1
|
Zhang L, Yu F, Zhang Y, Li P. Implications of lncRNAs in Helicobacter pylori-associated gastrointestinal cancers: underlying mechanisms and future perspectives. Front Cell Infect Microbiol 2024; 14:1392129. [PMID: 39035354 PMCID: PMC11257847 DOI: 10.3389/fcimb.2024.1392129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Accepted: 06/19/2024] [Indexed: 07/23/2024] Open
Abstract
Helicobacter pylori (H. pylori) is a harmful bacterium that is difficult to conveniently diagnose and effectively eradicate. Chronic H. pylori infection increases the risk of gastrointestinal diseases, even cancers. Despite the known findings, more underlying mechanisms are to be deeply explored to facilitate the development of novel prevention and treatment strategies of H. pylori infection. Long noncoding RNAs (lncRNAs) are RNAs with more than 200 nucleotides. They may be implicated in cell proliferation, inflammation and many other signaling pathways of gastrointestinal cancer progression. The dynamic expression of lncRNAs indicates their potential to be diagnostic or prognostic biomarkers. In this paper, we comprehensively summarize the processes of H. pylori infection and the treatment methods, review the known findings of lncRNA classification and functional mechanisms, elucidate the roles of lncRNAs in H. pylori-related gastrointestinal cancer, and discuss the clinical perspectives of lncRNAs.
Collapse
Affiliation(s)
- Lei Zhang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, China
| | | | | | - Peifeng Li
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, China
| |
Collapse
|
2
|
Nguyen TMN, Tran VH, Ha TMT. Helicobacter pylori cagA, vacA, and iceA genotypes and clinical outcomes: a cross-sectional study in central Vietnam. Braz J Microbiol 2024; 55:1393-1404. [PMID: 38676790 PMCID: PMC11153385 DOI: 10.1007/s42770-024-01328-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Accepted: 04/01/2024] [Indexed: 04/29/2024] Open
Abstract
Helicobacter pylori is the most common cause of gastroduodenal diseases. The concept that cagA-positive H. pylori is a risk factor for gastric cancer appears to be true only for H. pylori strains from Western countries. Other virulent genes may have a synergistic interaction with cagA during pathogenesis. This study aims to investigate H. pylori cagA, vacA, and iceA prevalence, genotypes, and their association to clinical outcomes in Vietnamese patients. The cagA status and vacA and iceA genotypes were determined using the PCR technique on DNA extracted from gastric biopsies of 141 patients with gastroduodenal diseases. After performing molecular analysis for cagA, vacA, and iceA genes, samples with mixed H. pylori strains, positivity, or negativity for both cagA and cagPAI-empty site, or unidentified genotypes were excluded. Finally, 107 samples were examined. The presence of the cagA, vacA, and iceA genes were detected in 77.6%, 100%, and 80.4% of cases, respectively. Notably, cagA( +) with EPIYA-ABD, vacA s1i1m1, vacA s1i1m2, iceA1, and iceA2 accounted for 73.8%, 44.9%, 33.6%, 48.6%, and 31.8% of cases, respectively. Four iceA2 subtypes (24-aa, 59-aa, 94-aa, and 129-aa variants) were found, with the 59-aa variant the most prevalent (70.6%). The cagA( +)/vacAs1i1m1/iceA1 and cagA( +)/vacAs1i1m2/iceA1 combinations were found in 26.2% and 25.1% of cases, respectively. A multivariable logistic regression analysis was performed, after adjusting for age and gender, with the gastritis group was used as a reference control. Statistically significant associations were found between the vacA s1i1m2 genotype, the iceA1 variant, and the cagA( +)/vacAs1i1m2/iceA1 combination and gastric cancer; the adjusted ORs were estimated as 18.02 (95% CI: 3.39-95.81), 4.09 (95% CI: 1.1-15.08), and 16.19 (95% CI: 3.42-76.66), respectively. Interestingly, for the first time, our study found that vacA s1i1m2, but not vacA s1i1m1, was a risk factor for gastric cancer. This study illustrates the genetic diversity of the H. pylori cagA, vacA, and iceA genes across geographical regions and contributes to understanding the importance of these genotypes for clinical outcomes.
Collapse
Affiliation(s)
- Thi Mai Ngan Nguyen
- Department of Medical Genetics, University of Medicine and Pharmacy, Hue University, 6, Ngo Quyen Street, Hue City, 49100, Vietnam
| | - Van Huy Tran
- Department of Internal Medicine, University of Medicine and Pharmacy, Hue University, Hue City, Vietnam
- Centre of Gastroenterology and Endoscopy, University of Medicine and Pharmacy Hospital, Hue University, Hue City, Vietnam
| | - Thi Minh Thi Ha
- Department of Medical Genetics, University of Medicine and Pharmacy, Hue University, 6, Ngo Quyen Street, Hue City, 49100, Vietnam.
- Institute of Biomedicine, University of Medicine and Pharmacy, Hue University, Hue City, Vietnam.
| |
Collapse
|
3
|
Chaleshtori ZA, Rastegari AA, Nayeri H, Doosti A. Chitosan-LeoA-DNA Nanoparticles Promoted the Efficacy of Novel LeoA-DNA Vaccination on Mice Against Helicobacter pylori. Curr Microbiol 2024; 81:125. [PMID: 38558085 DOI: 10.1007/s00284-024-03642-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 02/18/2024] [Indexed: 04/04/2024]
Abstract
More than half of the world's population is infected with Helicobacter pylori (H. pylori), which may lead to chronic gastritis, peptic ulcers, and stomach cancer. LeoA, a conserved antigen of H. pylori, aids in preventing this infection by triggering specific CD3+ T-cell responses. In this study, recombinant plasmids containing the LeoA gene of H. pylori are created and conjugated with chitosan nanoparticle (CSNP) to immunize BALB/c mice against the H. pylori infection. We used the online Vaxign tool to analyze the genomes of five distinct strains of H. pylori, and we chose the outer membrane as a prospective vaccine candidate. Afterward, the proteins' immunogenicity was evaluated. The DNA vaccine was constructed and then encapsulated in CSNPs. The effectiveness of the vaccine's immunoprotective effects was evaluated in BALB/c mice. Purified activated splenic CD3+ T cells are used to test the anticancer effects in vitro. Nanovaccines had apparent spherical forms, were small (mean size, 150-250 nm), and positively charged (41.3 ± 3.11 mV). A consistently delayed release pattern and an entrapment efficiency (73.35 ± 3.48%) could be established. Compared to the non-encapsulated DNA vaccine, vaccinated BALB/c mice produced higher amounts of LeoA-specific IgG in plasma and TNF-α in splenocyte lysate. Moreover, BALB/c mice inoculated with nanovaccine demonstrated considerable immunity (87.5%) against the H. pylori challenge and reduced stomach injury and bacterial burdens in the stomach. The immunological state in individuals with GC with chronic infection with H. pylori is mimicked by the H. pylori DNA nanovaccines by inducing a shift from Th1 to Th2 in the response. In vitro human GC cell development is inhibited by activated CD3+ T lymphocytes. According to our findings, the H. pylori vaccine-activated CD3+ has potential immunotherapeutic benefits.
Collapse
Affiliation(s)
| | - Ali Asghar Rastegari
- Department of Molecular and Cell Biochemistry, Islamic Azad University, Falavarjan Branch, Isfahan, Iran.
| | - Hashem Nayeri
- Department of Biochemistry, Islamic Azad University, Falavarjan Branch, Isfahan, Iran
| | - Abbas Doosti
- Biotechnology Research Center, Islamic Azad University, Shahrekord Branch, Shahrekord, Iran
| |
Collapse
|
4
|
Marzhoseyni Z, Mousavi MJ, Ghotloo S. Helicobacter pylori antigens as immunomodulators of immune system. Helicobacter 2024; 29:e13058. [PMID: 38380545 DOI: 10.1111/hel.13058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 02/07/2024] [Accepted: 02/08/2024] [Indexed: 02/22/2024]
Abstract
Helicobacter pylori (H. pylori) is one of the most prevalent human pathogens and the leading cause of chronic infection in almost half of the population in the world (~59%). The bacterium is a major leading cause of chronic gastritis, gastric and duodenal ulcers, and two type of malignancies, gastric adenocarcinoma and mucosa-associated lymphoid tissue (MALT) lymphoma. Despite the immune responses mounted by the host, the bacteria are not cleared from the body resulting in a chronic infection accompanied by a chronic inflammation. Herein, a review of the literature discussing H. pylori antigens modulating the immune responses is presented. The mechanisms that are involved in the modulation of innate immune response, include modulation of recognition by pattern recognition receptors (PRRs) such as modulation of recognition by toll like receptors (TLR)4 and TLR5, modulation of phagocytic function, and modulation of phagocytic killing mediated by reactive oxygen species (ROS) and nitric oxide (NO). On the other hands, H. pylori modulates acquired immune response by the induction of tolerogenic dendritic cells (DCs), modulation of apoptosis, induction of regulatory T cells, modulation of T helper (Th)1 response, and modulation of Th17 response.
Collapse
Affiliation(s)
- Zeynab Marzhoseyni
- Department of Paramedicine, Amol School of Paramedical Sciences, Mazandaran University of Medical Sciences, Sari, Iran
| | - Mohammad Javad Mousavi
- Department of Hematology, Faculty of Allied Medicine, Bushehr University of Medical Sciences, Bushehr, Iran
| | - Somayeh Ghotloo
- Autoimmune Diseases Research Center, Kashan University of Medical Sciences, Kashan, Iran
- Department of Clinical Laboratory Sciences, School of Allied Medical Sciences, Kashan University of Medical Sciences, Kashan, Iran
| |
Collapse
|
5
|
Lee SH, Lim JM, Lee SW, Jang TH, Park JH, Seo YS, Lee JH, Seralathan KK, Oh BT. Effect of fermentation on antioxidant, antimicrobial, anti-inflammatory, and anti- Helicobacter pylori adhesion activity of Ulmus davidiana var. japonica root bark. Food Sci Biotechnol 2023; 32:1257-1268. [PMID: 37362805 PMCID: PMC10290026 DOI: 10.1007/s10068-023-01259-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 12/17/2022] [Accepted: 01/09/2023] [Indexed: 02/23/2023] Open
Abstract
The limited yield of Ulmus davidiana var. japonica root bark (URB) extract is considered an economic loss to the food industry. Improving extraction yield and bioactivity through fermentation increase the industrial usage of URB. The study aims to optimize the fermentation with cellulolytic and pectinolytic bacteria and evaluate the bioactivity and anti-Helicobacter pylori activity of the fermented URB extract. URB fermentation with the Bacillus licheniformis FLa3, isolated from salted seafood (Sardinella zunasi), under optimal conditions (37 °C, pH 6, 10% inoculum dose, and 36 h) improved the extraction yield by 36% compared to the control. The antioxidant and antimicrobial activity of the fermented extract were significantly higher than non-fermented extract. High-performance liquid chromatography results confirmed that the fermentation increased the proportion of bioactive components such as catechin (171.7%), epicatechin (144.3%), quercetin (27.3%), and kaempferol (16.7%). The results confirmed that the fermentation increased both the extraction yield and bioactivity.
