Vonoprazan-amoxicillin dual therapy for Helicobacter pylori eradication in Chinese population: A prospective, multicenter, randomized, two-stage study.

BACKGROUND: The efficacy of Vonoprazan-amoxicillin dual therapy (VAT) in the treatment of Helicobacter pylori (H. pylori) is controversial. AIM: To evaluate the efficacy of VAT in the Chinese population. METHODS: This prospective, multicenter, randomized, open-label, and two-stage study was conducted at 23 centers in Fujian, China (May 2021-April 2022). H. pylori-infected patients were randomized to bismuth quadruple therapy (BQT), BQT-Vonoprazan (BQT-V), seven-day VAT (VAT-7), ten-day VAT (VAT-10), and fourteen-day VAT (VAT-14) groups. The primary endpoint was the H. pylori eradication rate. The secondary endpoint was the frequency of adverse events. This study was registered with the Chinese Clinical Trial Registry, ChiCTR2100045778. RESULTS: In the first stage, VAT-7 and BQT-V groups were selected for early termination because less than 23 among 28 cases were eradicated. In the second stage, the eradication rates for BQT, VAT-10, and VA-14 were 80.2% [95% confidence interval (95%CI): 71.4%-86.8%], 93.2% (86.6%-96.7%), 92.2% (85.3%-96.0%) in the intention-to-treat (ITT) analysis, and 80.9% (95%CI: 71.7%-87.5%), 94.0% (87.5%-97.2%), and 93.9% (87.4%-97.2%) in the per-protocol analysis. The ITT analysis showed a higher eradication rate in the VAT-10 and VAT-14 groups than in the BQT group (P = 0.022 and P = 0.046, respectively). The incidence of adverse events in the VAT-10 and VAT-14 groups was lower than in the BQT group (25.27% and 13.73% vs 37.62%, respectively; P < 0.001). CONCLUSION: VAT with a duration of 10 or 14 days achieves a higher eradication rate than the BQT, with a more tolerable safety profile in H. pylori-infected patients in Fujian.

HELICOBACTER PYLORI AND GALLBLADDER PATHOLOGIES: IS THERE A CAUSE-AND-EFFECT RELATIONSHIP?

The relationship between Helicobacter pylori infection and gallbladder diseases, particularly cholecystitis and gallbladder polyps, remains unclear. This study aimed to investigate the presence of H. pylori in gallbladder tissues and its potential role in gallbladder pathologies, as well as to examine the expression of chemokines CXCL2 and CXCL5 in these conditions. MATERIAL AND METHODS: A total of 137 laparoscopically excised gallbladders were analysed through histological examination, PCR for H. pylori-specific DNA, and quantitative real-time PCR for CXCL2 and CXCL5 gene expression. The study cohort included patients with acute calculous cholecystitis, chronic calculous cholecystitis, and gallbladder polyps. RESULTS: H. pylori was detected in 30.7% of cases by histological methods and 42.3% by PCR. Elevated expression of CXCL2 and CXCL5 was observed in 62% and 57.7% of cases, respectively, with a higher prevalence in acute cholecystitis compared to chronic conditions. However, no statistically significant association was found between H. pylori presence and the forms of cholecystitis, as well as between H. pylori presence and chemokine expression in gallbladder. CONCLUSIONS: The study did not establish a direct link between the presence of H. pylori infection and forms of gallbladder pathologies. The findings suggest that other factors other than H. pylori may contribute to the upregulation of CXCL2 and CXCL5 in gallbladder diseases. Further research is needed to elucidate the complex interactions between H. pylori, chemokines, and gallbladder pathologies.

Analyses of the association between Helicobacter pylori antibody titre and pathogenicity before and after eradication: results of the Kyushu and Okinawa population study, a retrospective observational cohort study.

