier diagnoses. Indeed, early diagnosis itself supports increased surgical curability, which is the main treatment goal and guides therapeutic choice. The most recent Japanese guidelines for endoscopic submucosal dissection and endoscopic mucosal resection for early gastric cancer consider the degree of endoscopic curability in relation to the characteristics of the gastric lesions. In clinical practice, the management approach for both prevention and treatment should be similar to that of colon lesions; however, unlike the established practices for colorectal cancer, the diagnostic and therapeutic pathways are not shared nor widespread for gastric cancer. Ultimately, this negatively impacts the opportunity to perform an endoscopic resection with curative intent.

Usefulness of optical enhancement endoscopy combined with magnification to improve detection of intestinal metaplasia in the stomach

Background and study aims  The light blue crest observed in narrow band imaging endoscopy has high diagnostic accuracy for diagnosis of gastric intestinal metaplasia (GIM). The objective of this prospective study was to evaluate the diagnostic accuracy of magnifying i-scan optical enhancement (OE) imaging for diagnosing the LBC sign in patients with different levels of risk for gastric cancer in a Mexican clinical practice. Patients and methods  Patients with a history of peptic ulcer and symptoms of dyspepsia or gastroesophageal reflux disease were enrolled. Diagnosis of GIM was made at the predetermined anatomical location and white light endoscopy and i-scan OE Mode 1 were captured at the two predetermined biopsy sites (antrum and pyloric regions). Results  A total of 328 patients were enrolled in this study. Overall GIM prevalence was 33.8 %. The GIM distribution was 95.4 % in the antrum and 40.5 % in the corpus. According to the Operative Link on Gastritis/Intestinal-Metaplasia Assessment staging system, only two patients (1.9 %) were classified with high-risk stage disease. Sensitivity, specificity, positive​ and negative predictive values, positive and negative likelihood ratios, and accuracy of both methods (95 % C. I.) were 0.50 (0.41-0.60), 0.55 (0.48-0.62), 0.36 (0.31-0.42), 0.68 (0.63-0.73), 1.12 (0.9-1.4), 0.9 (0.7-1.1), and 0.53 (0.43-0.60) for WLE, and 0.96 (0.90-0.99), 0.91 (0.86-0.94), 0.84 (0.78-0.89), 0.98 (0.94-0.99), 10.4 (6.8-16), 0.05 (0.02-0.12), and 0.93 (0.89-0.95), respectively. The kappa concordance was 0.67 and the reliability coefficient was 0.7407 for interobserver variability. Conclusions  Our study demonstrated the high performance of magnifying i-scan OE imaging for endoscopic diagnosis of GIM in Mexican patients.

Morphogen Signals Shaping the Gastric Glands in Health and Disease

The adult gastric mucosa is characterised by deep invaginations of the epithelium called glands. These tissue architectural elements are maintained with the contribution of morphogen signals. Morphogens are expressed in specific areas of the tissue, and their diffusion generates gradients in the microenvironment. Cells at different positions in the gland sense a specific combination of signals that instruct them to differentiate, proliferate, regenerate, or migrate. Differentiated cells perform specific functions involved in digestion, such as the production of protective mucus and the secretion of digestive enzymes or gastric acid. Biopsies from gastric precancerous conditions usually display tissue aberrations and change the shape of the glands. Alteration of the morphogen signalling microenvironment is likely to underlie those conditions. Furthermore, genes involved in morphogen signalling pathways are found to be frequently mutated in gastric cancer. We summarise the most recent findings regarding alterations of morphogen signalling during gastric carcinogenesis, and we highlight the new stem cell technologies that are improving our understanding of the regulation of human tissue shape.

Confocal Laser Endomicroscopy Can Improve the Diagnosis Rate and Range Assessment of Patients With Conflicting Chronic Atrophic Gastritis Results of White Light Endoscopic and Pathological Diagnosis

Background and Aims

Chronic atrophic gastritis (CAG) is closely related to the development of gastric cancer. However, the diagnostic accuracy of white light endoscopy (WLE) biopsy for CAG is poor. The diagnostic role and efficacy of confocal laser endomicroscopy (CLE) in CAG missed under WLE biopsy remain unclear.

Methods

This study is a single-center prospective study that included 21 patients from 1,349 patients who underwent WLE and biopsy and whose WLE results confirmed CAG, but pathological results did not. Then, all these patients received CLE examination and underwent targeted biopsies and five-point standard biopsies. The sensitivity, specificity, and accuracy of CLE diagnosis and targeted biopsy were analyzed.

