OBJECTIVEThis article aimed to review the incidence of Helicobacter pylori (H. pylori) infection and its therapy.

DATA SOURCESRelevant articles published in English were identified by searching in PubMed from 2000 to 2013, with keywords "H. pylori". Important references from selected articles were also retrieved from Elsevier, Wiley, EBSCO, and SPRINGER. The Chinese articles published were searched from China National Knowledge Infrastructure (CNKI).

STUDY SELECTIONArticles about "prevalence", "gastric carcinoma", "peptic ulcer", "gastroesophageal reflux disease", "functional dyspepsia", "pathogenic mechanism", "therapy", "eradication rate", "antibiotic resistance", and "gene polymorphisms" were selected.

RESULTSThe decreased infection rates of H. pylori could also be linked to the changed disease spectrum, such as the decreased morbidity and recurrence rate of H. pylori-related peptic ulcer, and the increased morbidity of gastroesophageal reflux. Although different treatment regimens have been used for H. pylori infection, the H. pylori eradication rate declined gradually. Due to primary resistance to antibiotics, the gene polymorphism of host and infected strain, and the therapy regimes, H. pylori eradication became even more difficult.

CONCLUSIONSThe prevalence of H. pylori infection had been decreasing, but the rate of eradication failure has dramatically risen in many countries due to resistance to antibiotic. H. pylori therapy in clinical practice is becoming progressively more difficult.

Drug Resistance, Bacterial ; genetics ; Helicobacter Infections ; drug therapy ; epidemiology ; Helicobacter pylori ; drug effects ; genetics ; pathogenicity ; Humans

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

Eradication of Helicobacter pylori is recommended for the management of various gastric diseases, including peptic ulcers and mucosa-associated lymphoid tissue lymphoma. Because of the increasing prevalence of antibiotic resistance, the eradication rates of antibiotic-based therapies have decreased. Therefore, alternative treatments should be considered. The antibacterial properties of fatty acids (FAs) have been investigated in various organisms, including H. pylori. Some FAs, particularly polyunsaturated FAs, have been shown to have bactericidal activity against H. pylori in vitro; however, their antibacterial effects in vivo remain controversial. Poor solubility and delivery of FAs may be important reasons for this discrepancy. Recently, a series of studies demonstrated the antibacterial effects of a liposomal formulation of linolenic acid against H. pylori, both in vitro and in vivo. Further research is needed to improve the bioavailability of FAs and apply them in clinical use.
Animals ; Anti-Bacterial Agents/administration & dosage/*therapeutic use ; Drug Delivery Systems ; Fatty Acids/administration & dosage/*therapeutic use ; Helicobacter Infections/diagnosis/*drug therapy/microbiology ; Helicobacter pylori/*drug effects/pathogenicity ; Humans ; Liposomes ; Treatment Outcome

BACKGROUNDInfection with Helicobacter pylori (H. pylori) may lead to chronic inflammation of the stomach epithelium, mucosal atrophy, imbalance of proliferation and apoptosis of epithelial cells; resulting in chronic gastritis, peptic ulcer, gastric cancer, and many other clinical outcomes. Why and how H. pylorus leads to gastric cancer is not clear yet. Through in vitro experiments, this study evaluated the effects of broth culture filtrate protein (BCF-P) from the supernatant of liquid culture media of H. pylori on proliferation and apoptosis of immortalized human gastric epithelial cell lines (GES-1) and gastric cancer cell lines (AGS).

METHODSFor the study, GES-1 and AGS cell lines mix with BCF-P and epidermal growth factor (EGF). MTT assay and flow cytometry (FCM) determined the levels of proliferation and apoptosis. Detected expression levels of cyclooxygenase-2 (COX-2) and Fas mRNA by reverse transcription (RT)-PCR. Also did analysis of the effects of BCF-P on epidermal growth factor receptor (EGFR) tyrosine kinase activity of GES-1 and AGS cells by non-radioactive enzyme-linked assay. The Student's t test and one-way analysis of variance (ANOVA) were used for statistical analysis.

RESULTSBCF-P inhibited proliferation of GES-1 and AGS cells in a concentration-dependent manner. The inhibition rates are respectively 68.7% in AGS and 61.4% in GES-1. With the same dose and time for inhibiting the proliferation, BCF-P failed to induce apoptosis of GES-1 and AGS cells. Effects of BCF-P reduced the expression of Fas mRNA of GES-1 and AGS cells (P < 0.05). This is consistent with the effects of EGF. BCF-P reduced the expression of COX-2 mRNA of AGS cells (P < 0.05). This is opposite to the effects of EGF (P < 0.05). Effects of BCF-P improved more than three times the EGFR tyrosine kinase activity of GES-1 and AGS cells.

