Objective To evaluate the gastric microbiome in patients with chronic superficial gastritis (CSG) and intestinal metaplasia (IM) and investigate the influence of Helicobacter pylori (H. pylori) on the gastric microbiome. Methods Gastric mucosa tissue samples were collected from 54 patients with CSG and IM, and the patients were classified into the following four groups based on the state of H. pylori infection and histology: H. pylori-negative CSG (n=24), H. pylori-positive CSG (n=14), H. pylori-negative IM (n=11), and H. pylori-positive IM (n=5). The gastric microbiome was analyzed by 16S rRNA gene sequencing. Results H. pylori strongly influenced the bacterial abundance and diversity regardless of CSG and IM. In H. pylori-positive subjects, the bacterial abundance and diversity were significantly lower than in H. pylori-negative subjects. The H. pylori-negative groups had similar bacterial composition and bacterial abundance. The H. pylori-positive groups also had similar bacterial composition but different bacterial relative abundance. The relative abundance of Neisseria, Streptococcus, Rothia, and Veillonella were richer in the I-HP group than in G-HP group, especially Neisseria (t=175.1, P<0.001). Conclusions The gastric microbial abundance and diversity are lower in H. pylori- infected patients regardless of CSG and IM. Compared to H. pylori-positive CSG group and H. pylori-positive IM, the relative abundance of Neisseria, Streptococcus, Rothia, and Veillonella is higher in H. pylori-positive patients with IM than in H. pylori-positive patients with CSG, especially Neisseria.
Gastric Mucosa/microbiology* ; Gastritis, Atrophic/microbiology* ; Gastrointestinal Microbiome/genetics* ; Helicobacter Infections/microbiology* ; Helicobacter pylori/genetics* ; Humans ; Metaplasia ; RNA, Ribosomal, 16S/genetics* ; Stomach Neoplasms

ObjectiveGastroscopy combined with gastric mucosa biopsies is currently regarded as a gold standard for diagnosis of gastric cancer. However, its application is restricted in clinical practice due to its invasive property. A new noninvasive population screening process combining the assay of anti-Helicobacter pylori antibody and serum pepsinogen (PG) (ABC method) is adopted to recognize the high-risk patients for further endoscopy examination, avoiding the unnecessary gastroscopy for most population and saving the cost consumption for mass screening annually. Nevertheless, controversies exist for the grouping of ABC method and the intervals of gastroscopy surveillance for each group. In this review, we summarized these popular concerned topics for providing useful references to the healthcare practitioner in clinical practice.

Data SourcesThe PubMed databases were systematically searched from the inception dates to November 22, 2017, using the keywords "Helicobacter pylori," "Pepsinogens," and "Stomach Neoplasms."

Study SelectionOriginal articles and reviews on the topics were selected.

ResultsAnti-H. pylori antibody and serum PG concentration showed significant changes under the different status of H. pylori infection and the progression of atrophic gastritis, which can be used for risk stratification of gastric cancer in clinic. In addition, anti-H. pylori antibody titer can be used for further risk stratification of gastric cancer contributing to determine better endoscopy surveillance interval.

ConclusionsThe early detection and diagnosis of gastric cancer benefit from the risk stratification, but the cutoff values for H. pylori antibody and serum PG concentration require further modification.

Antibodies, Bacterial ; blood ; immunology ; Gastroscopy ; Helicobacter Infections ; blood ; immunology ; Helicobacter pylori ; immunology ; Humans ; Mass Screening ; methods ; Stomach Neoplasms ; blood ; microbiology

With the widely application of the metagenomics, the relationship between microbiota and disease has become a hot research topic. Understanding the potential association between upper gastrointestinal cancer or precancerous lesions and microbiota may play an important role in the early detection, clinical diagnosis and treatment, and prognostic evaluation of upper gastrointestinal cancer. Therefore, a literature retrieval was conducted by using PubMed, Embase and wanfang databases to summarize the latest research progress in the microbiota of upper gastrointestinal cancer, including oral, esophageal, gastric cancer and precancerous lesions. Lower microbial diversity or richness in esophageal cancer and precancerous lesions and specific prognostic biomarkers for esophageal cancer were found. Lactobacillus richness showed an increase trend during the process from gastritis to gastric cancer. This paper summarizes the progress in the research of potential biological etiology of upper gastrointestinal cancer from the perspective of metagenomics in order to provide evidence on the, prevention and control of upper gastrointestinal cancer.
Esophageal Neoplasms/microbiology* ; Gastrointestinal Microbiome ; Gastrointestinal Neoplasms/microbiology* ; Gastrointestinal Tract/microbiology* ; Humans ; Lactobacillus ; Metagenomics/trends* ; Microbiota ; Precancerous Conditions/microbiology* ; Prognosis ; Research/trends* ; Risk Factors ; Stomach Neoplasms/microbiology*

