Gene expression in vivo shows that Helicobacter pylori colonizes an acidic niche on the gastric surface

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

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Dual Control of Helicobacter pylori Heat Shock Gene Transcription by HspR and HrcA

Journal of Bacteriology ◽

10.1128/jb.186.10.2956-2965.2004 ◽

2004 ◽

Vol 186 (10) ◽

pp. 2956-2965 ◽

Cited By ~ 26

Author(s):

Gunther Spohn ◽

Alberto Danielli ◽

Davide Roncarati ◽

Isabel Delany ◽

Rino Rappuoli ◽

...

Keyword(s):

Gene Expression ◽

Helicobacter Pylori ◽

Heat Shock ◽

Heat Shock Gene ◽

Inverted Repeats ◽

Dual Control ◽

Shock Gene ◽

Heat Shock Gene Expression ◽

H Pylori

ABSTRACT The HspR repressor regulates transcription of the groESL, hrcA-grpE-dnaK, and cbpA-hspR-orf operons of Helicobacter pylori. Here we show that two of the HspR-regulated operons, namely, the groESL and dnaK operons, encoding the major cellular chaperone machineries are also regulated by the H. pylori homologue of the HrcA repressor. Similarly to the hspR mutation, deletion of the hrcA gene also leads to complete derepression of the P gro and P hrc promoters. The presence of both HspR and HrcA is therefore necessary for regulated transcription from these promoters. HrcA binds directly to P gro and P hrc , likely contacting two inverted repeats with similarity to the CIRCE motif, which are present on both promoters. HrcA regulation is, however, shown to depend on binding of the HspR protein, since deletion of the HspR-binding site of the P gro promoter leads to loss of heat inducibility of this promoter. In contrast, transcription from the P cbp promoter is regulated solely by HspR. HspR is also shown to form oligomers in vivo through a stretch of hydrophobic repeats between amino acid positions 66 and 97. The implications of these findings for the elucidation of the networks regulating heat shock gene expression in H. pylori are discussed.

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cDNA Array Analysis of cag Pathogenicity Island-Associated Helicobacter pylori Epithelial Cell Response Genes

Infection and Immunity ◽

10.1128/iai.69.11.6970-6980.2001 ◽

2001 ◽

Vol 69 (11) ◽

pp. 6970-6980 ◽

Cited By ~ 70

Author(s):

Joanne M. Cox ◽

Christopher L. Clayton ◽

Toshihiko Tomita ◽

Don M. Wallace ◽

Philip A. Robinson ◽

...

Keyword(s):

Gene Expression ◽

Helicobacter Pylori ◽

Epithelial Cells ◽

Cdna Array ◽

Pathogenicity Island ◽

High Density ◽

Differentially Expressed ◽

Gastric Epithelial Cells ◽

H Pylori

ABSTRACT Helicobacter pylori strains containing thecag pathogenicity island (PAI) induce NF-κB activation and interleukin-8 secretion in gastric epithelial cells. The aim of this study was to investigate changes in epithelial gene expression induced by cag PAI-positive and -negative strains ofH. pylori using high-density cDNA array hybridization technology. Radio-labeled cDNA prepared from H. pylori-infected Kato 3 gastric epithelial cells was hybridized to high-density cDNA arrays to identify changes in epithelial gene expression compared to noninfected controls. In vivo expression of selected, differentially expressed genes was examined by reverse transcription-PCR analysis of H. pylori-positive and -negative gastric mucosa. Screening of ca. 57,800 cDNAs identified 208 known genes and 48 novel genes and/or expressed sequence tags of unknown function to be differentially expressed in Kato 3 cells following H. pylori infection. Marked differences in gene expression profiles were observed following cagPAI-positive and cag PAI-negative infection with 15 novel cDNAs and 92 known genes being differentially expressed. H. pylori was found to change the expression of genes encoding growth factors and cytokine/chemokines and their receptors, apoptosis proteins, transcription factors and metalloprotease-disintegrin proteins (ADAMs), and tissue inhibitors of metalloproteinases. Gastric differential expression of selected known genes (amphiregulin and ADAM 10) and a novel gene (HPYR1) was confirmed in vivo in patients with H. pylori infection. Confirmation of the in vivo expression of selected genes demonstrates the usefulness of this approach for investigating pathogen-induced changes in host gene expression.

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In vivo lipid peroxidation and platelet activation in Helicobacter pylori infection

Gastroenterology ◽

10.1016/s0016-5085(01)83333-3 ◽

2001 ◽

Vol 120 (5) ◽

pp. A670-A670

Author(s):

M NERI ◽

G DAVI ◽

D FESTI ◽

F LATERZA ◽

A FALCO ◽

...