OBJECTIVES: To assess the utility of Helicobacter pylori antibody testing, we evaluated the correlation between the H. pylori antibody titre and H. pylori-associated pathogenicity and the changes in antibody titre after H. pylori eradication therapy. DESIGN: A retrospective observational cohort study. SETTING AND PARTICIPANTS: From 2004 to 2016, medical check-ups were performed in different regions of Japan. In total, 324 subjects infected with H. pylori who received H. pylori eradication therapy were enrolled; H. pylori was eradicated in 266 of these subjects. We examined the associations between H. pylori antibody titre with pepsinogen and the presence or absence of H. pylori-associated pathogenic proteins, such as cytotoxin-associated gene A and vacuolating cytotoxin gene A, at baseline and after H. pylori eradication therapy. RESULTS: The H.pylori antibody titre showed a positive correlation with pepsinogen II and a negative correlation with the pepsinogen I/II ratio. Moreover, the H.pylori antibody titre significantly correlated with the positive rates of H. pylori-associated pathogenic protein before eradication therapy. Antibody titres decreased after eradication, the pepsinogen I/II ratio increased and the H. pylori-associated pathogenic protein-positive rate decreased in patients with successful eradication. The determination of eradication using the decline in antibody titre 6 months after eradication therapy was useful (area under the receiver operating characteristic curve: 0.98). CONCLUSIONS: Our data indicate that the H. pylori antibody titre may represent the degree of pathogenicity. The H. pylori antibody titre was associated with attenuation of pathogenicity in patients with H. pylori eradication, indicating the clinical utility of H. pylori antibody testing.

Causal association between Helicobacter pylori infection and Sjogren's syndrome: a bidirectional Mendelian randomization analysis.

BACKGROUND: The results of observational studies indicate a potential link between Helicobacter pylori infection and Sjogren's syndrome (SS), but the causal relationship between them remains unknown. This study applied Mendelian randomization (MR) to evaluate this relationship. METHOD: Genome-wide association study (GWAS) summary statistics on H. pylori infection [sample size=8735 (EBI, https://gwas.mrcieu.ac.uk/ )] and SS [sample size=368,028 (cases=2495, controls=365533) (FinnGen, https://r9.finngen.fi/ )] were analyzed. We used bidirectional MR to evaluate the association between H. pylori infection and SS and identify causation. The major MR analysis method was inverse-variance weighted (IVW) MR, supplemented by MR‒Egger and weighted median approaches. In addition, the stability and reliability of the results were tested using the retention method, heterogeneity test, and horizontal gene pleiotropy test. RESULTS: Evidence of the impact of H. pylori infection on SS risk was found in the IVW results [odds ratio (OR)=1.6705; 95% confidence interval (CI)=1.0966 to 2.5446; P=0.0168]. Evidence of the impact of SS on H. pylori infection risk was also found (OR=1.0158; 95% CI=1.0033 to 1.0285; P=0.0128). CONCLUSION: The results of MR analysis support a causal association between H. pylori infection and SS and indicate that SS can lead to a greater risk of H. pylori infection. Our research will support the development of novel approaches for continued H. pylori and SS-related research and therapy that consider the genetic relationship between H. pylori infection and SS.

Correlation of FUT3 and FUT6 Gene Polymorphisms With Helicobacter pylori Infection.

