Effect of Helicobacter pylori on gastrointestinal microbiota: a population-based study in Linqu, a high-risk area of gastric cancer

Microbiota-Gastric Cancer Interactions and the Potential Influence of Nutritional Therapies

Gastric cancer (GC) is one of the most common causes of cancer deaths, and GC treatments represent a large area of research. Although initially regarded as a sterile organ and unsuitable for microbial communities, the discovery of Helicobacter pylori made us realize that some microbes can colonize the stomach. In recent years, growing interest in gastric bacteria has expanded to the gut microbiota and, more recently, to the oral microbiota. Indeed, the oral-gastric-gut microbiota axis may play a crucial role in maintaining homeostasis, while changes in microbiota composition in GC patients can influence clinical outcomes. On the one hand, the microbiota and its metabolites may significantly influence the progression of GC, while anti-GC treatments such as gastrectomy and chemotherapy may significantly impact the oral-gastric-gut microbiota axis of GC patients. In this context, the role of nutritional therapies, including diet, prebiotics, and probiotics, in treating GC should not be underestimated. Wit this review, we aim to highlight the main role of the gastric, oral, and gut microbiota in GC onset and progression, representing potential future biomarkers for early GC detection and a target for efficient nutritional therapies during the course of GC.

Effects of Helicobacter pylori infection on intestinal microbiota, immunity and colorectal cancer risk

Infecting about half of the world´s population, Helicobacter pylori is one of the most prevalent bacterial infections worldwide and the strongest known risk factor for gastric cancer. Although H. pylori colonizes exclusively the gastric epithelium, the infection has also been associated with various extragastric diseases, including colorectal cancer (CRC). Epidemiological studies reported an almost two-fold increased risk for infected individuals to develop CRC, but only recently, direct causal and functional links between the chronic infection and CRC have been revealed. Besides modulating the host intestinal immune response, H. pylori is thought to increase CRC risk by inducing gut microbiota alterations. It is known that H. pylori infection not only impacts the gastric microbiota at the site of infection but also leads to changes in bacterial colonization in the distal large intestine. Considering that the gut microbiome plays a driving role in CRC, H. pylori infection emerges as a key factor responsible for promoting changes in microbiome signatures that could contribute to tumor development. Within this review, we want to focus on the interplay between H. pylori infection, changes in the intestinal microbiota, and intestinal immunity. In addition, the effects of H. pylori antibiotic eradication therapy will be discussed.

Update on the association between Helicobacter pylori infection and asthma in terms of microbiota and immunity

H. pylori is a gram-negative bacterium that is usually acquired in childhood and can persistently colonize the gastric mucosa of humans, affecting approximately half of the world's population. In recent years, the prevalence of H. pylori infection has steadily reduced while the risk of allergic diseases has steadily climbed. As a result, epidemiological research indicates a strong negative association between the two. Moreover, numerous experimental studies have demonstrated that eradicating H. pylori increases the risk of allergic diseases. Hence, it is hypothesized that H. pylori infection may act as a safeguard against allergic diseases. The hygiene hypothesis, alterations in gut microbiota, the development of tolerogenic dendritic cells, and helper T cells could all be involved in H. pylori's ability to protect against asthma. Furthermore, Studies on mice models have indicated that H. pylori and its extracts are crucial in the management of asthma. We reviewed the in-depth studies on the most recent developments in the relationship between H. pylori infection and allergic diseases, and we discussed potential mechanisms of the infection's protective effect on asthma in terms of microbiota and immunity. We also investigated the prospect of the application of H. pylori and its related components in asthma, so as to provide a new perspective for the prevention or treatment of allergic diseases.

Gastric microbiota in patients with gastric MALT lymphoma according to Helicobacter pylori infection

BACKGROUND

Gastric Mucosa Associated Lymphoid Tissue lymphoma (GML) development is triggered by Helicobacter pylori (H. pylori) infection. Little is known about the impact of H. pylori infection on gastric microbiota.

METHODS

The gastric microbiota was retrospectively investigated using 16S rRNA gene sequencing in 32 patients with untreated GML (10 H. pylori-positive and 22 H. pylori-negative), 23 with remitted and 18 refractory GML and 35 controls. Differences in microbial diversity, bacterial composition and taxonomic repartition were assessed.

RESULTS

There was no change in diversity and bacterial composition between GML and control patients taking into account H. pylori status. Differential taxa analysis identified specific changes associated with H. pylori-negative GML: the abundances of Actinobacillus, Lactobacillus and Chryseobacterium were increased while the abundances of Veillonella, Atopobium, Leptotrichia, Catonella, Filifactor and Escherichia_Shigella were increased in control patients. In patients with remitted GML, the genera Haemophilus and Moraxella were significantly more abundant than in refractory patients, while Atopobium and Actinomyces were significantly more abundant in refractory patients.

CONCLUSION

Detailed analysis of the gastric microbiota revealed significant changes in the bacterial composition of the gastric mucosa in patients with GML that may have a role in gastric lymphomagenesis but not any new pathobionts.

High expression of TRIP13 is associated with tumor progression in H. pylori infection induced gastric cancer

BACKGROUND/OBJECTIVE

H. pylori is a recognized bacterial carcinogen in the world to cause gastric cancer (GC). However, the molecular mechanism of H. pylori infection-induced GC is not completely clear. Thus, there is an urgent need to reveal the precise mechanisms regulating cancer development due to H. pylori infection.

METHODS

GEO microarray databases and TCGA databases were extracted for the analysis of different expression genes (DEGs). Then, Kaplan-Meier Plotter was used for prognostic analysis. Functional enrichment analysis of TRIP13 was performed by metascape database and TIMER database. Specific role of TRIP13 in GC with H. pylori infection was confirmed by CCK8, cell cycle analysis and WB.

RESULTS

A total 10 DEGs were substantially elevated in GC and H. pylori+ tissues and might be associated with H. pylori infection in GC and only the highly expressed TRIP13 was statistically associated with poor prognosis in GC patients. Meanwhile, TRIP13 were upregulated in both CagA-transfected epithelial cells and GC cells. And TRIP13 deficiency inhibited cell proliferation and arrested the cell cycle at the G1 phase.

CONCLUSION

Our study suggested that high expression of TRIP13 can promote the proliferation, cell cycle in GC cells, which could be used as a biomarker for H. pylori infection GC.

Comparison of Helicobacter pylori positive and negative gastric cancer via multi-omics analysis

IMPORTANCE

This is the first clinical research to systematically expound the difference between gastric cancer (GC) individuals with Helicobacter pylori and GC individuals without H. pylori from the perspective of multi-omics. This clinical study identified significant genes, microbes, and fecal metabolites, which exhibited nice power for differentiating GC individuals with H. pylori infection from GC individuals without H. pylori infection. This study provides a crucial basis for a better understanding of eradication therapy among the GC population.

Improvement of dyspeptic symptoms after Helicobacter pylori eradication therapy in Japanese patients

BACKGROUND AND AIM

Helicobacter pylori eradication therapy effectively improves the abdominal symptoms and bowel habits of patients. Patients in whom dyspepsia is under control by 6 to 12 months after successful H. pylori eradication are defined as having H. pylori-associated dyspepsia, and patients with dyspepsia that is refractory to successful eradication are defined as having functional dyspepsia. Here, we aimed to investigate the association between H. pylori eradication and improvement of dyspepsia in the short and long term after eradication therapy.

METHODS

Dyspeptic symptoms before treatment and at 2 and 12 months after eradication were evaluated using the Gastrointestinal Symptom Rating Scale (GSRS) in 282 H. pylori-positive Japanese patients who underwent eradication therapy.

RESULTS

Of the Japanese H. pylori-positive patients, 48.2% (136/282) had upper abdominal symptoms. Eradication improved dyspepsia in 34.5% (47/136) of the patients at 2 months post eradication, which continued to be under control up to 12 months. A significant decrease at 2 and 12 months after eradication, compared with before eradication, was observed in total GSRS (from 25.7 ± 10.4 [before eradication, n = 249] to 23.3 ± 7.2 [after 2 months, n = 249] and 24.8 ± 7.8 [after 12 months, n = 81]; P = 0.014 and 0.321, respectively), gastric pain score (from 4.1 ± 1.9 to 3.7 ± 1.3 and 3.7 ± 1.2; P = 0.025 and 0.047), and constipation score (from 5.9 ± 3.1 to 5.2 ± 2.3 and 5.9 ± 3.0; P < 0.021 and 0.862).