CONCLUSIONSBCF-P inhibited the proliferation of AGS and GES-1 cells in vitro, unrelated to apoptosis. Effects of BCF-P on gastric epithelial cells in vitro are not equivalent to that of EGF.

Apoptosis ; drug effects ; Bacterial Proteins ; toxicity ; Cell Proliferation ; drug effects ; Culture Media ; Cyclooxygenase 2 ; genetics ; Epidermal Growth Factor ; pharmacology ; Gastric Mucosa ; drug effects ; pathology ; HeLa Cells ; Helicobacter pylori ; pathogenicity ; Humans ; RNA, Messenger ; analysis ; fas Receptor ; genetics

OBJECTIVETo develop an oligonucleotide microarray-based method for the simultaneous detection of Helicobacter pylori (Hp) infection, virulence-associated genotypes, and drug resistance.

METHODSHp was classified into cagA + and cagA- genotypes based on its virulence. Clarithromycin-resistance of Hp was identified by existence of point mutations in 23S rRNA. We constructed an oligonucleotide microarray chip to simultaneously diagnose Hp infection and detect its virulence-associated genotypes and mutations associated with clarithromycin-resistance. The diagnostic accuracy of the constructed microarray was tested with templates of wild type and mutated type.

RESULTSThe oligonucleotide chip accurately detected cagA + and cagA- genotypes of Hp, as well as four common point mutations in 23S rRNA related to clarithromycin-resistance.

CONCLUSIONOligonucleotide microarray chip can be used to diagnose Hp infection and test its virulence-associated genotypes and drug resistance simultaneously.

Anti-Bacterial Agents ; pharmacology ; Clarithromycin ; pharmacology ; Drug Resistance, Bacterial ; Genotype ; Helicobacter pylori ; drug effects ; genetics ; pathogenicity ; In Vitro Techniques ; Microbial Sensitivity Tests ; Oligonucleotide Array Sequence Analysis ; Point Mutation ; Polymerase Chain Reaction ; Virulence

BACKGROUNDHelicobacter pylori (H. pylori) frequently colonizes the stomach. Gastroesophageal reflux disease (GERD) is a common and costly disease. But the relationship of H. pylori and GERD is still unclear. This study aimed to explore the effect of H. pylori and its eradication on reflux esophagitis therapy.

METHODSPatients diagnosed with reflux esophagitis by endoscopy were enrolled; based on rapid urease test and Warth-Starry stain, they were divided into H. pylori positive and negative groups. H. pylori positive patients were randomly given H. pylori eradication treatment for 10 days, then esomeprazole 20 mg bid for 46 days. The other patients received esomeprazole 20 mg bid therapy for 8 weeks. After treatment, three patient groups were obtained: H. pylori positive eradicated, H. pylori positive uneradicated, and H. pylori negative. Before and after therapy, reflux symptoms were scored and compared. Healing rates were compared among groups. The χ2 test and t-test were used, respectively, for enumeration and measurement data.

RESULTSThere were 176 H. pylori positive (with 92 eradication cases) and 180 negative cases. Healing rates in the H. pylori positive eradicated and H. pylori positive uneradicated groups reached 80.4% and 79.8% (P = 0.911), with reflux symptom scores of 0.22 and 0.14 (P = 0.588). Healing rates of esophagitis in the H. pylori positive uneradicated and H. pylori negative groups were, respectively, 79.8% and 82.2% (P = 0.848); reflux symptom scores were 0.14 and 0.21 (P = 0.546).

CONCLUSIONSBased on esomeprazole therapy, H. pylori infection and eradication have no significant effect on reflux esophagitis therapy.