BACKGROUND: Helicobacter pylori infection is a significant pathogen in gastrointestinal diseases. Previous studies have identified single-nucleotide polymorphisms (SNPs) are factors associated with H. pylori infection. Notably, Leb and Sialyl-Lex antigens, regulated by the FUT3 and FUT6 genes, play a crucial role in H. pylori infection. This study aimed to investigate the correlation between FUT3 and FUT6 gene polymorphisms and H. pylori infection in the Han population of northern China. MATERIALS AND METHODS: An immunoturbidimetric assay was employed to detect H. pylori infection, categorizing subjects into infected and noninfected groups. Gene variants were identified through sequencing. Finally, FUT3 and FUT6 gene polymorphisms were analyzed to assess their association with H. pylori infection. RESULTS: The frequency of the T allele (rs778805) and the G allele (rs61147939) in the infection group was significantly higher than that in the noninfection group (63.4% vs. 55.1%, p = 0.045; 55.2% vs. 47.0%, p = 0.042, respectively). In the infection group, the frequency of the AA genotype (rs3745635) in the recessive model, the TT genotype (rs778805) in the recessive model, and the GG genotype (rs61147939) in the recessive model were significantly higher than the noninfection group (5.8% vs. 2.3%, p = 0.042; 41.9% vs. 29.3%, p = 0.022; 34.9% vs. 20.5%, p = 0.0068, respectively). The frequency of the A13 haplotype and the A13/A13 diplotype of the FUT6 gene was significantly higher in the infection group than in the noninfection group (55.56% vs. 46.32%, p = 0.019; 34.94% vs. 20.30%, p = 0.045, respectively). The rs778805-rs17855739-rs28362459-rs3745635 combination was identified as the best interaction model (p < 0.05). CONCLUSIONS: This study suggests that FUT3 and FUT6 gene polymorphisms are significantly associated with H. pylori infection in the Han Chinese from northern China.

Animal Models of Helicobacter pylori Infection and Vaccines: Current Status and Future Prospects.

Helicobacter pylori infection causes chronic gastritis, ulcers, and gastric cancer, making it a threat to human health. Despite the use of antibiotic therapy, the global prevalence of H. pylori infection remains high, necessitating early eradication measures. Immunotherapy, especially vaccine development, is a promising solution in this direction, albeit the selection of an appropriate animal model is critical in efficient vaccine production. Accordingly, we conducted a literature, search and summarized the commonly used H. pylori strains, H. pylori infection-related animal models, and models for evaluating H. pylori vaccines. Based on factors such as the ability to replicate human diseases, strain compatibility, vaccine types, and eliciting of immune responses, we systematically compared the advantages and disadvantages of different animal models, to obtain the informed recommendations. In addition, we have proposed novel perspectives on H. pylori-related animal models to advance research and vaccine evaluation for the prevention and treatment of diseases such as gastric cancer.

An Economic Evaluation of Family-Based Versus Traditional Helicobacter pylori Screen-and-Treat Strategy: Based on Real-World Data and Microsimulation Model.

OBJECTIVE: There is an economic evaluation on the family-based Helicobacter pylori screen-and-treat strategy (FBHS) in China. This study aimed to compare the cost-effectiveness of the FBHS with the traditional H. pylori screen-and-treat strategy (TBHS). MATERIALS AND METHODS: A seven-state microsimulation model, including H. pylori infection and gastric cancer states, was constructed on the basis of the target family samples from 29 provinces in China. Taking a lifetime horizon from a healthcare system perspective, the long-term costs and health outcomes of the FBHS and TBHS screening strategies were simulated separately, and economic evaluations were performed. The model parameters were primarily derived from real-world data, published literature, and expert opinions. The primary outcome was the incremental cost-effectiveness ratio (ICER) expressed as cost/quality-adjusted life-year (QALY) gained. One-way sensitivity analysis, probabilistic sensitivity analysis, and scenario analysis were performed to assess the uncertainty of the results. RESULTS: The base-case analysis revealed that the average costs for FBHS and TBHS were 563.67 CNY and 574.08 CNY, respectively, with corresponding average QALYs of 14.83 and 14.79. The ICER for the comparison between the two strategies was -214.07, indicating that FBHS was an absolutely dominant strategy with better cost-effectiveness. The results of both one-way sensitivity analysis and probabilistic sensitivity analysis were robust. When taking into account the added benefit of the higher H. pylori eradication rate in FBHS, the average costs were further reduced, and the average QALYs were increased, solidifying its position as an unequivocally dominant strategy. CONCLUSION: The FBHS is an absolutely dominant and cost-effective strategy that enables an optimized allocation of screening resources. Decision-makers should prioritize FBHS when developing H. pylori prevention and control strategies.

