Relation between bile acid reflux into the stomach and the risk of atrophic gastritis and intestinal metaplasia: a multicenter study of 2283 cases

A review of potential mechanisms and treatments of gastric intestinal metaplasia

Gastric intestinal metaplasia (GIM) is a pathological process where gastric mucosal epithelial cells are replaced by intestinal-type cells, serving as a precursor lesion for gastric cancer. This transformation involves various genetic and environmental factors, affecting key genes and signaling pathways. Recent research has revealed complex mechanisms, including changes in gene expression, abnormal signaling pathway activation, and altered cell behavior. This review summarizes the latest research on GIM, discussing its pathogenesis, current treatment strategies, and potential efficacy of emerging approaches like gene editing, microbiome interventions, and integrative medicine. By exploring these strategies, we aim to provide more effective treatments for GIM and reduce gastric cancer incidence. The review also highlights the importance of interdisciplinary studies in understanding GIM mechanisms and improving treatment strategies.

Crosstalk between bile acids and gut microbiota: a potential target for precancerous lesions of gastric cancer

As a critical juncture in the pathological continuum from gastritis to gastric cancer, precancerous lesions of gastric cancer (PLGC) are increasingly prevalent, significantly undermining the health of the global population. The primary constituents of bile, specifically bile acids (BAs), disrupt the equilibrium of gastric hormone secretion and compromise the structural integrity of the gastric mucosa, thereby facilitating gastric oncogenesis. Moreover, gut microbiota modulate host physiological and pathological processes through immune response regulation, metabolic pathway interference, and direct interaction with gastric tumor cells. Extensive research has elucidated that the metabolic dysregulation of BAs and gut microbiota, in concert with the resultant impairment of the gastric mucosa, are central to the pathogenesis of PLGC. In anticipation of future clinical preventive and therapeutic strategies, this review collates recent insights into the roles of BAs and gut bacteria in PLGC, examining their interplay and significance in the pathogenic mechanism of PLGC.

The Impact of Cholecystectomy on Bile Reflux After One Anastomosis Gastric Bypass

BACKGROUND

Bile reflux (BR) is an issue after one anastomosis gastric bypass (OAGB). Cholecystectomy can increase BR in patients without a history of metabolic and bariatric surgery. We aimed to evaluate the effect of cholecystectomy on BR after OAGB.

METHODS

This prospective observational study was conducted between March 2017 and December 2022 including 34 matched adult individuals with a body mass index ≥ 40 kg/m2 or ≥ 35 in the presence of comorbidities and gallstone disease in preop evaluations who underwent primary OAGB including 17 patients who had undergone cholecystectomy simultaneously or after OAGB (OAGB + LC) and 17 patients without cholecystectomy (OAGB). All patients underwent evaluations for gastroesophageal reflux disease (GERD) and bile reflux (BR) using various methods including esophagogastroduodenoscopy (EGD), the GERD-Q questionnaire, and a hepatobiliary iminodiacetic acid (HIDA) scan.

RESULTS

Thirty-four patients were included in this study. BR into the esophagus was not detected in both groups. BR to the gastric pouch was observed in 4 patients (23.5%) of the OAGB group and 6 patients (35.3%) of the OAGB + LC group (P = 0.452). BR to gastric remnant was observed in 6 patients (one and five patients in OAGB and OAGB + LC groups respectively) (P = 0.072). There was no statistically significant difference between the two groups, although it was clinically significant.

CONCLUSION

Cholecystectomy after OAGB is not associated with a change in the rate of BR in the gastric pouch but increases the incidence of BR into gastric remnant that may be harmful in the long term.

Deoxycholic acid inducing chronic atrophic gastritis with colonic mucosal lesion correlated to mucosal immune dysfunction in rats

The present study aimed to explore the underlying mechanism of bile reflux-inducing chronic atrophic gastritis (CAG) with colonic mucosal lesion. The rat model of CAG with colonic mucosal lesion was induced by free-drinking 20 mmol/L sodium deoxycholate to simulate bile reflux and 2% cold sodium salicylate for 12 weeks. In comparison to the control group, the model rats had increased abundances of Bacteroidetes and Firmicutes but had decreased abundances of Proteobacteria and Fusobacterium. Several gut bacteria with bile acids transformation ability were enriched in the model group, such as Blautia, Phascolarctobacter, and Enterococcus. The cytotoxic deoxycholic acid and lithocholic acid were significantly increased in the model group. Transcriptome analysis of colonic tissues presented that the down-regulated genes enriched in T cell receptor signaling pathway, antigen processing and presentation, Th17 cell differentiation, Th1 and Th2 cell differentiation, and intestinal immune network for IgA production in the model group. These results suggest that bile reflux-inducing CAG with colonic mucosal lesion accompanied by gut dysbacteriosis, mucosal immunocompromise, and increased gene expressions related to repair of intestinal mucosal injury.

Clinicopathological and endoscopic features of Helicobacter pylori infection-negative gastric cancer in Japan: a retrospective study

BACKGROUND/AIMS

Helicobacter pylori infection-negative gastric cancer (HPNGC) has not been systematically investigated in consecutive patients. Hence, this study aimed to investigate the clinicopathological and endoscopic features of HPNGC.

METHODS

This single-center retrospective study selected participants from patients with gastric cancer who were treated at the Fukuoka University Chikushi Hospital between January 2013 and December 2021. Only patients diagnosed with HPNGC were enrolled, and their clinicopathological and endoscopic features were analyzed in detail.

RESULTS

The prevalence of HPNGC in the present study was 2.6% (54/2112). The types of HPNGC observed in each gastric region were as follows: advanced gastric cancer was observed in the cardia; gastric adenocarcinoma of fundic-gland differentiation, gastric adenocarcinoma of foveolar-type presenting with whitish elevation and raspberry-like foveolar-type gastric adenocarcinoma, gastric adenocarcinoma arising in polyposis, and gastric adenocarcinoma with autoimmune gastritis were observed in the fundic gland region ranging from the gastric fornix to the gastric body; signet-ring cell carcinoma was observed in the gastric-pyloric transition region ranging from the lower gastric body to the gastric angle; and well-differentiated tubular adenocarcinoma with low-grade atypia was observed in the antrum.

CONCLUSIONS

This study revealed that tumors from each gastric region exhibited distinct macroscopic and histological types in HPNGC.

[Impact of primary duodenogastric reflux and Helicobacter pylori infection on gastritis and antibiotic resistance in children]

OBJECTIVES

To investigate the risk factors for Helicobacter pylori (HP) infection in children with primary duodenogastric reflux (DGR) and its impact on gastritis and antibioticresistance.

METHODS

A retrospective analysis was performed on the clinical data of 2 190 children who underwent upper gastrointestinal endoscopy in Wuxi Children's Hospital from January 2019 to February 2022, among whom 308 children were diagnosed with primary DGR. According to the presence or absence of HP infection, the children were classified to HP infection group (53 children) and non-HP infection group (255 children). The risk factors for HP infection and its impact on the incidence rate and severity of gastritis were analyzed. According to the presence or absence of primary DGR, 331 children with HP infection were classified to primary DGR group (29 children) and non-primary DGR group (302 children), and then the impact of primary DGR with HP infection on antibiotic resistance was analyzed.

RESULTS

The HP infection group had a significantly higher age than the non-HP infection group (P<0.05), and there was a significant difference in the age distribution between the two groups (P<0.05), while there were no significant differences in the incidence rate and severity of gastritis between the two groups (P>0.05). The multivariate logistic regression analysis showed that older age was a risk factor for HP infection in children with DGR (P<0.05). Drug sensitivity test showed that there were no significant differences in the single and combined resistance rates of metronidazole, clarithromycin, and levofloxacin between the primary DGR group and the non-primary DGR group (P>0.05).

CONCLUSIONS

Older age is closely associated with HP infection in children with DGR. Primary DGR with HP infection has no significant impact on gastritis and antibiotic resistance in children.

GATA4 Forms a Positive Feedback Loop with CDX2 to Transactivate MUC2 in Bile Acids-Induced Gastric Intestinal Metaplasia

Background/Aims

Gastric intestinal metaplasia (GIM), a common precancerous lesion of gastric cancer, can be caused by bile acid reflux. GATA binding protein 4 (GATA4) is an intestinal transcription factor involved in the progression of gastric cancer. However, the expression and regulation of GATA4 in GIM has not been clarified.