Collapse
Affiliation(s)
- Seong-Hyeon Lee
- Division of Biotechnology, Advanced Institute of Environment and Bioscience, College of Environmental and Bioresource Sciences, Jeonbuk National University, Iksan, Jeonbuk 54596 South Korea
| | - Jeong-Muk Lim
- Division of Biotechnology, Advanced Institute of Environment and Bioscience, College of Environmental and Bioresource Sciences, Jeonbuk National University, Iksan, Jeonbuk 54596 South Korea
| | - Se-Won Lee
- Division of Biotechnology, Advanced Institute of Environment and Bioscience, College of Environmental and Bioresource Sciences, Jeonbuk National University, Iksan, Jeonbuk 54596 South Korea
| | - Tae-Hu Jang
- Division of Biotechnology, Advanced Institute of Environment and Bioscience, College of Environmental and Bioresource Sciences, Jeonbuk National University, Iksan, Jeonbuk 54596 South Korea
| | - Jung-Hee Park
- Division of Biotechnology, Advanced Institute of Environment and Bioscience, College of Environmental and Bioresource Sciences, Jeonbuk National University, Iksan, Jeonbuk 54596 South Korea
| | - Young-Seok Seo
- R&D Center, Sanigen CO., Ltd., Iksan, Jeonbuk 54576 South Korea
| | - Jeong-Ho Lee
- Sunchang Research Institute of Health and Longevity, Sunchang, Jeonbuk 56015 South Korea
| | - Kamala-Kannan Seralathan
- Division of Biotechnology, Advanced Institute of Environment and Bioscience, College of Environmental and Bioresource Sciences, Jeonbuk National University, Iksan, Jeonbuk 54596 South Korea
| | - Byung-Taek Oh
- Division of Biotechnology, Advanced Institute of Environment and Bioscience, College of Environmental and Bioresource Sciences, Jeonbuk National University, Iksan, Jeonbuk 54596 South Korea
| |
Collapse
|
6
|
Al-Sheboul SA, Mohammad AAR, Shboul Y, Brown B, Matalka II. A Genetic and Immunohistochemical Analysis of Helicobacter pylori Phenotypes and p27 Expression in Adenocarcinoma Patients in Jordan. J Epidemiol Glob Health 2023; 13:212-225. [PMID: 37071369 PMCID: PMC10272050 DOI: 10.1007/s44197-023-00099-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 04/04/2023] [Indexed: 04/19/2023] Open
Abstract
Stomach (gastric) cancer is one of the most prevalent and deadly cancers worldwide and most gastric cancers are adenocarcinomas. Based on prior research, there is an association between Helicobacter pylori (H. pylori) infection together with the frequency of duodenal ulcer, distal gastric adenocarcinoma, mucosa-associated lymphoid tissue (MALT) lymphoma, and antral gastritis. Helicobacter pylori virulence and toxicity factors have been identified before that significantly influence the clinical outcomes of H. pylori infection and gastric adenocarcinoma. However, it remains unclear exactly how different strains of H. pylori affect gastric adenocarcinoma. Current research suggests this involves tumor suppressor genes, like p27 but also H. pylori toxic virulence proteins. Therefore, we quantified known H. pylori genotypes within adenocarcinoma patients to establish the prevalence of known toxins that include cytotoxin-associated gene A (cagA) as well as vacuolating cytotoxin A (vacA) within patients of variable adenocarcinoma diagnosis. This analysis used gastrectomy samples validated for DNA viability. The incidence of H. pylori in adenocarcinoma patients in Jordan was established to be 54.5% positive (ureA gene positive) with cagA genotype occurrence at 57.1%, but also in this population study vacA gene ratios found to be 24.7%:22.1%:14.3%:14.3%. (vacAs1:vacAs2:vacAm1:vacAm2). Using immunohistochemistry (IHC), we confirmed with statistical significance that p27 was dysregulated and suppressed, within nearly all H. pylori vacA genotypes. In addition, within 24.6% of H. pylori samples analyzed was a different bacterial genotype, and curiously that p27 protein expression was retained in 12% of tested adenocarcinoma H. pylori samples. This is suggestive that p27 could be used as a prognostic indicator but also that an unknown genotype could be contributing to the regulatory effects of p27 protein within this bacterial and cellular environment that may include other virulence factors and unknown immune system regulatory changes.
Collapse
Affiliation(s)
- Suhaila A. Al-Sheboul
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, Jordan University of Science and Technology (JUST), Irbid, 22110 Jordan
| | - Ahmad Abdul-Razzak Mohammad
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, Jordan University of Science and Technology (JUST), Irbid, 22110 Jordan
| | - Yasemin Shboul
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, Jordan University of Science and Technology (JUST), Irbid, 22110 Jordan
| | | | - Ismail I. Matalka
- Department of Pathology and Microbiology, Faculty of Medicine, Jordan University of Science and Technology (JUST), Irbid, 22110 Jordan
| |
Collapse
|
7
|
Li XH, Xu JY, Wang X, Liao LJ, Huang L, Huang YQ, Zhang ZF. BanXiaXieXin decoction treating gastritis mice with drug-resistant Helicobacter pylori and its mechanism. World J Gastroenterol 2023; 29:2818-2835. [PMID: 37274067 PMCID: PMC10237109 DOI: 10.3748/wjg.v29.i18.2818] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 03/16/2023] [Accepted: 04/13/2023] [Indexed: 05/11/2023] Open
Abstract
BACKGROUND Helicobacter pylori (H. pylori) is the main pathogen that causes a variety of upper digestive diseases. The drug resistance rate of H. pylori is increasingly higher, and the eradication rate is increasingly lower. The antimicrobial resistance of H. pylori is an urgent global problem. It has been confirmed that Banxia Xiexin decoction (BXXXT) demonstrates the effects of treating gastrointestinal diseases, inhibiting H. pylori and protecting gastric mucosa. The purpose of the present study is to further explore the therapeutic effects of BXXXT on drug-resistant H. pylori.
AIM To confirm that BXXXT demonstrates therapeutical effects in vivo and in vitro on gastritis mice with drug-resistant H. pylori and explain its mechanism to provide an experimental basis for promoting the application of BXXXT.
METHODS The aqueous extract of BXXXT was gained by water decocting method. The inhibitory effect of the aqueous extract on H. pylori was detected by dilution in vitro; drug-resistant H. pylori cells were used to build an acute gastritis model in vivo. Thereafter, the model mice were treated with the aqueous extract of BXXXT. The amount of H. pylori colonization, the repair of gastric mucosal damage, changes of inflammatory factors, apoptosis, etc., were assessed. In terms of mechanism exploration, the main medicinal compositions of BXXXT aqueous extract and the synergistic bacteriostatic effects they had demonstrated were analyzed using mass spectrometry; the immune function of peripheral blood cells such as CD3+ T and CD4+ T of mice with gastritis before and after treatment with BXXXT aqueous extract was detected using a flow cytometry; the H. pylori transcriptome and proteome after treatment with BXXXT aqueous extract were detected. Differently expressed genes were screened and verification was performed thereon with knockout expression.
RESULTS The minimum inhibitory concentration of BXXXT aqueous extract against H. pylori was 256-512 μg/mL. A dose of 28 mg/kg BXXXT aqueous extract treatment produced better therapeutical effects than the standard triple therapy did; the BXXXT aqueous extract have at least 11 ingredients inhibiting H. pylori, including berberine, quercetin, baicalin, luteolin, gallic acid, rosmarinic acid, aloe emodin, etc., of which berberine, aloe emodin, luteolin and gallic acid have a synergistic effect; BXXXT aqueous extract was found to stimulate the expressions of CD3+ T and CD4+ T and increase the number of CD4+ T/CD8+ T in gastritis mice; the detection of transcriptome and proteome, quantitative polymerase chain reaction, Western blotting and knockout verification revealed that the main targets of BXXXT aqueous extract are CFAs related to urea enzymes, and CagA, VacA, etc.
CONCLUSION BXXXT aqueous extract could demonstrate good therapeutic effects on drug-resistance H. pylori in vitro and in vivo and its mechanism comes down to the synergistic or additional antibacterial effects of berberine, emodin and luteolin, the main components of the extract; the extract could activate the immune function and enhance bactericidal effects; BXXXT aqueous extract, with main targets of BXXXT aqueous extract related to urease, virulence factors, etc., could reduce the urease and virulence of H. pylori, weaken its colonization, and reduce its inflammatory damage to the gastric mucosa.
Collapse
Affiliation(s)
- Xiao-Hua Li
- Duate School, Guangxi Medical University, Nanning 5330021, Guangxi Zhuang Autonomous Region, China
| | - Jia-Yin Xu
- Guangxi Technology Innovation Cooperation Base of Prevention and Control Pathogenic Microbes with Drug Resistance, Youjiang Medical University for Nationalities, Baise 533000, Guangxi Zhuang Autonomous Region, China
| | - Xue Wang
- Guangxi Technology Innovation Cooperation Base of Prevention and Control Pathogenic Microbes with Drug Resistance, Youjiang Medical University for Nationalities, Baise 533000, Guangxi Zhuang Autonomous Region, China
| | - Li-Juan Liao
- Guangxi Technology Innovation Cooperation Base of Prevention and Control Pathogenic Microbes with Drug Resistance, Youjiang Medical University for Nationalities, Baise 533000, Guangxi Zhuang Autonomous Region, China
| | - Liang Huang
- Key Laboratory of the Prevention and Treatment of Drug Resistant Microbial Infecting, Youjiang Medical University for Nationalities, Baise 533000, Guangxi Zhuang Autonomous Region, China
| | - Yan-Qiang Huang
- Guangxi Technology Innovation Cooperation Base of Prevention and Control Pathogenic Microbes with Drug Resistance, Youjiang Medical University for Nationalities, Baise 533000, Guangxi Zhuang Autonomous Region, China
| | - Zeng-Feng Zhang
- Department of Microbiology, Guangxi Medical University, Nanning 530021, Guangxi Zhuang Autonomous Region, China
| |
Collapse
|
8
|
Innate immune activation and modulatory factors of Helicobacter pylori towards phagocytic and nonphagocytic cells. Curr Opin Immunol 2023; 82:102301. [PMID: 36933362 DOI: 10.1016/j.coi.2023.102301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 02/17/2023] [Indexed: 03/18/2023]
Abstract
Helicobacter pylori is an intriguing obligate host-associated human pathogen with a specific host interaction biology, which has been shaped by thousands of years of host-pathogen coevolution. Molecular mechanisms of interaction of H. pylori with the local immune cells in the human system are less well defined than epithelial cell interactions, although various myeloid cells, including neutrophils and other phagocytes, are locally present or attracted to the sites of infection and interact with H. pylori. We have recently addressed the question of novel bacterial innate immune stimuli, including bacterial cell envelope metabolites, that can activate and modulate cell responses via the H. pylori Cag type IV secretion system. This review article gives an overview of what is currently known about the interaction modes and mechanisms of H. pylori with diverse human cell types, with a focus on bacterial metabolites and cells of the myeloid lineage including phagocytic and antigen-presenting cells.