CONCLUSION

H. pylori-positive dyspepsia patients should be recommended to undergo H. pylori eradication to alleviate dyspepsia-associated symptoms.

Research trends on the relationship between Helicobacter pylori and microbiota: A bibliometric analysis

BACKGROUND

Increasing evidence has indicated that Helicobacter pylori infection is associated with the complex microbiota in the digestive tract of the human body. We aimed to assess the research trends and hotspots in the field of H. pylori and microbiota using a quantitative method.

MATERIALS AND METHODS

The clinical studies on H. pylori and microbiota published from 2001 to 2022 were extracted from the Web of Science database. We visualized and analyzed countries/regions, institutions, authors, journals, and keywords through VOSviewer and CiteSpace software. The test techniques, specimen type, as well as microbiota variation after H. pylori infection and eradication were also evaluated.

RESULTS

A total of 98 publications were finally identified, and the number of annual papers increased gradually. China showed its dominant position in the publication outputs, and Nanchang University was the most productive institution. Cong He, Xu Shu, and Yin Zhu published the highest number of papers, whereas Helicobacter was the most productive journal. "Helicobacter pylori" ranked highest in the keyword occurrences. 16S rRNA gene sequencing was the most frequently used method for microbiota analysis. Fecal samples had the highest frequency of use, followed by gastric mucosa and saliva. H. pylori infection was associated with the alterations of microbiota through the digestive tract, characterized by the enrichment of Helicobacter in the stomach. Triple and quadruple therapy were the most utilized eradication regimens, and probiotics supplementation therapy has been proven to reduce side effects and restore microbial diversity.

CONCLUSIONS

This bibliometric analysis provides an overview of advancements in the field of H. pylori and microbiota. While numerous studies have been conducted on the correlation between H. pylori and the alterations of microbiota, future research is warranted to investigate the mechanisms underlying the interplay between H. pylori and other microbes in the development of related diseases.

Gut virome profiling identifies an association between temperate phages and colorectal cancer promoted by Helicobacter pylori infection

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers worldwide. While a close correlation between chronic Helicobacter pylori infection and CRC has been reported, the role of the virome has been overlooked. Here, we infected Apc-mutant mouse models and C57BL/6 mice with H. pylori and conducted a comprehensive metagenomics analysis of H. pylori-induced changes in lower gastrointestinal tract bacterial and viral communities. We observed an expansion of temperate phages in H. pylori infected Apc+/1638N mice at the early stage of carcinogenesis. Some of the temperate phages were predicted to infect bacteria associated with CRC, including Enterococcus faecalis. We also observed a high prevalence of virulent genes, such as flgJ, cwlJ, and sleB, encoded by temperate phages. In addition, we identified phages associated with pre-onset and onset of H. pylori-promoted carcinogenesis. Through co-occurrence network analysis, we found strong associations between the viral and bacterial communities in infected mice before the onset of carcinogenesis. These findings suggest that the expansion of temperate phages, possibly caused by prophage induction triggered by H. pylori infection, may have contributed to the development of CRC in mice by interacting with the bacterial community.

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.

Diabetes Mellitus and Gastric Cancer: Correlation and Potential Mechanisms

This review summarizes the correlation between diabetes mellitus (DM) and gastric cancer (GC) from the perspectives of epidemiology, drug use, and potential mechanisms. The association between DM and GC is inconclusive, and the positive direction of the association reported in most published meta-analyses suggests that DM may be an independent risk factor for GC. Many clinical investigations have shown that people with DM and GC who undergo gastrectomy may have better glycemic control. The potential link between DM and GC may involve the interaction of multiple common risk factors, such as obesity, hyperglycemia and hyperinsulinemia, H. pylori infection, and the use of metformin. Although in vitro and in vivo data support that H. pylori infection status and metformin can influence GC risk in DM patients, there are conflicting results. Patient survival outcomes are influenced by multiple factors, so further research is needed to identify the patients who may benefit.

Control of Helicobacter pylori with engineered probiotics secreting selective guided antimicrobial peptides

Helicobacter pylori is the primary cause of 78% of gastric cancer cases, providing an opportunity to prevent cancer by controlling a single bacterial pathogen within the complex gastric microbiota. We developed highly selective antimicrobial agents against H. pylori by fusing an H. pylori-binding guide peptide (MM1) to broad-spectrum antimicrobial peptides. The common dairy probiotic Lactococcus lactis was then engineered to secrete these guided antimicrobial peptides (gAMPs). When co-cultured in vitro with H. pylori, the gAMP probiotics lost no toxicity compared to unguided AMP probiotics against the target, H. pylori, while losing >90% of their toxicity against two tested off-target bacteria. To test binding to H. pylori, the MM1 guide was fused to green fluorescent protein (GFP), resulting in enhanced binding compared to unguided GFP as measured by flow cytometry. In contrast, MM1-GFP showed no increased binding over GFP against five different off-target bacteria. These highly selective gAMP probiotics were then tested by oral gavage in mice infected with H. pylori. As a therapy, the probiotics outperformed antibiotic treatment, effectively eliminating H. pylori in just 5 days, and also protected mice from challenge infection as a prophylactic. As expected, the gAMP probiotics were as toxic against H. pylori as the unguided AMP probiotics. However, a strong rebound in gastric species diversity was found with both the selective gAMP probiotics and the non-selective AMP probiotics. Eliminating the extreme microbial dysbiosis caused by H. pylori appeared to be the major factor in diversity recovery. IMPORTANCE Alternatives to antibiotics in the control of Helicobacter pylori and the prevention of gastric cancer are needed. The high prevalence of H. pylori in the human population, the induction of microbial dysbiosis by antibiotics, and increasing antibiotic resistance call for a more sustainable approach. By selectively eliminating the pathogen and retaining the commensal community, H. pylori control may be achieved without adverse health outcomes. Antibiotics are typically used as a therapeutic post-infection, but a more targeted, less disruptive approach could be used as a long-term prophylactic against H. pylori or, by extension, against other gastrointestinal pathogens. Furthermore, the modular nature of the guided antimicrobial peptide (gAMP) technology allows for the substitution of different guides for different pathogens and the use of a cocktail of gAMPs to avoid the development of pathogen resistance.

Efficacy and safety of Lacticaseibacillus rhamnosus R0011 and Lactobacillus helveticus R0052 as an adjuvant for Helicobacter pylori eradication: a double-blind, randomized, placebo-controlled study

Background

Helicobacter pylori eradication is recommended as a way of providing symptomatic relief for dyspepsia. The limited efficacy of triple therapy is a major problem in many countries, including Thailand. Some probiotics have been shown to improve the H. pylori eradication rate and reduce side effects. This study aimed at evaluating the efficacy of probiotic (Lacidofil® STRONG) as adjuvant to standard triple therapy.

Methods

This randomized, double-blind, placebo-controlled study was conducted between July 2020 and June 2022. Eligible patients with H. pylori gastritis (i.e., n=90 out of the 160 patients screened) were randomized to receive 14-day standard triple therapy either with probiotics or with a placebo (N=45/group). The treatment regimen entailed 30 mg lansoprazole administered twice daily, 1,000 mg amoxicillin administered twice daily, and 1 g clarithromycin modified-release formulation administered once daily. A probiotic capsule containing Lacticaseibacillus rhamnosus R0011 and Lactobacillus helveticus R0052 (Lacidofil® STRONG) or placebo were given twice daily during the eradication therapy and for an additional 4 weeks. Successful H. pylori eradication was defined as a negative 13C-urea breath test at least 4 weeks after complete eradication.

Results

As per-protocol analysis, eradication rates after the 14-day regimen with probiotic or placebo were 90.9% and 75.0% (p=0.047), respectively. Antibiotic susceptibility testing demonstrated high clarithromycin resistance (24%). For clarithromycin-resistant strains, there was no statistical difference in eradication rates between the probiotic and placebo groups. Furthermore, probiotic supplementation significantly reduced treatment side effects, including bloating (OR 0.27 [95% CI 0.10 to 0.75], p=0.012), diarrhea (OR 0.23 [95% CI 0.28 to 0.65], p=0.006), nausea (OR 0.05 [95% CI 0.01 to 0.36], p=0.003), and bitter taste (OR 0.14 [95% CI 0.03 to 0.69], p=0.015). In addition, the probiotic group had lower gastrointestinal symptom rating scale (GSRS) scores (1.46 ± 0.36 vs. 2.65 ± 0.66, p&lt;0.001) and higher SF-36 health-related quality-of-life scores (63.3 ± 10.2 vs. 57.3 ± 13.4, p=0.020) after treatment than the placebo group.