Methods

The expression of GATA4 in bile acid-induced cell models and human specimens was examined. The transcriptional regulation of GATA4 was investigated by chromatin immunoprecipitation and luciferase reporter gene analysis. An animal model of duodenogastric reflux was used to confirm the regulation of GATA4 and its target genes by bile acids.

Results

GATA4 expression was elevated in bile acid-induced GIM and human specimens. GATA4 bound to the promoter of mucin 2 (MUC2) and stimulate its transcription. GATA4 and MUC2 expression was positively correlated in GIM tissues. Nuclear transcription factor-κB activation was required for the upregulation of GATA4 and MUC2 in bile acid-induced GIM cell models. GATA4 and caudal-related homeobox 2 (CDX2) reciprocally transactivated each other to drive the transcription of MUC2. In chenodeoxycholic acid-treated mice, MUC2, CDX2, GATA4, p50, and p65 expression levels were increased in the gastric mucosa.

Conclusions

GATA4 is upregulated and can form a positive feedback loop with CDX2 to transactivate MUC2 in GIM. NF-κB signaling is involved in the upregulation of GATA4 by chenodeoxycholic acid.

Effect of bile reflux on gastric juice microbiota in patients with different histology phenotypes

BACKGROUND/AIMS

Bile reflux (BR) can influence the gastric environment by altering gastric acidity and possibly the gastric microbiota composition. This study investigated the correlation between bile acids and microbial compositions in the gastric juice of 50 subjects with differing gastric pathologies.

METHODS

This study included 50 subjects, which were categorized into three groups based on the endoscopic BR grading system. The primary and secondary bile acid concentrations in gastric juice samples were measured, and microbiota profiling was conducted using 16 S rRNA gene sequencing.

RESULTS

Significant differences were observed in each bile acid level in the three endoscopic BR groups (P < 0.05). The Shannon index demonstrated a significant decrease in the higher BR groups (P < 0.05). Analysis of the β-diversity revealed that BR significantly altered the gastric microbiota composition. The presence of neoplastic lesions and the presence of H. pylori infection impacted the β-diversity of the gastric juice microbiota. The abundance of the Streptococcus and Lancefielfdella genera exhibited positive correlations for almost all bile acid components(P < 0.05). In addition, the abundance of Slobacterium, Veillonella, and Schaalia showed positive correlations with primary unconjugated bile acids (P < 0.05).

CONCLUSION

Changes in microbial diversity in the gastric juice were associated with BR presence in the stomach. This result suggests that the degree of BR should be considered when studying the gastric juice microbiome.

Exploration of gastric carcinogenesis from the relationship between bile acids and intestinal metaplasia and intragastric microorganisms (H. pylori and non-H. pylori)

Gastric cancer (GC) is a prevalent form of cancer, with Helicobacter pylori (H. pylori) infection being the most common risk factor. Recent studies have highlighted the role of long-term irritation of the gastric mucosa caused by bile reflux in the development of cancer. Bile acids (BAs), which are a significant component in bile reflux, have the potential to promote gastric carcinogenesis through various mechanisms. These mechanisms include the induction of intestinal metaplasia (IM), inhibition of H. pylori activity, modification of H. pylori colonization, and alteration of the abundance and composition of microorganisms in the stomach. Defining the mechanism of bile acid-induced gastric carcinogenesis could potentially be an effective approach to prevent GC. Hence, this paper aims to review the mechanism of bile acid-induced IM, the association between BAs and H. pylori infection as well as microorganisms in the stomach, and the correlation between BAs and gastric carcinogenesis. The ultimate goal is to elucidate the role of BAs in the development of GC.

Does One-Anastomosis Gastric Bypass Expose Patients to Gastroesophageal Reflux: a Systematic Review and Meta-analysis

This systematic review and meta-analysis aimed to investigate the incidence of new-onset gastroesophageal reflux, reflux change, esophagitis, Barrett's esophagus, and revision due to reflux, gastritis, and marginal ulcer after one-anastomosis gastric bypass (OAGB). We performed subgroup analyses based on primary and revisional OAGB and time of follow-up. Meta-analysis of 87 studies with 27,775 patients showed a 6% rate of new-onset reflux after OAGB. Preoperative reflux status did not change significantly after OAGB. The rate of esophagitis and Barrett's esophagus was 15% and 1%, respectively. The new-onset reflux rate after OAGB was significantly higher than gastric bypass but not different with sleeve gastrectomy. The current study showed a relatively low rate of reflux and its complications after OAGB, but it was significantly higher than Roux-en-Y gastric bypass.

Inflammatory microenvironment in gastric premalignant lesions: implication and application

Gastric precancerous lesions (GPL) are a major health concern worldwide due to their potential to progress to gastric cancer (GC). Understanding the mechanism underlying the transformation from GPL to GC can provide a fresh insight for the early detection of GC. Although chronic inflammation is prevalent in the GPL, how the inflammatory microenvironment monitored the progression of GPL-to-GC are still elusive. Inflammation has been recognized as a key player in the progression of GPL. This review aims to provide an overview of the inflammatory microenvironment in GPL and its implications for disease progression and potential therapeutic applications. We discuss the involvement of inflammation in the progression of GPL, highlighting Helicobacter pylori (H. pylori) as a mediator for inflammatory microenvironment and a key driver to GC progression. We explore the role of immune cells in mediating the progression of GPL, and focus on the regulation of inflammatory molecules in this disease. Furthermore, we discuss the potential of targeting inflammatory pathways for GPL. There are currently no specific drugs for GPL treatment, but traditional Chinese Medicine (TCM) and natural antioxidants, known as antioxidant and anti-inflammatory properties, exhibit promising effects in suppressing or reversing the progression of GPL. Finally, the challenges and future perspectives in the field are proposed. Overall, this review highlights the central role of the inflammatory microenvironment in the progression of GPL, paving the way for innovative therapeutic approaches in the future.

Huangqi Jianzhong Tang treats chronic atrophic gastritis rats by regulating intestinal flora and conjugated bile acid metabolism

Huangqi Jianzhong Tang (HQJZ) is effective for treating chronic atrophic gastritis (CAG). The present study was carried out to reveal the mechanism of HQJZ in CAG rats. The metabolism and microbial composition of the cecal contents in CAG rats were analyzed through the integration of an untargeted metabolomic approach using ultra-high-performance liquid chromatography coupled with the quadrupole-time of flight mass spectrometry (UHPLC-QTOF-MS) and 16S rRNA gene sequencing, respectively. Finally, MetOrigin analyses were performed to explore the relationship between differential metabolites and intestinal flora. The results showed that HQJZ could significantly regulate metabolic disorders, especially conjugated acid metabolites. 16S rRNA gene sequencing analysis illustrated that HQJZ decreased the abundance of Acetobacter, Desulfovibrio, Escherichia, and Shigella. MetOrigin metabolite traceability analysis showed that the six bile acids associated with HQJZ efficacy included three bacteria-host cometabolites, which were involved in the primary bile acid biosynthesis pathway. Research presented here confirmed that conjugated bile acid metabolism was key to the treatment of CAG by HQJZ and correlates strongly with Bacteroides acidifaciens and Prevotella copri. These findings provide new insights into the mechanisms to explain the efficacy of HQJZ.

Assessment of the risk factors of duodenogastric reflux in relation to different dietary habits in a Chinese population of the Zhangjiakou area

Objective

To explore the risk factors of duodenogastric reflux (DGR) in relation to different dietary habits.

Methods

A total of 106 patients with symptoms of DGR who underwent electronic gastroscopy from June 2019 to June 2020 were selected and divided into the DGR group (n = 33) and the non-DGR group (n = 73) according to the diagnosis of bile reflux. Questionnaires were used to collect the basic information and dietary habits of the patients, including age, gender, body mass index, place of residence, comorbidities, dietary composition, salt intake, smoking and drinking consumption. The total bile acid (TBA) and cholesterol (CHO) of the gastric juice were measured using a fully automated biochemical analyser, with an enzyme-linked immunosorbent assay used for the serum cholecystokinin, gastrin and gastrin levels. Univariate analysis and multivariate logistic regression analysis were used to predict the attendant DGR risk factors.