Collapse
|
9
|
The Remarkable Genetics of Helicobacter pylori. mBio 2022; 13:e0215822. [PMID: 36286549 PMCID: PMC9765472 DOI: 10.1128/mbio.02158-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Helicobacter pylori genome is more thoroughly mixed by homologous recombination than by any other organism that has been investigated, leading to apparent "free recombination" within populations. A recent mBio article by F. Ailloud, I. Estibariz, G. Pfaffinger, and S. Suerbaum (mBio 13:e01811-22, 2022, https://doi.org/10.1128/mbio.01811-22) helps to elucidate the cellular machinery that is used to achieve these unusual rates of genetic exchange. Specifically, they show that the UvrC gene, which is part of the repair machinery for DNA damage caused by ultraviolet light, has evolved an additional function in H. pylori, allowing very short tracts of DNA-with a mean length of only 28 bp-to be imported into the genome during natural transformation.
Collapse
|
10
|
Kato S, Gold BD, Kato A. Helicobacter pylori-Associated Iron Deficiency Anemia in Childhood and Adolescence-Pathogenesis and Clinical Management Strategy. J Clin Med 2022; 11:jcm11247351. [PMID: 36555966 PMCID: PMC9781328 DOI: 10.3390/jcm11247351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/07/2022] [Accepted: 12/08/2022] [Indexed: 12/14/2022] Open
Abstract
Many epidemiological studies and meta-analyses show that persistent Helicobacter pylori infection in the gastric mucosa can lead to iron deficiency or iron deficiency anemia (IDA), particularly in certain populations of children and adolescents. Moreover, it has been demonstrated that H. pylori infection can lead to and be closely associated with recurrent and/or refractory iron deficiency and IDA. However, the pathogenesis and specific risk factors leading to this clinical outcome in H. pylori-infected children remain poorly understood. In general, most of pediatric patients with H. pylori-associated IDA do not show evidence of overt blood loss due to gastrointestinal hemorrhagic lesions. In adult populations, H. pylori atrophic gastritis is reported to cause impaired iron absorption due to impaired gastric acid secretion, which, subsequently, results in IDA. However, significant gastric atrophy, and the resultant substantial reduction in gastric acid secretion, has not been shown in H. pylori-infected children. Recently, it has been hypothesized that competition between H. pylori and humans for iron availability in the upper gastrointestinal tract could lead to IDA. Many genes, including those encoding major outer membrane proteins (OMPs), are known to be involved in iron-uptake mechanisms in H. pylori. Recent studies have been published that describe H. pylori virulence factors, including specific OMP genes that may be associated with the pathogenesis of IDA. Daily iron demand substantively increases in children as they begin pubertal development starting with the associated growth spurt, and this important physiological mechanism may play a synergistic role for the microorganisms as a host pathogenetic factor of IDA. Like in the most recent pediatric guidelines, a test-and-treat strategy in H. pylori infection should be considered, especially for children and adolescents in whom IDA is recurrent or refractory to iron supplementation and other definitive causes have not been identified. This review will focus on providing the evidence that supports a clear biological plausibility for H. pylori infection and iron deficiency, as well as IDA.
Collapse
Affiliation(s)
- Seiichi Kato
- Kato Children’s Clinic, Natori 981-1227, Japan
- Correspondence: ; Tel.: +81-22-399-9152; Fax: +81-22-399-9153
| | - Benjamin D. Gold
- Gi Care for Kids, Children’s Center for Digestive Healthcare, LLC, Atlanta, GA 30342, USA
| | - Ayumu Kato
- Department of General Pediatrics and Gastroenterology, Miyagi Children’s Hospital, Sendai 989-3126, Japan
| |
Collapse
|
11
|
Freire de Melo F, Marques HS, Rocha Pinheiro SL, Lemos FFB, Silva Luz M, Nayara Teixeira K, Souza CL, Oliveira MV. Influence of Helicobacter pylori oncoprotein CagA in gastric cancer: A critical-reflective analysis. World J Clin Oncol 2022; 13:866-879. [PMID: 36483973 PMCID: PMC9724182 DOI: 10.5306/wjco.v13.i11.866] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 09/20/2022] [Accepted: 10/11/2022] [Indexed: 11/21/2022] Open
Abstract
Gastric cancer is the fifth most common malignancy and third leading cancer-related cause of death worldwide. Helicobacter pylori is a Gram-negative bacterium that inhabits the gastric environment of 60.3% of the world’s population and represents the main risk factor for the onset of gastric neoplasms. CagA is the most important virulence factor in H. pylori, and is a translocated oncoprotein that induces morphofunctional modifications in gastric epithelial cells and a chronic inflammatory response that increases the risk of developing precancerous lesions. Upon translocation and tyrosine phosphorylation, CagA moves to the cell membrane and acts as a pathological scaffold protein that simultaneously interacts with multiple intracellular signaling pathways, thereby disrupting cell proliferation, differentiation and apoptosis. All these alterations in cell biology increase the risk of damaged cells acquiring pro-oncogenic genetic changes. In this sense, once gastric cancer sets in, its perpetuation is independent of the presence of the oncoprotein, characterizing a “hit-and-run” carcinogenic mechanism. Therefore, this review aims to describe H. pylori- and CagA-related oncogenic mechanisms, to update readers and discuss the novelties and perspectives in this field.
Collapse
Affiliation(s)
- Fabrício Freire de Melo
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Brazil
| | - Hanna Santos Marques
- Campus Vitória da Conquista, Universidade Estadual do Sudoeste da Bahia, Vitória da Conquista 45029-094, Brazil
| | - Samuel Luca Rocha Pinheiro
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Brazil
| | - Fabian Fellipe Bueno Lemos
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Brazil
| | - Marcel Silva Luz
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Brazil
| | | | - Cláudio Lima Souza
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Brazil
| | | |
Collapse
|
12
|
Majewski M, Mertowska P, Mertowski S, Smolak K, Grywalska E, Torres K. Microbiota and the Immune System-Actors in the Gastric Cancer Story. Cancers (Basel) 2022; 14:cancers14153832. [PMID: 35954495 PMCID: PMC9367521 DOI: 10.3390/cancers14153832] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 08/04/2022] [Accepted: 08/06/2022] [Indexed: 11/16/2022] Open
Abstract
Simple Summary Stomach cancer is one of the most commonly diagnosed cancers in the world. Although the number of new cases is decreasing year by year, the death rate for this type of cancer is still high. The heterogeneous course and the lack of symptoms in the early stages of the disease mean that the diagnosis is made late, which translates into a worse prognosis for such patients. That is why it is so important to analyze potential risk factors that may increase the risk of developing gastric cancer and to search for new effective methods of treatment. These requirements are met by the analysis of the composition of the gastric microbiota and its relationship with the immune system, which is a key element in the human anti-cancer fight. This publication was created to systematize the current knowledge on the impact of dysbiosis of human microbiota on the development and progression of gastric cancer. Particular emphasis was placed on taking into account the role of the immune system in this process. Abstract Gastric cancer remains one of the most commonly diagnosed cancers in the world, with a relatively high mortality rate. Due to the heterogeneous course of the disease, its diagnosis and treatment are limited and difficult, and it is associated with a reduced prognosis for patients. That is why it is so important to understand the mechanisms underlying the development and progression of this cancer, with particular emphasis on the role of risk factors. According to the literature data, risk factors include: changes in the composition of the stomach and intestinal microbiota (microbiological dysbiosis and the participation of Helicobacter pylori), improper diet, environmental and genetic factors, and disorders of the body’s immune homeostasis. Therefore, the aim of this review is to systematize the knowledge on the influence of human microbiota dysbiosis on the development and progression of gastric cancer, with particular emphasis on the role of the immune system in this process.
Collapse
Affiliation(s)
- Marek Majewski
- 2nd Department of General, Gastrointestinal Surgery and Surgical Oncology of the Alimentary Tract, Medical University of Lublin, 20-081 Lublin, Poland
| | - Paulina Mertowska
- Department of Experimental Immunology, Medical University of Lublin, 20-093 Lublin, Poland
- Correspondence:
| | - Sebastian Mertowski
- Department of Experimental Immunology, Medical University of Lublin, 20-093 Lublin, Poland
| | - Konrad Smolak
- Department of Experimental Immunology, Medical University of Lublin, 20-093 Lublin, Poland
| | - Ewelina Grywalska
- Department of Experimental Immunology, Medical University of Lublin, 20-093 Lublin, Poland
| | - Kamil Torres
- Chair and Department of Didactics and Medical Simulation, Medical University of Lublin, 20-093 Lublin, Poland
| |
Collapse
|
13
|
Zhang J, Wang W, Yan S, Li J, Wei H, Zhao W. CagA and VacA inhibit gastric mucosal epithelial cell autophagy and promote the progression of gastric precancerous lesions. ZHONG NAN DA XUE XUE BAO. YI XUE BAN = JOURNAL OF CENTRAL SOUTH UNIVERSITY. MEDICAL SCIENCES 2022; 47:942-951. [PMID: 36039592 PMCID: PMC10930283 DOI: 10.11817/j.issn.1672-7347.2022.210779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Indexed: 06/15/2023]
Abstract
Cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA) are the keys to the pathogenic role of Helicobacter pylori and the high-risk factors for the progression of gastric precancerous lesions. Autophagy can stabilize the intracellular environment, resist Helicobacter pylori infection, prevent the accumulation of damaged DNA, and inhibit the proliferation of gastric precancerous variant cells. However, CagA and VacA can inhibit the activation of upstream signals of autophagy and the maturation of autophagy-lysosomes in various ways, thus inhibiting the autophagy of gastric mucosal cells in precancerous lesions of gastric cancer. This change can cause Helicobacter pylori to be unable to be effectively cleared by autophagy, so CagA and VacA can persist and promote the inflammation, oxidative stress, apoptosis of gastric mucosal tissue cells, and the glycolytic activity and proliferation of variant cells in gastric precancerous lesions and a series of malignant biological processes. In recent years, the research on drugs specifically inhibiting the activities of CagA and VacA has become a new direction for the prevention and treatment of Helicobacter pylori-related severe gastric diseases, and a variety of drugs or components that can precisely and effectively regulate the factors for the treatment of gastric precancerous lesions are emerged, which opens a new strategy for the treatment of gastric precancerous lesions in the future.