Adolescent ; Adult ; Aged ; Amoxicillin ; therapeutic use ; Esomeprazole ; therapeutic use ; Esophagitis, Peptic ; drug therapy ; etiology ; microbiology ; Female ; Gastroesophageal Reflux ; drug therapy ; etiology ; microbiology ; Helicobacter Infections ; complications ; drug therapy ; Helicobacter pylori ; drug effects ; pathogenicity ; Humans ; Male ; Middle Aged ; Tinidazole ; therapeutic use ; Young Adult

Helicobacter pylori (H. pylori) induces the activation of nuclear factor-kB (NF-kappaB) and cytokine expression in gastric epithelial cells. The Janus kinase/signal transducers and activators of transcription (Jak/Stat) cascade is the inflammatory signaling in various cells. The purpose of the present study is to determine whether H. pylori-induced activation of NF-kappaB and the expression of interleukin-8 (IL-8) are mediated by the activation of Jak1/Stat3 in gastric epithelial (AGS) cells. Thus, gastric epithelial AGS cells were infected with H. pylori in Korean isolates (HP99) at bacterium/cell ratio of 300:1, and the level of IL-8 in the medium was determined by enzyme-linked immonosorbent assay. Phospho-specific and total forms of Jak1/Stat3 and IkappaBalpha were assessed by Western blot analysis, and NF-kappaB activation was determined by electrophoretic mobility shift assay. The results showed that H. pylori induced the activation of Jak1/Stat3 and IL-8 production, which was inhibited by a Jak/Stat3 specific inhibitor AG490 in AGS cells in a dose-dependent manner. H. pylori-induced activation of NF-kappaB, determined by phosphorylation of IkappaBalpha and NF-kappaB-DNA binding activity, were inhibited by AG490. In conclusion, Jak1/Stat3 activation may mediate the activation of NF-kappaB and the expression of IL-8 in H. pylori-infected AGS cells. Inhibition of Jak1/Stat3 may be beneficial for the treatment of H. pylori-induced gastric inflammation, since the activation of NF-kappaB is inhibited and inflammatory cytokine expression is suppressed.
Blotting, Western ; DNA, Bacterial/analysis/genetics ; Epithelial Cells/metabolism ; Gastric Mucosa/drug effects/*immunology/microbiology ; Gene Expression Regulation/drug effects/*immunology ; Gene Expression Regulation, Bacterial ; Helicobacter Infections/immunology/*metabolism ; Helicobacter pylori/genetics/pathogenicity/*physiology ; Humans ; Interleukin-8/genetics/*metabolism ; Janus Kinase 1 ; NF-kappa B/biosynthesis/*metabolism ; Phosphorylation ; RNA, Messenger/metabolism ; STAT3 Transcription Factor ; Signal Transduction/genetics

Helicobacter pylori (H. pylori) induces the activation of nuclear factor-kB (NF-kappaB) and cytokine expression in gastric epithelial cells. The Janus kinase/signal transducers and activators of transcription (Jak/Stat) cascade is the inflammatory signaling in various cells. The purpose of the present study is to determine whether H. pylori-induced activation of NF-kappaB and the expression of interleukin-8 (IL-8) are mediated by the activation of Jak1/Stat3 in gastric epithelial (AGS) cells. Thus, gastric epithelial AGS cells were infected with H. pylori in Korean isolates (HP99) at bacterium/cell ratio of 300:1, and the level of IL-8 in the medium was determined by enzyme-linked immonosorbent assay. Phospho-specific and total forms of Jak1/Stat3 and IkappaBalpha were assessed by Western blot analysis, and NF-kappaB activation was determined by electrophoretic mobility shift assay. The results showed that H. pylori induced the activation of Jak1/Stat3 and IL-8 production, which was inhibited by a Jak/Stat3 specific inhibitor AG490 in AGS cells in a dose-dependent manner. H. pylori-induced activation of NF-kappaB, determined by phosphorylation of IkappaBalpha and NF-kappaB-DNA binding activity, were inhibited by AG490. In conclusion, Jak1/Stat3 activation may mediate the activation of NF-kappaB and the expression of IL-8 in H. pylori-infected AGS cells. Inhibition of Jak1/Stat3 may be beneficial for the treatment of H. pylori-induced gastric inflammation, since the activation of NF-kappaB is inhibited and inflammatory cytokine expression is suppressed.
Blotting, Western ; DNA, Bacterial/analysis/genetics ; Epithelial Cells/metabolism ; Gastric Mucosa/drug effects/*immunology/microbiology ; Gene Expression Regulation/drug effects/*immunology ; Gene Expression Regulation, Bacterial ; Helicobacter Infections/immunology/*metabolism ; Helicobacter pylori/genetics/pathogenicity/*physiology ; Humans ; Interleukin-8/genetics/*metabolism ; Janus Kinase 1 ; NF-kappa B/biosynthesis/*metabolism ; Phosphorylation ; RNA, Messenger/metabolism ; STAT3 Transcription Factor ; Signal Transduction/genetics

BACKGROUNDHelicobacter pylori (Hp) is a common and potentially curable cause of gastric mucosa lesion. This study investigated the relationship of Hp infection with histological changes in gastric mucosa and gastric cancer in Hp-positive patients compared with Hp-eradication patients followed up for ten years.