Results

There was no significant difference in age or gender between the DGR and the non-DGR groups (P > 0.05). The proportion of patients living in the Bashang region was significantly higher in the DGR group (78.79%) than in the non-DGR group (38.36%) (P < 0.05). The levels of TBA and CHO in the gastric juice and the cholecystokinin and gastrin levels in the serum of the DGR group were higher than those in the non-DGR group, while the serum motilin levels were significantly lower in the DGR group than in the non-DGR group (P < 0.05). The univariate analysis indicated that the proportion of patients with daily consumption of dairy products and fried foods, a high salt intake and smoking and drinking consumption were significantly higher in the DGR than in the non-DGR group (P < 0.05).

Conclusion

The daily consumption of dairy products and a preference for fried food are independent risk factors for the occurrence of DGR (odds ratio ≥ 1, P < 0.05).

Association between history of cholecystectomy and risk of gastric cancer: a meta-analysis of epidemiological studies

PURPOSE

Evidence from previous studies on the association between cholecystectomy and risk of gastric cancer are still inconsistent. We aimed at conducting a meta-analysis of epidemiological studies to evaluate this association.

METHODS

Researchers searched three databases (PubMed, Embase and Web of Science) through January 2021 for eligible studies. Relative risks (RRs) and 95% CIs in each included studies were pooled by random-effects models. Patients and the public were not involved in our study.

RESULTS

Eight studies were identified. Four studies reported significantly positive association between history of cholecystectomy and risk of gastric cancer, and the remaining studies reported null association. The pooled RR of these eight studies showed that a history of cholecystectomy was associated with a 11% higher risk of gastric cancer (pooled RR=1.11, 95% CI: 1.03 to 1.20). Moderate heterogeneity across the studies was detected (p=0.117, I2=37.8%). The pooled RRs were 1.12 (95% CI: 1.01 to 1.24) for five cohort studies and 0.95 (95% CI: 0.66 to 1.38) for three case-control studies. Compared with the risk in Europe and the USA, the pooled RR was higher for two studies conducted in Asia. Six studies were assessed as high-quality studies with the pooled RR of 1.12 (95% CI: 1.02 to 1.23). The pooled results were robust by sensitivity analyses, and no indication of publication bias was detected.

CONCLUSION

This meta-analysis suggests that a history of cholecystectomy may be associated with an increased risk of gastric cancer.

Potential tactics with certain gut microbiota for the treatment of unresectable hepatocellular carcinoma

Hepatocellular carcinoma (HCC) constitutes an extremely malignant form of primary liver cancer. Intricate connections linking to the immune system might be associated with the pathogenesis of HCC. Meanwhile, immunotherapy with immune checkpoint inhibitors has been established to be a favorable therapeutic possibility for advanced HCC. Although curative opportunities for advanced HCC are restricted, the immune checkpoint immunotherapy has developed as the main choice for treating HCC. However, patients with metabolic-associated fatty liver disease (MAFLD)-linked HCC might be less likely to benefit from the immunotherapy alone. The limitation of the effect of the immunotherapy might be owing to the impaired T cell activation in MAFLD patients, which could be well explained by a dysfunctional gut-liver axis. Gut microbiota and their metabolites including several bile acids could contribute to modulating the responses of the immune checkpoint immunotherapy. Roles of gut microbiota in the development of cancers have expected great interest in the latest studies. Here, an interplay between the gut and liver has been presented, which might suggest to affect the efficacy of immune checkpoint immunotherapy against HCC.

Randomised clinical trial: 3-year interim analysis results of the VISION trial to evaluate the long-term safety of vonoprazan as maintenance treatment in patients with erosive oesophagitis

BACKGROUND

VISION is a randomised, phase 4, open-label, parallel-group, multicentre study conducted in 33 centres in Japan. The aim of this study was to assess the long-term safety of vonoprazan for maintenance treatment of healed erosive oesophagitis versus lansoprazole.

METHODS

Patients with endoscopically diagnosed erosive oesophagitis were randomised 2:1 to once-daily vonoprazan 20 mg or lansoprazole 30 mg, for a 4- to 8-week healing phase. Patients with endoscopically confirmed healing entered a 260-week maintenance phase with a once-daily starting dose of vonoprazan 10 mg or lansoprazole 15 mg. Primary endpoint was change in gastric mucosal histopathology.

RESULTS

Of 208 patients (vonoprazan, n = 139; lansoprazole, n = 69) entering the healing phase, 202 entered the maintenance phase (vonoprazan, n = 135; lansoprazole, n = 67). At 3 years, 109 vonoprazan-treated and 58 lansoprazole-treated patients remained on treatment. Histopathological evaluation of gastric mucosa showed that hyperplasia of parietal, foveolar and G cells was more common with vonoprazan than lansoprazole at week 156 of the maintenance phase. There was no marked increase in the occurrence of parietal, foveolar and G cell hyperplasia among patients in the vonoprazan group from week 48 to week 156. Histopathological evaluation of the gastric mucosa also showed no neoplastic changes in either group. No new safety issues were identified.

CONCLUSIONS

In this interim analysis of VISION, no new safety concerns were identified in Japanese patients with healed erosive oesophagitis receiving vonoprazan or lansoprazole as maintenance treatment for 3 years. (CT.gov identifier: NCT02679508; JapicCTI-163153; Japan Registry of Clinical Trials: jRCTs031180040).

Endoscopic Transoral Outlet Reduction for the Treatment of Biliary Reflux Symptoms in Patients After One-Anastomosis Gastric Bypass-a Case Series

PURPOSE

OAGB is the third most common bariatric surgery. Biliary reflux (BR) is an inherent complication of this unique anatomy, although there is still controversy regarding its significance and long-term risks including carcinogenesis. To date, there is no effective treatment for BR with conversion to RYGB reserved for refractory patients. TORe is an effective treatment for weight-regain and dumping syndrome after RYGB. We hypothesized that narrowing the anastomosis would decrease the amount of bile refluxate entering the stomach and esophagus in patients with BR symptoms after OAGB and alleviate symptoms. The purpose of this study is to evaluate the efficacy of TORe for the treatment of BR symptoms after OAGB.

MATERIALS AND METHODS

BR was diagnosed clinically in patients after OAGB using the gastroesophageal reflux disease health-related quality of life (GERD-HRQL) instrument after treatment with high-dose proton pump inhibitor (PPI) excluded possible acid reflux. TORe was carried out using a suture pattern that narrowed and elongated the anastomosis. All patients were prospectively followed.

RESULTS

Twelve patients, post-OAGB, underwent TORe for BR. Symptoms resolved in 9 (75%) patients. GERD-HRQL score at 6 months declined from an average of 33.7 (SD 1.9) before the procedure to 16.1 (SD 10, p < 0.001). In one case, a small perforation was identified during the procedure and was immediately sutured with no further sequela.

DISCUSSION

TORe appears a safe and effective treatment for BR symptoms after OAGB, at least in the short term. Accurate tools for BR diagnosis, a larger cohort, and longer follow-up periods are needed to better show the effectiveness and durability of this treatment option.

Diagnostic Principles for Chronic Gastritis Associated with Duodenogastric Reflux

This article systematizes available data from the literature on biliary gastritis (BG) in order to increase the awareness of specialists about the latest possibilities for diagnosing the disease. BG occurs as a result of pathological duodenogastric reflux. In patients with a preserved duodenogastric junction, the dominant factor is represented by motor disorders of the upper digestive tract (primary biliary gastritis), while in patients recovering from surgical interventions it is represented by structural changes (secondary biliary gastritis). Progressive BG can lead to atrophy of the gastric mucosa, intestinal metaplasia, epithelial dysplasia, and eventually to gastric cancer. Diagnostic methods for BG are carried out to identify risk factors, exclude alarm symptoms and identify persistent motor disorders and pathological reflux (24 h pH-impedancemetry, hepatobiliary scintigraphy, 24 h monitoring of bilirubin content in the reflux using a Bilitec 2000 photometer), as well as to diagnose gastritis itself (esophagogastroduodenoscopy, morphological gastrobiopsy examination). The diagnosis of BG should be based on a multidisciplinary approach that combines a thorough analysis of a patient's complaints, an anamnesis of the disease, and the results of endoscopic and histological research methods.