Conclusion

The probiotic adjuvant with 14-day standard triple therapy improved the H. pylori eradication rate. Supplementation with Lacidofil® STRONG during the 2-week eradication treatment and 4-week follow-up phase can help to reduce the gastrointestinal side effects of eradication therapy and increase patients’ general health-related quality of life.

Influence of Helicobacter pylori infection on risk of rheumatoid arthritis: a nationwide population-based study

The relationship between Helicobacter pylori infection and rheumatoid arthritis has been investigated, but the results remain controversial. This study aims to determine the association between the two diseases via a 17-year retrospective cohort study. Using the National Health Insurance Research Database, a nationwide population based in Taiwan, we identified 97,533 individuals with H. pylori infection and matched controls between 2000 and 2017 using propensity score matching at a 1:1 ratio. The adjusted hazard ratio of rheumatoid arthritis was determined by multiple Cox regression. The incidence rate of rheumatoid arthritis was 1.28 per 10,000 person-months in the H. pylori cohort, with a higher risk compared to the control group. In the < 30 years old subgroup, the risk was highest, especially in women < 30 years old with H. pylori infection. Patients with < 1 year follow-up showed 1.58 times higher susceptibility to rheumatoid arthritis. Individuals with follow-ups of 1-5 years and over 5 years demonstrated 1.43 and 1.44 times higher risks of rheumatoid arthritis, respectively. Our study showed H. pylori infection was associated with the development of rheumatoid arthritis. Clinicians should note higher risk, especially < 30 years old. More research needed to understand underlying mechanism.

Crosstalk between Helicobacter pylori and gastrointestinal microbiota in various gastroduodenal diseases-A systematic review

Gastroduodenal diseases have prevailed for a long time and more so due to dominance of gut bacteria Helicobacter pylori in most of the cases. But habitation by other gut microbiota in gastroduodenal diseases and the relationship between Helicobacter pylori and gastrointestinal microbiota in different gastroduodenal diseases is somewhat being unravelled in the current times. For this systematic review, we did a literature search of various gastroduodenal diseases and the effect on gut microbiota pertaining to it. A search of the online bibliographic databases PUBMED and PUBMED CENTRAL was carried out to identify articles published between 1977 and May 2022. The analysis of these selected studies highlighted the inhabitation of other gut microbiota such as Fusobacteria, Bacteroidetes, Streptococcaceae, Prevotellaceae, Fusobacteriaceae, and many others. Interplay between these microbiota and H. pylori have also been noted which suggested that gastroduodenal diseases and gut microbiota are intertwined by a symbiotic association regardless of the H. pylori status. The relationship between the gut microbiota and many gastroduodenal diseases, such as gastritis, gastric cancer, lymphomas, and ulcers, demonstrates the dysbiosis of the gut microbiota in both the presence and absence of H. pylori. The evolving ways for eliminating H. pylori are provided along with inhibiting qualities of other species on H. pylori. Most significant member of our gut system is Helicobacter pylori which has been associated with numerous diseases like gastric cancer, gastritis, duodenal ulcer.

Development of Gut Microbiota in the First 1000 Days after Birth and Potential Interventions

The first 1000 days after birth represent a critical window for gut microbiome development, which is essential for immune system maturation and overall health. The gut microbiome undergoes major changes during this period due to shifts in diet and environment. Disruptions to the microbiota early in life can have lasting health effects, including increased risks of inflammatory disorders, autoimmune diseases, neurological disorders, and obesity. Maternal and environmental factors during pregnancy and infancy shape the infant gut microbiota. In this article, we will review how maintaining a healthy gut microbiome in pregnancy and infancy is important for long-term infant health. Furthermore, we briefly include fungal colonization and its effects on the host immune function, which are discussed as part of gut microbiome ecosystem. Additionally, we will describe how potential approaches such as hydrogels enriched with prebiotics and probiotics, gut microbiota transplantation (GMT) during pregnancy, age-specific microbial ecosystem therapeutics, and CRISPR therapies targeting the gut microbiota hold potential for advancing research and development. Nevertheless, thorough evaluation of their safety, effectiveness, and lasting impacts is crucial prior to their application in clinical approach. The article emphasizes the need for continued research to optimize gut microbiota and immune system development through targeted early-life interventions.

Metabolite Alterations and Interactions with Microbiota in Helicobacter pylori-Associated Gastric Lesions

Metabolites and their interactions with microbiota may be involved in Helicobacter pylori-associated gastric lesion development. This study aimed to explore metabolite alterations upon H. pylori eradication and possible roles of microbiota-metabolite interactions in progression of precancerous lesions. Targeted metabolomics assays and 16S rRNA gene sequencing were conducted to investigate metabolic and microbial alterations of paired gastric biopsy specimens in 58 subjects with successful and 57 subjects with failed anti-H. pylori treatment. Integrative analyses were performed by combining the metabolomics and microbiome profiles from the same intervention participants. A total of 81 metabolites were significantly altered after successful eradication compared to failed treatment, including acylcarnitines, ceramides, triacylglycerol, cholesterol esters, fatty acid, sphingolipids, glycerophospholipids, and glycosylceramides, with P values of <0.05 for all. The differential metabolites showed significant correlations with microbiota in baseline biopsy specimens, such as negative correlations between Helicobacter and glycerophospholipids, glycosylceramide, and triacylglycerol (P < 0.05 for all), which were altered by eradication. The characteristic negative correlations between glycosylceramides and Fusobacterium, Streptococcus, and Gemella in H. pylori-positive baseline biopsy specimens were further noticed in active gastritis and intestinal metaplasia (P < 0.05 for all). A panel including differential metabolites, genera, and their interactions may help to discriminate high-risk subjects who progressed from mild to advanced precancerous lesions in short-term and long-term follow-up periods with areas under the curve (AUC) of 0.914 and 0.801, respectively. Therefore, our findings provide new insights into the metabolites and microbiota interactions in H. pylori-associated gastric lesion progression. IMPORTANCE In this study, a panel was established including differential metabolites, genera, and their interactions, which may help to discriminate high-risk subjects for progression from mild lesions to advanced precancerous lesions in short-term and long-term follow-up.

The burden of stomach cancer mortality by county, race, and ethnicity in the USA, 2000-2019: a systematic analysis of health disparities

Background

There are persistent disparities in stomach cancer mortality among racial-ethnic groups in the USA, but the extent to which these patterns vary geographically is not well understood. This analysis estimated age-standardised mortality for five racial-ethnic groups, in 3110 USA counties over 20 years, to describe spatial-temporal variations in stomach cancer mortality and disparities between racial-ethnic groups.

Methods

Redistribution methods for insufficient cause of death codes and validated small area estimation methods were applied to death registration data from the US National Vital Statistics System and population data from the US National Center for Health Statistics to estimate annual stomach cancer mortality rates. Estimates were stratified by county and racial-ethnic group (non-Latino and non-Hispanic [NL] American Indian or Alaska Native [AIAN], NL Asian or Pacific Islander [Asian], NL Black [Black], Latino or Hispanic [Latino], and NL White [White]) from 2000 to 2019. Estimates were corrected for misreporting of racial-ethnic group on death certificates using published misclassification ratios. We masked (ie, did not display) estimates for county and racial-ethnic group combinations with a mean annual population of less than 1000; thus, we report estimates for 3079 (of 3110) counties for the total population, and 474, 667, 1488, 1478, and 3051 counties for the AIAN, Asian, Black, Latino, and White populations, respectively.

Findings

Between 2000 and 2019, national age-standardised stomach cancer mortality was lowest among the White population in every year. Nationally, stomach cancer mortality declined for all racial-ethnic groups across this time period, with the most rapid declines occurring among the Asian (percent decline 48.3% [45.1-51.1]) and Black populations (42.6% [40.2-44.6]). Mortality among the other racial-ethnic groups declined more moderately, decreasing by 36.7% (35.3-38.1), 35.1% (32.2-37.7), and 31.6% (23.9-38.0) among the White, Latino, and AIAN populations, respectively. Similar patterns were observed at the county level, although with wide geographic variation. In 2019, a majority of counties had higher mortality rates among minoritised racial-ethnic populations compared to the White population: 81.1% (377 of 465 counties with unmasked estimates for both racial-ethnic groups) among the AIAN population, 88.2% (1295 of 1469) among the Latino population, 99.4% (663 of 667) among the Asian population, and 99.9% (1484 of 1486) among the Black population. However, the size of these disparities ranged widely across counties, with the largest range from 0.3 to 17.1 among the AIAN population.