Validity of rapid urease test using swab of gastric mucus to mucosal forceps and 13 C-urease breath test: a multicenter prospective observational study.

BACKGROUND: Theoretically, a rapid urease test (RUT) using a swab of the gastric wall (Swab-RUT) for Helicobacter pylori (H. pylori) is safe. However, the validity and utility of Swab-RUT remain unclear. Therefore, we assessed the validity and utility of Swab-RUT compared to RUT using mucosal forceps of the gastric wall (Forceps-RUT) and 13C-urea breath test (UBT). METHODS: This study was a multicenter prospective observational study. When the examinees were suspected of H. pylori infection during esophagogastroduodenoscopy, we performed Swab-RUT and Forceps-RUT continuously. When the examinees were not suspected of H. pylori infection, we performed Swab-RUT alone. We validated the status of H. pylori infection using UBT. RESULTS: Ninety-four examinees were enrolled from four institutions between May 2016 and December 2020 (median age [range], 56.5 [26-88] years). In this study, the sensitivity, specificity, and accuracy of Swab-RUT to UBT were 0.933 (95% confidence interval: 0.779-0.992), 0.922 (0.827-0.974), and 0.926 (0.853-0.970), respectively. The Kappa coefficient of Swab-RUT to UBT was 0.833, and that of Swab-RUT to forceps-RUT was 0.936. No complications were observed in this study. CONCLUSIONS: Swab-RUT is a valid examination for the status of H. pylori infection compared to the conventional Forceps-RUT.

Prevalence of Helicobacter pylori infection among patients with esophageal carcinoma.

BACKGROUND: Helicobacter pylori (H. pylori) is a widespread microorganism related to gastric adenocarcinoma (AC). In contrast, it has been reported that an inverse association exists between H. pylori infection and esophageal carcinoma. The mechanisms underlying this supposedly protective effect remain controversial. AIM: To determine the prevalence of H. pylori infection in esophageal carcinoma patients, we performed a retrospective observational study of esophageal tumors diagnosed in our hospital. METHODS: We retrospectively reviewed the prevalence of H. pylori infection in a cohort of patients diagnosed with esophageal carcinoma. Concomitant or previous proton pump inhibitor (PPI) usage was also recorded. RESULTS: A total of 89 patients with esophageal carcinoma (69 males, 77.5%), with a mean age of 66 years (range, 26-93 years) were included. AC was the most frequent pathological variant (n = 47, 52.8%), followed by squamous cell carcinoma (n = 37, 41.6%). Fourteen ACs (29.8%) originated in the gastroesophageal junction and 33 (70.2%) in the esophageal body. Overall, 54 patients (60.7%) presented at stages III and IV. Previous H. pylori infection occurred only in 4 patients (4.5%), 3 with AC (6.3% of all ACs) and 1 with squamous cell carcinoma (2.7% of all squamous cell tumors). All patients with previous H. pylori infection had stage III-IV. Only one patient had received prior H. pylori eradication therapy, whereas 86 (96.6%) had received previous or concomitant PPI treatment. CONCLUSION: In our cohort of patients, and after histologic evaluation of paraffin-embedded primary tumors, we found a very low prevalence of previous H. pylori infection. We also reviewed the medical history of the patients, concluding that the majority had received or were on PPI treatment. The minimal prevalence of H. pylori infection found in this cohort of patients with esophageal carcinoma suggests a protective role.

Empirical Therapy Versus Tailored Therapy of Helicobacter pylori in Korea: Results of the K-CREATE Study.