Diagnostic Principles for Chronic Gastritis Associated with Duodenogastric Reflux

This article systematizes available data from the literature on biliary gastritis (BG) in order to increase the awareness of specialists about the latest possibilities for diagnosing the disease. BG occurs as a result of pathological duodenogastric reflux. In patients with a preserved duodenogastric junction, the dominant factor is represented by motor disorders of the upper digestive tract (primary biliary gastritis), while in patients recovering from surgical interventions it is represented by structural changes (secondary biliary gastritis). Progressive BG can lead to atrophy of the gastric mucosa, intestinal metaplasia, epithelial dysplasia, and eventually to gastric cancer. Diagnostic methods for BG are carried out to identify risk factors, exclude alarm symptoms and identify persistent motor disorders and pathological reflux (24 h pH-impedancemetry, hepatobiliary scintigraphy, 24 h monitoring of bilirubin content in the reflux using a Bilitec 2000 photometer), as well as to diagnose gastritis itself (esophagogastroduodenoscopy, morphological gastrobiopsy examination). The diagnosis of BG should be based on a multidisciplinary approach that combines a thorough analysis of a patient’s complaints, an anamnesis of the disease, and the results of endoscopic and histological research methods.

Alteration of gastric microbiota and transcriptome in a rat with gastric intestinal metaplasia induced by deoxycholic acid

Objective

Bile reflux plays a key role in the development of gastric intestinal metaplasia (GIM), an independent risk factor of gastric cancer. Here, we aimed to explore the biological mechanism of GIM induced by bile reflux in a rat model.

Methods

Rats were treated with 2% sodium salicylate and allowed to freely drink 20 mmol/L sodium deoxycholate for 12 weeks, and GIM was confirmed by histopathological analysis. Gastric microbiota was profiled according to the 16S rDNA V3-V4 region, gastric transcriptome was sequenced, and serum bile acids (BAs) were analyzed by targeted metabolomics. Spearman's correlation analysis was used in constructing the network among gastric microbiota, serum BAs, and gene profiles. Real-time polymerase chain reaction (RT-PCR) measured the expression levels of nine genes in the gastric transcriptome.

Results

In the stomach, deoxycholic acid (DCA) decreased the microbial diversity but promoted the abundances of several bacterial genera, such as Limosilactobacillus, Burkholderia-Caballeronia-Paraburkholderia, and Rikenellaceae RC9 gut group. Gastric transcriptome showed that the genes enriched in gastric acid secretion were significantly downregulated, whereas the genes enriched in fat digestion and absorption were obviously upregulated in GIM rats. The GIM rats had four promoted serum BAs, namely cholic acid (CA), DCA, taurocholic acid, and taurodeoxycholic acid. Further correlation analysis showed that the Rikenellaceae RC9 gut group was significantly positively correlated with DCA and RGD1311575 (capping protein-inhibiting regulator of actin dynamics), and RGD1311575 was positively correlated with Fabp1 (fatty acid-binding protein, liver), a key gene involved in fat digestion and absorption. Finally, the upregulated expression of Dgat1 (diacylglycerol acyltransferase 1) and Fabp1 related to fat digestion and absorption was identified by RT-PCR and IHC.

Conclusion

DCA-induced GIM enhanced gastric fat digestion and absorption function and impaired gastric acid secretion function. The DCA-Rikenellaceae RC9 gut group-RGD1311575/Fabp1 axis might play a key role in the mechanism of bile reflux-related GIM.

The role of bile acid in intestinal metaplasia

A precancerous lesion of gastric cancer (GC), intestinal metaplasia (IM) is a pathological transformation of non-intestinal epithelium into an intestinal-like mucosa. It greatly raises the risk of developing the intestinal type of GC, which is frequently observed in the stomach and esophagus. It is understood that esophageal adenocarcinoma's precursor lesion, chronic gastroesophageal reflux disease (GERD), is what causes Barrett's esophagus (BE), an acquired condition. Recently, Bile acids (BAs), which are one of the compositions of gastric and duodenal contents, have been confirmed that it led to the occurrence and development of BE and gastric intestinal metaplasia (GIM). The objective of the current review is to discuss the mechanism of IM induced by bile acids. This review serves as a foundation for further research aimed at improving the way BE and GIM are currently managed.

Chinese integrated guideline on the management of gastric precancerous conditions and lesions

The standardized diagnosis and management of gastric precancerous conditions and lesions are important to prevent gastric cancer. This guideline, created by 5 traditional Chinese medicine and Western medicine associations, based on the current morbidity and diagnosis and treatment of gastric precancerous conditions and lesions, provides specific key points and strategies for diagnosis and treatment in the following five aspects: definition and epidemiology, diagnosis and stage, surveillance, treatment and efficacy evaluation. It is hoped that these aspects, assessed by integrating Western medicine and traditional Chinese medicine and involving multidisciplinary participation, will play a guiding role in clinical diagnosis and treatment and achieve effective secondary prevention of gastric cancer.

Negative correlations between bile reflux gastritis and Helicobacter pylori infection

OBJECTIVE

There are a few articles to study the relationship between bile reflux gastritis (BRG) and H. pylori infection, and the results are debatable. This study set out to determine the relationship between BRG and Helicobacter pylori (H. pylori) infection.

METHODS

In this retrospective study, patients from January, 1st 2013 to January, 1st, 2021 were divided into two groups based on whether they had BRG. The control group was got by 1:1 propensity-score matching (PSM) based on age and sex. Then, the relationship between BRG and H. pylori in patients was analyzed via Chi-squared test and Phi (φ) detection.

RESULTS

26449 patients were included in this study, and there were 1918 patients in each group after age and sex matching. patients with HP were responsible for 35% (9345/26449) and patients with BRG were 7% (1918/26449). Further relationship exploration, there is a negative, but weak, the relationship between BRG and HP infection (X² = 45.62, p < .001, Phi (φ)= -0.109).

CONCLUSION

Patients with bile reflux may have less likely to get HP infection. HP eradication is an important thing for the prevention of gastric cancer and this study serves as a foundation and may provide directions for future research.

A Case of Helicobacter pylori-negative Gastric Adenocarcinoma Mimicking Verrucous Gastritis in the Antrum: A Case Report and Literature Review

A 46-year-old man was referred to our hospital for the examination of a flat elevated lesion with an erosion-like depression, located on the greater curvature of the antrum. Endoscopic submucosal dissection was performed. Histological findings of the resected specimen demonstrated a well-differentiated tubular adenocarcinoma with a diameter of 12 mm. No atrophy was observed in the tumor-adjacent mucosa. Serum Helicobacter pylori antibody estimation and ¹³C-urea breath tests yielded negative results. Immunohistochemical staining was positive for both gastric mucin and intestinal mucin. The final diagnosis was well-differentiated tubular adenocarcinoma with a gastrointestinal phenotype that originated in mucosa uninfected by H. pylori.

Bile reflux and bile acids in the progression of gastric intestinal metaplasia

ABSTRACT

Gastric intestinal metaplasia (GIM) is a precancerous lesion of gastric cancer (GC) and is considered an irreversible point of progression for GC. Helicobacter pylori infection can cause GIM, but its eradication still does not reverse the process. Bile reflux is also a pathogenic factor in GIM and can continuously irritate the gastric mucosa, and bile acids in refluxed fluid have been widely reported to be associated with GIM. This paper reviews in detail the relationship between bile reflux and GIM and the mechanisms by which bile acids induce GIM.

Iron deficiency linked to altered bile acid metabolism promotes Helicobacter pylori-induced inflammation-driven gastric carcinogenesis

Gastric carcinogenesis is mediated by complex interactions among Helicobacter pylori, host, and environmental factors. Here, we demonstrate that H. pylori augmented gastric injury in INS-GAS mice under iron-deficient conditions. Mechanistically, these phenotypes were not driven by alterations in the gastric microbiota; however, discovery-based and targeted metabolomics revealed that bile acids were significantly altered in H. pylori-infected mice with iron deficiency, with significant upregulation of deoxycholic acid (DCA), a carcinogenic bile acid. The severity of gastric injury was further augmented when H. pylori-infected mice were treated with DCA, and, in vitro, DCA increased translocation of the H. pylori oncoprotein CagA into host cells. Conversely, bile acid sequestration attenuated H. pylori-induced injury under conditions of iron deficiency. To translate these findings to human populations, we evaluated the association between bile acid sequestrant use and gastric cancer risk in a large human cohort. Among 416,885 individuals, a significant dose-dependent reduction in risk was associated with cumulative bile acid sequestrant use. Further, expression of the bile acid receptor transmembrane G protein-coupled bile acid receptor 5 (TGR5) paralleled the severity of carcinogenic lesions in humans. These data demonstrate that increased H. pylori-induced injury within the context of iron deficiency is tightly linked to altered bile acid metabolism, which may promote gastric carcinogenesis.

