Gastric cancer is a leading cause of cancer-related deaths in China. Affecting more than 40% of the world's population, Helicobacter pylori is a major risk factor for gastric cancer. While previous clinical trials indicated that eradication of H. pylori could reduce gastric cancer risk, this remains to be shown using a population-based approach. We conducted a community-based, cluster-randomized, controlled, superiority intervention trial in Linqu County, China, with individuals who tested positive for H. pylori using a 13C-urea breath test randomly assigned to receiving either (1) a 10-day, quadruple anti-H. pylori treatment (comprising 20 mg of omeprazole, 750 mg of tetracycline, 400 mg of metronidazole and 300 mg of bismuth citrate) or (2) symptom alleviation treatment with a single daily dosage of omeprazole and bismuth citrate. H. pylori-negative individuals did not receive any treatment. We examined the incidence of gastric cancer as the primary outcome. A total of 180,284 eligible participants from 980 villages were enrolled over 11.8 years of follow-up, and a total of 1,035 cases of incident gastric cancer were documented. Individuals receiving anti-H. pylori therapy showed a modest reduction in gastric cancer incidence in intention-to-treat analyses (hazard ratio 0.86, 95% confidence interval 0.74-0.99), with a stronger effect observed for those having successful H. pylori eradication (hazard ratio 0.81, 95% confidence interval 0.69-0.96) than for those who failed treatment. Moderate adverse effects were reported in 1,345 participants during the 10-day treatment. We observed no severe intolerable adverse events during either treatment or follow-up. The findings suggest the potential for H. pylori mass screening and eradication as a public health policy for gastric cancer prevention. Chinese Clinical Trial Registry identifier: ChiCTR-TRC-10000979 .

• MeSH
• antibakteriální látky terapeutické užití   aplikace a dávkování   MeSH
• dospělí MeSH
• Helicobacter pylori * účinky léků   MeSH
• infekce vyvolané Helicobacter pylori * farmakoterapie   epidemiologie   mikrobiologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• metronidazol terapeutické užití   aplikace a dávkování   MeSH
• nádory žaludku * prevence a kontrola   epidemiologie   mikrobiologie   MeSH
• omeprazol * terapeutické užití   aplikace a dávkování   MeSH
• organokovové sloučeniny terapeutické užití   aplikace a dávkování   MeSH
• senioři MeSH
• tetracyklin terapeutické užití   aplikace a dávkování   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• randomizované kontrolované studie MeSH
• Geografické názvy
• Čína epidemiologie   MeSH
• Názvy látek
• antibakteriální látky MeSH
• metronidazol MeSH
• omeprazol * MeSH
• organokovové sloučeniny MeSH
• tetracyklin MeSH

OBJECTIVE: Gastrointestinal microbiota may be involved in Helicobacter pylori-associated gastric cancer development. The aim of this study was to explore the possible microbial mechanisms in gastric carcinogenesis and potential dysbiosis arising from H. pylori infection. DESIGN: Deep sequencing of the microbial 16S ribosomal RNA gene was used to investigate alterations in paired gastric biopsies and stool samples in 58 subjects with successful and 57 subjects with failed anti-H. pylori treatment, relative to 49 H. pylori negative subjects. RESULTS: In H. pylori positive subjects, richness and Shannon indexes increased significantly (both p<0.001) after successful eradication and showed no difference to those of negative subjects (p=0.493 for richness and p=0.420 for Shannon index). Differential taxa analysis identified 18 significantly altered gastric genera after eradication. The combination of these genera into a Microbial Dysbiosis Index revealed that the dysbiotic microbiota in H. pylori positive mucosa was associated with advanced gastric lesions (chronic atrophic gastritis and intestinal metaplasia/dysplasia) and could be reversed by eradication. Strong coexcluding interactions between Helicobacter and Fusobacterium, Neisseria, Prevotella, Veillonella, Rothia were found only in advanced gastric lesion patients, and were absent in normal/superficial gastritis group. Changes in faecal microbiota included increased Bifidobacterium after successful H. pylori eradication and more upregulated drug-resistant functional orthologs after failed treatment. CONCLUSION: H. pylori infection contributes significantly to gastric microbial dysbiosis that may be involved in carcinogenesis. Successful H. pylori eradication potentially restores gastric microbiota to a similar status as found in uninfected individuals, and shows beneficial effects on gut microbiota.

• Klíčová slova
• bacterial interactions, gastric diseases, gastric pre-cancer, helicobacter pylori - treatment,
• MeSH
• antibakteriální látky terapeutické užití   MeSH
• biopsie metody   MeSH
• dysbióza * diagnóza   mikrobiologie   MeSH
• feces mikrobiologie   MeSH
• gastritida atrofická * mikrobiologie   patologie   MeSH
• Helicobacter pylori * izolace a purifikace   patogenita   MeSH
• infekce vyvolané Helicobacter pylori * farmakoterapie   patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• metaplazie mikrobiologie   patologie   MeSH
• mikrobiální interakce MeSH
• nádory žaludku * mikrobiologie   patologie   MeSH
• RNA ribozomální 16S izolace a purifikace   MeSH
• střevní mikroflóra genetika   MeSH
• žaludeční sliznice mikrobiologie   patologie   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antibakteriální látky MeSH
• RNA ribozomální 16S MeSH

The performance of diagnostic tests in intervention trials of Helicobacter pylori (H.pylori) eradication is crucial, since even minor inaccuracies can have major impact. To determine the cut-off point for 13C-urea breath test (13C-UBT) and to assess if it can be further optimized by serologic testing, mathematic modeling, histopathology and serologic validation were applied. A finite mixture model (FMM) was developed in 21,857 subjects, and an independent validation by modified Giemsa staining was conducted in 300 selected subjects. H.pylori status was determined using recomLine H.pylori assay in 2,113 subjects with a borderline 13C-UBT results. The delta over baseline-value (DOB) of 3.8 was an optimal cut-off point by a FMM in modelling dataset, which was further validated as the most appropriate cut-off point by Giemsa staining (sensitivity = 94.53%, specificity = 92.93%). In the borderline population, 1,468 subjects were determined as H.pylori positive by recomLine (69.5%). A significant correlation between the number of positive H.pylori serum responses and DOB value was found (rs = 0.217, P < 0.001). A mathematical approach such as FMM might be an alternative measure in optimizing the cut-off point for 13C-UBT in community-based studies, and a second method to determine H.pylori status for subjects with borderline value of 13C-UBT was necessary and recommended.

• MeSH
• algoritmy * MeSH
• dechové testy metody   MeSH
• diagnostické techniky molekulární normy   MeSH
• dospělí MeSH
• infekce vyvolané Helicobacter pylori diagnóza   MeSH
• izotopy uhlíku MeSH
• klinické zkoušky jako téma MeSH
• lidé středního věku MeSH
• lidé MeSH
• limita detekce MeSH
• močovina MeSH
• nádory žaludku diagnóza   mikrobiologie   MeSH
• teoretické modely MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• validační studie MeSH
• Názvy látek
• izotopy uhlíku MeSH
• močovina MeSH