Functional Analysis of the cag Pathogenicity Island in Helicobacter pylori Isolates from Patients with Gastritis, Peptic Ulcer, and Gastric Cancer

ABSTRACT Helicobacter pylori is the causative agent of a variety of gastric diseases, but the clinical relevance of bacterial virulence factors is still controversial. Virulent strains carrying the cag pathogenicity island (cagPAI) are thought to be key players in disease development. Here, we have compared cagPAI-dependent in vitro responses in H. pylori isolates obtained from 75 patients with gastritis, peptic ulcer, and gastric cancer (n = 25 in each group). AGS gastric epithelial cells were infected with each strain and assayed for (i) CagA expression, (ii) translocation and tyrosine phosphorylation of CagA, (iii) c-Src inactivation, (iv) cortactin dephosphorylation, (v) induction of actin cytoskeletal rearrangements associated with cell elongation, (vi) induction of cellular motility, and (vii) secretion of interleukin-8. Interestingly, we found high but similar prevalences of all of these cagPAI-dependent host cell responses (ranging from 56 to 80%) among the various groups of patients. This study revealed CagA proteins with unique features, CagA subspecies of various sizes, and new functional properties for the phenotypic outcomes. We further showed that induction of AGS cell motility and elongation are two independent processes. Our data corroborate epidemiological studies, which indicate a significant association of cagPAI presence and functionality with histopathological findings in gastritis, peptic ulcer, and gastric cancer patients, thus emphasizing the importance of the cagPAI for the pathogenicity of H. pylori. Nevertheless, we found no significant association of the specific H. pylori-induced responses with any particular patient group. This may indicate that the determination of disease development is highly complex and involves multiple bacterial and/or host factors.

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The correlation between lncRNAs and Helicobacter pylori in gastric cancer

Pathogens and Disease ◽

10.1093/femspd/ftaa004 ◽

2019 ◽

Vol 77 (9) ◽

Author(s):

Narges Dastmalchi ◽

Seyed Mahdi Banan Khojasteh ◽

Mirsaed Miri Nargesi ◽

Reza Safaralizadeh

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Molecular Mechanisms ◽

Gastrointestinal Diseases ◽

Mechanisms Of Action ◽

Molecular Pathways ◽

Gastric Diseases ◽

Non Coding Rnas ◽

H Pylori ◽

The Relationship

ABSTRACT Helicobacter pylori infection performs a key role in gastric tumorigenesis. Long non-coding RNAs (lncRNAs) have demonstrated a great potential to be regarded as effective malignancy biomarkers for various gastrointestinal diseases including gastric cancer (GC). The present review highlights the relationship between lncRNAs and H. pylori in GC. Several studies have examined not only the involvement of lncRNAs in H. pylori-associated GC progression but also their molecular mechanisms of action. Among the pertinent studies, some have addressed the effects of H. pylori infection on modulatory networks of lncRNAs, while others have evaluated the effects of changes in the expression level of lncRNAs in H. pylori-associated gastric diseases, especially GC. The relationship between lncRNAs and H. pylori was found to be modulated by various molecular pathways.

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Prospective Assessment of Helicobacter Pylori Infection and Gastric Pathologies in Sidi Bel Abbes region, Western Algeria

South Asian Journal of Experimental Biology ◽

10.38150/sajeb.7(5).p217-224 ◽

2018 ◽

Vol 7 (5) ◽

pp. 217-224

Author(s):

Zouaouia Chama ◽

Khedoudj Kanoun ◽

Fatima Zohra Elkadi ◽

Kara Turqui Douidi ◽

Noria Harir ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Histological Study ◽