Gastrointestinal neoplasia: carcinogenic interaction between bile acids and Helicobacter pylori in the stomach

Bile acids modulate cell functions in health and disease, however, the mechanisms underlying their actions on neoplastic cells in the gastrointestinal (GI) tract remain largely unknown. In this issue of the JCI, Noto et al. comprehensively analyzed how interactions between Helicobacter pylori infection, iron deficiency, and bile acids modulate gastric inflammation and carcinogenesis. The investigators used sophisticated models, including INS-GAS mice with elevated serum gastrin and gastric acid secretion, in which H. pylori infection mimics human disease progression, to show that selected bile acids potentiated the carcinogenic effects of H. pylori infection and iron depletion. This elegant work has broad translational implications for microbe-associated GI neoplasia. Importantly, bile acid sequestration robustly attenuated the combined effects of H. pylori infection and iron depletion on gastric inflammation and cancer.

Bile Acid-Microbiome Interaction Promotes Gastric Carcinogenesis

Bile reflux gastritis (BRG) is associated with the development of gastric cancer (GC), but the specific mechanism remains elusive. Here, a comprehensive study is conducted to explore the roles of refluxed bile acids (BAs) and microbiome in gastric carcinogenesis. The results show that conjugated BAs, interleukin 6 (IL-6), lipopolysaccharide (LPS), and the relative abundance of LPS-producing bacteria are increased significantly in the gastric juice of both BRG and GC patients. A secondary BA, taurodeoxycholic acid (TDCA), is significantly and positively correlated with the LPS-producing bacteria in the gastric juice of these patients. TDCA promotes the proliferation of normal gastric epithelial cells (GES-1) through activation of the IL-6/JAK1/STAT3 pathway. These results are further verified in two mouse models, one by gavage of TDCA, LPS, and LPS-producing bacteria (Prevotella melaninogenica), respectively, and the other by bile reflux (BR) surgery, mimicking clinical bile refluxing. Moreover, the bile reflux induced gastric precancerous lesions observed in the post BR surgery mice can be prevented by treatment with cryptotanshinone, a plant-derived STAT3 inhibitor. These results reveal an important underlying mechanism by which bile reflux promotes gastric carcinogenesis and provide an alternative strategy for the prevention of GC associated with BRG.

Microbial Characteristics of Common Tongue Coatings in Patients with Precancerous Lesions of the Upper Gastrointestinal Tract

The tongue coating (TC) microbiota, a crucial component of the tongue coating, illustrates a huge microbial percentage of the body that mostly includes actinobacteria, bacteroides, firmicutes, and fusobacteria. The TC microbiota is closely related to the development of upper gastrointestinal malignancies, such as oral, gastric, and esophageal cancer. Nonetheless, the microbiological characteristics of common TCs in individuals with precancerous lesions of the upper gastrointestinal tract are still unclear. Herein, we designed a case-control study, recruiting 153 PLUGT patients with four different types of TCs, including 47 white-thin, 19 white-thick, 47 yellow-thin, and 40 yellow-thick, as well as 47 volunteers as controls. To analyze microbial characteristics, 16S rRNA microbiome approaches were used. An enzyme-linked immunosorbent assay (ELISA) was employed to assess serum IL-17A and total bile acid (TBA). According to the obtained results, Leptotrichia was found to be a promising biomarker for thin as well as thick yellow coatings. In comparison to the control TC microbiota, 39 different genera developed commensal networks in common TCs. Lachnoanaerobaculum and pseudonocardia were the most striking core bacteria. Lachnoanaerobaculum positively correlated with Leptotrichia in W-thin and Y-thick coatings, with actinomyces and methylobacterium in Y-thin coatings, with Campylobacter in Y-thick coatings, and with Bradyrhizobium in W-thick and Y-thick coatings. Serum IL-17A levels were greater in cases with W-thin coating than in controls, and serum IL-17A was positively linked with Parvimonas in patients with W-thick or Y-thin coating. In Y-thin coating, the oral dominating bacteria Streptococcus was negatively linked with serum TBA. Taken together, the promoted bacteria were found to be synergistically proliferative in the TCs of PLUGT patients. The diverse TCs had distinct bacterial commensal networks, whereas the common TCs were linked by specific bacteria to serum IL-17A and TBA.

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.

Roles and action mechanisms of bile acid-induced gastric intestinal metaplasia: a review

Gastric intestinal metaplasia (IM) is a precancerous lesion that increases the risk of subsequent gastric cancer (GC) development. Therefore, the mechanism of IM has been the focus of basic and clinical research. Helicobacter pylori (H. pylori) infection has been recognized as the main pathogenesis of gastric IM. However, more and more studies have shown that chronic inflammation of gastric mucosa caused by bile reflux is the key pathogenic factor of gastric IM. Bile reflux activates the expression of IM biomarkers via the bile acid receptor. In addition, microRNAs, exosomes, and epigenetics are also involved in the occurrence and development of bile acid-induced gastric IM. Currently, the relevant research is still very few. The molecular mechanism of the phenotypic transformation of gastrointestinal epithelial cells induced by bile acids has not been fully understood. This article mainly reviews the physiology and pathology of bile acid, mechanism of gastric IM induced by bile acid, bile acid receptors, and so on, in order to provide reference for further research.

Primary bile acid activates Egr‑1 expression through the MAPK signaling pathway in gastric cancer

Bile acids have been linked to pathomechanism and prognosis in various types of cancers. The present study aimed to investigate the effect of bile acids on the molecular change in gastric epithelial cancer cells and to evaluate gastric bile acid concentration in patients with early gastric cancer (EGC). Human gastric cancer cells (AGS and NCI‑N87 cell lines) were treated with several bile acid types to determine their effect on molecular changes in the cells. Gastric levels of individual bile acids were measured (primary unconjugated or conjugated bile acids and secondary bile acids) in 39 participants (20 controls and 19 patients with EGC). Exposing gastric epithelial cancer cells to primary bile acids in vitro upregulated the expression of early growth response factor 1 (Egr‑1) and the oncogenes including c‑Jun, c‑Myc and Snail, whereas a p42/44 MAPK inhibitor exposure reduced their expression. There was a significant difference in age and presence of atrophic gastritis with intestinal metaplasia in background mucosa between controls and patients with EGC. There were significant differences in the levels of unconjugated or conjugated primary bile acids between controls and EGC patients except lithocholic acid. After adjustment of age and presence of atrophic gastritis with intestinal metaplasia, the levels of cholic acid [adjusted odds ratio (aOR) 4.3; 95% confidence interval (CI): 1.2‑16.2; P=0.029] and glycochenodeoxycholic acid [aOR 9.9; 95% CI: 1.3‑75.3; P=0.027] were significantly higher in patients with EGC compared with controls. In conclusion, bile acids upregulate Egr‑1 in gastric cancer cells via the MAPK signaling pathway, and higher gastric levels of primary bile acids are associated with EGC. Therefore, exposure of gastric cells to primary bile acids may play a role in gastric carcinogenesis.