METHODSFrom an initial group of 1 006 adults, 552 Hp-positive subjects were randomly assigned to a treatment group (T; n = 276) or a placebo group (P; n = 276). In the randomized, double-blind, placebo-controlled, parallel trial, T group subjects received oral doses of omeprazole, amoxicillin and clarithromycin for 1 week; those in the P group received a placebo. One month after treatment ended, a 13C urea breath test was performed, and Hp was undetectable in 88.89% of the T group. All subjects were followed at 1, 5, 8, and 10 years after treatment, with endoscopy and biopsies for histological examination.

RESULTSGastric mucosa inflammation was significantly milder in the T group than that in the P group one year after Hp eradication and this persisted for 10 years. Glandular atrophy and intestinal metaplasia (IM) had deteriorated in both groups during ten years. However, the increased score of glandular atrophy at both the gastric antrum and corpus, and IM only at the gastric antrum, in the P group was more obvious than that in the T group. During the 10 years, 9 patients were diagnosed with gastric cancer (2 in the T group; 7 in the P group; P = 0.176). When mucosal atrophy was absent at the gastric antrum and corpus when entering the study, the incidence of gastric cancer in the P group (n = 6) was much higher than that in the T group (n = 0, P = 0.013).

CONCLUSIONSHp eradication may significantly diminish and help halt progression of gastric mucosal inflammation and delay the development of IM and atrophy gastritis. Hp eradication is helpful for reducing the risk for gastric cancer, especially in the early stage of Hp infection.

Adult ; Aged ; Amoxicillin ; therapeutic use ; Anti-Bacterial Agents ; therapeutic use ; Clarithromycin ; therapeutic use ; Double-Blind Method ; Female ; Follow-Up Studies ; Gastric Mucosa ; drug effects ; pathology ; Gastritis, Atrophic ; diagnosis ; drug therapy ; Helicobacter Infections ; drug therapy ; Helicobacter pylori ; pathogenicity ; Humans ; Male ; Middle Aged ; Omeprazole ; therapeutic use ; Stomach Neoplasms ; diagnosis ; prevention & control

BACKGROUND/AIMS: DNA double strand breaks (DSB) is one of the critical types of DNA damage. If unrepaired, DSB is accumulated in the nucleus of cells, the cells become apoptotic or transform to tumor by way of genomic instability. Some of malignant cancers and its premalignant lesions were proven to have DSB in their nuclei. There was no report that Helicobacter pylori (H. pylori), the gastric carcinogen, induce DNA DSB in gastric epithelium in vivo. The aim of this study was to investigate whether H. pylori induce DSB in the gastric epithelial cells of chronic gastritis. METHODS: Immunohistochemical stains were performed for the DSB markers, phospho-53BP1 and gammaH2AX, in the gastric epithelium derived from 44 peptic ulcer disease patients before and after H. pylori eradication. DNA fragmentation assay was performed in the cell line to investigate the DNA damage by H. pylori infection. RESULTS: The mean expression score of gammaH2AX was significantly higher in the H. pylori infected gastric epithelium as compared to the H. pylori eradicated gastric epithelium (8.8+/-5.5 vs. 6.2+/-5.3 respectively; p=0.008). The expression score of phospho-53BP1 between before and after eradication of H. pylori was not statistically different, but tended to be higher in H. pylori infection. DNA fragmentation was developed significantly more in the cell lines after infection with H. pylori. CONCLUSIONS: DSB of DNA damage was typical feature of H. pylori infection in the gastric epithelium.
Adult ; Aged ; Aged, 80 and over ; Anti-Bacterial Agents/therapeutic use ; Cell Line, Tumor ; DNA/metabolism ; *DNA Breaks, Double-Stranded ; Female ; Gastric Mucosa/*metabolism ; Helicobacter Infections/drug therapy/*metabolism ; Helicobacter pylori/*drug effects/pathogenicity ; Histones/genetics/metabolism ; Humans ; Immunohistochemistry ; Intracellular Signaling Peptides and Proteins/genetics/metabolism ; Male ; Middle Aged ; Peptic Ulcer/genetics/pathology