Phylogeographic Origin of Helicobacter pylori Determines Host-Adaptive Responses upon Coculture with Gastric Epithelial Cells

ABSTRACTWhileHelicobacter pyloriinfects over 50% of the world's population, the mechanisms involved in the development of gastric disease are not fully understood. Bacterial, host, and environmental factors play a role in disease outcome. To investigate the role of bacterial factors inH. pyloripathogenesis, global gene expression of sixH. pyloriisolates was analyzed during coculture with gastric epithelial cells. Clustering analysis of six Colombian clinical isolates from a region with low gastric cancer risk and a region with high gastric cancer risk segregated strains based on their phylogeographic origin. One hundred forty-six genes had increased expression in European strains, while 350 genes had increased expression in African strains. Differential expression was observed in genes associated with motility, pathogenicity, and other adaptations to the host environment. European strains had greater expression of the virulence factorscagA,vacA, andbabBand were associated with increased gastric histologic lesions in patients. In AGS cells, European strains promoted significantly higher interleukin-8 (IL-8) expression than did African strains. African strains significantly induced apoptosis, whereas only one European strain significantly induced apoptosis. Our data suggest that gene expression profiles of clinical isolates can discriminate strains by phylogeographic origin and that these profiles are associated with changes in expression of the proinflammatory and protumorigenic cytokine IL-8 and levels of apoptosis in host epithelial cells. These findings support the hypothesis that bacterial factors determined by the phylogeographic origin ofH. pyloristrains may promote increased gastric disease.

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Inhibitory Effect of β-Carotene on Helicobacter pylori-Induced TRAF Expression and Hyper-Proliferation in Gastric Epithelial Cells

Antioxidants ◽

10.3390/antiox8120637 ◽

2019 ◽

Vol 8 (12) ◽

pp. 637 ◽

Cited By ~ 2

Author(s):

Yongchae Park ◽

Hanbit Lee ◽

Joo Weon Lim ◽

Hyeyoung Kim

Keyword(s):

Gene Expression ◽

Gastric Cancer ◽

Helicobacter Pylori ◽

Epithelial Cells ◽

Nadph Oxidase ◽

Gastric Epithelial Cells ◽

Gastric Cancer Cells ◽

Ags Cells ◽

H Pylori ◽

Β Carotene

Helicobacter pylori infection causes the hyper-proliferation of gastric epithelial cells that leads to the development of gastric cancer. Overexpression of tumor necrosis factor receptor associated factor (TRAF) is shown in gastric cancer cells. The dietary antioxidant β-carotene has been shown to counter hyper-proliferation in H. pylori-infected gastric epithelial cells. The present study was carried out to examine the β-carotene mechanism of action. We first showed that H. pylori infection decreases cellular IκBα levels while increasing cell viability, NADPH oxidase activity, reactive oxygen species production, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation, and TRAF1 and TRAF2 gene expression, as well as protein–protein interaction in gastric epithelial AGS cells. We then demonstrated that pretreatment of cells with β-carotene significantly attenuates these effects. Our findings support the proposal that β-carotene has anti-cancer activity by reducing NADPH oxidase-mediated production of ROS, NF-κB activation and NF-κB-regulated TRAF1 and TRAF2 gene expression, and hyper-proliferation in AGS cells. We suggest that the consumption of β-carotene-enriched foods could decrease the incidence of H. pylori-associated gastric disorders.

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Helicobacter pylori and Epstein-Barr Virus Coinfection Stimulates Aggressiveness in Gastric Cancer through the Regulation of Gankyrin

mSphere ◽

10.1128/msphere.00751-21 ◽

2021 ◽

Author(s):

Dharmendra Kashyap ◽

Budhadev Baral ◽

Shweta Jakhmola ◽

Anil Kumar Singh ◽

Hem Chandra Jha

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Epithelial Cells ◽

Epstein Barr Virus ◽

Synergistic Effects ◽

Gastric Epithelial Cells ◽

Content Type ◽

Barr Virus ◽

Epstein Barr ◽

H Pylori

In the present study, we evaluated the synergistic effects of EBV and H. pylori infection on gastric epithelial cells in various coinfection models. These coinfection models were among the first to depict the exposures of gastric epithelial cells to EBV followed by H. pylori ; however, coinfection models exist that narrated the scenario upon exposure to H. pylori followed by that to EBV.