Intestinal-type gastric dysplasia in Helicobacter pylori-naïve patients

Gastric dysplasia and gastric cancer in Helicobacter pylori (Hp)-naïve patients usually exhibit a gastric phenotype, reflecting gastric mucosa without intestinal metaplasia (IM). We showed that intestinal-type gastric dysplasia (IGD) rarely occurs in the Hp-naïve stomach. In the last 10 years, we treated 1760 gastric dysplasia and gastric cancer patients, with 3.6% (63/1760) being Hp-naïve. Among these, ten were diagnosed with 14 IGDs and enrolled in this retrospective analysis. All lesions were observed by white-light endoscopy (WLE) and narrow-band imaging with magnification endoscopy (NBIME). We analyzed their endoscopic and microscopic features and patient demographics. Five men and five women aged 64 ± 21 years were included. WLE showed the depressed lesions mimicking a benign raised erosion in the prepyloric compartment. Multiple growths were confirmed in 30% (3/10) of patients. NBIME showed a near-regular microstructure and capillaries in 50% (7/14) of lesions with a gastritis-like appearance. Histologically, background mucosa was non-atrophic pyloric gland tissue, but 40.0% of samples (4/10) contained sporadic IM. Most of the lesions (8/14) were low-grade dysplasia, and others had a high-grade component, with one progressing to intramucosal carcinoma. The neoplastic surface was widely covered with foveolar epithelium in 57.1% (8/14). Immunohistochemically, neoplastic cells expressed CDX2 in all patients (14/14), MUC2 and CD10 in 92.9% (13/14), MUC5AC in 14% (2/14), and no expression of MUC6, showing an intestinal phenotype. Ki-67 was overexpressed with a mean labeling index of 58.3 ± 38.5%, and p-53 was overexpressed in 92.9% (13/14), regardless of the dysplastic grade. The IGD rarely occurs in Hp-naïve patients with distinctive clinicopathologic characteristics.

The Spatial Landscape of the Bacterial Community and Bile Acids in the Digestive Tract of Patients With Bile Reflux

Background

Bile reflux can lead to inflammation and increased intestinal metaplasia. Since bile acids can influence the gastrointestinal environment, it is possible that bile reflux may alter the gastric microbiota and potentially the oral or gut microbiota. Bile acids have a very complex interrelationship with microbiota. We aimed to explore the characteristics of the digestive tract microbiota and bile acids profile in bile reflux patients.

Methods

This study included 20 chronic gastritis patients with bile reflux and 20 chronic gastritis patients without bile reflux. Saliva, gastric fluid, and fecal samples were collected for bile acid testing. Buccal mucosal swabs, gastric mucosal tissues, and feces were collected for bacteria detection. The UPLC-MS/MS examined bile acids profiles. 16S rRNA gene sequencing was used to analyze the bacterial profile.

Results

Bilirubin in the blood increased in bile reflux patients. No other clinical factors were identified to be significantly associated with bile reflux. 12-DHCA, 6,7-diketo LCA, and βHDCA decreased while TUDCA increased in saliva of bile reflux patients. Streptococcus, Capnocytophaga, Neisseria, and Actinobacillus decreased in oral mucosa of bile reflux patients while Helicobacter, Prevotella, and Veillonella increased. Gastric bile acid levels were generally higher in bile reflux patients. Gastric mucosal microbiota was highly stable. The changes in fecal bile acids were insignificant. Bifidobacterium, Prevotella_2, Ruminococcus, Weissella, Neisseria, and Akkermansia decreased in fecal samples from bile reflux patients; while Alloprevotella, Prevotella_9, Parabacteroides, and Megamonas increased.

Conclusion

Our results demonstrate that bile reflux significantly alters the oral, gastric, and intestinal bile acids profiles but only influences the oral and gut microbiota composition. These findings indicate that bile reflux can modulate the gastrointestinal microbiota in a site-specific manner.

Pyloric Incompetence Associated with Helicobactor pylori Infection and Correlated to the Severity of Atrophic Gastritis

Duodenogastric reflux (DGR) causes bile reflux gastritis (BRG) and may develop into gastric cancer. DGR is classified as primary in non-operated stomachs or secondary to surgical intervention. Primary DGR and Helicobacter pylori (H. pylori) infection are reportedly related. However, the mechanism is not fully understood. This study aimed to elucidate the relationship between H. pylori infection and pyloric incompetence in a non-operated stomach. A total of 502 non-operated participants who underwent an upper intestinal endoscopy were prospectively enrolled. Endoscopic findings (EAC, endoscopic atrophy classification; nodular gastritis; xanthoma; fundic gland polyp; and incompetence of pylorus), sex, age, gastrin, pepsinogen (PG) I and PG II levels were evaluated. PG I/PG II ratio, anti-H. pylori-Ab positivity, and atrophic gastritis status were significantly different between the normal and incompetent pylori (p = 0.043, <0.001, and 0.001, respectively). Open-type atrophic gastritis was significantly higher in the incompetent pylori. Incompetence of the pylorus and EAC were moderately correlated (Cramer’s V = 0.25). Multivariate analysis revealed that the presence of anti-H. pylori-Ab was the only independent factor associated with the incompetence of the pylorus, with an adjusted odds ratio of 2.70 (95% CI: 1.47−4.94, p = 0.001). In conclusion, pyloric incompetence was associated with H. pylori infection and moderately correlated to the severity of atrophic gastritis in non-operated stomachs.

Deoxycholic acid induces gastric intestinal metaplasia by activating STAT3 signaling and disturbing gastric bile acids metabolism and microbiota

Intestinal metaplasia (IM) is the inevitable precancerous stage to develop intestinal-type gastric cancer (GC). Deoxycholic acid (DCA) is the main bile acid (BA) component of duodenogastric reflux and has shown an increased concentration during the transition from chronic gastritis to IM associated with continued STAT3 activation. However, the mechanisms underlying how DCA facilitates IM in the gastric epithelium need exploration. We evaluated IM and bile reflux in corpus tissues from 161 subjects undergoing GC screening. Cell survival and proliferation, proinflammatory cytokine expression and TGR5/STAT3/KLF5 axis activity were measured in normal human gastric cells, cancer cells, and organoid lines derived from C57BL/6, FVB/N and insulin-gastrin (INS-GAS) mice treated with DCA. The effects of DCA on IM development were determined in INS-GAS mice with long-term DCA supplementation, after which the gastric bacterial and BA metabolic profiles were measured by 16S rRNA gene sequencing and LC-MS. We revealed a BA-triggered TGR5/STAT3/KLF5 pathway in human gastric IM tissues. In gastric epithelial cells, DCA promoted proliferation and apoptotic resistance, upregulated proinflammatory cytokines and IM markers, and facilitated STAT3 phosphorylation, nuclear accumulation and DNA binding to the KLF5 promoter. DCA triggered STAT3 signaling and the downstream IM marker KLF5 in mouse gastric organoids in vitro and in vivo. In INS-GAS mice, DCA promoted the accumulation of serum total BAs and accelerated the stepwise development of gastric IM and dysplasia. DCA induced gastric environmental alterations involving abnormal BA metabolism and microbial dysbiosis, in which the Gemmobacter and Lactobacillus genera were specifically enriched. Lactobacillus genus enrichment was positively correlated with increased levels of GCA, CA, T-α-MCA, TCA and β-MCA in DCA-administrated INS-GAS mice. DCA promotes nuclear STAT3 phosphorylation, which mediates KLF5 upregulation associated with gastric inflammation and IM development. DCA disturbs the gastric microbiome and BA metabolism homeostasis during IM induction.

Analysis of Risk Factors and Establishment of a Prediction Model for Endoscopic Primary Bile Reflux: A Single-Center Retrospective Study

Background: Endoscopic primary bile reflux is one of the main diagnostic criteria for bile reflux gastritis (BRG). Presently, the risk factors and prediction models of endoscopic primary bile reflux (EPBR) in gastropathy patients who cannot or will not undergo endoscopy due to contraindications are not clear. Thus, this study aimed to evaluate the risk factors of EPBR and to establish and verify a prediction model.

Methods: A series of 844 patients (564 subjects with EPBR and 280 control subjects) were retrospectively selected for this study and divided into a training set (n = 591) and a validation set (n = 253) according to the usual ratio of 70:30% for the subsequent internal validation of the logistic regression model for EPBR. Fifteen parameters that might affect the occurrence of EPBR were collected. Subsequently, univariate and stepwise logistic regression analyses were introduced to reveal the risk factors and the multivariate prediction model. An R package was dedicated to the corresponding internal validation of the EPBR model.