Collapse
Affiliation(s)
- Jiaxiang Zhang
- Basic Medical College, Shaanxi University of Traditional Chinese Medicine, Xianyang Shaanxi 712046.
| | - Wenba Wang
- Basic Medical College, Shaanxi University of Traditional Chinese Medicine, Xianyang Shaanxi 712046
| | - Shuguang Yan
- Basic Medical College, Shaanxi University of Traditional Chinese Medicine, Xianyang Shaanxi 712046.
| | - Jingtao Li
- Department of Hepatology, Affiliated Hospital of Shaanxi University of Traditional Chinese Medicine, Xianyang Shaanxi 712000
| | - Hailiang Wei
- Department of Hepatology, Affiliated Hospital of Shaanxi University of Traditional Chinese Medicine, Xianyang Shaanxi 712000
| | - Weihan Zhao
- Department of Gastroenterology, Affiliated Hospital of Shaanxi University of Traditional Chinese Medicine, Xianyang Shaanxi 712000, China
| |
Collapse
|
14
|
Biomarker Characterization and Prediction of Virulence and Antibiotic Resistance from Helicobacter pylori Next Generation Sequencing Data. Biomolecules 2022; 12:biom12050691. [PMID: 35625618 PMCID: PMC9138241 DOI: 10.3390/biom12050691] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 05/02/2022] [Accepted: 05/07/2022] [Indexed: 02/06/2023] Open
Abstract
The Gram-negative bacterium Helicobacter pylori colonizes c.a. 50% of human stomachs worldwide and is the major risk factor for gastric adenocarcinoma. Its high genetic variability makes it difficult to identify biomarkers of early stages of infection that can reliably predict its outcome. Moreover, the increasing antibiotic resistance found in H. pylori defies therapy, constituting a major human health problem. Here, we review H. pylori virulence factors and genes involved in antibiotic resistance, as well as the technologies currently used for their detection. Furthermore, we show that next generation sequencing may lead to faster characterization of virulence factors and prediction of the antibiotic resistance profile, thus contributing to personalized treatment and management of H. pylori-associated infections. With this new approach, more and permanent data will be generated at a lower cost, opening the future to new applications for H. pylori biomarker identification and antibiotic resistance prediction.
Collapse
|
15
|
Helicobacter pylori: an up-to-date overview on the virulence and pathogenesis mechanisms. Braz J Microbiol 2022; 53:33-50. [PMID: 34988937 PMCID: PMC8731681 DOI: 10.1007/s42770-021-00675-0] [Citation(s) in RCA: 64] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 12/24/2021] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori is an organism associated with ulcer disease and gastric cancer. The latter is one of the most prevalent malignancies and currently the fourth major cause of cancer-related deaths globally. The pathogen infects about 50% of the world population, and currently, no treatment ensures its total elimination. There has been an increase in our understanding of the pathophysiology and pathogenesis mechanisms of H. pylori over the years. H. pylori can induce several genetic alterations, express numerous virulence factors, and trigger diverse adaptive mechanisms during its adherence and colonization. For successful colonization and infection establishment, several effector proteins/toxins are released by the organism. Evidence is also available reporting spiral to coccoid transition as a unique tactic H. pylori uses to survive in the host’s gastrointestinal tract (GIT). Thus, the virulence and pathogenicity of H. pylori are under the control of complex interplay between the virulence factors, host, and environmental factors. Expounding the role of the various virulence factors in H. pylori pathogenesis and clinical outcomes is crucial for vaccine development and in providing and developing a more effective therapeutic intervention. Here we critically reflect on H. pylori infection and delineate what is currently known about the virulence and pathogenesis mechanisms of H. pylori.
Collapse
|
16
|
Functional Properties of Oligomeric and Monomeric Forms of Helicobacter pylori VacA Toxin. Infect Immun 2021; 89:e0034821. [PMID: 34543122 DOI: 10.1128/iai.00348-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Helicobacter pylori VacA is a secreted toxin that assembles into water-soluble oligomeric structures and forms anion-selective membrane channels. Acidification of purified VacA enhances its activity in cell culture assays. Sites of protomer-protomer contact within VacA oligomers have been identified by cryoelectron microscopy, and in the current study, we validated several of these interactions by chemical cross-linking and mass spectrometry. We then mutated amino acids at these contact sites and analyzed the effects of the alterations on VacA oligomerization and activity. VacA proteins with amino acid charge reversals at interprotomer contact sites retained the capacity to assemble into water-soluble oligomers and retained cell-vacuolating activity. Introduction of paired cysteine substitutions at these sites resulted in formation of disulfide bonds between adjacent protomers. Negative-stain electron microscopy and single-particle two-dimensional class analysis revealed that wild-type VacA oligomers disassemble when exposed to acidic pH, whereas the mutant proteins with paired cysteine substitutions retain an oligomeric state at acidic pH. Acid-activated wild-type VacA caused vacuolation of cultured cells, whereas acid-activated mutant proteins with paired cysteine substitutions lacked cell-vacuolating activity. Treatment of these mutant proteins with both low pH and a reducing agent resulted in VacA binding to cells, VacA internalization, and cell vacuolation. Internalization of a nonoligomerizing mutant form of VacA by host cells was detected without a requirement for acid activation. Collectively, these results enhance our understanding of the molecular interactions required for VacA oligomerization and support a model in which toxin activity depends on interactions of monomeric VacA with host cells.
Collapse
|
17
|
Carlosama-Rosero YH, Acosta-Astaiza CP, Sierra-Torres CH, Bolaños-Bravo HJ. Helicobacter pylori genotypes associated with gastric cancer and dysplasia in Colombian patients. REVISTA DE GASTROENTEROLOGÍA DE MÉXICO (ENGLISH EDITION) 2021; 87:181-187. [PMID: 34656500 DOI: 10.1016/j.rgmxen.2021.09.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 01/13/2021] [Indexed: 12/17/2022] Open
Abstract
INTRODUCTION AND AIMS Colombia has high incidence levels of gastric cancer that can be explained by the genetic variability of Helicobacter pylori (H. pylori). Our aim was to establish the relation of the H. pylori CagA and VacA genotypes to dysplasia and gastric cancer, in a high-risk population. MATERIAL AND METHODS A case-control study was conducted on 202 patients from a high-risk cancer zone. Patients with dysplasia and gastric cancer (cases) and patients with nonatrophic gastritis (controls) were included. Endoscopic sampling and histologic classification were carried out according to the Sydney system and the Lauren classification. Genetic information was obtained through polymerase chain reaction on paraffin blocks. The measures of association of the variables of interest were evaluated in bivariate and multivariate models. A P<0.05 was considered statistically significant and the SPSS version 25 program was employed. RESULTS Age above 50 years (OR: 23.76; CI: 8.40-67.17; P=0.000) and the VacA s1m1 genotype (OR: 6.18; CI: 1.25-30.51; P=0.025) were associated with higher risk for developing dysplasia and gastric cancer. The CagA+ genotype was not found to be a risk factor for developing those pathologies (OR: 1.02; CI: 0.39-2.62; P=0.965). CONCLUSIONS The H. pylori VacA genotypes are markers for the development of gastric cancer. That information could be used to create a risk index in a predictive model to optimize the healthcare of higher-risk patients.
Collapse
Affiliation(s)
- Y H Carlosama-Rosero
- Grupo Interdisciplinario de Investigación en Salud-Enfermedad, Universidad Cooperativa de Colombia, Pasto, Colombia.
| | - C P Acosta-Astaiza
- Grupo de Investigación en Genética Humana y Aplicada, Universidad del Cauca, Popayán, Colombia
| | - C H Sierra-Torres
- Grupo de Investigación en Genética Humana y Aplicada, Universidad del Cauca, Popayán, Colombia
| | - H J Bolaños-Bravo
- Grupo de Investigación en Genética Humana y Aplicada, Universidad del Cauca, Popayán, Colombia
| |
Collapse
|
18
|
Yuan LZ, Shi X, Tang D, Zheng SP, Xiao ZM, Wang F. Construction and preservation of a stable and highly expressed recombinant Helicobacter pylori vacuolating cytotoxin A with apoptotic activity. BMC Microbiol 2021; 21:229. [PMID: 34407768 PMCID: PMC8371779 DOI: 10.1186/s12866-021-02262-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 06/15/2021] [Indexed: 01/11/2023] Open
Abstract
Background H. pylori is closely related to the occurrence and development of various digestive gastritis, peptic ulcer and mucosa-associated lymphoid tissue (MALT) lymphoma. H. pylori is also a class I carcinogen of gastric cancer. VacA is the only exocrine toxin of H. pylori, which plays a very important role in the pathogenesis of H. pylori. The production of VacA in natural circumstances is complex with heavy workload and low yield. Therefore, it is very important to obtain recombinant VacA protein which is stable and biologically active. This study therefore aims to explore the expression, purification and stable storage of VacA toxin of H. pylori in E.coli, and to provide experimental basis for further exploration of the role of VacA in H. pylori -induced inflammation of cancer. Results A 2502-bp fragment and VacA gene were identified. An 89.7-kDa VacA34–854 recombinant protein was expressed and purified from the recombinant engineering bacteria and was preserved stably in 50 mM acetic acid buffer (pH 2.9). The amount of the recombinant protein was larger in the inclusion bodies than in the supernatant. In addition, after a 24-h culture with VacA recombinant protein, GES-1 cells demonstrated evidence of apoptosis including early nuclear immobilization and clustering under inverted microscope and TEM. It was found that VacA recombinant protein induced apoptosis by TUNEL assay. Conclusions A VacA recombinant protein that is stably and highly expressed and possesses pro-apoptotic activity is successfully constructed. The protein is stably preserved in 50 mM acetic acid buffer (pH 2.9). Supplementary Information The online version contains supplementary material available at 10.1186/s12866-021-02262-7.
Collapse
Affiliation(s)
- Ling-Zhi Yuan
- Department of Gastroenterology, the Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China.,Hunan Key Laboratory of Non-resolving Inflammation and Cancer, Central South University, Changsha, Hunan, 410013, China
| | - Xiao Shi
- Department of Gastroenterology, the Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China.,Hunan Key Laboratory of Non-resolving Inflammation and Cancer, Central South University, Changsha, Hunan, 410013, China
| | - Dan Tang
- Department of Gastroenterology, the Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China.,Hunan Key Laboratory of Non-resolving Inflammation and Cancer, Central South University, Changsha, Hunan, 410013, China
| | - Shao-Peng Zheng
- Department of Gastroenterology, the Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China.,Hunan Key Laboratory of Non-resolving Inflammation and Cancer, Central South University, Changsha, Hunan, 410013, China
| | - Zhi-Ming Xiao
- Department of Gastroenterology, the Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China.,Hunan Key Laboratory of Non-resolving Inflammation and Cancer, Central South University, Changsha, Hunan, 410013, China
| | - Fen Wang
- Department of Gastroenterology, the Third Xiangya Hospital, Central South University, Changsha, Hunan, 410013, China. .,Hunan Key Laboratory of Non-resolving Inflammation and Cancer, Central South University, Changsha, Hunan, 410013, China.
| |
Collapse
|
19
|
Rueda-Robles A, Rubio-Tomás T, Plaza-Diaz J, Álvarez-Mercado AI. Impact of Dietary Patterns on H. pylori Infection and the Modulation of Microbiota to Counteract Its Effect. A Narrative Review. Pathogens 2021; 10:875. [PMID: 34358024 PMCID: PMC8308520 DOI: 10.3390/pathogens10070875] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 07/07/2021] [Accepted: 07/09/2021] [Indexed: 12/12/2022] Open
Abstract
Helicobacter pylori (H. pylori) is a Gram-negative bacterium that colonizes the stomach and can induce gastric disease and intra-gastric lesions, including chronic gastritis, peptic ulcers, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. This bacterium is responsible for long-term complications of gastric disease. The conjunction of host genetics, immune response, bacterial virulence expression, diet, micronutrient availability, and microbiome structure influence the disease outcomes related to chronic H. pylori infection. In this regard, the consumption of unhealthy and unbalanced diets can induce microbial dysbiosis, which infection with H. pylori may contribute to. However, to date, clinical trials have reported controversial results and current knowledge in this field is inconclusive. Here, we review preclinical studies concerning the changes produced in the microbiota that may be related to H. pylori infection, as well as the involvement of diet. We summarize and discuss the last approaches based on the modulation of the microbiota to improve the negative impact of H. pylori infection and their potential translation from bench to bedside.