Interpretation

Stomach cancer mortality has decreased substantially across populations and geographies in the USA. However, disparities in stomach cancer mortality among racial-ethnic groups are widespread and have persisted over the last two decades. Local-level data are crucial to understanding the scope of this unequal burden among minoritised groups in the USA.

Funding

National Institute on Minority Health and Health Disparities; National Heart, Lung, and Blood Institute; National Cancer Institute; National Institute on Aging; National Institute of Arthritis and Musculoskeletal and Skin Diseases; Office of Disease Prevention; and Office of Behavioral and Social Sciences Research, National Institutes of Health (contract #75N94019C00016).

Integrated analysis of the microbiome and transcriptome in stomach adenocarcinoma

We aimed to characterize the stomach adenocarcinoma (STAD) microbiota and its clinical value using an integrated analysis of the microbiome and transcriptome. Microbiome and transcriptome data were downloaded from the Cancer Microbiome Atlas and the Cancer Genome Atlas databases. We identified nine differentially abundant microbial genera, including Helicobacter, Mycobacterium, and Streptococcus, which clustered patients into three subtypes with different survival rates. In total, 74 prognostic genes were screened from 925 feature genes of the subtypes, among which five genes were identified for prognostic model construction, including NTN5, MPV17L, MPLKIP, SIGLEC5, and SPAG16. The prognostic model could stratify patients into different risk groups. The high-risk group was associated with poor overall survival. A nomogram established using the prognostic risk score could accurately predict the 1, 3, and 5 year overall survival probabilities. The high-risk group had a higher proportion of histological grade 3 and recurrence samples. Immune infiltration analysis showed that samples in the high-risk group had a higher abundance of infiltrating neutrophils. The Notch signaling pathway activity showed a significant difference between the high- and low-risk groups. In conclusion, a prognostic model based on five feature genes of microbial subtypes could predict the overall survival for patients with STAD.

Efficacy analysis of empirical bismuth quadruple therapy, high-dose dual therapy, and resistance gene-based triple therapy as a first-line Helicobacter pylori eradication regimen - An open-label, randomized trial

This research aimed to evaluate the eradication efficacy, safety, and gastrointestinal symptom relief rates of empirical bismuth quadruple therapy, high-dose dual therapy, and resistance gene-based triple therapy in primary eradication patients in Yangzhou, China. It also investigated the possible factors influencing the success of different Helicobacter pylori eradication regimens. A single-center, prospective, open-label, randomized controlled study was performed from December 2020 and October 2021, in which 255 patients with H. pylori infection were assigned in a 1:1:1 ratio to the three different groups. Our results showed that high-dose dual therapy (91.0%, 71/78) and resistance gene-based triple therapy (94.9%, 75/79) achieved eradication rates and compliance equivalent to those of empirical bismuth quadruple therapy (85.3%, 64/75) in the per-protocol analysis, while high-dose dual therapy had lower rates of adverse events (11.5%, 9/78, P < 0.05), fewer side effects, and greater safety. Most patients' gastrointestinal discomfort symptoms improved after eradication of H. pylori. Poor compliance (P < 0.05) and antibiotic resistance (P < 0.05) were risk factors for the efficacy of H. pylori eradication. Therefore, the appropriate regimen can be individualized for eradication therapy in clinical practice according to the patient's resistance and tolerance to the drug.

The role of the gut microbiota in gastric cancer: the immunoregulation and immunotherapy

Gastric cancer (GC) is one of the most common cancers, leading to the deaths of millions of people worldwide. Therefore, early detection and effective therapeutic strategies are of great value for decreasing the occurrence of advanced GC. The human microbiota is involved not only in the maintenance of physiological conditions, but also in human diseases such as obesity, diabetes, allergic and atopic diseases, and cancer. Currently, the composition of the bacteria in the host, their functions, and their influence on disease progression and treatment are being discussed. Previous studies on the gut microbiome have mostly focused on Helicobacter pylori (Hp) owing to its significant role in the development of GC. Nevertheless, the enrichment and diversity of other bacteria that can modulate the tumor microenvironment are involved in the progression of GC and the efficacy of immunotherapy. This review provides systematic insight into the components of the gut microbiota and their application in GC, including the specific bacteria of GC, their immunoregulatory effect, and their diagnostic value. Furthermore, we discuss the relationship between the metabolism of microbes and their potential applications, which may serve as a new approach for the diagnosis and treatment of GC.

NF-κB in Cell Deaths, Therapeutic Resistance and Nanotherapy of Tumors: Recent Advances

The transcription factor nuclear factor-κB (NF-κB) plays a complicated role in multiple tumors. Mounting evidence demonstrates that NF-κB activation supports tumorigenesis and development by enhancing cell proliferation, invasion, and metastasis, preventing cell death, facilitating angiogenesis, regulating tumor immune microenvironment and metabolism, and inducing therapeutic resistance. Notably, NF-κB functions as a double-edged sword exerting positive or negative influences on cancers. In this review, we summarize and discuss recent research on the regulation of NF-κB in cancer cell deaths, therapy resistance, and NF-κB-based nano delivery systems.

Role of the gut microbiota in anticancer therapy: from molecular mechanisms to clinical applications

In the past period, due to the rapid development of next-generation sequencing technology, accumulating evidence has clarified the complex role of the human microbiota in the development of cancer and the therapeutic response. More importantly, available evidence seems to indicate that modulating the composition of the gut microbiota to improve the efficacy of anti-cancer drugs may be feasible. However, intricate complexities exist, and a deep and comprehensive understanding of how the human microbiota interacts with cancer is critical to realize its full potential in cancer treatment. The purpose of this review is to summarize the initial clues on molecular mechanisms regarding the mutual effects between the gut microbiota and cancer development, and to highlight the relationship between gut microbes and the efficacy of immunotherapy, chemotherapy, radiation therapy and cancer surgery, which may provide insights into the formulation of individualized therapeutic strategies for cancer management. In addition, the current and emerging microbial interventions for cancer therapy as well as their clinical applications are summarized. Although many challenges remain for now, the great importance and full potential of the gut microbiota cannot be overstated for the development of individualized anti-cancer strategies, and it is necessary to explore a holistic approach that incorporates microbial modulation therapy in cancer.

The role of bismuth nanoparticles in the inhibition of bacterial infection

Bismuth (Bi) combinations have been utilized for the treatment of bacterial infections. In addition, these metal compounds are most frequently utilized for treating gastrointestinal diseases. Usually, Bi is found as bismuthinite (Bi sulfide), bismite (Bi oxide), and bismuthite (Bi carbonate). Newly, Bi nanoparticles (BiNP) were produced for CT imaging or photothermal treatment and nanocarriers for medicine transfer. Further benefits, such as increased biocompatibility and specific surface area, are also seen in regular-size BiNPs. Low toxicity and ecologically favorable attributes have generated interest in BiNPs for biomedical approaches. Moreover, BiNPs offer an option for treating multidrug-resistant (MDR) bacteria because they communicate directly with the bacterial cell wall, induce adaptive and inherent immune reactions, generate reactive oxygen compounds, limit biofilm production, and stimulate intracellular impacts. In addition, BiNPs in amalgamation with X-ray therapy as well as have the capability to treat MDR bacteria. BiNPs as photothermal agents can realize the actual antibacterial through continuous efforts of investigators in the near future. In this article, we summarized the properties of BiNPs, and different preparation methods, also reviewed the latest advances in the BiNPs' performance and their therapeutic effects on various bacterial infections, such as Helicobacter pylori, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli.

Long-term effect of Helicobacter pylori eradication on colorectal cancer incidences

Background

There is evidence supporting the association between Helicobacter pylori infection and colorectal cancer (CRC), but whether H. pylori eradication reduces the risk of CRC is still unknown.

Objectives

To compare the incidence of CRC in subjects who had received H. pylori eradication therapy with general population.

Design

A population-based retrospective cohort study.

Methods

This study included all H. pylori-infected subjects who had received their first course of clarithromycin-containing triple therapy in 2003-2015 in Hong Kong. We compared the observed incidences of CRC in this H. pylori eradicated cohort with the expected incidences in the age- and sex-matched general population. The standardized incidence ratio (SIR) with 95% confidence interval (CI) was computed.