Results: The univariate analysis showed that gender, age, smoking, Helicobacter pylori (H. pylori) infection status, metabolic syndrome (MS), non-steroidal anti-inflammatory drugs (NSAIDs) use history, and previous medical histories of chronic liver diseases, cholelithiasis, and erosive gastritis were statistically significant between the two groups (P < 0.05). Multivariate regression described that being a male [OR (95%confidence interval (CI)) = 2.29 (1.50–3.50), P < 0.001], age≥45 years old [OR (95% CI) = 4.24 (2.59–6.96), P < 0.001], H. pylori infection status [OR (95% CI) = 2.34 (1.37–4.01), P = 0.002], MS [OR (95% CI) = 3.14 (1.77–5.54), P < 0.001], NSAIDs use history [OR (95% CI) = 1.87 (1.03–3.40), P = 0.04], cholelithiasis history [OR (95% CI) = 3.95 (2.18–7.18), P < 0.001] and erosive gastritis history [OR (95% CI) = 6.77 (3.73–12.29), P < 0.001] were the risk factors for the occurrence of EPBR. Based on the results of these risk factors, an EPBR prediction model with an adequate calibration and excellent discrimination was established [area under the curve (AUC): 0.839, 95% CI = 0.806–0.872].

Conclusions: Being a male, age ≥ 45 years old, H. pylori infection, histories of MS, NSAIDs use, cholelithiasis, and erosive gastritis appear to be the risk factors for EPBR, and our favorable prediction model might be an option for the prediction of EPBR.

Gastric neoplasms in patients with familial adenomatous polyposis: endoscopic and clinicopathologic features

BACKGROUND AND AIMS

Gastric neoplasms in patients with familial adenomatous polyposis (FAP) occur at a high rate and can cause death. The endoscopic findings of gastric neoplasms in these patients are characteristic but not well recognized. To identify the relevant characteristics to enable early detection, we retrospectively investigated endoscopic findings of gastric neoplasms in patients with FAP and then compared the clinical, histopathologic, and genetic features among subgroups.

METHODS

Of 234 patients with 171 pedigrees at 2 institutes, 56 cases (24%, 133 gastric neoplasms) with 44 pedigrees were examined. Immunostaining was performed for histopathologic evaluation by 1 blinded pathologist. According to the endoscopic findings, gastric neoplasms were divided into 4 types based on location (L: antrum and pylorus, UM: the rest of the stomach) and color (W: white, T: translucent, R: reddish) and their clinicopathologic features examined.

RESULTS

Of the cases, 93% could be classified into a single type. Among histologic phenotypes, high-grade dysplasia was present in 26% (type L), 41% (type UM-W), 0% (type UM-T), and 22% (type UM-R). The immunologic phenotype comprised the gastric type in 69% (93% in Type UM) and the intestinal phenotype, including the mixed type, in 31% (61% in type L). Moreover, 96% of patients had concurrent duodenal neoplasms. Adenomatous polyposis coli gene status was identified in 93% of patients; the pathogenic variant was detected in 98% but did not influence any endoscopic features.

CONCLUSIONS

Gastric neoplasms in patients with FAP were stratified into 4 types according to their endoscopic findings. The endoscopic phenotype was related to the histopathologic phenotype but not to germline variants.

Chronic gastritis and functional dyspepsia. Unity and struggle of two opposites

The review article describes the epidemiology, clinical picture, pathogenesis, approaches to the diagnosis and treatment of chronic gastritis and functional dyspepsia. Chronic gastritis is an unreasonably common diagnosis in our clinical practice, which is diagnosed in patients with disturbing dyspeptic complaints. According to the agreement documents, chronic gastritis is primarily a morphological concept. Chronic gastritis has no pathognomonic clinical signs and should be diagnosed during the histological examination of the gastric mucosa. Functional dyspepsia is a diagnosis that reflects the presence of a certain symptom complex (pain  or burning sensation in  the  epigastrium, a  feeling of  fullness or early satiety) in  the  absence of  diseases that could explain the symptoms. Secondary dyspepsia is diagnosed in patients with organic diseases of the upper gastrointestinal tract, metabolic or systemic diseases that cause dyspeptic syndrome. In the process of examining a patient with disturbing dyspeptic complaints, it is advisable for the doctor to use the diagnosis “unspecified dyspepsia” – a preliminary diagnosis before laboratory and instrumental examination aimed at identifying the cause of the dyspeptic syndrome. Dyspepsia associated with H. pylori is diagnosed in patients with H. pylori infection. The diagnosis is revised over time and is competent if complaints have been relieved within 6 months after effective H. pylori eradication.

The main drugs for the treatment of patients with dyspeptic complaints are proton pump inhibitors and prokinetics. Omeprazole with domperidone sustained release (SR) in a fixed dose combination is characterized by optimal efficacy and a good safety profile in patients with both functional and secondary dyspepsia and ensures a high level of treatment adherence.

Biliary reconstruction after choledochal cyst resection: a systematic review and meta-analysis on hepaticojejunostomy vs hepaticoduodenostomy

Choledochal cysts are a rare pediatric biliary pathology. Excision of the extrahepatic cyst and restoration of biliary-enteric continuity through either hepaticoduodenostomy (HD) or Roux-en-Y hepaticojejunostomy (HJ) is the mainstay treatment. This study aims to determine if either method provides an advantage. Following PRISMA guidelines, a systematic review was conducted, identifying studies comparing hepaticojejunostomy to hepaticoduodenostomy in patients with choledochal cysts. Data were analyzed using Review Manager 5.3. Nine studies were included, operative time was shorter - 97.50 [- 172.31, - 22.69] p = 0.01 and bleeding reduced - 48.98 [- 88.25, - 9.71] p = 0.01 in HD. HD was associated with shorter length of stay 2.18 [- 3.87, - 0.50] p = 0.01 and similar cholangitis and reintervention rates. Time to a normal diet was similar between groups. Biliary reflux was seen more frequently in HD 19.14 [2.60, 140.63] p = 0.004. Complications such as leak and cholangitis were similar between groups. HD represents a viable alternative to HJ with various advantages such as shorter operative time, decreased bleeding and shorter length of hospital stay. Bile reflux remains a major limitation.Level of evidence IV.

Bile acids increase intestinal marker expression via the FXR/SNAI2/miR-1 axis in the stomach

Purpose

Intestinal metaplasia (IM) is a precancerous lesion that increases the risk of subsequent gastric cancer (GC) development. Previously, miR-1 has been shown to play an essential role in the initiation of bile acid (BA)-induced IM. The objective of the present study was to investigate the mechanism underlying miR-1 inhibition by BA in gastric cells.

Methods

Ingenuity pathway analysis (IPA) was used to identify molecules acting upstream of miR-1. The effects of deoxycholic acid (DCA), FXR and SNAI2 on the expression of intestinal markers were assessed using quantitative real-time PCR (qRT-PCR) and Western blotting. The expression level of major molecules was detected by immunohistochemistry (IHC) in tissue microarrays. The transcriptional regulation of miR-1 was verified using luciferase reporter and chromatin immunoprecipitation (ChIP) assays.

Results

We found that BA treatment caused aberrant expression of FXR and intestinal markers in gastric cells. Augmented FXR led to transcriptional activation of SNAI2, which in turn suppressed the miR-1 promoter. Moreover, we found that compared with normal tissues, the expression levels of both FXR and SNAI2 were increased and positively correlated with each other in IM tissues. Additionally, their expression showed an inverse correlation with that of miR-1 in IM tissues.

Conclusions

Our findings indicate that FXR may be responsible for a series of molecular changes in gastric cells after BA treatment, and that the FXR/SNAI2/miR-1 axis exhibits a crucial role in BA-induced progression of IM. Blocking the FXR-oriented axis may provide a promising approach for IM or even GC treatment.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13402-021-00622-z.