Collapse
Affiliation(s)
- Ascensión Rueda-Robles
- Center of Biomedical Research, Institute of Nutrition and Food Technology “José Mataix”, University of Granada, Avda. del Conocimiento s/n., Armilla, 18016 Granada, Spain;
| | - Teresa Rubio-Tomás
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain;
- School of Medicine, University of Crete, 70013 Heraklion, Crete, Greece
| | - Julio Plaza-Diaz
- Children’s Hospital Eastern Ontario Research Institute, Ottawa, ON K1H 8L1, Canada;
- Department of Biochemistry and Molecular Biology II, School of Pharmacy, University of Granada, 18071 Granada, Spain
- Instituto de Investigación Biosanitaria ibs.GRANADA, Complejo Hospitalario Universitario de Granada, 18014 Granada, Spain
| | - Ana I. Álvarez-Mercado
- Center of Biomedical Research, Institute of Nutrition and Food Technology “José Mataix”, University of Granada, Avda. del Conocimiento s/n., Armilla, 18016 Granada, Spain;
- Department of Biochemistry and Molecular Biology II, School of Pharmacy, University of Granada, 18071 Granada, Spain
- Instituto de Investigación Biosanitaria ibs.GRANADA, Complejo Hospitalario Universitario de Granada, 18014 Granada, Spain
| |
Collapse
|
20
|
Moghadam MT, Chegini Z, Norouzi A, Dousari AS, Shariati A. Three-Decade Failure to the Eradication of Refractory Helicobacter pylori Infection and Recent Efforts to Eradicate the Infection. Curr Pharm Biotechnol 2021; 22:945-959. [PMID: 32767919 DOI: 10.2174/1389201021666200807110849] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/30/2020] [Accepted: 07/04/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND Helicobacter pylori causes dangerous and deadly diseases such as gastric cancer and duodenal ulcers. Eradication and treatment of this bacterium are very important due to the deadly diseases caused by H. pylori and the high cost of treatment for countries. METHODS Thus, we present a complete list of the most important causes of failure in the treatment and eradication of H. pylori, and address new therapeutic methods that may be effective in controlling this bacterium in the future. RESULTS Many efforts have been made to control and eradicate this bacterium over the years, but no success has been achieved since its eradication is a complex process affected by the bacterial properties and host factors. Previous studies have shown that various factors are involved in the failure to eradicate H. pylori, such as new genotypes of the bacterium with higher pathogenicity, inappropriate patient cooperation, mutations, biofilm formation and dormant forms that cause antibiotic resistance, acidic stomach pH, high bacterial load, smoking, immunosuppressive features and intracellular occurrence of H. pylori. On the other hand, recent studies reported that the use of probiotics, nanoparticles, antimicrobial peptides, natural product and vaccines can be helpful in the treatment and eradication of H. pylori infections. CONCLUSION Eradication of H. pylori is crucial for the treatment of important diseases such as gastric cancer. Therefore, it seems that identifying the failure causes of treating this bacterium can be helpful in controlling the infections. Besides, further studies on new therapeutic strategies may help eradicate H. pylori in the future.
Collapse
Affiliation(s)
- Majid T Moghadam
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Zahra Chegini
- Student Research Committee, Iran University of Medical Sciences, Tehran, Iran
| | - Amin Norouzi
- Department of Microbiology and Virology, School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
| | | | - Aref Shariati
- Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| |
Collapse
|
21
|
Lopez Chiloeches M, Bergonzini A, Frisan T. Bacterial Toxins Are a Never-Ending Source of Surprises: From Natural Born Killers to Negotiators. Toxins (Basel) 2021; 13:426. [PMID: 34204481 PMCID: PMC8235270 DOI: 10.3390/toxins13060426] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 06/07/2021] [Accepted: 06/14/2021] [Indexed: 02/07/2023] Open
Abstract
The idea that bacterial toxins are not only killers but also execute more sophisticated roles during bacteria-host interactions by acting as negotiators has been highlighted in the past decades. Depending on the toxin, its cellular target and mode of action, the final regulatory outcome can be different. In this review, we have focused on two families of bacterial toxins: genotoxins and pore-forming toxins, which have different modes of action but share the ability to modulate the host's immune responses, independently of their capacity to directly kill immune cells. We have addressed their immuno-suppressive effects with the perspective that these may help bacteria to avoid clearance by the host's immune response and, concomitantly, limit detrimental immunopathology. These are optimal conditions for the establishment of a persistent infection, eventually promoting asymptomatic carriers. This immunomodulatory effect can be achieved with different strategies such as suppression of pro-inflammatory cytokines, re-polarization of the immune response from a pro-inflammatory to a tolerogenic state, and bacterial fitness modulation to favour tissue colonization while preventing bacteraemia. An imbalance in each of those effects can lead to disease due to either uncontrolled bacterial proliferation/invasion, immunopathology, or both.
Collapse
Affiliation(s)
| | | | - Teresa Frisan
- Department of Molecular Biology and Umeå Centre for Microbial Research (UCMR), Umeå University, 901 87 Umeå, Sweden; (M.L.C.); (A.B.)
| |
Collapse
|
22
|
González MF, Díaz P, Sandoval-Bórquez A, Herrera D, Quest AFG. Helicobacter pylori Outer Membrane Vesicles and Extracellular Vesicles from Helicobacter pylori-Infected Cells in Gastric Disease Development. Int J Mol Sci 2021; 22:ijms22094823. [PMID: 34062919 PMCID: PMC8124820 DOI: 10.3390/ijms22094823] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 03/31/2021] [Accepted: 04/02/2021] [Indexed: 02/08/2023] Open
Abstract
Extracellular vesicles (EVs) are cell-derived vesicles important in intercellular communication that play an essential role in host-pathogen interactions, spreading pathogen-derived as well as host-derived molecules during infection. Pathogens can induce changes in the composition of EVs derived from the infected cells and use them to manipulate their microenvironment and, for instance, modulate innate and adaptive inflammatory immune responses, both in a stimulatory or suppressive manner. Gastric cancer is one of the leading causes of cancer-related deaths worldwide and infection with Helicobacter pylori (H. pylori) is considered the main risk factor for developing this disease, which is characterized by a strong inflammatory component. EVs released by host cells infected with H. pylori contribute significantly to inflammation, and in doing so promote the development of disease. Additionally, H. pylori liberates vesicles, called outer membrane vesicles (H. pylori-OMVs), which contribute to atrophia and cell transformation in the gastric epithelium. In this review, the participation of both EVs from cells infected with H. pylori and H. pylori-OMVs associated with the development of gastric cancer will be discussed. By deciphering which functions of these external vesicles during H. pylori infection benefit the host or the pathogen, novel treatment strategies may become available to prevent disease.
Collapse
Affiliation(s)
- María Fernanda González
- Center for studies on Exercise, Metabolism and Cancer (CEMC), Laboratory of Cellular Communication, Program of Cell and Molecular Biology, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago 8380453, Chile; (M.F.G.); (P.D.); (A.S.-B.); (D.H.)
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile
| | - Paula Díaz
- Center for studies on Exercise, Metabolism and Cancer (CEMC), Laboratory of Cellular Communication, Program of Cell and Molecular Biology, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago 8380453, Chile; (M.F.G.); (P.D.); (A.S.-B.); (D.H.)
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile
| | - Alejandra Sandoval-Bórquez
- Center for studies on Exercise, Metabolism and Cancer (CEMC), Laboratory of Cellular Communication, Program of Cell and Molecular Biology, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago 8380453, Chile; (M.F.G.); (P.D.); (A.S.-B.); (D.H.)
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile
| | - Daniela Herrera
- Center for studies on Exercise, Metabolism and Cancer (CEMC), Laboratory of Cellular Communication, Program of Cell and Molecular Biology, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago 8380453, Chile; (M.F.G.); (P.D.); (A.S.-B.); (D.H.)
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile
| | - Andrew F. G. Quest
- Center for studies on Exercise, Metabolism and Cancer (CEMC), Laboratory of Cellular Communication, Program of Cell and Molecular Biology, Faculty of Medicine, Institute of Biomedical Sciences (ICBM), Universidad de Chile, Santiago 8380453, Chile; (M.F.G.); (P.D.); (A.S.-B.); (D.H.)
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile
- Corporación Centro de Estudios Científicos de las Enfermedades Crónicas (CECEC), Santiago 7680201, Chile
- Correspondence: ; Tel.: +56-2-29786832
| |
Collapse
|
23
|
Carlosama-Rosero YH, Acosta-Astaiza CP, Sierra-Torres CH, Bolaños-Bravo HJ. Helicobacter pylori genotypes associated with gastric cancer and dysplasia in Colombian patients. REVISTA DE GASTROENTEROLOGIA DE MEXICO (ENGLISH) 2021; 87:S0375-0906(21)00031-8. [PMID: 33789817 DOI: 10.1016/j.rgmx.2021.01.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 12/10/2020] [Accepted: 01/13/2021] [Indexed: 01/07/2023]
Abstract
INTRODUCTION AND AIMS Colombia has high incidence levels of gastric cancer that can be explained by the genetic variability of Helicobacter pylori (H. pylori). Our aim was to establish the relation of the H. pylori CagA and VacA genotypes to dysplasia and gastric cancer, in a high-risk population. MATERIAL AND METHODS A case-control study was conducted on 202 patients from a high-risk cancer zone. Patients with dysplasia and gastric cancer (cases) and patients with nonatrophic gastritis (controls) were included. Endoscopic sampling and histologic classification were carried out according to the Sydney system and the Lauren classification. Genetic information was obtained through polymerase chain reaction on paraffin blocks. The measures of association of the variables of interest were evaluated in bivariate and multivariate models. A P<0.05 was considered statistically significant and the SPSS version 25 program was employed. RESULTS Age above 50 years (OR: 23.76; CI: 8.40-67.17; P=0.000) and the VacA s1m1 genotype (OR: 6.18; CI: 1.25-30.51; P=0.025) were associated with higher risk for developing dysplasia and gastric cancer. The CagA+ genotype was not found to be a risk factor for developing those pathologies (OR: 1.02; CI: 0.39-2.62; P=0.965). CONCLUSIONS The H. pylori VacA genotypes are markers for the development of gastric cancer. That information could be used to create a risk index in a predictive model to optimize the healthcare of higher-risk patients.