Results

Among 96,572 H. pylori-eradicated subjects with a median follow-up of 9.7 years, 1417 (1.5%) developed CRC. Primary analysis showed no significant difference in the observed and expected incidences of CRC (SIR: 1.03, 95% CI: 0.97-1.09). However, when stratified according to the follow-up period, higher incidence of CRC was only observed in the first 5 years after eradication (SIR: 1.47, 95% CI: 1.39-1.55), but it was lower (SIR: 0.85, 95% CI: 0.74-0.99) than general population after 11 years. When stratified by tumor location, the observed incidence was higher for colon (SIR: 1.20, 95% CI: 1.12-1.29) but lower for rectal cancer (SIR: 0.90, 95% CI: 0.81-0.999) among H. pylori-eradicated subjects.

Conclusions

H. pylori-infected subjects appeared to have a higher incidence of CRC initially, which declined progressively to a level lower than general population 10 years after H. pylori eradication, particularly for rectal cancer.

Helicobacter pylori infection

Helicobacter pylori infection causes chronic gastritis, which can progress to severe gastroduodenal pathologies, including peptic ulcer, gastric cancer and gastric mucosa-associated lymphoid tissue lymphoma. H. pylori is usually transmitted in childhood and persists for life if untreated. The infection affects around half of the population in the world but prevalence varies according to location and sanitation standards. H. pylori has unique properties to colonize gastric epithelium in an acidic environment. The pathophysiology of H. pylori infection is dependent on complex bacterial virulence mechanisms and their interaction with the host immune system and environmental factors, resulting in distinct gastritis phenotypes that determine possible progression to different gastroduodenal pathologies. The causative role of H. pylori infection in gastric cancer development presents the opportunity for preventive screen-and-treat strategies. Invasive, endoscopy-based and non-invasive methods, including breath, stool and serological tests, are used in the diagnosis of H. pylori infection. Their use depends on the specific individual patient history and local availability. H. pylori treatment consists of a strong acid suppressant in various combinations with antibiotics and/or bismuth. The dramatic increase in resistance to key antibiotics used in H. pylori eradication demands antibiotic susceptibility testing, surveillance of resistance and antibiotic stewardship.

The Influence of Helicobacter pylori on Human Gastric and Gut Microbiota

Helicobacter pylori is a Gram-negative bacterium that is able to colonize the human stomach, whose high prevalence has a major impact on human health, due to its association with several gastric and extra-gastric disorders, including gastric cancer. The gastric microenvironment is deeply affected by H. pylori colonization, with consequent effects on the gastrointestinal microbiota, exerted via the regulation of various factors, including gastric acidity, host immune responses, antimicrobial peptides, and virulence factors. The eradication therapy required to treat H. pylori infection can also have detrimental consequences for the gut microbiota, leading to a decreased alpha diversity. Notably, therapy regimens integrated with probiotics have been shown to reduce the negative effects of antibiotic therapy on the gut microbiota. These eradication therapies combined with probiotics have also higher rates of eradication, when compared to standard treatments, and are associated with reduced side effects, improving the patient's compliance. In light of the deep impact of gut microbiota alterations on human health, the present article aims to provide an overview of the complex interaction between H. pylori and the gastrointestinal microbiota, focusing also on the consequences of eradication therapies and the effects of probiotic supplementation.

NLRP3 inflammasome-induced pyroptosis in digestive system tumors

Programmed cell death (PCD) refers to cell death in a manner that depends on specific genes encoding signals or activities. PCD includes apoptosis, pyroptosis, autophagy and necrosis (programmed necrosis). Among these mechanisms, pyroptosis is mediated by the gasdermin family and is accompanied by inflammatory and immune responses. When pathogens or other danger signals are detected, cytokine action and inflammasomes (cytoplasmic multiprotein complexes) lead to pyroptosis. The relationship between pyroptosis and cancer is complex and the effect of pyroptosis on cancer varies in different tissue and genetic backgrounds. On the one hand, pyroptosis can inhibit tumorigenesis and progression; on the other hand, pyroptosis, as a pro-inflammatory death, can promote tumor growth by creating a microenvironment suitable for tumor cell growth. Indeed, the NLRP3 inflammasome is known to mediate pyroptosis in digestive system tumors, such as gastric cancer, pancreatic ductal adenocarcinoma, gallbladder cancer, oral squamous cell carcinoma, esophageal squamous cell carcinoma, in which a pyroptosis-induced cellular inflammatory response inhibits tumor development. The same process occurs in hepatocellular carcinoma and some colorectal cancers. The current review summarizes mechanisms and pathways of pyroptosis, outlining the involvement of NLRP3 inflammasome-mediated pyroptosis in digestive system tumors.

Helicobacter pylori promotes colorectal carcinogenesis by deregulating intestinal immunity and inducing a mucus-degrading microbiota signature

OBJECTIVE

Helicobacter pylori infection is the most prevalent bacterial infection worldwide. Besides being the most important risk factor for gastric cancer development, epidemiological data show that infected individuals harbour a nearly twofold increased risk to develop colorectal cancer (CRC). However, a direct causal and functional connection between H. pylori infection and colon cancer is lacking.

DESIGN

We infected two Apc-mutant mouse models and C57BL/6 mice with H. pylori and conducted a comprehensive analysis of H. pylori-induced changes in intestinal immune responses and epithelial signatures via flow cytometry, chip cytometry, immunohistochemistry and single cell RNA sequencing. Microbial signatures were characterised and evaluated in germ-free mice and via stool transfer experiments.

RESULTS

H. pylori infection accelerated tumour development in Apc-mutant mice. We identified a unique H. pylori-driven immune alteration signature characterised by a reduction in regulatory T cells and pro-inflammatory T cells. Furthermore, in the intestinal and colonic epithelium, H. pylori induced pro-carcinogenic STAT3 signalling and a loss of goblet cells, changes that have been shown to contribute-in combination with pro-inflammatory and mucus degrading microbial signatures-to tumour development. Similar immune and epithelial alterations were found in human colon biopsies from H. pylori-infected patients. Housing of Apc-mutant mice under germ-free conditions ameliorated, and early antibiotic eradication of H. pylori infection normalised the tumour incidence to the level of uninfected controls.

CONCLUSIONS

Our studies provide evidence that H. pylori infection is a strong causal promoter of colorectal carcinogenesis. Therefore, implementation of H. pylori status into preventive measures of CRC should be considered.

Cancer Progress and Priorities: Gastric Cancer

Gastric cancer, the fifth leading cause of cancer worldwide, is estimated to be responsible for approximately 1.4% of all new cancers and 1.8% of all cancer-related deaths in the United States. Despite declining incidence rates and improved survival rates, however, gastric cancer continues to disproportionately affect racial and ethnic minorities and individuals of lower socioeconomic status at higher rates than the general population. To improve outcomes globally and address disparities within the United States, continued improvements are needed in risk factor modification and biomarker development and to improve access to existing preventative measures such as genetic testing and H. pylori eradication testing, in addition to expanding upon current clinical guidelines for premalignant disease to address gaps in endoscopic surveillance and early detection.

Controlling Gastric Cancer in a World of Heterogeneous Risk

Gastric cancer (GC) is a leading cause of global mortality but also a cancer whose footprint is highly unequal. This review aims to define global disease epidemiology, critically appraise strategies of prevention and disease attenuation, and assess how these strategies could be applied to improve outcomes from GC in a world of variable risk and disease burden. Strategies of primary prevention focus on improving the detection and eradication of the main environmental risk factor, Helicobacter pylori. In certain countries of high incidence, endoscopic or radiographic screening of the asymptomatic general population has been adopted as a means of secondary prevention. By contrast, identification and targeted surveillance of individuals with precancerous lesions (such as intestinal metaplasia) is being increasingly embraced in nations of low incidence. This review also highlights existing knowledge gaps in GC prevention as well as the role of emerging technologies for early detection and risk stratification.

