Gastric cancer exosomes contribute to the field cancerization of gastric epithelial cells surrounding gastric cancer

243 Background: Helicobacter pylori ( H. pylori) is the strongest known risk factor for gastric cancer. Bacterial degradation of tumor suppressor proteins affect the host microbe’s interactions and host cellular response, which contribute to tumorigenesis. p14ARF, a crucial tumor suppressor protein that activates p53 protein under oncogenic stress plays a major role in oncogenic stress response (OSR) regulation. However, little is known about the mechanism of ARF and OSR regulation in H. pylori-infected gastric epithelial cells. Methods: The expression of p14ARF and cytotoxin-associated gene A (CagA) were analyzed in gastric cells co-cultured with H. pylori strains isolated from high-gastric risk and low-gastric risk areas by immunoblotting. To investigate the potential role of CagA in regulation of p14ARF, we employed isogenic cagA− and cagE− H. pylori mutants in gastric epithelial cells, and C57BL/6 mice (n = 10). We also analyzed the expression of Siva1 in human individual infected with cagA-positive (n = 13) and cagA-negative (n = 13) bacteria as well as uninfected human subjects (n = 6). siRNA was used to inhibit activity of Siva1 protein. Results: In this study, H. pylori strains expressing high levels of CagA virulence factor and associated with a higher gastric cancer risk more strongly suppress p14ARF compared with low-risk strains in vivo and in vitro. We found that degradation of p14ARF induced by CagA is mediated by E3 ubiquitin ligase Siva1, which works in concert with another E3 ubiquitin ligase TRIP12. Decreased expression of Siva1 protein and consequent up-regulation of p14ARF was also found in gastric mucosa of H. pylori-infected mice and human individuals. Tumorigenic strain 7.13 was more potent in upregulation of Siva1 and downregulation of p14ARF than non-tumorigenic strain B128. Inhibition of p14ARF protein by H. pylori causes inhibition of autophagy in infected cells. Conclusions: Our results provide first evidence that carcinogenic H. pylori strains significantly alter the host tumor suppressor protein p14ARF, leading to suppression of host OSR and autophagy, which may affect host-bacteria interactions and tumorigenic alteration in the stomach.

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

Infection and Immunity ◽

10.1128/iai.01182-12 ◽

2013 ◽

Vol 81 (7) ◽

pp. 2468-2477 ◽

Cited By ~ 16

Author(s):

Alexander Sheh ◽

Rupesh Chaturvedi ◽

D. Scott Merrell ◽

Pelayo Correa ◽

Keith T. Wilson ◽

...

Keyword(s):

Gene Expression ◽

Gastric Cancer ◽

Helicobacter Pylori ◽

Epithelial Cells ◽

Gastric Disease ◽

Gastric Epithelial Cells ◽

Gastric Cancer Risk ◽

Content Type ◽

H Pylori ◽

Induced Apoptosis

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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Loss of E-cadherin in mouse gastric epithelial cells induces signet ring-like cells, a possible precursor lesion of diffuse gastric cancer

Cancer Science ◽

10.1111/j.1349-7006.2011.01890.x ◽

2011 ◽

Vol 102 (5) ◽

pp. 942-950 ◽

Cited By ~ 27

Author(s):

Ayako Mimata ◽

Hiroshi Fukamachi ◽

Yoshinobu Eishi ◽

Yasuhito Yuasa

Keyword(s):

Gastric Cancer ◽

Epithelial Cells ◽

Diffuse Gastric Cancer ◽

Gastric Epithelial Cells ◽

Precursor Lesion ◽

Signet Ring ◽

E Cadherin

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Molecular anatomy and pathogenic actions of Helicobacter pylori CagA that underpin gastric carcinogenesis

Cellular and Molecular Immunology ◽

10.1038/s41423-019-0339-5 ◽

2019 ◽

Vol 17 (1) ◽

pp. 50-63 ◽

Cited By ~ 17

Author(s):

Atsushi Takahashi-Kanemitsu ◽

Christopher T. Knight ◽

Masanori Hatakeyama

Keyword(s):

Gastric Cancer ◽

Helicobacter Pylori ◽

Epithelial Cells ◽

Tyrosine Phosphorylation ◽

Gastric Carcinogenesis ◽

Host Cells ◽

Gastric Epithelial Cells ◽

Cancer Hallmarks ◽

Hit And Run

AbstractChronic infection with Helicobacter pylori cagA-positive strains is the strongest risk factor for gastric cancer. The cagA gene product, CagA, is delivered into gastric epithelial cells via the bacterial type IV secretion system. Delivered CagA then undergoes tyrosine phosphorylation at the Glu-Pro-Ile-Tyr-Ala (EPIYA) motifs in its C-terminal region and acts as an oncogenic scaffold protein that physically interacts with multiple host signaling proteins in both tyrosine phosphorylation-dependent and -independent manners. Analysis of CagA using in vitro cultured gastric epithelial cells has indicated that the nonphysiological scaffolding actions of CagA cell-autonomously promote the malignant transformation of the cells by endowing the cells with multiple phenotypic cancer hallmarks: sustained proliferation, evasion of growth suppressors, invasiveness, resistance to cell death, and genomic instability. Transgenic expression of CagA in mice leads to in vivo oncogenic action of CagA without any overt inflammation. The in vivo oncogenic activity of CagA is further potentiated in the presence of chronic inflammation. Since Helicobacter pylori infection triggers a proinflammatory response in host cells, a feedforward stimulation loop that augments the oncogenic actions of CagA and inflammation is created in CagA-injected gastric mucosa. Given that Helicobacter pylori is no longer colonized in established gastric cancer lesions, the multistep nature of gastric cancer development should include a “hit-and-run” process of CagA action. Thus, acquisition of genetic and epigenetic alterations that compensate for CagA-directed cancer hallmarks may be required for completion of the “hit-and-run” process of gastric carcinogenesis.

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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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