BACKGROUND: The optimal duration of regimens for tailored therapy based on genotypic resistance for clarithromycin has yet to be established. AIM: This study was a nationwide, multicenter, randomized trial comparing empirical therapy with tailored therapy based on genotypic resistance for first-line eradication of Helicobacter pylori. We also compared the eradication rates of 7- and 14-day regimens for each group. PATIENTS AND METHODS: Patients with H. pylori infection were first randomized to receive empirical or tailored therapy. Patients in each group were further randomized into 7- or 14-day regimens. Empirical therapy consisted of a triple therapy (TT) regimen (twice-daily doses of pantoprazole 40 mg, amoxicillin 1 g, and clarithromycin 500 mg) for 7 or 14 days. Tailored therapy consisted of TT of 7 or 14 days in patients without genotypic resistance. Patients with genotypic resistance were treated with bismuth quadruple therapy (BQT) regimens (twice-daily doses of pantoprazole 40 mg, three daily doses of metronidazole 500 mg, and four times daily doses of bismuth 300 mg and tetracycline 500 mg) for 7 or 14 days. A 13C-urea breath test assessed eradication rates. The primary outcome was eradication rates of each group. RESULTS: A total of 593 patients were included in the study. The eradication rates were 65.7% (201/306) in the empirical therapy group and 81.9% (235/287) in the tailored therapy group for intention-to-treat analysis (p < 0.001). In the per-protocol analysis, the eradication rates of the empirical therapy and tailored groups were 70.3% (201/286) and 85.5% (235/274) (p < 0.001), respectively. There was no difference in compliance between the two groups. The rate of adverse events was higher in the tailored group compared to the empirical group (p < 0.001). DISCUSSION: Our study confirmed that tailored therapy based on genotypic resistance was more effective than empirical therapy for H. pylori eradication in Korea. However, no significant difference was found between 7- and 14-day regimens for each group. Future studies are needed to determine the optimal duration of therapy for empirical and tailored therapy regimens.

Progranulin inhibits autophagy to facilitate intracellular colonization of Helicobacter pylori through the PGRN/mTOR/DCN axis in gastric epithelial cells.

Helicobacter pylori (H. pylori) infection is the primary risk factor for the progress of gastric diseases. The persistent stomach colonization of H. pylori is closely associated with the development of gastritis and malignancies. Although the involvement of progranulin (PGRN) in various cancer types has been well-documented, its functional role and underlying mechanisms in gastric cancer (GC) associated with H. pylori infection remain largely unknown. This report demonstrated that PGRN was up-regulated in GC and associated with poor prognosis, as determined through local and public database analysis. Additionally, H. pylori induced the up-regulation of PGRN in gastric epithelial cells both in vitro and in vivo. Functional studies have shown that PGRN promoted the intracellular colonization of H. pylori. Mechanistically, H. pylori infection induced autophagy, while PGRN inhibited autophagy to promote the intracellular colonization of H. pylori. Furthermore, PGRN suppressed H. pylori-induced autophagy by down-regulating decorin (DCN) through the mTOR pathway. In general, PGRN inhibited autophagy to facilitate intracellular colonization of H. pylori via the PGRN/mTOR/DCN axis. This study provides new insights into the molecular mechanisms underlying the progression of gastric diseases, suggesting PGRN as a potential therapeutic target and prognostic predictor for these disorders.

Gamma-glutamyl transferase secreted by Helicobacter pylori promotes the development of gastric cancer by affecting the energy metabolism and histone methylation status of gastric epithelial cells.