Collapse
Affiliation(s)
- Y H Carlosama-Rosero
- Grupo Interdisciplinario de Investigación en Salud-Enfermedad, Universidad Cooperativa de Colombia, Pasto, Colombia.
| | - C P Acosta-Astaiza
- Grupo de Investigación en Genética Humana y Aplicada, Universidad del Cauca, Popayán, Colombia
| | - C H Sierra-Torres
- Grupo de Investigación en Genética Humana y Aplicada, Universidad del Cauca, Popayán, Colombia
| | - H J Bolaños-Bravo
- Grupo de Investigación en Genética Humana y Aplicada, Universidad del Cauca, Popayán, Colombia
| |
Collapse
|
24
|
Dey R, Rieger A, Banting G, Ashbolt NJ. Role of amoebae for survival and recovery of 'non-culturable' Helicobacter pylori cells in aquatic environments. FEMS Microbiol Ecol 2021; 96:5902844. [PMID: 32897313 PMCID: PMC7494403 DOI: 10.1093/femsec/fiaa182] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 09/02/2020] [Indexed: 12/12/2022] Open
Abstract
Helicobacter pylori is a fastidious Gram-negative bacterium that infects over half of the world's population, causing chronic gastritis and is a risk factor for stomach cancer. In developing and rural regions where prevalence rate exceeds 60%, persistence and waterborne transmission are often linked to poor sanitation conditions. Here we demonstrate that H. pylori not only survives but also replicates within acidified free-living amoebal phagosomes. Bacterial counts of the clinical isolate H. pylori G27 increased over 50-fold after three days in co-culture with amoebae. In contrast, a H. pylori mutant deficient in a cagPAI gene (cagE) showed little growth within amoebae, demonstrating the likely importance of a type IV secretion system in H. pylori for amoebal infection. We also demonstrate that H. pylori can be packaged by amoebae and released in extracellular vesicles. Furthermore, and for the first time, we successfully demonstrate the ability of two free-living amoebae to revert and recover viable but non-cultivable coccoid (VBNC)-H. pylori to a culturable state. Our studies provide evidence to support the hypothesis that amoebae and perhaps other free-living protozoa contribute to the replication and persistence of human-pathogenic H. pylori by providing a protected intracellular microenvironment for this pathogen to persist in natural aquatic environments and engineered water systems, thereby H. pylori potentially uses amoeba as a carrier and a vector of transmission.
Collapse
Affiliation(s)
- Rafik Dey
- School of Public Health, University of Alberta,11405-87 Avenue, Edmonton, Alberta T6G 1C9, Canada.,Deparment of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Aja Rieger
- Deparment of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Graham Banting
- School of Public Health, University of Alberta,11405-87 Avenue, Edmonton, Alberta T6G 1C9, Canada
| | - Nicholas J Ashbolt
- School of Public Health, University of Alberta,11405-87 Avenue, Edmonton, Alberta T6G 1C9, Canada.,Deparment of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta T6G 2E1, Canada.,Provincial Laboratory for Public Health (ProvLab), Alberta Health Services, Edmonton, Canada.,School of Environmental, Sciense and Engineering, Southern Cross University, Lismore NSW, Australia
| |
Collapse
|
25
|
Baj J, Forma A, Sitarz M, Portincasa P, Garruti G, Krasowska D, Maciejewski R. Helicobacter pylori Virulence Factors-Mechanisms of Bacterial Pathogenicity in the Gastric Microenvironment. Cells 2020; 10:E27. [PMID: 33375694 PMCID: PMC7824444 DOI: 10.3390/cells10010027] [Citation(s) in RCA: 145] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/18/2020] [Accepted: 12/22/2020] [Indexed: 12/11/2022] Open
Abstract
Gastric cancer constitutes one of the most prevalent malignancies in both sexes; it is currently the fourth major cause of cancer-related deaths worldwide. The pathogenesis of gastric cancer is associated with the interaction between genetic and environmental factors, among which infection by Helicobacter pylori (H. pylori) is of major importance. The invasion, survival, colonization, and stimulation of further inflammation within the gastric mucosa are possible due to several evasive mechanisms induced by the virulence factors that are expressed by the bacterium. The knowledge concerning the mechanisms of H. pylori pathogenicity is crucial to ameliorate eradication strategies preventing the possible induction of carcinogenesis. This review highlights the current state of knowledge and the most recent findings regarding H. pylori virulence factors and their relationship with gastric premalignant lesions and further carcinogenesis.
Collapse
Affiliation(s)
- Jacek Baj
- Department of Anatomy, Medical University of Lublin, 20-400 Lublin, Poland;
| | - Alicja Forma
- Chair and Department of Forensic Medicine, Medical University of Lublin, 20-090 Lublin, Poland;
| | - Monika Sitarz
- Department of Conservative Dentistry with Endodontics, Medical University of Lublin, 20-090 Lublin, Poland;
| | - Piero Portincasa
- Clinica Medica “Augusto Murri”, Department of Biomedical Sciences and Human Oncology, University of Bari “Aldo Moro”, 70124 Bari, Italy;
| | - Gabriella Garruti
- Section of Endocrinology, Department of Emergency and Organ Transplantations, University of Bari “Aldo Moro” Medical School, Piazza G. Cesare 11, 70124 Bari, Italy;
| | - Danuta Krasowska
- Department of Dermatology, Venerology and Paediatric Dermatology of Medical University of Lublin, 20-081 Lublin, Poland;
| | | |
Collapse
|
26
|
Algood HMS. T Cell Cytokines Impact Epithelial Cell Responses during Helicobacter pylori Infection. THE JOURNAL OF IMMUNOLOGY 2020; 204:1421-1428. [PMID: 32152211 DOI: 10.4049/jimmunol.1901307] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 12/08/2019] [Indexed: 12/24/2022]
Abstract
The goal of this Brief Review is to highlight literature that demonstrates how cytokines made by T lymphocytes impact the gastric epithelium, especially during Helicobacter pylori infection. These cytokines effect many of the diverse functions of the epithelium and the epithelium's interactions with H. pylori The focal point of this Brief Review will be on how T cell cytokines impact antimicrobial function and barrier function and how T cell cytokines influence the development and progression of cancer. Furthermore, the modulation of epithelial-derived chemokines by H. pylori infection will be discussed.
Collapse
Affiliation(s)
- Holly M Scott Algood
- Veterans Affairs Tennessee Valley Healthcare Services, Nashville, TN 37212; Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37212; and Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37212
| |
Collapse
|
27
|
Holland RL, Bosi KD, Harpring GH, Luo J, Wallig M, Phillips H, Blanke SR. Chronic in vivo exposure to Helicobacter pylori VacA: Assessing the efficacy of automated and long-term intragastric toxin infusion. Sci Rep 2020; 10:9307. [PMID: 32518315 PMCID: PMC7283276 DOI: 10.1038/s41598-020-65787-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 05/04/2020] [Indexed: 12/24/2022] Open
Abstract
Helicobacter pylori (Hp) secrete VacA, a diffusible pore-forming exotoxin that is epidemiologically linked to gastric disease in humans. In vitro studies indicate that VacA modulates gastric epithelial and immune cells, but the in vivo contributions of VacA as an important determinant of Hp colonization and chronic infection remain poorly understood. To identify perturbations in the stomachs of C57BL/6 or BALB/C mice that result specifically from extended VacA exposure, we evaluated the efficacy of administering purified toxin using automated infusion via surgically-implanted, intragastric catheters. At 3 and 30 days of interrupted infusion, VacA was detected in association with gastric glands. In contrast to previously-reported tissue damage resulting from short term exposure to Hp extracts administered by oral gavage, extended infusion of VacA did not damage stomach, esophageal, intestinal, or liver tissue. However, several alterations previously reported during Hp infection were detected in animals infused with VacA, including reduction of the gastric mucus layer, and increased vacuolation of parietal cells. VacA infusion invoked an immune response, as indicated by the detection of circulating VacA antibodies. These foundational studies support the use of VacA infusion for identifying gastric alterations that are unambiguously attributable to long-term exposure to toxin.
Collapse
Affiliation(s)
- Robin L Holland
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, USA
| | - Kristopher D Bosi
- Department of Microbiology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, USA
| | - Gregory H Harpring
- Department of Microbiology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, USA
| | - Jiayi Luo
- Department of Microbiology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, USA
| | - Matthew Wallig
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, USA
| | - Heidi Phillips
- Department of Veterinary Clinical Medicine, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, USA
| | - Steven R Blanke
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, USA. .,Department of Microbiology, School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, USA. .,Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, 61801, USA.
| |
Collapse
|
28
|
Functional Properties of Helicobacter pylori VacA Toxin m1 and m2 Variants. Infect Immun 2020; 88:IAI.00032-20. [PMID: 32284370 DOI: 10.1128/iai.00032-20] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 04/05/2020] [Indexed: 12/14/2022] Open
Abstract
Helicobacter pylori colonizes the gastric mucosa and secretes a pore-forming toxin (VacA). Two main types of VacA, m1 and m2, can be distinguished by phylogenetic analysis. Type m1 forms of VacA have been extensively studied, but there has been relatively little study of m2 forms. In this study, we generated H. pylori strains producing chimeric proteins in which VacA m1 segments of a parental strain were replaced by corresponding m2 sequences. In comparison to the parental m1 VacA protein, a chimeric protein (designated m2/m1) containing m2 sequences in the N-terminal portion of the m region was less potent in causing vacuolation of HeLa cells, AGS gastric cells, and AZ-521 duodenal cells and had reduced capacity to cause membrane depolarization or death of AZ-521 cells. Consistent with the observed differences in activity, the chimeric m2/m1 VacA protein bound to cells at reduced levels compared to the binding levels of the parental m1 protein. The presence of two strain-specific insertions or deletions within or adjacent to the m region did not influence toxin activity. Experiments with human gastric organoids grown as monolayers indicated that m1 and m2/m1 forms of VacA had similar cell-vacuolating activities. Interestingly, both forms of VacA bound preferentially to the basolateral surface of organoid monolayers and caused increased cell vacuolation when interacting with the basolateral surface compared to the apical surface. These data provide insights into functional correlates of sequence variation in the VacA midregion (m region).