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Helicobacter pylori VacA Induces Programmed Necrosis in Gastric Epithelial Cells

Infection and Immunity ◽

10.1128/iai.01370-10 ◽

2011 ◽

Vol 79 (7) ◽

pp. 2535-2543 ◽

Cited By ~ 72

Author(s):

Jana N. Radin ◽

Christian González-Rivera ◽

Susan E. Ivie ◽

Mark S. McClain ◽

Timothy L. Cover

Keyword(s):

Gastric Cancer ◽

Cell Death ◽

Helicobacter Pylori ◽

Epithelial Cells ◽

Human Stomach ◽

Gastric Epithelial Cells ◽

Wild Type ◽

Programmed Necrosis ◽

Content Type ◽

H Pylori

ABSTRACTHelicobacter pyloriis a Gram-negative bacterium that colonizes the human stomach and contributes to the development of peptic ulcer disease and gastric cancer. The secreted pore-forming toxin VacA is one of the major virulence factors ofH. pylori. In the current study, we show that AZ-521 human gastric epithelial cells are highly susceptible to VacA-induced cell death. Wild-type VacA causes death of these cells, whereas mutant VacA proteins defective in membrane channel formation do not. Incubation of AZ-521 cells with wild-type VacA results in cell swelling, poly(ADP-ribose) polymerase (PARP) activation, decreased intracellular ATP concentration, and lactate dehydrogenase (LDH) release. VacA-induced death of these cells is a caspase-independent process that results in cellular release of histone-binding protein high mobility group box 1 (HMGB1), a proinflammatory protein. These features are consistent with the occurrence of cell death through a programmed necrosis pathway and suggest that VacA can be included among the growing number of bacterial pore-forming toxins that induce cell death through programmed necrosis. We propose that VacA augmentsH. pylori-induced mucosal inflammation in the human stomach by causing programmed necrosis of gastric epithelial cells and subsequent release of proinflammatory proteins and may thereby contribute to the pathogenesis of gastric cancer and peptic ulceration.

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Role of Interleukin-32 in Helicobacter pylori-Induced Gastric Inflammation

Infection and Immunity ◽

10.1128/iai.00637-12 ◽

2012 ◽

Vol 80 (11) ◽

pp. 3795-3803 ◽

Cited By ~ 31

Author(s):

Kosuke Sakitani ◽

Yoshihiro Hirata ◽

Yoku Hayakawa ◽

Takako Serizawa ◽

Wachiko Nakata ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Gastric Mucosa ◽

Cell Lines ◽

Inflammatory Diseases ◽

Nuclear Factor Κb ◽

Gastric Disease ◽

Ags Cells ◽

Content Type ◽

H Pylori

ABSTRACTHelicobacter pyloriinfection is associated with gastritis and gastric cancer. AnH. pylorivirulence factor, thecagpathogenicity island (PAI), is related to host cell cytokine induction and gastric inflammation. Since elucidation of the mechanisms of inflammation is important for therapy, the associations between cytokines and inflammatory diseases have been investigated vigorously. Levels of interleukin-32 (IL-32), a recently described inflammatory cytokine, are increased in various inflammatory diseases, such as rheumatoid arthritis and Crohn's disease, and in malignancies, including gastric cancer. In this report, we examined IL-32 expression in human gastric disease. We also investigated the function of IL-32 in activation of the inflammatory cytokines in gastritis. IL-32 expression paralleled human gastric tissue pathology, with low IL-32 expression inH. pylori-uninfected gastric mucosa and higher expression levels in gastritis and gastric cancer tissues.H. pyloriinfection increased IL-32 expression in human gastric epithelial cell lines.H. pylori-induced IL-32 expression was dependent on the bacterialcagPAI genes and on activation of nuclear factor κB (NF-κB). IL-32 expression induced byH. pyloriwas not detected in the supernatant of AGS cells but was found in the cytosol. Expression of theH. pylori-induced cytokines CXCL1, CXCL2, and IL-8 was decreased in IL-32-knockdown AGS cell lines compared to a control AGS cell line. We also found that NF-κB activation was decreased inH. pylori-infected IL-32-knockdown cells. These results suggest that IL-32 has important functions in the regulation of cytokine expression inH. pylori-infected gastric mucosa.