BACKGROUND: Helicobacter pylori (H. pylori) infection is critical in the development and occurrence of gastric cancer. H. pylori secretes gamma-glutamyl transferase (GGT), which affects energy metabolism and histone methylation in mesenchymal stem cells. However, its effect on human gastric epithelial cells remains unclear. This study aimed to investigate the effects of GGT on energy metabolism and histone methylation in gastric epithelial cells and determine its role in the development and progression of H. pylori-induced gastric cancer. METHODS: A GGT knockout H. pylori strain and mouse gastric cancer model were constructed, and alpha-ketoglutarate (α-KG) was added. The underlying mechanism was investigated using proteomics, immunohistochemistry, Western blotting, and other experimental assays. RESULTS: H. pylori can colonize the host's stomach and destroy the gastric epithelium. GGT secreted by H. pylori decreased the concentration of glutamine in the stomach and increased H3K9me3 and H3K27me3 expression, which promoted the proliferation and migration of gastric epithelial cells. Additionally, α-KG reversed this effect. GGT increased the tumorigenic ability of nude mice. GGT, secreted by H. pylori, promoted the expression of ribosomal protein L15 (RPL15), while GGT knockout and supplementation with α-KG and trimethylation inhibitors reduced RPL15 expression and Wnt signaling pathway expression. CONCLUSIONS: H. pylori secreted GGT decreased the expression of glutamine and α-KG in gastric epithelial cells, increased the expression of histones H3K9me3 and H3K27me3, and activated the Wnt signaling pathway through RPL15 expression, ultimately changing the biological characteristics of the gastric epithelium and promoting the occurrence of gastric cancer. Altered energy metabolism and histone hypermethylation are important factors involved in this process.

Characteristics of Helicobacter pylori Eradication Therapy in Patients 80 Years or Older Living in a Metropolitan Area: A Multicenter Retrospective Study.

BACKGROUND: The situation of Helicobacter pylori eradication therapy has been changing over time, owing to increases in antimicrobial-resistant strains, lifestyle improvements, and changes in indications for eradication. In Japan, eradication therapy is now available to all H. pylori-positive patients under the medical insurance system, and the potassium-competitive acid blocker vonoprazan has been used for eradication from 2015. Recently, with the aging of society, opportunities to provide eradication to elderly patients are increasing, but the current status and effectiveness of eradication in elderly patients remains unclear. Therefore, we aimed to investigate the trends of H. pylori eradication in a metropolitan area to determine the factors associated with successful H. pylori eradication in elderly patients older than 80 years. METHODS: Trends in the eradication rates of patients who received first- or second-line eradication at 20 hospitals in the Tokyo metropolitan area from 2013 to 2023 were investigated. RESULTS: The eradication rates in the per-protocol analysis were 82.3% (95% confidence interval [CI]: 81.2%-83.2%) for the first-line treatment (n = 6481), and 87.9% (86.9%-88.9%) for the second-line treatment (n = 4899). Multivariate analysis showed that independent factors for successful eradication in the first-line treatment were an age of older than 80 years (OR: 0.606; 95% CI: 0.448-0.822), peptic ulcers (vs. atrophic gastritis: 3.817; 3.286-4.433), and vonoprazan (vs. proton pump inhibiters (PPIs), 3.817; 3.286-4.433), and an age of older than 80 years (0.503; 0.362-0.699) and vonoprazan (1.386; 1.153-1.667) in the second-line treatment. CONCLUSION: After 2015, the eradication rate of both first- and second-line therapies were maintained at a higher level than before 2015, owing to the use of vonoprazan. As the H. pylori eradication rate in patients older than 80 years was low, an effective strategy for these patients needs to be developed in the future.

Exploring the Underlying Mechanisms of Preventive Treatment Related to Dietary Factors for Gastric Diseases.

Gastric diseases have emerged as one of the main chronic diseases in humans, leading to considerable health, social, and economic burdens. As a result, using food or "food and medicinal homologous substances" has become an effective strategy to prevent gastric diseases. Diet may play a crucial role in the prevention and mitigation of gastric diseases, particularly long-term and regular intake of specific dietary components that have a protective effect on the stomach. These key components, extracted from food, include polysaccharides, alkaloids, terpenoids, polyphenols, peptides, probiotics, etc. The related mechanisms involve regulating gastric acid secretion, protecting gastric mucosa, increasing the release of gastric defense factors, decreasing the level of inflammatory factors, inhibiting Helicobacter pylori infection, producing antioxidant effects or reducing oxidative damage, preventing gastric oxidative stress by inhibiting lipid peroxides, activating Nrf2 signaling pathway, and inhibiting NF-κB, TLR4, and NOS/NO signaling pathways.