Keyword(s):

Lipid Peroxidation ◽

Helicobacter Pylori ◽

Platelet Activation ◽

Helicobacter Pylori Infection

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A Cre-loxP based mouse model for conditional somatic gene expression and knock-down in vivo using avian retroviral vectors

Zeitschrift für Gastroenterologie ◽

10.1055/s-0028-1089500 ◽

2008 ◽

Vol 46 (09) ◽

Author(s):

B Seidler ◽

A Schmidt ◽

U Mayr ◽

H Nakkhei ◽

RM Schmid ◽

...

Keyword(s):

Gene Expression ◽

Mouse Model ◽

Retroviral Vectors ◽

Knock Down ◽

Somatic Gene

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Helicobacter pylori induziert Gastritis in vivo durch die Inhibition des Tumorsuppressors Caveolin-1 mittels des Cholesterol-gesteuerten Transkriptionsfaktors SREBP1

Zeitschrift für Gastroenterologie ◽

10.1055/s-0033-1352834 ◽

2013 ◽

Vol 51 (08) ◽

Author(s):

E Burgermeister ◽

I Hikova ◽

C Röcken ◽

R Vogelmann ◽

MP Ebert

Keyword(s):

Helicobacter Pylori ◽

Caveolin 1

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Identification of genes early responsive to gamma-irradiation in isolated rat hepatocytes in vitro and rat liver in vivo by cDNA array gene expression analysis

Zeitschrift für Gastroenterologie ◽

10.1055/s-2005-920060 ◽

2005 ◽

Vol 43 (05) ◽

Author(s):

DS Batusic ◽

H Christiansen ◽

B Saile ◽

RM Hermann ◽

J Dudas ◽

...

Keyword(s):

Gene Expression ◽

Gamma Irradiation ◽

Rat Liver ◽

Gene Expression Analysis ◽

Cdna Array ◽

Rat Hepatocytes ◽

Isolated Rat Hepatocytes ◽

Isolated Rat

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Effect of X-irradiation on gene expression of rat liver chemokines: in vivo and in vitro studies

Zeitschrift für Gastroenterologie ◽

10.1055/s-2008-1037499 ◽

2008 ◽

Vol 46 (01) ◽

Cited By ~ 1

Author(s):

F Moriconi ◽

H Christiansen ◽

N Sheikh ◽

J Dudas ◽

...

Keyword(s):

Gene Expression ◽

Rat Liver ◽

In Vitro Studies ◽

X Irradiation

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Vibrio harveyi virulence gene expression in vitro and in vivo during infection in black tiger shrimp Penaeus monodon

Diseases of Aquatic Organisms ◽

10.3354/dao03475 ◽

2020 ◽

Vol 139 ◽

pp. 153-160

Author(s):

S Peeralil ◽

TC Joseph ◽

V Murugadas ◽

PG Akhilnath ◽

VN Sreejith ◽

...

Keyword(s):

Gene Expression ◽

Virulence Genes ◽

Vibrio Harveyi ◽

Penaeus Monodon ◽

Challenge Test ◽

Virulence Gene ◽

Economic Losses ◽

Virulence Gene Expression

Luminescent Vibrio harveyi is common in sea and estuarine waters. It produces several virulence factors and negatively affects larval penaeid shrimp in hatcheries, resulting in severe economic losses to shrimp aquaculture. Although V. harveyi is an important pathogen of shrimp, its pathogenicity mechanisms have yet to be completely elucidated. In the present study, isolates of V. harveyi were isolated and characterized from diseased Penaeus monodon postlarvae from hatcheries in Kerala, India, from September to December 2016. All 23 tested isolates were positive for lipase, phospholipase, caseinase, gelatinase and chitinase activity, and 3 of the isolates (MFB32, MFB71 and MFB68) showed potential for significant biofilm formation. Based on the presence of virulence genes, the isolates of V. harveyi were grouped into 6 genotypes, predominated by vhpA+ flaB+ ser+ vhh1- luxR+ vopD- vcrD+ vscN-. One isolate from each genotype was randomly selected for in vivo virulence experiments, and the LD50 ranged from 1.7 ± 0.5 × 103 to 4.1 ± 0.1 × 105 CFU ml-1. The expression of genes during the infection in postlarvae was high in 2 of the isolates (MFB12 and MFB32), consistent with the result of the challenge test. However, in MFB19, even though all genes tested were present, their expression level was very low and likely contributed to its lack of virulence. Because of the significant variation in gene expression, the presence of virulence genes alone cannot be used as a marker for pathogenicity of V. harveyi.

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