Gastric dysplasia is a neoplastic lesion and a precursor of gastric cancer. The Padova, Vienna, and World Health Organization classifications were developed to overcome the discrepancies between Western and Japanese pathologic diagnoses and to provide a universally accepted classification of gastric epithelial neoplasia. At present, the natural history of gastric dysplasia is unclear. Much evidence suggests that patients with high-grade dysplasia are at high risk of progression to carcinoma or synchronous carcinoma. Therefore, endoscopic resection is required. Although patients with low-grade dysplasia have been reported to be at low risk of progression to carcinoma, due to the marked histologic discrepancies between forceps biopsy and endoscopic specimens, endoscopic resection for this lesion is recommended, particularly in the presence of other risk factors (large size; depressed gross type; surface erythema, unevenness, ulcer, or erosion; and tubulovillous or villous histology). Helicobacter pylori eradication in patients with dysplasia after endoscopic resection appear to reduce the incidence of metachronous lesions.
Anti-Bacterial Agents/therapeutic use ; Biopsy ; Carcinoma in Situ/classification/microbiology/*pathology/*surgery ; Disease Progression ; *Gastrectomy/adverse effects/methods ; Gastric Mucosa/microbiology/*pathology/*surgery ; Gastroscopy ; Helicobacter Infections/drug therapy/microbiology ; Helicobacter pylori/drug effects ; Humans ; Neoplasm Grading ; Precancerous Conditions/classification/microbiology/*pathology/*surgery ; Predictive Value of Tests ; Risk Factors ; Stomach Neoplasms/classification/microbiology/*pathology/*surgery ; Treatment Outcome

Although the age-adjusted incidence of gastric cancer is declining, the absolute number of new cases of gastric cancer is increasing due to population growth and aging. An effective strategy is needed to prevent this deadly cancer. Among the available strategies, screen-and-treat for Helicobacter pylori infection appears to be the best approach to decrease cancer risk; however, implementation of this strategy on the population level requires a systematic approach. The program also must be integrated into national healthcare priorities to allow the limited resources to be most effectively allocated. Implementation will require adoption of an appropriate screening strategy, an efficient delivery system with a timely referral for a positive test, and standardized treatment regimens based on clinical efficacy, side effects, simplicity, duration, and cost. Within the population, there are subpopulations that vary in risk such that a "one size fits all" approach is unlikely to be ideal. Sensitivity analyses will be required to identify whether the programs can be utilized by heterogeneous populations and will likely require adjustments to accommodate the needs of subpopulations.
Health Priorities ; Helicobacter Infections/complications/diagnosis/microbiology/*therapy ; Helicobacter pylori ; Humans ; Mass Screening ; Stomach Neoplasms/microbiology/*prevention & control

BACKGROUND/AIMS: Controversy exists regarding the characteristics of Helicobacter pylori infection-negative gastric cancer (HPIN-GC). The aim of this study was to evaluate clinicopathologic features of HPIN-GC compared to H. pylori infection-positive gastric cancer (HPIP-GC) using a comprehensive analysis that included genetic and environmental factors. METHODS: H. pylori infection status of 705 resectable gastric cancer patients was determined by the rapid urease test, testing for anti-H. pylori antibodies, histologic analysis and culture of gastric cancer tissue samples, and history of H. pylori eradication. HPIN-GC was defined as gastric cancer that was negative for H. pylori infection based on all five methods and that had no evidence of atrophy in histology or serology. RESULTS: The prevalence of HPIN-GC was 4% (28/705). No significant differences with respect to age, sex, smoking, drinking, family history of gastric cancer or obesity were observed between the two groups. HPIN-GC tumors were marginally more likely to involve the cardia (14.3% for HPIN-GC vs 5.3% for HPIP-GC, p=0.068). The Lauren classification, histology, and TNM stage did not differ according to H. pylori infection status. Microsatellite instability was not different between the two groups, but p53 overexpression in HPIN-GC was marginally higher than in HPIP-GC (56.0% for HPIN-GC vs 37.0% for HPIP-GC, p=0.055). CONCLUSIONS: The prevalence of HPIN-GC was extremely low, and its clinicopathologic characteristics were similar to HPIP-GC.
Antibodies, Bacterial/analysis ; Female ; Helicobacter Infections/*complications/epidemiology/microbiology ; *Helicobacter pylori ; Humans ; Male ; Middle Aged ; Prevalence ; Prospective Studies ; Republic of Korea/epidemiology ; Stomach Neoplasms/epidemiology/*microbiology/*pathology/surgery ; Urease/analysis