Collapse
|
29
|
Papaefthymiou A, Doulberis M, Katsinelos P, Liatsos C, Polyzos SA, Kotronis G, Papanikolaou K, Kountouras J. Impact of nitric oxide's bidirectional role on glaucoma: focus onHelicobacter pylori–related nitrosative stress. Ann N Y Acad Sci 2020; 1465:10-28. [DOI: 10.1111/nyas.14253] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 09/07/2019] [Accepted: 09/17/2019] [Indexed: 12/12/2022]
Affiliation(s)
| | - Michael Doulberis
- Department of Gastroenterology and HepatologyUniversity of Zurich Zurich Switzerland
- Department of Internal Medicine, Second Medical Clinic, Ippokration HospitalAristotle University of Thessaloniki Thessaloniki Macedonia Greece
| | - Panagiotis Katsinelos
- Department of Internal Medicine, Second Medical Clinic, Ippokration HospitalAristotle University of Thessaloniki Thessaloniki Macedonia Greece
| | - Christos Liatsos
- Department of Gastroenterology401 General Military Hospital of Athens Athens Greece
| | - Stergios A. Polyzos
- Department of Internal Medicine, Second Medical Clinic, Ippokration HospitalAristotle University of Thessaloniki Thessaloniki Macedonia Greece
- First Department of Pharmacology, School of MedicineAristotle University of Thessaloniki Thessaloniki Macedonia Greece
| | - Georgios Kotronis
- Department of Internal MedicineAgios Pavlos General Hospital Thessaloniki Macedonia Greece
| | - Katerina Papanikolaou
- Department of Internal Medicine, Second Medical Clinic, Ippokration HospitalAristotle University of Thessaloniki Thessaloniki Macedonia Greece
| | - Jannis Kountouras
- Department of Internal Medicine, Second Medical Clinic, Ippokration HospitalAristotle University of Thessaloniki Thessaloniki Macedonia Greece
| |
Collapse
|
30
|
Seeger AY, Ringling MD, Zohair H, Blanke SR. Risk factors associated with gastric malignancy during chronic Helicobacter pylori Infection. MEDICAL RESEARCH ARCHIVES 2020; 8:2068. [PMID: 37655156 PMCID: PMC10470974 DOI: 10.18103/mra.v8i3.2068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
Chronic Helicobacter pylori (Hp) infection is considered to be the single most important risk factor for the development of gastric adenocarcinoma in humans, which is a leading cause of cancer-related death worldwide. Nonetheless, Hp infection does not always progress to malignancy, and, gastric adenocarcinoma can occur in the absence of detectable Hp carriage, highlighting the complex and multifactorial nature of gastric cancer. Here we review known contributors to gastric malignancy, including Hp virulence factors, host genetic variation, and multiple environmental variables. In addition, we assess emerging evidence that resident gastric microflora in humans might impact disease progression in Hp-infected individuals. Molecular approaches for microbe identification have revealed differences in the gastric microbiota composition between cancer and non-cancerous patients, as well as infected and uninfected individuals. Although the reasons underlying differences in microbial community structures are not entirely understood, gastric atrophy and hypochlorhydria that accompany chronic Hp infection may be a critical driver of gastric dysbiosis that promote colonization of microbes that contribute to increased risk of malignancy. Defining the importance and role of the gastric microbiota as a potential risk factor for Hp-associated gastric cancer is a vital and exciting area of current research.
Collapse
Affiliation(s)
- Ami Y. Seeger
- Department of Microbiology, School of Molecular and Cellular Biology, College of Liberal Arts and Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
| | - Megan D. Ringling
- Department of Microbiology, School of Molecular and Cellular Biology, College of Liberal Arts and Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
| | - Huzaifa Zohair
- Department of Microbiology, School of Molecular and Cellular Biology, College of Liberal Arts and Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
| | - Steven R. Blanke
- Department of Microbiology, School of Molecular and Cellular Biology, College of Liberal Arts and Sciences, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
- Biomedical and Translational Sciences Department, Carle Illinois College of Medicine, University of Illinois Urbana-Champaign, Urbana, Illinois, 61801
| |
Collapse
|
31
|
Immune Response in H. pylori-Associated Gastritis and Gastric Cancer. Gastroenterol Res Pract 2020; 2020:9342563. [PMID: 32411209 PMCID: PMC7204331 DOI: 10.1155/2020/9342563] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 11/28/2019] [Accepted: 12/04/2019] [Indexed: 12/12/2022] Open
Abstract
Helicobacter pylori (H. pylori) is the dominant member of the gastric microbiota and has infected more than half of the human population, of whom 5–15% develop gastric diseases ranging from gastritis and metaplasia to gastric cancer. These diseases always follow inflammation induced by cell surface and intracellular receptors and subsequent signaling, such as the NF-κB pathway and inflammasomes. Some types of immune cells are recruited to enforce an antibacterial response, which could be impeded by H. pylori virulence factors with or without a specific immune cell. Following decreased inflammation, neoplasm may appear with a little immune surveillance and may inhibit antitumor immunity. Therefore, the balance between H. pylori-associated inflammation and anti-inflammation is crucial for human health and remains to be determined. Here, we discuss multiple inflammation and immunoregulatory cells in gastritis and summarize the main immune evasion strategies employed by gastric cancer.
Collapse
|
32
|
Activity and Functional Importance of Helicobacter pylori Virulence Factors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1149:35-56. [PMID: 31016624 DOI: 10.1007/5584_2019_358] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Helicobacter pylori is a very successful Gram-negative pathogen colonizing the stomach of humans worldwide. Infections with this bacterium can generate pathologies ranging from chronic gastritis and peptic ulceration to gastric cancer. The best characterized H. pylori virulence factors that cause direct cell damage include an effector protein encoded by the cytotoxin-associated gene A (CagA), a type IV secretion system (T4SS) encoded in the cag-pathogenicity island (cag PAI), vacuolating cytotoxin A (VacA), γ-glutamyl transpeptidase (GGT), high temperature requirement A (HtrA, a serine protease) and cholesterol glycosyl-transferase (CGT). Since these H. pylori factors are either surface-exposed, secreted or translocated, they can directly interact with host cell molecules and are able to hijack cellular functions. Studies on these bacterial factors have progressed substantially in recent years. Here, we review the current status in the characterization of signaling cascades by these factors in vivo and in vitro, which comprise the disruption of cell-to-cell junctions, induction of membrane rearrangements, cytoskeletal dynamics, proliferative, pro-inflammatory, as well as, pro-apoptotic and anti-apoptotic responses or immune evasion. The impact of these signal transduction modules in the pathogenesis of H. pylori infections is discussed.
Collapse
|
33
|
de Brito BB, da Silva FAF, Soares AS, Pereira VA, Santos MLC, Sampaio MM, Neves PHM, de Melo FF. Pathogenesis and clinical management of Helicobacter pylori gastric infection. World J Gastroenterol 2019; 25:5578-5589. [PMID: 31602159 PMCID: PMC6785516 DOI: 10.3748/wjg.v25.i37.5578] [Citation(s) in RCA: 133] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Revised: 08/14/2019] [Accepted: 08/19/2019] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori (H. pylori) is a gram-negative bacterium that infects approximately 4.4 billion individuals worldwide. However, its prevalence varies among different geographic areas, and is influenced by several factors. The infection can be acquired by means of oral-oral or fecal-oral transmission, and the pathogen possesses various mechanisms that improve its capacity of mobility, adherence and manipulation of the gastric microenvironment, making possible the colonization of an organ with a highly acidic lumen. In addition, H. pylori presents a large variety of virulence factors that improve its pathogenicity, of which we highlight cytotoxin associated antigen A, vacuolating cytotoxin, duodenal ulcer promoting gene A protein, outer inflammatory protein and gamma-glutamyl transpeptidase. The host immune system, mainly by means of a Th1-polarized response, also plays a crucial role in the infection course. Although most H. pylori-positive individuals remain asymptomatic, the infection predisposes the development of various clinical conditions as peptic ulcers, gastric adenocarcinomas and mucosa-associated lymphoid tissue lymphomas. Invasive and non-invasive diagnostic methods, each of them with their related advantages and limitations, have been applied in H. pylori detection. Moreover, bacterial resistance to antimicrobial therapy is a major challenge in the treatment of this infection, and new therapy alternatives are being tested to improve H. pylori eradication. Last but not least, the development of effective vaccines against H. pylori infection have been the aim of several research studies.
Collapse
Affiliation(s)
- Breno Bittencourt de Brito
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Bahia, Brazil
| | | | - Aline Silva Soares
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Bahia, Brazil
| | - Vinícius Afonso Pereira
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Bahia, Brazil
| | - Maria Luísa Cordeiro Santos
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Bahia, Brazil
| | - Mariana Miranda Sampaio
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Bahia, Brazil
| | - Pedro Henrique Moreira Neves
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Bahia, Brazil
| | - Fabrício Freire de Melo
- Instituto Multidisciplinar em Saúde, Universidade Federal da Bahia, Vitória da Conquista 45029-094, Bahia, Brazil
| |
Collapse
|
34
|
Marinoni C, Ribaldone DG, Rosso C, Astegiano M, Caviglia GP. Diagnosis of Helicobacter pylori infection: a look into molecular aspects of urea breath test. MINERVA BIOTECNOL 2019. [DOI: 10.23736/s1120-4826.19.02555-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
35
|
Gupta N, Maurya S, Verma H, Verma VK. Unraveling the factors and mechanism involved in persistence: Host-pathogen interactions in Helicobacter pylori. J Cell Biochem 2019; 120:18572-18587. [PMID: 31237031 DOI: 10.1002/jcb.29201] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Accepted: 05/20/2019] [Indexed: 12/15/2022]
Abstract
Helicobacter pylori and humans have one of the most complex relationships in nature. How a bacterium manages to live in one of the harshest and hostile environments is a topic of unraveling mysteries. H. pylori is a prevalent species and it colonizes the human gut of more than 50% of the world population. It infects the epithelial region of antrum and persists there for a long period. Over the time of evolution, H. pylori has developed complex strategies to extend the degree of inflammation in gastric mucosa. H. pylori needs specific adaptations for initial colonization into the host environment like helical shape, flagellar movement, chemotaxis, and the production of urease enzyme that neutralizes acidic environment of the stomach. There are several factors from the bacterium as well as from the host that participate in these complex interactions. On the other hand, to establish the persistent infection, H. pylori escapes the immune system by mimicking the host antigens. This pathogen has the ability to dodge the immune system and then persist there in the form of host cell, which leads to immune tolerance. H. pylori has an ability to manipulate its own pathogen-associated molecular patterns, which leads to an inhibition in the binding with specific pattern recognition receptors of the host to avoid immune cell detection. Also, it manipulates the host metabolic homeostasis in the gastric epithelium. Besides, it has several genes, which may get involved in the acquisition of nutrition from the host to survive longer in the host. Due to the persistence of H. pylori, it causes chronic inflammation and raises the chances of gastric cancer. This review highlights the important elements, which are certainly responsible for the persistence of H. pylori in the human host.