Dysbiosis of gut microbiota due to diet, alcohol intake, body mass index, and gastrointestinal diseases in India

The human gut is composed of diverse microflora which is influenced by dietary intake. Body mass index (BMI) and lifestyle patterns also play a vital role in human health to alter gut microbial composition. Our study aims to determine the impact of alcohol intake, BMI, and diet on gut microbiota and its relationship with gastrointestinal disorders. Thirty-nine gastric biopsies were taken from patients with various gastrointestinal (GI) diseases, and all the patient's lifestyle behavior were recorded in a written proforma. 16S rRNA metagenome analysis for V3-V4 regions was used to examine microbial compositions. The richness and diversity of gut microbiota were analyzed by PERMANOVA using the Bray-Curtis dissimilarity index and principal component analysis. The difference in relative abundance was calculated by ANOVA (p < 0.05). Alpha diversity indexes between vegetarians and non-vegetarians showed no significant difference based on BMI, alcohol status, and GI diseases. We found that in overweight vegetarian individuals Faecalibacterium and Rumicococcus might play a role in the control of Helicobacter pylori. Similarly, the increased abundance of Akkermansia muciniphila in non-vegetarian individuals with normal BMI might play a role to decrease the level of harmful bacteria like H. pylori, and Corynebacterium sp. Also, the relative abundance of Corynebacterium sp. among the vegetarians and Streptococcus sp. in the non-vegetarians was increased in alcoholics while H. pylori was increased in non-alcoholics irrespective of diet. There is an increased abundance of Faecalibacterium prausnitzii in vegetarians among all categories; however, we did not find any correlation between disease outcomes. Our study shows that alcohol intake and dietary habits have independent effects on gut microbial composition. The relative abundance of F. prausnitzii was high among vegetarians in all categories. KEY POINTS: • The presence of H. pylori is less among alcoholics. • Good bacteria help to maintain a normal body mass index. • Gut microbiota richness is high in vegetarians and diversity in non-vegetarians.

Non-Helicobacter pylori Gastric Microbiome Modulates Prooncogenic Responses and Is Associated With Gastric Cancer Risk

Background and Aims

Although Helicobacter pylori is the most important bacterial carcinogen in gastric cancer (GC), GC can emerge even after H. pylori eradication. Studies suggest that various constituents of the gastric microbiome may influence GC development, but the role of individual pathogens is unclear.

Methods

Human gastric mucosal samples were analyzed by 16SrRNA sequencing to investigate microbiome composition and its association with clinical parameters, including GC risk. Identified bacteria in the stomach were cocultured with gastric epithelial cells or inoculated into mice, and transcriptomic changes, DNA damage, and inflammation were analyzed. Bacterial reads in GC tissues were examined together with transcriptomic and genetic sequencing data in the cancer genome atlas dataset.

Results

Patients after Helicobacter pylori eradication formed 3 subgroups based on the microbial composition revealed by 16SrRNA sequencing. One dysbiotic group enriched with Fusobacterium and Neisseria species was associated with a significantly higher GC incidence. These species activated prooncogenic pathways in gastric epithelial cells and promoted inflammation in mouse stomachs. Sugar chains that constitute gastric mucin attenuate host-bacteria interactions. Metabolites from Fusobacterium species were genotoxic, and the presence of the bacteria was associated with an inflammatory signature and a higher tumor mutation burden.

Conclusion

Gastric microbiota in the dysbiotic stomach is associated with GC development after H. pylori eradication and plays a pathogenic role through direct host-bacteria interaction.

Microbiome and function alterations in the gastric mucosa of asymptomatic patients with Helicobacter pylori infection

BACKGROUND

Most patients with Helicobacter pylori (H. pylori) infection have no clinical symptoms, numerous studies reported the gastric microbiome in H. pylori-infected patients, but asymptomatic patients have not been distinguished. How the microbiome and function changes in asymptomatic patients with H. pylori infection remains poorly understood.

METHODS

A total of 29 patients were divided into H. pylori-infected asymptomatic group (10 patients), H. pylori-infected symptomatic group (11 patients) and H. pylori-uninfected group (8 patients). Gastric mucosa specimens were taken for histopathological examination, special staining, and 16 S rDNA sequencing. High-throughput results were evaluated by community composition analysis, indicator species analysis, alpha diversity analysis, beta diversity analysis, and function prediction.

RESULTS

The gastric microbiota composition at phylum and genus level of H. pylori-infected asymptomatic patients were similar with H. pylori-infected symptomatic group, but different from H. pylori-uninfected patients. The diversity and richness of gastric microbial community declined significantly in H. pylori-infected asymptomatic group comparing with H. pylori-uninfected group. Sphingomonas may be an indicator between symptomatic and asymptomatic patients with H. pylori infection, the AUC value of Sphingomonas is 0.79. Interactions between species increased and altered notably after H. pylori infection. More genera were affected by Helicobacter in H. pylori-infected asymptomatic patients. The function condition changed significantly in asymptomatic patients with H. pylori infection, there was no difference comparing with symptomatic ones. Amino acid metabolism and lipid metabolism strengthened but carbohydrate metabolism remained constant after H. pylori infection. The metabolism of fatty acid and bile acid was disturbed after infection with H. pylori.

CONCLUSION

The gastric microbiota composition and function mode changed significantly after H. pylori infection regardless of the presence of clinical symptoms, there was no difference between H. pylori-infected asymptomatic and symptomatic patients. The difference in gastric microbiota composition and interactions between species might be responsible for presence of digestive symptoms.

Prognostic effects of the gastric mucosal microbiota in gastric cancer

Gastric cancer (GC) is one of the most common malignant tumors with a high incidence and mortality. Microbiota play a significant role in human health and disease. We aimed to investigate the prognostic value of the gastric microbiota in different stomach microhabitats. We used our previously published 16S rRNA gene sequence data. We retrospectively enrolled a cohort of 132 patients with GC with complete prognostic information and selected 78 normal tissues, 49 peritumoral tissues, and 112 tumoral tissues for microbiota analysis. Patients with different prognoses showed different gastric microbiota compositions and diversity. The association network of the abundant gastric microbiota was more complicated in patients with poor prognoses. In the peritumoral microhabitat of patients with good prognoses, Helicobacter was significantly increased, whereas Halomonas and Shewanella were significantly decreased relative to that in the peritumoral microhabitat of patients with poor prognoses. PiCRUSt analysis revealed that the peritumoral microbiota had more different Kyoto Encyclopedia of Genes and Genomes pathways than did the tumoral and normal microbiota. This study evaluated the long-term prognostic value of the gastric mucosal microbiota in patients with GC. These findings suggested that the characteristic alterations of the gastric mucosal microbiota may be markers for clinical outcomes in these patients.

Global and regional prevalence of Helicobacter pylori in drinking waters: A sustainable, human development and socio-demographic indices based meta-regression-modelling

Helicobacter pylori (Hp) transmission dynamics via drinking water (DW) has a far much higher direct and indirect public health disease burden than previously thought. This study aimed to assess the global prevalence of Hp in DW, distributions across regions and socioeconomic indices (continent, world bank income, Human Development Index (HDI), Sustainable Development Index (SuDI), Socio-Demographic Index (SDI) quintile, and WHO regions). Hp-DW related data mined from five databases until 10/12/2022 according to PRISMA standard were quality-appraised and fitted to a generalized linear mixed-effects model. Sub-group analysis and meta-regression-modelling coupled with a 1000-permutation test (_⁎) were conducted. The global prevalence of Hp in DW was 15.7% (95% confidence interval [CI]: 7.98-27.5), which varied significantly by sampling methods (Moore swabbing (61.0% [0.00-100.0]) vs. grab sampling (13.68%[6.99-25.04])) and detection technique (non-culture (21.35%[9.13-42.31]) vs. cultured-based methods (Psubgroup < 0.01)). The period 1990-99 had the highest prevalence (41.24% [0.02-99.97]). Regarding regional designations, Hp prevalence in DW was significantly different being highest in North America (61.82% [41.03-79.02]) by continents, AMR (42.66% [20.81-67.82]) by WHO group, high HDI (24.64% [10.98-46.43]) by HDI group and North America (61.90% [2.79-98.93]) by world bank region (Psubgroup < 0.01). Generally, sample preparation, SuDI grouping, and detection/confirmation techniques, have significant effects on the detection/prevalence of Hp in DW (Psubgroup < 0.01). Hp prevalence in DW was not significantly different among rural and urban DW (Psubgroup = 0.90), world bank income groups (Psubgroup = 0.15), and SDI quintiles (Psubgroup = 0.07). Among the predictors examined, only sample size (p < 0.1, R_∗²(coefficient of determinant) = 15.29%), continent (p_∗val = 0.04), HDI (p_∗val = 0.02), HDI group (p_∗val = 0.05), and microbiological methods (p < 0.1; R_∗²=28.09 %) predicted Hp prevalence in DW robustly. In conclusion, Hp prevalence is still endemic in DW regardless of the regional designations/improve DW supplies.