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Intrafamilial Infection of Helicobacter Pylori: Abnormal Gastric Epithelial Cells, Pedestal-Rich H. Pylori Adherence, and a Gene Mutation in a Child with Protein-Losing Gastroenteropathy

Medical University ◽

10.2478/medu-2019-0013 ◽

2019 ◽

Vol 2 (3) ◽

pp. 83-99

Author(s):

T.W. Wan ◽

O. Khokhlova ◽

W. Higuchi ◽

I. Protasova ◽

Olga V. Peryanova ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Gastric Mucosa ◽

Epithelial Cells ◽

Gene Mutation ◽

Virulence Factor ◽

East Asian ◽

Gastric Epithelium ◽

Gastric Epithelial Cells ◽

H Pylori

Abstract Helicobacter pylori, one of the most prevalent human pathogens, colonizes the gastric mucosa and is associated with gastric diseases, such as gastritis and peptic ulcers, and is also a bacterial risk factor for gastric cancer. Cytotoxin-associated gene A (CagA) protein, a major virulence factor of H. pylori, is phosphorylated in cells at its Glu-Pro-IIe-Tyr-Ala (EPIYA) motif and is considered to trigger gastric cancer. CagA is classified into two forms, Western CagA with EPIYA-ABC and East Asian CagA with EPIYA-ABD, with the latter associated with a high risk of developing gastric cancer. CagA causes morphological transformation of cells, yielding the “hummingbird” phenotype in AGS cells and possibly membranous pedestals in the gastric epithelium, albeit rarely. H. pylori adherence to the gastric mucosa is not yet fully understood. Here, we describe an intrafamilial infection case of H. pylori, focusing on the gastric epithelium, H. pylori adherence, and a gene mutation in a child with protein-losing gastroenteropathy (characterized by excessive loss of plasma proteins into the gastrointestinal tract). H. pylori, which also infected family members (mother and father), was genetically a single clone with the virulence genes of an East Asian type. The patient’ gastric mucosa exhibited some unique features. Endoscopy revealed the presence of protein plugs on the mucosal surface, which were immunoelectrophoretically similar to serum proteins. Electron microscopy revealed abnormal gastric epithelial cells, totally covered with the secretions or possessing small swollen structures and irregular microvilli. The patient’s H. pylori infection was characterized by frequently occurring thick pedestals, formed along adherent H. pylori. The serum protein level returned to normal and the protein plugs disappeared after the successful eradication of H. pylori, albeit with lag periods for healing. He had a mutation in the OCRL1 gene, associated with Dent disease (asymptomatic proteinuria). Thus, in the patient’s gastric mucosa, we found the abnormal gastric epithelial cells, which may be caused by an OCRL1 mutation or H. pylori, and pedestal-rich H. pylori infection, possibly caused by a higher level of action of CagA in the abnormal epithelial cells. The data suggests a novel H. pylori virulence factor associated with “excessive plasma protein release”.

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Increased expression of the urokinase plasminogen activator system by Helicobacter pylori in gastric epithelial cells

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.90283.2008 ◽

2008 ◽

Vol 295 (3) ◽

pp. G431-G441 ◽

Cited By ~ 20

Author(s):

Susan Kenny ◽

Cedric Duval ◽

Stephen J. Sammut ◽

Islay Steele ◽

D. Mark Pritchard ◽

...

Keyword(s):

Gastric Cancer ◽

Cell Proliferation ◽

Helicobacter Pylori ◽

Epithelial Cells ◽

Plasminogen Activator ◽

Egf Receptor ◽

Gastric Epithelial Cells ◽

Epithelial Cell Proliferation ◽

H Pylori ◽

Pai 1

The gastric pathogen Helicobacter pylori ( H. pylori) is linked to peptic ulcer and gastric cancer, but the relevant pathophysiological mechanisms are unclear. We now report that H. pylori stimulates the expression of plasminogen activator inhibitor (PAI)-1, urokinase plasminogen activator (uPA), and its receptor (uPAR) in gastric epithelial cells and the consequences for epithelial cell proliferation. Real-time PCR of biopsies from gastric corpus, but not antrum, showed significantly increased PAI-1, uPA, and uPAR in H. pylori-positive patients. Transfection of primary human gastric epithelial cells with uPA, PAI-1, or uPAR promoters in luciferase reporter constructs revealed expression of all three in H+/K+ATPase- and vesicular monoamine transporter 2-expressing cells; uPA was also expressed in pepsinogen- and uPAR-containing trefoil peptide-1-expressing cells. In each case expression was increased in response to H. pylori and for uPA, but not PAI-1 or uPAR, required the virulence factor CagE. H. pylori also stimulated soluble and cell surface-bound uPA activity, and both were further increased by PAI-1 knockdown, consistent with PAI-1 inhibition of endogenous uPA. H. pylori stimulated epithelial cell proliferation, which was inhibited by uPA immunoneutralization and uPAR knockdown; exogenous uPA also stimulated proliferation that was further increased after PAI-1 knockdown. The proliferative effects of uPA were inhibited by immunoneutralization of the EGF receptor and of heparin-binding EGF (HB-EGF) by the mutant diphtheria toxin CRM197 and an EGF receptor tyrosine kinase inhibitor. H. pylori induction of uPA therefore leads to epithelial proliferation through activation of HB-EGF and is normally inhibited by concomitant induction of PAI-1; treatments directed at inhibition of uPA may slow the progression to gastric cancer.