Most gastric cancers are caused by infection with the common human bacterial pathogen, Helicobacter pylori. It is now accepted that gastric cancer can be prevented and virtually eliminated by H. pylori eradication and this knowledge was responsible for country-wide H. pylori eradication combined with secondary cancer prevention for those with residual risk that was introduced in Japan in 2013. Korea is a high H. pylori prevalence and high gastric cancer incidence country and a good candidate for a gastric cancer elimination program. The presence of an H. pylori infection is now considered as an indication for treatment of the infection. However, antimicrobial drug resistance is common among H. pylori in Korea making effective therapy problematic. Country-wide studies of the local and regional antimicrobial resistance patterns are needed to choose the most appropriate therapies. H. pylori and gastric cancer eradication can be both efficient and cost effective making it possible and practical to make Korea H. pylori and gastric cancer free. There is no reason to delay.
Anti-Bacterial Agents/*therapeutic use ; Disease Eradication ; Drug Resistance, Bacterial ; Helicobacter Infections/*drug therapy/epidemiology/microbiology ; Helicobacter pylori/*drug effects/growth & development ; Humans ; Prevalence ; Primary Prevention/*methods ; Republic of Korea/epidemiology ; Risk Assessment ; Risk Factors ; Stomach Neoplasms/epidemiology/microbiology/*prevention & control ; Treatment Outcome

OBJECTIVEAlthough Helicobacter pylori (H. pylori) is considered as the main etiological factor for gastric cancer, the strategy of screening and treating the oncogenic bacterium is still controversial. The objective was to evaluate the status and progress of the cognition about the relationship between H. pylori infection and gastric cancer from a clinical aspect.

DATA SOURCESThe data used in this review were mainly from the PubMed articles published in English from 1984 to 2015.

STUDY SELECTIONClinical research articles were selected mainly according to their level of relevance to this topic.

RESULTSGastric cancer is the fifth most common malignancy and the third leading cause of cancer deaths worldwide. The main etiological factor for gastric cancer is H. pylori infection. About 74.7-89.0% gastric cancer was related to H. pylori infection. Up to date, some regional gastric cancer prevention programs including the detection and treatment of H. pylori infection are under way. Current data obtained from the randomized controlled trials suggest that population-based H. pylori screening and treatment is feasible and cost-effective in preventing gastric cancer; however, a population-based H. pylori eradication campaign would potentially lead to bacterial resistance to the corresponding antibiotics, as well as a negative impact on the normal flora.

CONCLUSIONSThe important questions of feasibility, program costs, appropriate target groups for intervention, and the potential harm of mass therapy with antibiotics must first be answered before implementing any large-scale program.

Anti-Bacterial Agents ; therapeutic use ; Cost-Benefit Analysis ; Helicobacter Infections ; economics ; prevention & control ; Helicobacter pylori ; drug effects ; pathogenicity ; Humans ; Mass Screening ; economics ; Stomach Neoplasms ; microbiology ; prevention & control