Evaluation of polygenic risk score for risk prediction of gastric cancer

Genetic variations are associated with individual susceptibility to gastric cancer. Recently, polygenic risk score (PRS) models have been established based on genetic variants to predict the risk of gastric cancer. To assess the accuracy of current PRS models in the risk prediction, a systematic review was conducted. A total of eight eligible studies consisted of 544842 participants were included for evaluation of the performance of PRS models. The overall accuracy was moderate with Area under the curve values ranging from 0.5600 to 0.7823. Incorporation of epidemiological factors or Helicobacter pylori (H. pylori) status increased the accuracy for risk prediction, while selection of single nucleotide polymorphism (SNP) and number of SNPs appeared to have little impact on the model performance. To further improve the accuracy of PRS models for risk prediction of gastric cancer, we summarized the association between gastric cancer risk and H. pylori genomic variations, cancer associated bacteria members in the gastric microbiome, discussed the potentials for performance improvement of PRS models with these microbial factors. Future studies on comprehensive PRS models established with human SNPs, epidemiological factors and microbial factors are indicated.

Regulatory effect of moderate Jiang-flavour baijiu (Chinese liquor) dosage on organ function and gut microbiota in mice

Chinese baijiu, an ancient fermented alcoholic beverage, contains ethanol and a variety of compounds. One of the most popular types of Chinese baijiu is Jiang-flavor baijiu. To investigate the effects of Jiang-flavor baijiu on organ function and gut microbiota, we developed a moderate drinking mouse model and studied its effects on the liver, kidney biomarkers, memory function, and gut microbiota. The results showed that ethanol caused more hepatic steatosis, liver and kidney damage, and memory impairment than Jiang-flavour baijiu consumption. Furthermore, Jiang-flavor baijiu altered the gut microbiota by increasing the abundance of beneficial taxa such as Lactobacillus and Akkermansia, whereas ethanol increased the abundance of harmful bacteria such as Prevotella and Mucispirillum. Our findings provide preliminary evidence that moderate dose Jiang-flavor baijiu regulates gut microbiota and organ function and provide a theoretical foundation for future research on the positive health effects of particular varieties of Chinese baijiu.

Gastric microbiota in gastric cancer: Different roles of Helicobacter pylori and other microbes

Gastric cancer (GC) is one of the leading causes of cancer-related deaths worldwide. The gastric microbiota plays a critical role in the development of GC. First, Helicobacter pylori (H. pylori) infection is considered a major risk factor for GC. However, recent studies based on microbiota sequencing technology have found that non-H. pylori microbes also exert effects on gastric carcinogenesis. Following the infection of H. pylori, gastric microbiota dysbiosis could be observed; the stomach is dominated by H. pylori and the abundances of non-H. pylori microbes reduce substantially. Additionally, decreased microbial diversity, alterations in the microbial community structure, negative interactions between H. pylori and other microbes, etc. occur, as well. With the progression of gastric lesions, the number of H. pylori decreases and the number of non-H. pylori microbes increases correspondingly. Notably, H. pylori and non-H. pylori microbes show different roles in different stages of gastric carcinogenesis. In the present mini-review, we provide an overview of the recent findings regarding the role of the gastric microbiota, including the H. pylori and non-H. pylori microbes, in the development of GC.

Dual therapy for Helicobacter pylori infection

ABSTRACT

Bismuth-containing quadruple therapy (BQT) has long been recommended for Helicobacter pylori ( H. pylori ) eradication in China. Meanwhile, in the latest national consensus in China, dual therapy (DT) comprising an acid suppressor and amoxicillin has also been recommended. In recent years, the eradication rate of H. pylori has reached >90% using DT, which has been used not only as a first-line treatment but also as a rescue treatment. Compared with BQT, DT has great potential for H. pylori eradication; however, it has some limitations. This review summarizes the development of DT and its application in H. pylori eradication. The H. pylori eradication rates of DT were comparable to or even higher than those of BQT or standard triple therapy, especially in the first-line treatment. The incidence of adverse events associated with DT was lower than that with other therapies. Furthermore, there were no significant differences in the effects of dual and quadruple therapies on gastrointestinal microecology. In the short term, H. pylori eradication causes certain fluctuations in the gastrointestinal microbiota; however, in the long term, the gastrointestinal microbiota eventually returns to its normal state. In the penicillin-naïve population, patients receiving DT have a high eradiation rate, better compliance, lower incidence of adverse reactions, and lower primary and secondary resistance to amoxicillin. These findings suggest the safety, efficacy, and potential of DT for H. pylori eradication.

Clinical Pathogenesis, Molecular Mechanisms of Gastric Cancer Development

The human pathogen Helicobacter pylori is the strongest known risk factor for gastric disease and cancer, and gastric cancer remains a leading cause of cancer-related death across the globe. Carcinogenic mechanisms associated with H. pylori are multifactorial and are driven by bacterial virulence constituents, host immune responses, environmental factors such as iron and salt, and the microbiota. Infection with strains that harbor the cytotoxin-associated genes (cag) pathogenicity island, which encodes a type IV secretion system (T4SS) confer increased risk for developing more severe gastric diseases. Other important H. pylori virulence factors that augment disease progression include vacuolating cytotoxin A (VacA), specifically type s1m1 vacA alleles, serine protease HtrA, and the outer-membrane adhesins HopQ, BabA, SabA and OipA. Additional risk factors for gastric cancer include dietary factors such as diets that are high in salt or low in iron, H. pylori-induced perturbations of the gastric microbiome, host genetic polymorphisms, and infection with Epstein-Barr virus. This chapter discusses in detail host factors and how H. pylori virulence factors augment the risk of developing gastric cancer in human patients as well as how the Mongolian gerbil model has been used to define mechanisms of H. pylori-induced inflammation and cancer.

Multidrug resistance in Helicobacter pylori infection

Helicobacter pylori (Hp), a well-known human pathogen, causes one of the most common chronic bacterial infections and plays an important role in the emergence of chronic progressive gastric inflammation and a variety of gastrointestinal diseases. The prevalence of Hp infection varies worldwide and is indirectly proportional to socio-economic status, especially during childhood. The response to the eradication therapy significantly depends on the antibiotic resistance specific to each geographical region; thus, currently, given the increasing prevalence of antimicrobial resistance (especially to clarithromycin, metronidazole, and levofloxacin), successful treatment for Hp eradication has become a real challenge and a critical issue. The most incriminated factors associated with multidrug resistance (MDR) in Hp proved to be the overuse or the improper use of antibiotics, poor medication adherence, and bacterial-related factors including efflux pumps, mutations, and biofilms. Up to 30% of first-line therapy fails due to poor patient compliance, high gastric acidity, or high bacteremia levels. Hence, it is of great importance to consider new eradication regimens such as vonoprazan-containing triple therapies, quintuple therapies, high-dose dual therapies, and standard triple therapies with probiotics, requiring further studies and thorough assessment. Strain susceptibility testing is also necessary for an optimal approach.

Gastric microbiota dysbiosis and Helicobacter pylori infection

Helicobacter pylori (H. pylori) infection is one of the most common causes of gastric disease. The persistent increase in antibiotic resistance worldwide has made H. pylori eradication challenging for clinicians. The stomach is unsterile and characterized by a unique niche. Communication among microorganisms in the stomach results in diverse microbial fitness, population dynamics, and functional capacities, which may be positive, negative, or neutral. Here, we review gastric microecology, its imbalance, and gastric diseases. Moreover, we summarize the relationship between H. pylori and gastric microecology, including non-H. pylori bacteria, fungi, and viruses and the possibility of facilitating H. pylori eradication by gastric microecology modulation, including probiotics, prebiotics, postbiotics, synbiotics, and microbiota transplantation.

Management of Helicobacter pylori infection

Helicobacter pylori infection exhibits a wide disease spectrum ranging from asymptomatic gastritis, peptic ulcer disease, to gastric cancer. H. pylori can induce dysbiosis of gastric microbiota in the pathway of carcinogenesis and successful eradication can restore gastric homeostasis. Diagnostic testing and treatment for H. pylori infection is recommended in patients with active or past history of peptic ulcer, chronic dyspepsia, chronic non-steroidal anti-inflammatory drugs (NSAID) or aspirin use, precancerous gastric lesions, gastric cancer, mucosa-associated lymphoid tissue (MALT) lymphoma, family history of gastric cancer, family history of peptic ulcers, household family member having active H. pylori infection, iron deficiency anemia, idiopathic thrombocytopenic purpura, or vitamin B12 deficiency. Recommended first-line regimens for H. pylori eradication are classified according to clarithromycin resistance. In areas of high clarithromycin resistance (≥15%), we recommend 14-day concomitant therapy or 14-day bismuth quadruple therapy (BQT) as first-line regimen. In areas of low clarithromycin resistance (<15%), we recommend 14-day triple therapy or 14-day BQT as first-line treatment. Second-line regimens are 14-day levofloxacin triple therapy or 14-day BQT if BQT is not previously used. For patients with multiple treatment failure, antimicrobial susceptibility testing (AST) should be performed. If AST is not available, we recommend using antibiotics not previously used or for which resistance is unlikely, such as amoxicillin, tetracycline, bismuth, or furazolidone. High-dose potent proton pump inhibitor or vonoprazan is recommended to achieve adequate acid suppression. Probiotics can be used as an adjuvant treatment to reduce the side effects of antibiotics and enhance eradication rate.