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Identification of Functional Interactome of Gastric Cancer Cells with Helicobacter pylori Outer Membrane Protein HpaA by HPLC-MS/MS

BioMed Research International ◽

10.1155/2020/1052926 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Ruyue Fan ◽

Xiurui Han ◽

Di Xiao ◽

Lihua He ◽

Yanan Gong ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Epithelial Cells ◽

Membrane Protein ◽

Outer Membrane ◽

Cell Lines ◽

Outer Membrane Protein ◽

Regulation Of Transcription ◽

Gastric Epithelial Cells ◽

H Pylori

HpaA as an outer membrane protein of Helicobacter pylori (H. pylori) plays a significant role in the adhesion to the human stomach, but the functional relation between HpaA and gastric epithelial cells is still not clear. To screen the interaction between HpaA and cellular proteins in gastric epithelial cells, the HpaA protein from H. pylori 26695 fused with a tag (6× His) was expressed and purified successfully, the secondary structure was estimated by the Circular Dichroism (CD) spectrum, and the purified recombinant protein was used to perform the pull-down assays with gastric cancer cell lines (AGS and SGC-7901) lysates, respectively. The pull-down proteins were identified by high-performance liquid chromatography tandem mass spectrometry system (HPLC-MS/MS). A total of 9 and 13 proteins related were analyzed from AGS and SGC-7901 cell lysates, respectively. ANXA2 was considered as putative HpaA functional partner discovered from lysates of both cell lines with high score and coverage. It is hypothesized that HpaA may be involved in the biological process of regulation of transcription and nucleic acid metabolism during the adhesion of H. pylori to human gastric epithelial cells, and HpaA-binding proteins also be used as targets for the development of antiadhesion drugs against H. pylori.

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Ceramide and Toll-Like Receptor 4 Are Mobilized into Membrane Rafts in Response to Helicobacter pylori Infection in Gastric Epithelial Cells

Infection and Immunity ◽

10.1128/iai.05856-11 ◽

2012 ◽

Vol 80 (5) ◽

pp. 1823-1833 ◽

Cited By ~ 32

Author(s):

Dah-Yuu Lu ◽

Hui-Chen Chen ◽

Mei-Shiang Yang ◽

Yuan-Man Hsu ◽

Hwai-Jeng Lin ◽

...

Keyword(s):

Helicobacter Pylori ◽

Epithelial Cells ◽

Lipid Rafts ◽

Gastric Epithelial Cells ◽

Toll Like Receptor ◽

Tlr4 Expression ◽

Ags Cells ◽

Content Type ◽

Infected Cells ◽

H Pylori

ABSTRACTHelicobacter pyloriinfection is thought to be involved in the development of several gastric diseases. TwoH. pylorivirulence factors (vacuolating cytotoxin A and cytotoxin-associated gene A) reportedly interact with lipid rafts in gastric epithelial cells. The role of Toll-like receptor (TLR)-mediated signaling in response toH. pyloriinfection has been investigated extensively in host cells. However, the receptor molecules in lipid rafts that are involved inH. pylori-induced innate sensing have not been well characterized. This study investigated whether lipid rafts play a role inH. pylori-induced ceramide secretion and TLR4 expression and thereby contribute to inflammation in gastric epithelial cells. We observed that both TLR4 and MD-2 mRNA and protein levels were significantly higher inH. pylori-infected AGS cells than in mock-infected cells. Moreover, significantly more TLR4 protein was detected in detergent-resistant membranes extracted fromH. pylori-infected AGS cells than in those extracted from mock-infected cells. However, this effect was attenuated by the treatment of cells with cholesterol-usurping agents, suggesting thatH. pylori-induced TLR4 signaling is dependent on cholesterol-rich microdomains. Similarly, the level of cellular ceramide was elevated and ceramide was translocated into lipid rafts afterH. pyloriinfection, leading to interleukin-8 (IL-8) production. Using the sphingomyelinase inhibitor imipramine, we observed thatH. pylori-induced TLR4 expression was ceramide dependent. These results indicate the mobilization of ceramide and TLR4 into lipid rafts byH. pyloriinfection in response to inflammation in gastric epithelial cells.