Helicobacter Pylori Infection ◽

University Hospital ◽

Infection Prevalence ◽

Gastric Diseases ◽

Number Of Patients ◽

H Pylori ◽

The Impact

Helicobacter pylori infection concerns half of the world’s population, mainly in developing countries. It causes several gastrodudenal pathologies such as gastritis, ulcer and gastric adenocarcinoma. The aim of our study was to determine the prevalence of H.pylori infection and to assess the impact of different epidemiological factors as well as principal gastric diseases associ-ated to this infection. We underwent a prospective study during 18 months (month 2016-month 2017) which implicated 201 symptomatic patients for gastric fiboptic endoscopy at the level of Sidi Bel Abbes University hospital. We collected patients’ biopsies to perform a histological study and H. pylori culture. H. pylori identification was carried out based on bacteriological and biochemical analysis. The middle age of our population was (47.29 ±15.97ans) and the sex-ratio =0,8. The global prevalence of Helicobacter pylori infection is of 61.2% (123/201). This rate, after a statistic analysis, seems to be significantly related to age. It is particularly high especially for patients belonging to age range (20-30)-(51-60) years. The gender did not affect the infection prevalence that is more frequent in the gastritis case. We noticed also that HP infection prevalence was important in SBA the hospital. The range age (20-30)-(51-60) years had the highest prevalence of H. pylori and of gastritis which might be a risky ground of gastric cancer appearance. The ulcer pathology maximal rate concerned the group of 51 to 60 years. Above this age, this rate dropped whereas the number of patients suffering from gastric cancer, which presents an important rate in our study, increase for the group of 61-70 years.

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Helicobacter pyloriAnti-CagA Antibodies: Prevalence in Symptomatic and Asymptomatic Subjects in Turkey

Canadian Journal of Gastroenterology ◽

10.1155/2002/589087 ◽

2002 ◽

Vol 16 (8) ◽

pp. 527-532 ◽

Cited By ~ 13

Author(s):

M Fatih Abasiyanik ◽

Ersan Sander ◽

Barik A Salih

Keyword(s):

Gastric Cancer ◽

Duodenal Ulcer ◽

Helicobacter Pylori ◽

Peptic Ulcer ◽

Chronic Gastritis ◽

Molecular Weights ◽

Cancer Antigens ◽

Gastroduodenal Disease ◽

H Pylori ◽

Asymptomatic Subjects

BACKGROUND: Several reports have shown the prevalence of anti-CagA antibodies to be associated with the development of peptic ulcer diseases, while others have indicated that there is no such association.AIM: To examine the prevalence of antibodies to CagA and otherHelicobacter pyloriantigens in symptomatic and asymptomatic subjects in Turkey.SUBJECTS AND METHODS: Sixty-six symptomatic subjects, 16 to 74 years of age, were examined forH pyloriby biopsy-based tests and ELISA. One hundred nineteen asymptomatic subjects, 20 to 65 years of age, were also tested serologically for the presence ofH pylori. Samples from both groups that were found to be positive forH pyloriby ELISA were then tested by immunoblotting.RESULTS: Fifty-four (82%) symptomatic subjects and 76 (64%) asymptomatic subjects were found to beH pylori-positive by ELISA. Samples from 30 symptomatic subjects who were found to beH pylori-positive by ELISA were analyzed by immunoblotting. Antibodies to CagA (116 kDa) antigen were detected in immunoblots of 11 of 14 (79%) with chronic gastritis, 12 of 13 (92%) with duodenal ulcer and three of three (100%) with gastric cancer. Antigens of the following molecular weights were also detected in these 30 subjects: 89 kDa (VacA) in 21 (70%), 37 kDa in 21 (70%), 35 kDa in 19 (63%), 30 kDa in 27 (90%) and 19.5 kDa in 19 (63%). Immunoblots of 40 ELISA-positive asymptomatic subjects showed that 33 (83%) had antibodies to CagA antigen, 26 (65%) to VacA antigen, 30 (75%) to a 37 kDa antigen, 30 (75%) to a 35 kDa antigen, 39 (98%) to a 30 kDa antigen and 36 (90%) to a 19.5 kDa antigen.CONCLUSIONS: Antibodies to CagA antigen were prevalent in both groups, regardless of the presence of gastroduodenal disease.