The Gut Microbiome and Its Implication in the Mucosal Digestive Disorders

The gastrointestinal (GI) tract is one of the most studied compartments of the human body as it hosts the largest microbial community including trillions of germs. The relationship between the human and its associated flora is complex, as the microbiome plays an important role in nutrition, metabolism and immune function. With a dynamic composition, influenced by many intrinsic and extrinsic factors, there is an equilibrium maintained in the composition of GI microbiota, translated as "eubiosis". Any disruption of the microbiota leads to the development of different local and systemic diseases. This article reviews the human GI microbiome's composition and function in healthy individuals as well as its involvement in the pathogenesis of different digestive disorders. It also highlights the possibility to consider flora manipulation a therapeutic option when treating GI diseases.

Development of plasma ghrelin level as a novel marker for gastric mucosal atrophy after Helicobacter pylori eradication

BACKGROUND AND AIM

The severity of atrophic gastritis is significantly associated with the risk of gastric cancer. Although the current gold standard for assessing the gastric cancer risk is esophagogastroduodenoscopy with a pathological examination, the development of less-invasive biomarkers is warranted for efficient risk stratification of gastric cancer. Serum pepsinogens (PGs) are biomarkers used to predict the extent of gastric mucosal atrophy; however, they are not an accurate reflection of gastric mucosal atrophy after Helicobacter pylori eradication. The present study was conducted to investigate the usefulness of plasma ghrelin levels as a marker for gastric mucosal atrophy, and as a risk stratification marker for gastric cancer, even after H. pylori eradication.

METHODS

Patients who received H. pylori eradication treatment were enrolled in the study. The severity of gastric mucosal atrophy was evaluated both endoscopically and histologically. Serum pepsinogen and plasma ghrelin levels were measured before and at 1, 12, 24, and 48 weeks after treatment. The study was approved by the Research Ethics Committee of the Keio University School of Medicine (no. 20140102; 8 July 2014).

RESULTS

Eighteen patients completed the study protocol. Total and acyl plasma ghrelin levels demonstrated no significant change from before treatment to 48 weeks after eradication; however, there was a significant difference between open-type and closed-type atrophic gastritis. The PG I/II ratio increased significantly from 48 weeks after H. pylori eradication. The severity of the histological intestinal metaplasia scores correlated inversely with plasma total ghrelin levels from before to 48 weeks after H. pylori eradication.

CONCLUSION

Plasma levels of ghrelin correlate well with the level of gastric mucosal atrophy, even after H. pylori eradication.KEY MESSAGESGhrelin plasma levels are associated with the progression of endoscopic atrophic gastritis, even at 48 weeks after H. pylori eradication.Ghrelin plasma levels are also associated with increased severity of histological intestinal metaplasia 48 weeks after H. pylori eradication.Pepsinogen I/II ratios increased immediately after H. pylori eradication and are inappropriate for assessing atrophic gastritis after H. pylori eradication.

The Effect of Quadruple Therapy with Polaprezinc or Bismuth on Gut Microbiota after Helicobacter pylori Eradication: A Randomized Controlled Trial

Background: Quadruple therapy with polaprezinc provided an alternative to Helicobacter pylori eradication; however, the effect on gut microbiota remains uncertain. This study aims to identify whether polaprezinc-containing quadruple therapy causes adverse microbiota effects among asymptomatic adults, compared with bismuth therapy. Methods: This was a randomized control trial. One hundred asymptomatic H. pylori-infected adults were randomly (1:1) assigned to two treatment groups (polaprezinc-containing therapy, PQT; or bismuth-containing therapy, BQT). Fecal samples were collected from subjects before and 4−8 weeks after therapy. Samples were sequenced for the V4 regions of the 16S rRNA gene. Results: The relative abundance of the three dominant bacterial phyla (Bacteroidota, Firmicutes, and Proteobacteria) accounted for more than 95% of each treatment group. The alpha diversity between eradications that succeeded and those that failed had no significant difference (p > 0.05). After successful eradication, the alpha diversity in the BQT group decreased in comparison with the baseline (p < 0.05). Subjects who were successfully eradicated by BQT showed considerably lower alpha diversity indices than those of the PQT at follow-up (p < 0.05). The abundance of Parasutterella in subjects who were successfully eradicated by PQT was four times greater than that of BQT (q < 0.05). Conclusion: A 14-day PQT may be superior to BQT in maintaining short-term gut microbiota homeostasis after H. pylori treatment. Our findings preliminarily provide evidence of the short-term impacts of the gut microbiota after PQT treatment of H. pylori infection.

Current and future perspectives for Helicobacter pylori treatment and management: From antibiotics to probiotics

Helicobacter pylori (H. pylori) is a Gram-negative anaerobic bacterium that colonizes the human stomach and is the leading cause of gastric diseases such as chronic gastritis and peptic ulcers, as well as the most definite and controllable risk factor for the development of gastric cancer. Currently, the regimen for H. pylori eradication has changed from triple to quadruple, the course of treatment has been extended, and the type and dose of antibiotics have been adjusted, with limited improvement in efficacy but gradually increasing side effects and repeated treatment failures in an increasing number of patients. In recent years, probiotics have become one of the most important tools for supporting intestinal health and immunity. Numerous in vitro studies, animal studies, and clinical observations have demonstrated that probiotics have the advantage of reducing side effects and increasing eradication rates in adjuvant anti-H. pylori therapy and are a valuable supplement to conventional therapy. However, many different types of probiotics are used as adjuncts against H. pylori, in various combinations, with different doses and timing, and the quality of clinical studies varies, making it difficult to standardize the results. In this paper, we focus on the risk, status, prevention, control, and treatment of H. pylori infection and review international consensus guidelines. We also summarize the available scientific evidence on using Limosilactobacillus reuteri (L. reuteri) as a critical probiotic for H. pylori treatment and discuss its clinical research and application from an evidence-based perspective.

Probiotics modulate gastrointestinal microbiota after Helicobacter pylori eradication: A multicenter randomized double-blind placebo-controlled trial

BACKGROUND

Helicobacter pylori (H. pylori) eradication has been reported to cause short-term disruption of gut microbiota. It is acknowledged that probiotics supplementation mitigates side effects induced by H. pylori eradication, yet its role on alleviating dysbiosis of microbiota is obscure.

OBJECTIVES

To evaluate the impact of probiotics on gastrointestinal microbiota after eradication therapy.

METHODS

This was a multicenter, double-blinded, randomized trial done at seven centers in China. A total of 276 treatment-naïve H. pylori-positive patients were randomly assigned to receive 14-day bismuth-containing quadruple therapy (esomeprazole, bismuth, amoxicillin, furazolidone) combined with probiotics (Bifidobacterium Tetragenous viable Bacteria Tablets) (n=140) or placebo (n=136) for 28 days. Saliva, gastric mucosa and fecal samples were collected before and after therapy for 16S rRNA gene sequencing.

RESULTS

The incidence of gastrointestinal adverse events was lower in probiotics group compared to placebo group (23.6% vs 37.7%, p=0.016), while there was no significant difference in eradication rate. We found dramatic perturbations of gut microbiota immediately following eradication, with the predominance of Proteobacteria in replacement of commensal Firmicutes and Bacteroidetes, and gradually restored after two weeks. The reduction of gut Bacteroidetes caused by eradication drugs was neutralized with probiotics supplementation. The gastric microbiota was completely reconstituted with H. pylori depleted and other taxa flourished. Of note, patients treated with probiotics showed smaller fluctuations of gastric microbiota compared to those with placebo. We also observed changes of saliva microbiota after H. pylori eradication, illustrated by the overgrowth of Neisseria and depletion of Streptococcus. The expansion of some pathogenic genera, including Porphyromonas, Leptotrichia, in the mouth was suppressed by probiotics.

CONCLUSION

This study not only demonstrated the beneficial effect of probiotics implementation on side events during H. pylori eradication but also provided a comprehensive profile of microbiome alterations along gastrointestinal tract that modulated by probiotics.