Results

The pathological results of five-point standard biopsies in 21 patients confirmed CAG, and 17 patients (81.0%) were confirmed to have intestinal metaplasia (IM). According to the image diagnosis of CLE, there were 19 cases (90.5%) of CAG and 14 cases (66.7%) of IM among these 21 patients. According to the targeted biopsy of CLE, 17 cases (81.0%) of CAG and 14 cases (66.7%) of IM were diagnosed. There was no significant difference between CLE image diagnosis and five-point standard biopsies in terms of atrophy severity score (p = 0.927), IM severity score (p = 0.250), atrophy scope score (p = 0.781), and IM scope score (p = 0.195). For CAG, the sensitivity and accuracy of CLE image diagnosis were higher than those of CLE targeted biopsies (90.5% vs. 81.0%, p = 0.331), but for IM, the diagnosis was the same.

Conclusions

CLE can improve the diagnosis rate of CAG and can increase the comprehensive assessment of the scope and severity of CAG.

Gastric intestinal metaplasia: Long-term follow-up results

Baackground

Precancerous lesions are the most commonly cited factor in gastric cancer etiology. The sequence of events in intestinal-type gastric carcinogenesis is considered to be chronic gastritis, atrophy, intestinal metaplasia (IM), dysplasia, and carcinoma, respectively. Early diagnosis and treatment of advanced precursor lesions and gastric cancer is possible by identifying and monitoring patients with such premalignant lesions.

Aim

In our study, we aimed to evaluate the long-term follow-up results of intestinal metaplasia in our hospital and the rate of progression to malignancy by comparing these patients with patients who have undergone gastroscopy without a diagnosis of intestinal metaplasia.

Material and Method

One hundred and fifty-six followed-up patients out of 700 between the ages of 18 and 85 who were admitted to our hospital between 2009 and 2019, who were diagnosed with IM by pathological examination from biopsy material, and 150 patients who were not diagnosed with IM between 2009 and 2011 were included. The results of the cases were evaluated first retrospectively; then, the patients who were invited for control and underwent endoscopy were evaluated prospectively. IM and control groups were compared in terms of dysplasia and gastric cancer development. In addition, the IM group was compared in terms of 5 and 10 years of follow-up, extensive or local involvement, and complete and incomplete involvement in terms of dysplasia and cancer development.

Results

The follow-up period of the patients ranged from 1 to 10 years, and the mean follow-up interval was 4.2 ± 2.8 (min: 1; max: 10) years. Age, gender, and pathology results of the patients were examined in terms of IM type, localization of IM, pathology accompanying IM, and presence of Helicobacter pylori (Hp) infection and compared with the control group. While gastric carcinoma was detected in three of 156 patients in the IM group, gastric carcinoma was not detected in the follow-up of 150 patients in the control group. IM was most common in the antrum. Incomplete IM was detected in 89 patients, and complete IM in 69 patients. While two of the three patients with gastric carcinoma were localized to the antrum, one patient had incomplete-type IM and two patients had complete-type IM, and Hp was positive in two patients. While dysplasia was detected in nine of the patients diagnosed with IM, it was detected in two patients in the control group. A statistically significant difference was found between the IM and control groups in terms of dysplasia positivity (p = 0.037). On the other hand, no statistically significant difference was found between the IM and control groups in terms of age-group, gender, follow-up time group, and Hp positivity (p > 0.05). There was no significant difference between those who were followed up for 5 and 10 years in the IM group in terms of dysplasia and cancer development.

Conclusion

Therefore, it is considered that patients with intestinal metaplasia may be followed up at longer intervals, except for patients with race, ethnicity, incomplete type, extensive involvement, and a family history of gastric cancer.

Impact of Cancer Stem Cells on Therapy Resistance in Gastric Cancer

Gastric cancer (GC) is the fourth leading cause of cancer death worldwide, with an average 5-year survival rate of 32%, being of 6% for patients presenting distant metastasis. Despite the advances made in the treatment of GC, chemoresistance phenomena arise and promote recurrence, dissemination and dismal prognosis. In this context, gastric cancer stem cells (gCSCs), a small subset of cancer cells that exhibit unique characteristics, are decisive in therapy failure. gCSCs develop different protective mechanisms, such as the maintenance in a quiescent state as well as enhanced detoxification procedures and drug efflux activity, that make them insusceptible to current treatments. This, together with their self-renewal capacity and differentiation ability, represents major obstacles for the eradication of this disease. Different gCSC regulators have been described and used to isolate and characterize these cell populations. However, at the moment, no therapeutic strategy has achieved the effective targeting of gCSCs. This review will focus on the properties of cancer stem cells in the context of therapy resistance and will summarize current knowledge regarding the impact of the gCSC regulators that have been associated with GC chemoradioresistance.