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The organization of Helicobacter pylori cag-pathogenicity island (cagPAI) genes in multiracial population with histopathological changes of gastric mucosa

10.21203/rs.2.9601/v1 ◽

2019 ◽

Author(s):

Alfizah Hanafiah ◽

Shaza Azlin Razak ◽

Hui-min Neoh ◽

Noraziah Mohamad Zin ◽

Bruno S. Lopes

Keyword(s):

Helicobacter Pylori ◽

Gastric Mucosa ◽

Pathogenicity Island ◽

Type Iv Secretion ◽

Virulence Determinants ◽

Gastric Diseases ◽

Cag Pathogenicity Island ◽

Type Iv ◽

Inflammatory Score ◽

H Pylori

Abstract Background: Helicobacter pylori is a Gram-negative bacillus that colonises only the mucus layer of the human stomach and is implicated in gastric diseases. Virulent H. pylori harbouring cag-pathogenicity island (cagPAI) which encodes genes for type IV secretion system (T4SS) and CagA protein is one of the major virulence determinants involved in disease development. We examined the entire cagPAI genes in 95 H. pylori isolates from a multiracial population and examined the intactness of cagPAI region with histopathological scores of the gastric mucosa. Results: 95.8% of H. pylori isolates were cagPAI-positive with 23.2% having an intact cagPAI, whereas 72.6% had a partial/rearranged cagPAI. In our study, cag2 and cag4 were found to be significantly higher in H. pylori isolated from Malays, whereas cag4 was predominant in Chinese isolates. We also detected cag24 in significantly high proportion in isolates from the Malays and the Indians compared to the Chinese isolates. The intactness of cagPAI region showed an association with histopathological scores of the gastric mucosa. Significant association was observed between H. pylori harbouring partial cagPAI and higher density of H. pylori and neutrophil activity, whereas strains which lacked cagPAI was associated with higher inflammatory score. Conclusions: The screening of the entire cagPAI genes provides an accurate overview of the cagPAI organisation in H. pylori isolates in a multiracial population. The genotypes of H. pylori strains with various cagPAI rearrangement associated with patients’ ethnicities and histopathological scores might contribute to the pathogenesis of H. pylori infection in a multi-ethnic population.

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Helicobacter Pylori Induce Gastric Upset

Journal of Medical Research and Surgery ◽

10.52916/jmrs214055 ◽

2021 ◽

pp. 1-1

Author(s):