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Chemokines and Antimicrobial Peptides Have acag-Dependent Early Response to Helicobacter pylori Infection in Primary Human Gastric Epithelial Cells

Infection and Immunity ◽

10.1128/iai.01517-13 ◽

2014 ◽

Vol 82 (7) ◽

pp. 2881-2889 ◽

Cited By ~ 19

Author(s):

Pascale Mustapha ◽

Isabelle Paris ◽

Magali Garcia ◽

Cong Tri Tran ◽

Julie Cremniter ◽

...

Keyword(s):

Helicobacter Pylori ◽

Epithelial Cells ◽

Inflammatory Response ◽

Antimicrobial Peptides ◽

Virulence Factors ◽

Inflammatory Mediator ◽

Host Cells ◽

Gastric Epithelial Cells ◽

Content Type ◽

H Pylori

ABSTRACTHelicobacter pyloriinfection systematically causes chronic gastric inflammation that can persist asymptomatically or evolve toward more severe gastroduodenal pathologies, such as ulcer, mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric cancer. Thecagpathogenicity island (cagPAI) ofH. pyloriallows translocation of the virulence protein CagA and fragments of peptidoglycan into host cells, thereby inducing production of chemokines, cytokines, and antimicrobial peptides. In order to characterize the inflammatory response toH. pylori, a new experimental protocol for isolating and culturing primary human gastric epithelial cells was established using pieces of stomach from patients who had undergone sleeve gastrectomy. Isolated cells expressed markers indicating that they were mucin-secreting epithelial cells. Challenge of primary epithelial cells withH. pyloriB128 underscored early dose-dependent induction of expression of mRNAs of the inflammatory mediators CXCL1 to -3, CXCL5, CXCL8, CCL20, BD2, and tumor necrosis factor alpha (TNF-α). In AGS cells, significant expression of only CXCL5 and CXCL8 was observed following infection, suggesting that these cells were less reactive than primary epithelial cells. Infection of both cellular models withH. pyloriB128ΔcagM, acagPAI mutant, resulted in weak inflammatory-mediator mRNA induction. At 24 h after infection of primary epithelial cells withH. pylori, inflammatory-mediator production was largely due tocagPAI substrate-independent virulence factors. Thus,H. pyloricagPAI substrate appears to be involved in eliciting an epithelial response during the early phases of infection. Afterwards, other virulence factors of the bacterium take over in development of the inflammatory response. Using a relevant cellular model, this study provides new information on the modulation of inflammation duringH. pyloriinfection.

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Engagement of CEACAM1 by Helicobacter pylori HopQ Is Important for the Activation of Non-Canonical NF-κB in Gastric Epithelial Cells

Microorganisms ◽

10.3390/microorganisms9081748 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1748

Author(s):

Karin Taxauer ◽

Youssef Hamway ◽

Anna Ralser ◽

Alisa Dietl ◽

Karin Mink ◽

...

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Epithelial Cells ◽

Surface Protein ◽

Host Cells ◽

Gastric Epithelial Cells ◽

Gastric Cancer Cells ◽

Tissue Samples ◽

Mutant Strains ◽

H Pylori

The gastric pathogen Helicobacter pylori infects half of the world’s population and is a major risk factor for gastric cancer development. In order to attach to human gastric epithelial cells and inject the oncoprotein CagA into host cells, H. pylori utilizes the outer membrane protein HopQ that binds to the cell surface protein CEACAM, which can be expressed on the gastric mucosa. Once bound, H. pylori activates a number of signaling pathways, including canonical and non-canonical NF-κB. We investigated whether HopQ–CEACAM interaction is involved in activating the non-canonical NF-κB signaling pathway. Different gastric cancer cells were infected with the H. pylori wild type, or HopQ mutant strains, and the activation of non-canonical NF-κB was related to CEACAM expression levels. The correlation between CEACAM levels and the activation of non-canonical NF-κB was confirmed in human gastric tissue samples. Taken together, our findings show that the HopQ–CEACAM interaction is important for activation of the non-canonical NF-κB pathway in gastric epithelial cells.

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