Eliminating a gut microbe could slash gastric cancers.

Mammoth study in Chinese villages shows antibiotics that kill Helicobacter pylori reduced cancer risk.

Gene content, phage cycle regulation model and prophage inactivation disclosed by prophage genomics in the Helicobacter pylori Genome Project.

Prophages can have major clinical implications through their ability to change pathogenic bacterial traits. There is limited understanding of the prophage role in ecological, evolutionary, adaptive processes and pathogenicity of Helicobacter pylori, a widespread bacterium causally associated with gastric cancer. Inferring the exact prophage genomic location and completeness requires complete genomes. The international Helicobacter pylori Genome Project (HpGP) dataset comprises 1011 H. pylori complete clinical genomes enriched with epigenetic data. We thoroughly evaluated the H. pylori prophage genomic content in the HpGP dataset. We investigated population evolutionary dynamics through phylogenetic and pangenome analyses. Additionally, we identified genome rearrangements and assessed the impact of prophage presence on bacterial gene disruption and methylome. We found that 29.5% (298) of the HpGP genomes contain prophages, of which only 32.2% (96) were complete, minimizing the burden of prophage carriage. The prevalence of H. pylori prophage sequences was variable by geography and ancestry, but not by disease status of the human host. Prophage insertion occasionally results in gene disruption that can change the global bacterial epigenome. Gene function prediction allowed the development of the first model for lysogenic-lytic cycle regulation in H. pylori. We have disclosed new prophage inactivation mechanisms that appear to occur by genome rearrangement, merger with other mobile elements, and pseudogene accumulation. Our analysis provides a comprehensive framework for H. pylori prophage biological and genomics, offering insights into lysogeny regulation and bacterial adaptation to prophages.

CagA toxin and risk of Helicobacter pylori-infected gastric phenotype: A meta-analysis of observational studies.

BACKGROUND: Helicobacter pylori (H. pylori) is frequently associated with non-cardia type gastric cancer, and it is designated as a group I carcinogen. This study aimed to systematically review and meta-analyze the evidence on the prevalence of CagA status in people with gastric disorders in the Indo-Pacific region, and to examine the association of CagA positive in the risk of gastric disorders. This study focused on the Indo-Pacific region owing to the high disability adjusted life-years related to these disorders, the accessibility of efficient treatments for this common bacterial infection, and the varying standard of care for these disorders, particularly among the elderly population in the region. METHODS: Relevant studies were identified in the health-related electronic databases including PubMed, Ovid, Medline, Ovid Embase, Index Medicus, and Google Scholar that were published in English between 1 January 2000, and 18 November 2023. For pooled prevalence, meta-analysis of proportional studies was done, after Freeman-Tukey double arcsine transformation of data. A random-effect model was used to compute the pooled odds ratio (OR) and 95% confidence interval (CI) to investigate the relationship between CagA positivity and gastric disorders. RESULTS: Twenty-four studies from eight Indo-Pacific countries (Bhutan, India, Indonesia, Malaysia, Myanmar, Singapore, Thailand, Vietnam) were included. Overall pooled prevalence of CagA positivity in H. pylori-infected gastric disorders was 83% (95%CI = 73-91%). Following stratification, the pooled prevalence of CagA positivity was 78% (95%CI = 67-90%) in H. pylori-infected gastritis, 86% (95%CI = 73-96%) in peptic ulcer disease, and 83% (95%CI = 51-100%) in gastric cancer. Geographic locations encountered variations in CagA prevalence. There was a greater risk of developing gastric cancer in those with CagA positivity compared with gastritis (OR = 2.53,95%CI = 1.15-5.55). CONCLUSION: Findings suggest that the distribution of CagA in H. pylori-infected gastric disorders varies among different type of gastric disorders in the study countries, and CagA may play a role in the development of gastric cancer. It is important to provide a high standard of care for the management of gastric diseases, particularly in a region where the prevalence of these disorders is high. Better strategies for effective treatment for high-risk groups are required for health programs to revisit this often-neglected infectious disease.