Hazim Abdul Rahman Alhit

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Serum Antibody ◽

Endoscopic Biopsy ◽

Helicobacter Pylori Infection ◽

Gastric Epithelium ◽

Gastric Diseases ◽

Heterogeneous Distribution ◽

Cytotoxin Associated Gene A ◽

H Pylori

Editorial: Helicobacter pylori is a micro-aerophilic, helical-form gramnegative aggressive bacteria. Accordingly, the idiom “Helico” intimates its helical appearance, “bacter” symbolizes bacteria, while “pylori” denotes stomach due to the first and common site of this bacteria living. Further, Marshall B. and Warren R. observed and described it in 1982. Then, the followed investigators studied this bacterium in detail with its consequences and complexities [1]. Gastric upset (Indigestion), dyspepsia: means impaired gastric digestion. Accordingly, the patient complains of upper abdominal pain, heartburn, belching, nausea, even feeling earlier gastric fullness than expected while eating. Furthermore, there are many causes of indigestion like gastroesophageal reflux disease, ulcer disease, gastritis, and even gastric cancer. Hence, unexplained recent onset dyspepsia in older people may need additional examinations. Moreover, one of the common causes is Helicobacter pylori infection, which needs laboratory and endoscopic examination [2]. Argument Many theories investigated the etiology and pathogenesis of Helicobacter pylori infection, concerning chronic or acute gastritis. Hence, gastric upset is the main presentation of both types of gastritis. Evidences The genotype is valuable in determining the dominant Helicobacter pylori strains as the isolates were different genetically plus heterogeneous distribution. Accordingly, the vac and cag markers operate a significant function in defining clinical consequences. These virulence agents are present in a subset of Helicobacter pylori strains isolates like cagA, iceA, vacA, and ureC. Moreover, the cagA causes cytotoxins induction by the gastric epithelial cell as Interleukin 8 [3]. The molecular intercommunication researches exhibit that the act of acarus calamus in hindering biofilm formation in Helicobacter pylori is due to the inhibitory impact of phytobio-active component, β-sitosterol, on the quorum sensing molecules-ToxB, PhnB, DnaA, plus Sip. Consequently, this opinion may suggest the molecular mechanism of Helicobacter pylori in producing the acidrelated complaints and gives a clue to a new therapy [4]. Helicobacter pylori infection causes lncRNA risk impression linked to H. pylori in gastric cancer patients and can prognosticate the prediction of these patients [5]. There was a close relationship between raised serum IgE levels in Helicobacter pylori infected patients [6]. Counterargument The laboratory investigations of Helicobacter pylori infection depend on several factors like the fluctuations of serum antibody titers in a time series, the antigene detection in stool tests, the false-positive results of lab tests, or the manner of endoscopic biopsy collection. Furthermore, other factors like the variations in Cytotoxin-Associated Gene A (CagA) in East Asian patients. Moreover, the gastric nodularity or atrophy, the patient’s age, the severity of the gastric mucosal infection are causes of variations in Helicobacter pylori detection at the time of the investigation [7]. Refutation The significant markers of H. pylori, the presence of the vacuolating cytotoxin (vacA), the cytotoxin-associated gene A (cagA), which induced by the direct communication with gastric epithelium factor antigen (iceA gene), and the presence of urease C gene (ureC). Consequently, all these factors play the principal factors in deciding the gastric consequences of Helicobacter infections. Conclusion Helicobacter pylori induce gastric upset by several mechanisms to form numerous Gastric diseases.

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In VitroInhibition ofHelicobacter pyloriGrowth by Redox Cycling Phenylaminojuglones

Oxidative Medicine and Cellular Longevity ◽

10.1155/2018/1618051 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

Julio Benites ◽

Héctor Toledo ◽

Felipe Salas ◽

Angélica Guerrero ◽

David Rios ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Antibacterial Activity ◽

Active Compound ◽

Metabolic Pathways ◽

Growth Inhibitor ◽

Growth Inhibitors ◽

Design Synthesis ◽

H Pylori

Infection byHelicobacter pyloriincreases 10 times the risk of developing gastric cancer. Juglone, a natural occurring 1,4-naphthoquinone, preventsH. pylorigrowth by interfering with some of its critical metabolic pathways. Here, we report the design, synthesis, andin vitroevaluation of a series of juglone derivatives, namely, 2/3-phenylaminojuglones, as potentialH. pylorigrowth inhibitors. Results show that 5 out of 12 phenylaminojuglones (at 1.5 μg/mL) were 1.5–2.2-fold more active than juglone. Interestingly, most of the phenylaminojuglones (10 out of 12) were 1.1–2.8 fold more active than metronidazole, a knownH. pylorigrowth inhibitor. The most active compound, namely, 2-((3,4,5-trimethoxyphenyl)amino)-5-hydroxynaphthalene-1,4-dione 7, showed significant higher halo of growth inhibitions (HGI = 32.25 mm) to that of juglone and metronidazole (HGI = 14.50 and 11.67 mm). Structural activity relationships of the series suggest that the nature and location of the nitrogen substituents in the juglone scaffold, likely due in part to their redox potential, may influence the antibacterial activity of the series.

