Project description:Helicobacter pylori are gram-negative bacteria that colonize the human stomach and are the major etiological factor in gastric carcinoma development. The aim of this work was to evaluate changes in gene expression in gastric cells induced by H. pylori.
Project description:Helicobacter pylori are gram-negative bacteria that colonize the human stomach and are the major etiological factor in gastric carcinoma development. The aim of this work was to evaluate changes in gene expression in gastric cells induced by H. pylori. The human gastric carcinoma-derived cell line AGS was infected with H. pylori strain 60190 (ATCC 49503) for 24 hours. RNA was extracted from three independent experiments.
Project description:Helicobacter pylori clinical isolates can establish themselves in gastric epithelial stem cells and this interaction may have implications for gastric tumorigenesis. Mouse gastric epithelial progenitor cells (mGEPs) and non-progenitor gastric epithelial cells (npGECs) were infected for 24hrs with Helicobacter pylori clinical isolates Kx1 and Kx2. Kx1 was isolated from a patient with chronic atrophic gastritis (ChAG) and Kx2 from the same patient 4 years later, when he progressed to gastric adenocarcinoma. Keywords: RNA Expression Array
Project description:Helicobacter pylori clinical isolates can establish themselves in gastric epithelial stem cells and this interaction may have implications for gastric tumorigenesis. Mouse gastric epithelial progenitor cells (mGEPs) were infected for 24hrs with Helicobacter pylori clinical isolates Kx1 and Kx2. Kx1 and Kx2 were also grown in cell media in the absence of cells. Kx1 was isolated from a patient with chronic atrophic gastritis (ChAG) and Kx2 from the same patient 4 years later, when he progressed to gastric adenocarcinoma. Keywords: RNA Expression Array
Project description:This group is focusing on the molecular mechanisms of the biosynthesis of glycoconjugates and carbohydrate ligands important in the process of gastric carcinogenesis and on gastric carcinoma progression and metastasis. The adhesion of H. pylori to epithelial cells induces a variety of modifications, including changes in cell morphology,cytokine production and release, alterations in glycosylation and in the biosynthesis of mucins. This study aims to identify the gene expression changes in the gastric epithelial cells (AGS) induced by Helicobacter pylori infection. This experiment was performed as previously described in the literature by submitting a gastric cell line to co-culture with reference strains of H. pylori.
Project description:The purpose of the study was to define gastric cell-specific proteomic changes, induced by H. pylori oncogenic strains, that are critical for initiation of the gastric carcinogenic cascade. Gastric cell scrapings were harvested from H. pylori-infected and uninfected animals for quantitative proteomic analyses using isobaric tags for relative and absolute quantitation (iTRAQ). Canonical and disease pathway mapping using Ingenuity Pathway Analysis (IPA) identified significantly altered inflammatory and cancer-signaling pathways that included Rab/Ras signaling proteins.
Project description:This group is focusing on the molecular mechanisms of the biosynthesis of glycoconjugates and carbohydrate ligands important in the process of gastric carcinogenesis and on gastric carcinoma progression and metastasis. The adhesion of H. pylori to epithelial cells induces a variety of modifications, including changes in cell morphology,cytokine production and release, alterations in glycosylation and in the biosynthesis of mucins. This study aims to identify the gene expression changes in the gastric epithelial cells (AGS) induced by Helicobacter pylori infection. This experiment was performed as previously described in the literature by submitting a gastric cell line to co-culture with reference strains of H. pylori. The following RNA samples (in triplicate) were analyzed by hybridization to the GLYCOv2 array: 1)Gastric cell line co-culture with H. pylori strain A(High Patogenicity) 2)Gastric cell line co-culture with H. pylori strain B(Low Patogenicity) 3)Gastric cell line without H. pylori co-culture (control)
Project description:Background: Helicobacter pylori has been shown to alter the secretion of gastric hormones that modulate body fat deposition. Since cag-positive H. pylori strains interact intimately with the host gastric epithelial cells and trigger higher inflammation than cag-negative strains, we hypothesized that gastric colonization with H. pylori strains without functional cagA ameliorates obesity and its complications by modulating gastric gene expression and inflammation. Methodology/Principal Findings: To test this hypothesis we examined the effects of gastric colonization on metabolic and inflammatory markers in mice infected with two isogenic strains of H. pylori: 26695 strain 98-325 (cagA+ wild-type) and its cag pathogenicity island (cagPAI) mutant strain 99-305, a knockout made by inserting a chloramphenicol resistance cassette. Only the cagPAI mutant decreased fasting blood glucose levels, improved glucose tolerance and suppressed weight gain in db/db mice and mice with diet-induced obesity. These effects were associated with increased gastric leptin levels, suppressed infiltration of macrophages, enhanced influx of regulatory T cells (Treg) in adipose tissue and suppressed gastric inflammation. Gene set enrichment analyses of gastric mucosal samples identified six differentially modulated pathways, including the Hedgehog signaling pathway that is associated with control of cellular proliferation and gastric carcinogenesis as well as the insulin signaling pathway. Conclusions/Significance: Gastric colonization with cagPAI-negative strains of H. pylori ameliorate obesity and inflammation by modulating gastric gene expression, suggesting that cag-negative H. pylori strains might be beneficial in ameliorating obesity and its co-morbidities.
Project description:Helicobacter pylori infection reprograms host gene expression and influences various cellular processes, which have been investigated by cDNA microarray in vitro culture cells and in vivo patients of the chronic abdominal complaint. In this study,the effects of H. pylori infection on host gene expression in the gastric antral mucosa of patients with chronic gastritis were examined.
Project description:Helicobacter pylori clinical isolates can establish themselves in gastric epithelial stem cells and this interaction may have implications for gastric tumorigenesis. Mouse gastric epithelial progenitor cells (mGEPs) were infected for 24hrs with Helicobacter pylori clinical isolates Kx1 and Kx2. Kx1 and Kx2 were also grown in cell media in the absence of cells. Kx1 was isolated from a patient with chronic atrophic gastritis (ChAG) and Kx2 from the same patient 4 years later, when he progressed to gastric adenocarcinoma. Keywords: RNA Expression Array H. pylori strains Kx1 or Kx2 that had been grown to log phase were used to infect mGEP cells.. After 24h, media and non-attached bacteria were washed off and the cells harvested by trypsinization. RNA was prepared from bacteria infecting mGEP cells or bacterial cultures of Kx1 and Kx2 grown in cell media for 24h in the absence of mGEP cells.