BACKGROUND/AIMS: Helicobacter pylori cytotoxin-associated gene A (CagA) has been suggested to be involved in the inactivation of Runt-related transcription factor 3 (RUNX3), a known gastric carcinoma tumor suppressor gene. It remains unclear how H. pylori CagA initiates or maintains RUNX3 promoter methylation and inactivates its protein expression in gastric carcinoma. METHODS: RUNX3 promoter methylation status, RUNX3 expression, and H. pylori CagA were investigated in 76 sample pairs of gastric carcinoma tissue. The patients' medical records were reviewed. The association between RUNX3 methylation or loss of RUNX3 expression and clinicopathologic variables according to H. pylori CagA status were investigated. RESULTS: In gastric carcinoma patients with H. pylori CagA-positive infection, RUNX3 methylation did not show association with lymphatic invasion, venous invasion, and TNM stages. However RUNX3 methylation was observed more frequently in poorly differentiated adenocarcinoma and signet ring cell carcinoma (77.8% vs. 20.0%, p=0.023) in early stage. In gastric carcinoma patients with H. pylori CagA-positive infection, loss of RUNX3 expression did not show association with lymphatic invasion, venous invasion, and TNM stages. However loss of RUNX3 expression was observed more frequently in early gastric carcinoma than in advanced gastric carcinoma (84.2% vs. 75.0%, p=0.51), but this difference was not significant. CONCLUSIONS: In gastric carcinoma patients with H. pylori CagA-positive infection, RUNX3 methylation or loss of RUNX3 expression did not show correlation with lymphovascular invasion and TNM stages. In early gastric carcinoma patients with H. pylori CagA-positive infection, RUNX3 methylation was observed more in poorly differentiated adenocarcinoma and signet ring cell carcinoma.
Adult ; Aged ; Aged, 80 and over ; Antigens, Bacterial/*metabolism ; Bacterial Proteins/*metabolism ; Cell Line, Tumor ; Core Binding Factor Alpha 3 Subunit/genetics/*metabolism ; Female ; *Gene Expression Regulation, Neoplastic ; Helicobacter Infections/complications/microbiology ; Helicobacter pylori/isolation & purification/*metabolism ; Humans ; Immunohistochemistry ; Lymphatic Metastasis ; Male ; Methylation ; Middle Aged ; Neoplasm Staging ; Promoter Regions, Genetic ; Retrospective Studies ; Stomach Neoplasms/complications/microbiology/*pathology

OBJECTIVETo investigate the correlation between infection with L-form of Helicobacter pylori (Hp-L) and the expressions of macrophage migration inhibition factor (MIF), matrix metalloproteinase 9 (MMP9), and vascular endothelial growth factor (VEGF) in gastric cancer.

METHODSHp-L was examined in 80 gastric carcinoma and 50 adjacent normal tissues by Gram staining and immunohistochemical staining, and the expressions of MIF, MMP9 and VEGF were detected by immunohistochemical staining; the expression of MIF mRNA was detected by RT-PCR and the expression of MIF, MMP9 and VEGF proteins were detected by Western blotting in 30 fresh gastric cancer tissues and the corresponding adjacent tissues.

RESULTSOf the 80 gastric carcinoma tissues, 57 (71.25%) showed Hp-L positivity detected by both Gram staining and immunohistochemical staining, as compared with a rate of only 14% in the adjacent normal tissues (P<0.05). The gastric carcinoma tissues showed higher expression levels of MIF, MMP9 and VEGF proteins than the corresponding adjacent normal mucosa; the positivity MIF, MMP-9 and VEGF proteins were significantly higher in Hp-L-positive gastric carcinoma than in Hp-L-negative cases (P<0.05). Positive correlations were found between Hp-L positivity and the expressions of MIF, MMP-9 and VEGF (r=0.598, 0.292, 0.341, respectively, P<0.05). The 30 fresh gastric cancer tissues showed also significantly higher MIF mRNA expression and MIF, MMP-9 and VEGF protein expressions than the adjacent tissues (t=3.729, P<0.01). The expressions of MIF and MMP-9 were also related to the clinicopathological factors including lymph node metastasis and depth of invasion (P<0.05).

CONCLUSIONInfection with L-form of Hp-L can be an important factor that contributes to the invasion and metastasis of gastric carcinoma, the mechanism of which involves up-regulated expressions of MIF, MMP-9 and VEGF.

Adult ; Aged ; Aged, 80 and over ; Female ; Helicobacter Infections ; metabolism ; pathology ; Helicobacter pylori ; Humans ; L Forms ; Lymphatic Metastasis ; Macrophage Migration-Inhibitory Factors ; metabolism ; Male ; Matrix Metalloproteinase 9 ; metabolism ; Middle Aged ; Stomach Neoplasms ; metabolism ; microbiology ; pathology ; Vascular Endothelial Growth Factor A ; metabolism