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Western-Type Helicobacter pylori CagA are the Most Frequent Type in Mongolian Patients

Cancers ◽

10.3390/cancers11050725 ◽

2019 ◽

Vol 11 (5) ◽

pp. 725 ◽

Cited By ~ 2

Author(s):

Tegshee Tserentogtokh ◽

Boldbaatar Gantuya ◽

Phawinee Subsomwong ◽

Khasag Oyuntsetseg ◽

Dashdorj Bolor ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Cancer Patients ◽

East Asian ◽

Virulent Strains ◽

Virulent Type ◽

High Incidence ◽

Caga Status ◽

H Pylori ◽

Gastric Cancer Patients

Helicobacter pylori infection possessing East-Asian-type CagA is associated with carcinogenesis. Mongolia has the highest mortality rate from gastric cancer. Therefore, we evaluated the CagA status in the Mongolian population. High risk and gastric cancer patients were determined using endoscopy and histological examination. H. pylori strains were isolated from different locations in Mongolia. The CagA subtypes (East-Asian-type or Western-type, based on sequencing of Glu-Pro-Ile-Tyr-Ala (EPIYA) segments) and vacA genotypes (s and m regions) were determined using PCR-based sequencing and PCR, respectively. In total, 368 patients were examined (341 gastritis, 10 peptic ulcer, and 17 gastric cancer). Sixty-two (16.8%) strains were cagA-negative and 306 (83.1%) were cagA-positive (293 Western-type, 12 East-Asian-type, and one hybrid type). All cagA-negative strains were isolated from gastritis patients. In the gastritis group, 78.6% (268/341) had Western-type CagA, 2.9% (10/341) had East-Asian-type, and 18.2% (61/341) were cagA-negative. However, all H. pylori from gastric cancer patients possessed Western-type CagA. Histological analyses showed that East-Asian-type CagA was the most virulent strains, followed by Western-type and cagA-negative strains. This finding agreed with the current consensus. CagA-positive strains were the most virulent type. However, the fact that different CagA types can explain the high incidence of gastric cancer might be inapplicable in Mongolia.

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Cross-sectional study of human coding- and non-coding RNAs in progressive stages of Helicobacter pylori infection

Scientific Data ◽

10.1038/s41597-020-00636-6 ◽

2020 ◽

Vol 7 (1) ◽

Author(s):

Sergio Lario ◽

María J. Ramírez-Lázaro ◽

Aintzane González-Lahera ◽

José L. Lavín ◽

Maria Vila-Casadesús ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Expression Profiles ◽

Gastric Carcinogenesis ◽

Individual Response ◽

Peptic Ulcers ◽

Gastric Diseases ◽

Sequence Of Events ◽

Non Coding Rnas ◽

H Pylori

Abstract Helicobacter pylori infects 4.4 billion individuals worldwide and is considered the most important etiologic agent for peptic ulcers and gastric cancer. Individual response to H. pylori infection is complex and depends on complex interactions between host and environmental factors. The pathway towards gastric cancer is a sequence of events known as Correa’s model of gastric carcinogenesis, a stepwise inflammatory process from normal mucosa to chronic-active gastritis, atrophy, metaplasia and gastric adenocarcinoma. This study examines gastric clinical specimens representing different steps of the Correa pathway with the aim of identifying the expression profiles of coding- and non-coding RNAs that may have a role in Correa’s model of gastric carcinogenesis. We screened for differentially expressed genes in gastric biopsies by employing RNAseq, microarrays and qRT-PCR. Here we provide a detailed description of the experiments, methods and results generated. The datasets may help other scientists and clinicians to find new clues to the pathogenesis of H. pylori and the mechanisms of progression of the infection to more severe gastric diseases. Data is available via ArrayExpress.