Helicobacter pylori infection over bile reflux: No influence on the severity of endoscopic or premalignant gastric lesion development

Helicobacter (H.) pylori infection and duodenogastric reflux (DGR) are both linked to endoscopic and premalignant gastric lesion development, but it is still unclear whether they are independent or have a causal relationship. This study investigated the histologic gastric changes in patients with primary DGR and H. pylori infection, as well as their endoscopic findings, symptoms, drug consumption, and social behavior in comparison with patients presenting only DGR. The study included 560 patients with primary DGR on endoscopy divided into two groups, according to the presence/absence of H. pylori infection on biopsy (utilizing usual stainings and immunohistochemical methods). There was no significant difference in terms of age and sex, nor in the frequency of diabetes or esophagitis between the studied groups. Epigastric pain was associated with H. pylori-positive biopsies in multivariate logistic regression analysis (P=0.005). Although without statistical significance, severe endoscopic lesions and premalignant gastric lesions were more frequent in the H. pylori group (45.1 vs. 28.4% and 37.4 vs. 32.3%, respectively). In patients with DGR, the final multivariate model revealed a positive association between smoking and immunohistochemically confirmed H. pylori infection (P=0.02, OR=1.88, 95% confidence intervals (CI)=1.10 to 3.21), but a negative effect of proton pump inhibitor consumption (P<0.001, OR=0.50, 95% CI=0.35 to 0.73). In conclusion, in patients with H. pylori infection and DGR, epigastric pain was the main reason for the endoscopic investigation. H. pylori infection over DGR did not influence the severity of endoscopic or premalignant gastric lesion development. Furthermore, smoking is directly related to immunohistochemically assessed active H. pylori infection in patients with bile reflux.

Bile reflux is an independent risk factor for precancerous gastric lesions and gastric cancer: An observational cross-sectional study

OBJECTIVE

To identify whether bile reflux on endoscopy and other related variables are risk factors for precancerous gastric lesions and gastric cancer (GC).

METHODS

A multicenter, cross-sectional and observational study was conducted in five centers in China from June to October 2019, 1162 patients were recruited and divided into the chronic gastritis (CG), the precancerous lesion (low-grade intraepithelial neoplasia and intestinal metaplasia), and GC groups (including high-grade intraepithelial neoplasia). All participants underwent detailed interviews, endoscopy and biopsy, and completed questionnaires. Odds ratio and 95% confidence interval were calculated with multivariate logistic regression models with or without adjustment for Helicobacter pylori infection.

RESULTS

We recruited 668 patients with CG, 411 with precancerous lesions and 83 with GC. By comparing the CG and precancerous lesion groups, independent risk factors for cancerous gastric lesions were the grade of bile reflux, patient's age, dietary habits and family history of GC. Similar results were obtained when comparing the CG and GC groups. In addition, bile reflux was confirmed as an independent risk factor for progression from precancerous lesions to cancer.

CONCLUSIONS

Bile reflux on endoscopy as well as age, dietary habits and a family history of GC were independent risk factors for the development of precancerous gastric lesions and GC.

Inflammatory Cell Numbers in the Stomach of Japanese Subjects with Endoscopically Normal Mucosa without Helicobacter pylori Infection

INTRODUCTION

Since inflammatory cells, such as lymphocytes and plasma cells, normally inhabit the stomach, the border between normal and mild inflammation is difficult to visually determine using the updated Sydney system scale of gastritis. Additionally, eosinophils in the gastric mucosa must be counted to diagnose eosinophilic gastritis. We aimed to determine the normal number of inflammatory cells in patients with endoscopically normal mucosa and without Helicobacter pylori infections.

METHODS

We assessed patients aged 20-79 years, who had undergone upper gastrointestinal endoscopy at Kawasaki Medical School Hospital between January 2010 and December 2014. Inflammatory cells were counted in 1,000 μm2 fields of pyloric and fundic gland mucosal biopsy specimens. We finally included 325 (male, n = 141; female, n = 184; average age = 49.3 years) patients without inflammation who had H. pylori-negative endoscopic results and negative histological findings interpreted based on the updated Sydney System and the Kyoto classification of gastritis.

RESULTS

The average numbers of nucleated cells were 83.3 ± 14.2 and 65.4 ± 12.6/mm2 in the pyloric and fundic gland mucosae, respectively. Inflammatory cells were significantly more abundant in the pyloric mucosa than in the fundic gland mucosa (p < 0.05). Age and sex distribution did not significantly differ. Eosinophils were absent or scanty in the gastric mucosae of both glands in all patients.

CONCLUSION

We determined the absolute values of inflammatory cells, including eosinophils, in normal mucosae of pyloric and fundic glands. These findings could be important in defining gastric mucosal inflammation, including eosinophilic gastritis diagnosis.

Meta-Analysis Reveals the Prognostic Relevance of Nuclear and Membrane-Associated Bile Acid Receptors in Gastric Cancer

INTRODUCTION

Bile acids (BAs) arising from duodenogastric reflux are known to facilitate gastric cancer (GC) development. Although BAs traditionally contribute to carcinogenesis through direct cellular cytotoxicity, increasing evidence implicates nuclear and membrane BA receptors (BARs) as additional factors influencing cancer risk. Indeed, some BARs are already linked with GC, but conflicting evidence and lack of information regarding other endogenous BARs warrant further investigation. In this study, we meta-analyzed multiple data sets to identify clinically relevant relationships between BAR expression and prognosis, clinicopathology, and activity in GC.

METHODS

We collected transcriptomic data from the Gene Expression Omnibus and The Cancer Genome Atlas to analyze associations between BAR expression and GC prognosis, subtype, and clinicopathology. We also used Ingenuity Pathway Analysis to assess and predict functions, upstream regulators, and downstream mediators of membrane and nuclear BARs in GC.

RESULTS

BARs showed differential distribution in GC; membrane BARs (G protein-coupled BAR 1, sphingosine-1-phosphate receptor 2, and cholinergic receptor muscarinic 2) were enriched in diffuse-, genome-stable, and mesenchymal-type tumors, whereas nuclear BARs (pregnane-X-receptor, constitutive androstane receptor, and farnesoid-X-receptor) were enriched in chromosome instability and metabolic subtypes. High expression of all membrane but not nuclear BARs was associated with poor prognosis and unfavorable GC clinicopathologic features. Similarly, expression patterns of membrane but not nuclear BARs varied geographically, aligning with Helicobacter pylori infection and GC mortality rates. Finally, GC-related oncogenes, namely transforming growth factor β1, were associated with membrane BARs, whereas many metabolic-associated genes were associated with nuclear BARs.

DISCUSSION

Through transcriptomic meta-analysis, we identified distinct expression profiles between nuclear and membrane BARs that demonstrate prognostic relevance and warrant further investigation.

Synchronously Multiple Gastric Adenocarcinomas with Intestinal Mucin Phenotype in a Patient not Infected with Helicobacter pylori, Showing a Gastritis-like Appearance

Helicobacter pylori (H. pylori)-negative gastric cancer (HPNGC) usually shows a gastric mucin phenotype, but there are a few case reports of HPNGC with an intestinal mucin phenotype. We herein report a case of multiple HPNGC with an intestinal mucin phenotype showing a gastritis-like appearance. A 68-year-old H. pylori-uninfected man was suspected of having antral gastritis on endoscopy, but a histologic examination revealed multiple well-differentiated adenocarcinomas with positive-CDX2/MUC2/CD10 and negative-MUC5AC/MUC6. P53 was overexpressed, and intestinal metaplasia was sporadically detected in the non-atrophic mucosal background, thus indicating H. pylori-unrelated multistage carcinogenesis. The neoplastic surfaces were covered by a non-neoplastic epithelium, which caused a gastritis-like appearance. This report suggested the possibility of overlooking this neoplasm.

Caudal type homeoboxes as a driving force in Helicobacter pylori infection-induced gastric intestinal metaplasia

(H. pylori), a common pathogenic bacterium in the stomach, has been demonstrated to be a major cause of gastric cancer (GC). The typical pathological evolution of H. pylori infection-induced GC involves development from gastric atrophy, via intestinal metaplasia (IM) and dysplasia, to intestinal-type GC. During this process, IM is considered to be an "irreversible point" that significantly increases the risk for GC. Therefore, the elucidation of the mechanism underlying IM is of great significance for the prevention and treatment of gastric mucosal carcinogenesis associated with H. pylori infection. Caudal type homeoboxes (CDXs) are transcription factors involved in intestinal differentiation establishment and the maintenance of normal intestinal mucosa and IM. H. pylori infection increases the expression of CDXs through epigenetic regulation, the nuclear factor-kappaB signaling pathway and its downstream proinflammatory factors, and the transforming growth factor-beta signaling pathway, leading to the progression from normal gastric mucosa to IM. However, the precise mechanisms of gastric intestinal metaplasia have not yet been fully elucidated. In this review, we focus on research progress revealing the functions of CDXs in H. pylori infection-induced IM, as well as the regulators modulating this process.