Collapse
Affiliation(s)
- Nidhi Gupta
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Kishangarh, India
| | - Shweta Maurya
- Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Kishangarh, India
| | - Harshvardhan Verma
- Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Kishangarh, India
| | - Vijay K Verma
- Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Kishangarh, India
| |
Collapse
|
36
|
Chauhan N, Tay ACY, Marshall BJ, Jain U. Helicobacter pylori VacA, a distinct toxin exerts diverse functionalities in numerous cells: An overview. Helicobacter 2019; 24:e12544. [PMID: 30324717 DOI: 10.1111/hel.12544] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 08/21/2018] [Accepted: 09/06/2018] [Indexed: 02/06/2023]
Abstract
BACKGROUND Helicobacter pylori, gastric cancer-causing bacteria, survive in their gastric environment of more than 50% of the world population. The presence of H. pylori in the gastric vicinity promotes the development of various diseases including peptic ulcer and gastric carcinoma. H. pylori produce and secret Vacuolating cytotoxin A (VacA), a major toxin facilitating the bacteria against the host defense system. The toxin causes multiple effects in epithelial cells and immune cells, especially T cells, B cells, and Macrophages. METHODS This review describes the diverse functionalities of protein toxin VacA. The specific objective of this review is to address the overall structure, mechanism, and functions of VacA in various cell types. The recent advancements are summarized and discussed and thus conclusion is drawn based on the overall reported evidences. RESULTS The searched articles on H. pylori VacA were evaluated and limited up to 66 articles for this review. The articles were divided into four major categories including articles on vacA gene, VacA toxin, distinct effects of VacA toxin, and their effects on various cells. Based on these studies, the review article was prepared. CONCLUSIONS This review describes an overview of how VacA is secreted by H. pylori and contributes to colonization and virulence in multiple ways by affecting epithelial cells, T cells, Dendritic cells, B cells, and Macrophages. The reported evidence suggests that the comprehensive outlook need to be developed for understanding distinctive functionalities of VacA.
Collapse
Affiliation(s)
- Nidhi Chauhan
- Amity Institute of Nanotechnology, Amity University, Noida, Uttar Pradesh, India
| | - Alfred Chin Yen Tay
- The Marshall Centre for Infectious Diseases Research and Training, The University of Western Australia, Nedlands, Western Australia, Australia.,Shenzhen Dapeng New District Kuichong People Hospital, Shenzhen, Guangdong, China
| | - Barry J Marshall
- The Marshall Centre for Infectious Diseases Research and Training, The University of Western Australia, Nedlands, Western Australia, Australia
| | - Utkarsh Jain
- Amity Institute of Nanotechnology, Amity University, Noida, Uttar Pradesh, India
| |
Collapse
|
37
|
García-Gil A, Lopez-Bailon LU, Ortiz-Navarrete V. Beyond the antibody: B cells as a target for bacterial infection. J Leukoc Biol 2019; 105:905-913. [PMID: 30657607 DOI: 10.1002/jlb.mr0618-225r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 12/15/2018] [Accepted: 12/26/2018] [Indexed: 12/16/2022] Open
Abstract
It is well established that B cells play an important role during infections beyond antibody production. B cells produce cytokines and are APCs for T cells. Recently, it has become clear that several pathogenic bacterial genera, such as Salmonella, Brucella, Mycobacterium, Listeria, Francisella, Moraxella, and Helicobacter, have evolved mechanisms such as micropinocytosis induction, inflammasome down-regulation, inhibitory molecule expression, apoptosis induction, and anti-inflammatory cytokine secretion to manipulate B cell functions influencing immune responses. In this review, we summarize our current understanding of B cells as targets of bacterial infection and the mechanisms by which B cells become a niche for bacterial survival and replication away from extracellular immune responses such as complement and antibodies.
Collapse
Affiliation(s)
- Abraham García-Gil
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Luis Uriel Lopez-Bailon
- Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Vianney Ortiz-Navarrete
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| |
Collapse
|
38
|
Influence of Helicobacter pylori virulence factors CagA and VacA on pathogenesis of gastrointestinal disorders. Microb Pathog 2018; 117:43-48. [PMID: 29432909 DOI: 10.1016/j.micpath.2018.02.016] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 01/07/2018] [Accepted: 02/08/2018] [Indexed: 12/23/2022]
Abstract
Helicobacter Pylori (H. pylori) is a gram-negative bacteria infecting numerous people all over the world. It has been established that H. pylori play an important role in pathogenesis of gastritis, peptic ulcer and gastric cancer. Pathogenic features of this bacterium are mainly attributes to the existence of pathogenic islands (PAI) genes. The most known genes in these islands are cytotoxin-associated gene A (CagA) and vacuolating cytotoxin gene (VacA). Most studies demonstrated various frequency of CagA and VacA in patient with peptic ulcer or gastritis in different countries. This variation in CagA and VacA frequency may be due to the capability of this bacterium to be genetically versatile and can alter the expression of these genes with geographic diversity. Although H. pylori infection is not usually associated with any clinical symptoms, but sometimes leads to inflammation in gastrointestinal system and resulted in peptic ulcer and gastric cancer. In this regard, this review will illustrate the importance of Helicobacter pylori in pathogenesis of gastrointestinal disorders with focusing on CagA and VacA virulence factors.
Collapse
|
39
|
Necchi V, Sommi P, Vanoli A, Fiocca R, Ricci V, Solcia E. Natural history of Helicobacter pylori VacA toxin in human gastric epithelium in vivo: vacuoles and beyond. Sci Rep 2017; 7:14526. [PMID: 29109534 PMCID: PMC5673961 DOI: 10.1038/s41598-017-15204-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 10/23/2017] [Indexed: 02/08/2023] Open
Abstract
Uptake, intracellular trafficking and pathologic effects of VacA toxin from Helicobacter pylori have been widely investigated in vitro. However, no systematic analysis investigated VacA intracellular distribution and fate in H. pylori-infected human gastric epithelium in vivo, using ultrastructural immunocytochemistry that combines precise toxin localization with analysis of the overall cell ultrastructure and intercompartimental/interorganellar relationships. By immunogold procedure, in this study we investigated gastric biopsies taken from dyspeptic patients to characterize the overall toxin’s journey inside human gastric epithelial cells in vivo. Endocytic pits were found to take up VacA at sites of bacterial adhesion, leading to a population of peripheral endosomes, which in deeper (juxtanuclear) cytoplasm enlarged and fused each other to form large VacA-containing vacuoles (VCVs). These directly opened into endoplasmic reticulum (ER) cisternae, which in turn enveloped mitochondria and contacted the Golgi apparatus. In all such organelles we found toxin molecules, often coupled with structural damage. These findings suggest direct toxin transfer from VCVs to other target organelles such as ER/Golgi and mitochondria. VacA-induced cytotoxic changes were associated with the appearance of auto(phago)lysosomes containing VacA, polyubiquitinated proteins, p62/SQSTM1 protein, cathepsin D, damaged mitochondria and bacterial remnants, thus leading to persistent cell accumulation of degradative products.
Collapse
Affiliation(s)
- Vittorio Necchi
- Department of Molecular Medicine, Pathologic Anatomy and Human Physiology Units, University of Pavia, Pavia, Italy.,Centro Grandi Strumenti, University of Pavia, Pavia, Italy
| | - Patrizia Sommi
- Department of Molecular Medicine, Pathologic Anatomy and Human Physiology Units, University of Pavia, Pavia, Italy
| | - Alessandro Vanoli
- Department of Molecular Medicine, Pathologic Anatomy and Human Physiology Units, University of Pavia, Pavia, Italy
| | - Roberto Fiocca
- Department of Surgical and Diagnostic Sciences, Pathology Unit, University of Genova and IRCCS S. Martino, Genova, Italy
| | - Vittorio Ricci
- Department of Molecular Medicine, Pathologic Anatomy and Human Physiology Units, University of Pavia, Pavia, Italy.
| | - Enrico Solcia
- Department of Molecular Medicine, Pathologic Anatomy and Human Physiology Units, University of Pavia, Pavia, Italy.,Pathologic Anatomy Service, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| |
Collapse
|
40
|
McClain MS, Beckett AC, Cover TL. Helicobacter pylori Vacuolating Toxin and Gastric Cancer. Toxins (Basel) 2017; 9:toxins9100316. [PMID: 29023421 PMCID: PMC5666363 DOI: 10.3390/toxins9100316] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 10/03/2017] [Accepted: 10/05/2017] [Indexed: 12/13/2022] Open
Abstract
Helicobacter pylori VacA is a channel-forming toxin unrelated to other known bacterial toxins. Most H. pylori strains contain a vacA gene, but there is marked variation among strains in VacA toxin activity. This variation is attributable to strain-specific variations in VacA amino acid sequences, as well as variations in the levels of VacA transcription and secretion. In this review, we discuss epidemiologic studies showing an association between specific vacA allelic types and gastric cancer, as well as studies that have used animal models to investigate VacA activities relevant to gastric cancer. We also discuss the mechanisms by which VacA-induced cellular alterations may contribute to the pathogenesis of gastric cancer.
Collapse
Affiliation(s)
- Mark S McClain
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Amber C Beckett
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
| | - Timothy L Cover
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN 37212, USA.
| |
Collapse
|
41
|
Abadi ATB. Strategies used by helicobacter pylori to establish persistent infection. World J Gastroenterol 2017; 23:2870-2882. [PMID: 28522905 PMCID: PMC5413782 DOI: 10.3748/wjg.v23.i16.2870] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 02/01/2017] [Accepted: 02/17/2017] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori (H. pylori) is a Gram-negative and motile bacterium that colonizes the hostile microniche of the human stomach, then persists for the host’s entire life, if not effectively treated. Clinically, H. pylori plays a causative role in the development of a wide spectrum of diseases including chronic active gastritis, peptic ulceration, gastric adenocarcinoma, and gastric mucosa-associated lymphoid tissue lymphoma. Due to the global distribution of H. pylori, it is no exaggeration to conclude that smart strategies are contributing to adaptation of the bacterium to its permanent host. Thirty-four years after the discovery of this bacterium, there are still many unanswered questions. For example, which strategies help the bacterium to survive in this inhospitable microniche? This question is slightly easier to answer if we presume the same clinical concept for both persistent infection and disease. Understanding the mechanisms governing H. pylori persistence will improve identification of the increased risk of diseases such as gastric cancer in patients infected with this bacterium. A well-defined and long-term equilibrium between the human host and H. pylori allows bacterial persistence in the gastric microniche; although this coexistence leads to a high risk of severe diseases such as gastric cancer. To escape the bactericidal activity of stomach acid, H. pylori secretes large amounts of surface-associated and cytosolic urease. The potential to avoid acidic conditions and immune evasion are discussed in order to explain the persistence of H. pylori colonization in the gastric mucosa, and data on bacterial genetic diversity are included. Information on the mechanisms related to H. pylori persistence can also provide the direction for future research concerning effective therapy and management of gastroduodenal disorders. The topics presented in the current review are important for elucidating the strategies used by H. pylori to help the bacterium persist in relation to the immune system and the many unfavorable features of living in the gastric microniche.
Collapse
|