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Virulence genes of Helicobacter pylori in the Dominican Republic

Journal of Medical Microbiology ◽

10.1099/jmm.0.075275-0 ◽

2014 ◽

Vol 63 (9) ◽

pp. 1189-1196 ◽

Cited By ~ 18

Author(s):

Seiji Shiota ◽

Modesto Cruz ◽

José A. Jiménez Abreu ◽

Takahiro Mitsui ◽

Hideo Terao ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Peptic Ulcer ◽

Dominican Republic ◽

Infection Rate ◽

Rapid Urease Test ◽

Test Culture ◽

Urease Test ◽

The Status ◽

H Pylori

Although the incidence of gastric cancer in the Dominican Republic is not high, the disease remains a significant health problem. We first conducted a detailed analysis of Helicobacter pylori status in the Dominican Republic. In total, 158 patients (103 females and 55 males; mean age 47.1±16.2 years) were recruited. The status of H. pylori infection was determined based on four tests: rapid urease test, culture test, histological test and immunohistochemistry. The status of cagA and vacA genotypes in H. pylori was examined using PCR and gene sequencing. The overall prevalence of H. pylori infection was 58.9 %. No relationship was found between the H. pylori infection rate and the age range of 17–91 years. Even in the youngest group (patients aged <29 years), the H. pylori infection rate was 62.5 %. Peptic ulcer was found in 23 patients and gastric cancer was found in one patient. The H. pylori infection rate in patients with peptic ulcer was significantly higher than that in patients with gastritis (82.6 versus 54.5 %, P<0.01). The cagA-positive/vacA s1m1 genotype was the most prevalent (43/64, 67.2 %). Compared with H. pylori-negative patients, H. pylori-positive patients showed more severe gastritis. Furthermore, the presence of cagA was related to the presence of more severe gastritis. All CagA-positive strains had Western-type CagA. In conclusion, we found that H. pylori infection is a risk factor for peptic ulcer in the Dominican Republic. Patients with cagA-positive H. pylori could be at higher risk for severe inflammation and atrophy.

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Discovery and Validation of Novel Methylation Markers in Helicobacter pylori-Associated Gastric Cancer

Disease Markers ◽

10.1155/2021/4391133 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Huan Wang ◽

Nian-Shuang Li ◽

Cong He ◽

Chuan Xie ◽

Yin Zhu ◽

...

Keyword(s):

Gene Expression ◽

Gastric Cancer ◽

Dna Methylation ◽

Helicobacter Pylori ◽

Gene Expression Data ◽

Functional Enrichment ◽

Expression Data ◽

H Pylori

Previous studies have shown that abnormal methylation is an early key event in the pathogenesis of most human cancers, contributing to the development of tumors. However, little attention has been given to the potential of DNA methylation patterns as markers for Helicobacter pylori- (H. pylori-) associated gastric cancer (GC). In this study, an integrated analysis of DNA methylation and gene expression was conducted to identify some potential key epigenetic markers in H. pylori-associated GC. DNA methylation data of 28 H. pylori-positive and 168 H. pylori-negative GC samples were compared and analyzed. We also analyzed the gene expression data of 18 H. pylori-positive and 145 H. pylori-negative GC cases. Finally, the results were verified by in vitro and in vivo experiments. A total of 5609 differentially methylated regions associated with 2454 differentially methylated genes were identified. A total of 228 differentially expressed genes were identified from the gene expression data of H. pylori-positive and H. pylori-negative GC cases. The screened genes were analyzed for functional enrichment. Subsequently, we obtained 28 genes regulated by methylation through a Venn diagram, and we identified five genes (GSTO2, HUS1, INTS1, TMEM184A, and TMEM190) downregulated by hypermethylation. HUS1, GSTO2, and TMEM190 were expressed at lower levels in GC than in adjacent samples ( P < 0.05 ). Moreover, H. pylori infection decreased HUS1, GSTO2, and TMEM190 expression in vitro and in vivo. Our study identified HUS1, GSTO2, and TMEM190 as novel methylation markers for H. pylori-associated GC.

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