CagA 3' region polymorphism of Helicobacter pylori and its association with chronic gastritis in the Chinese population.

Introduction. Cytotoxin-associated gene A (CagA) from Helicobacter pylori is highly related to chronic gastritis. Tyrosine phosphorylation of Glu-Pro-Ile-Tyr-Ala (EPIYA) motifs from CagA determines the pathogenicity of H. pylori.Gap statement. The precise amino acid variations surrounding the EPIYA motifs and their correlation with clinical outcomes have been poorly explored.Aim. The purpose of this study was to examine the CagA 3' region polymorphism of H. pylori and its association with chronic gastritis in the Chinese population.Method. A total of 86 cagA-positive H. pylori strains were isolated from patients with chronic gastritis in two different hospitals in Beijing, PR China. Genomic DNA was extracted commercial kits, and the cagA 3' variable region of H. pylori was amplified by polymerase chain reaction (PCR). The PCR products were sequenced and analysed using the CLC Sequence Viewer, BioEdit, and WebLogo 3.Results. Two hundred and fifty-nine EPIYA motifs were identified from cagA-positive H. pylori strains. Notably, EPIYA-B exhibited a higher frequency of variation in comparison to EPIYA-A, EPIYA-C, and EPIYA-D. The prevalent sequences for East-Asian-type CagA were QVNK and TIDF, while KVNK and TIDD were most commonly observed for Western-type CagA. The CRPIA motifs of East-Asian-type CagA and Western-type CagA varied at positions 4, 6, 7, 8, and 10. CagA-ABD (73.2%) was the most prevalent type, followed by CagA-ABC (18.6%) and CagA-AB (3.4%). The ratio of CagA-ABD was observed to be higher in cases of chronic non-atrophic gastritis with erosive (NAGE) or chronic atrophic gastritis (AG) compared to chronic non-atrophic gastritis (NAG), and the difference was found to be statistically significant (χ2=59.000/64.000, P<0.001).Conclusions. The EPIYA segments of Western-type CagA and East-Asian-type CagA differ significantly and the presence of CagA-ABD may be associated with severe chronic gastritis from this study.

Candidate Antigens and the Development of Helicobacter pylori Vaccines.

BACKGROUND: Infection with Helicobacter pylori (Hp) mostly occurs during childhood, and persistent infection may lead to severe gastric diseases and even gastric cancer. Currently, the primary method for eradicating Hp is through antibiotic treatment. However, the increasing multidrug resistance in Hp strains has diminished the effectiveness of antibiotic treatments. Vaccination could potentially serve as an effective intervention to resolve this issue. AIMS: Through extensive research and analysis of the vital protein characteristics involved in Hp infection, we aim to provide references for subsequent vaccine antigen selection. Additionally, we summarize the current research and development of Hp vaccines in order to provide assistance for future research. MATERIALS AND METHODS: Utilizing the databases PubMed and the Web of Science, a comprehensive search was conducted to compile articles pertaining to Hp antigens and vaccines. The salient aspects of these articles were then summarized to provide a detailed overview of the current research landscape in this field. RESULTS: Several potential antigens have been identified and introduced through a thorough understanding of the infection process and pathogenic mechanisms of Hp. The conserved and widely distributed candidate antigens in Hp, such as UreB, HpaA, GGT, and NAP, are discussed. Proteins such as CagA and VacA, which have significant virulence effects but relatively poor conservatism, require further evaluation. Emerging antigens like HtrA and dupA have significant research value. In addition, vaccines based on these candidate antigens have been compiled and summarized. CONCLUSIONS: Vaccines are a promising method for preventing and treating Hp. While some Hp vaccines have achieved promising results, mature products are not yet available on the market. Great efforts have been directed toward developing various types of vaccines, underscoring the need for developers to select appropriate antigens and vaccine formulations to improve success rates.