Enlarged Fold Gastritis Research Articles

Prostate Stem Cell Antigen Gene Polymorphism Is Associated with H. pylori-related Promoter DNA Methylation in Nonneoplastic Gastric Epithelium.

Genome-wide association study identified two functional SNPs associated with gastric cancer especially the diffuse type. The first was a polymorphism (rs2294008) in prostate stem cell antigen (PSCA), and the other was a polymorphism (rs4072037) in mucin 1 (MUC1). DNA methylation is associated with gastric cancer and Helicobacter pylori (H. pylori)-induced gastritis, while hypermethylation of promoter CpG island (CGI) is a common characteristic of enlarged-fold gastritis induced by H. pylori, a risk factor of diffuse-type gastric cancer. We evaluated the association between PSCA and MUC1 polymorphisms with H. pylori--related promoter CGI methylation in the nonneoplastic gastric mucosa. PSCA rs2294008 C/T and MUC1 rs4072037 A/G polymorphisms were genotyped in 410 cancer-free subjects in relation to promoter CGI methylation status of three candidate genes, of which the methylation status is associated with H. pylori infection (IGF2, MYOD1, and SLC16A12). Methylation levels of all three genes were significantly higher in subjects with PSCA rs2294008 T/T compared with the PSCA rs2294008 C/C (all P < 0.05). Such associations were more enhanced in H. pylori-positive subjects (all P < 0.01). The multivariate analysis demonstrated that PSCA C/T [OR, 2.37; 95% CI (confidence interval), 1.06-5.29; P = 0.035] and T/T genotypes (OR, 3.2; 95% CI, 1.41-7.25; P = 0.005) were significantly associated with methylation-high gastric mucosa as independent factors. MUC1 rs4072037 A/G polymorphism was not associated with methylation status of all three genes. PSCA C/T and T/T genotypes are associated with H. pylori-related promoter DNA methylation in the gastric mucosa.Impact: Our observations provided the evidence that PSCA polymorphism influence the susceptibility to gastric cancer through DNA methylation induction.

Role of DNA Methylation in the Development of Diffuse-Type Gastric Cancer

Cancer cells exhibit two opposing methylation abnormalities: genome-wide hypomethylation and gene promoter hypermethylation. Downregulation of E-cadherin (CDH1) plays a key role in the development of diffuse-type gastric cancer, and DNA methylation is a major cause of the gene’s silencing. Hereditary diffuse gastric cancer is caused by germline mutation of CDH1 gene, and DNA methylation frequently serves as the second hit completely inactivating the gene. In sporadic diffuse-type gastric cancer, methylation of CDH1 is more prevalent than mutation of the gene. Epstein-Barr virus (EBV)-associated gastric carcinoma (EBV-associated GC) is characterized by concurrent methylation of multiple genes, and diffuse-type gastric cancer is frequently seen among EBV-associated GCs. Patients with pangastritis or enlarged-fold gastritis, which are both caused by Helicobacter pylori infection, reportedly have an increased risk for diffuse-type gastric cancer. Notably, the gastric mucosa of enlarged-fold gastritis patients exhibits CDH1 hypermethylation and genome-wide hypomethylation. These data suggest that aberrant DNA methylation is an essential promoter of carcinogenesis in individuals at high risk for diffuse-type gastric cancer.

&lt;i&gt;H. pylori&lt;/i&gt;-Eradication Therapy Increases RUNX3 Expression in the Glandular Epithelial Cells in Enlarged-Fold Gastritis

Helicobacter pylori (HP)-eradication therapy increases Runt domain transcription factor 3 (RUNX3) expression in the glandular epithelial cells in enlarged-fold gastritis. The aim of this study is to evaluate expression of the RUNX3 protein, the product of a gastric tumor suppression gene, and mutagenic oxidative stress in human gastric mucosal specimens obtained from patients with HP-induced enlarged-fold gastritis. Methods. RUNX3 expression was immunohistochemically scored and the degree of the mucosal oxidative stress was directly measured by the chemiluminescense (ChL) assay in the biopsy specimens. Results. RUNX3 expression was detected in the gastric epithelial cells. HP-eradication significantly increased RUNX3 expression in the glandular epithelium of the corpus, however, no change was observed in those of the antrum. A fourfold higher mucosal ChL value was observed in the corpus as compared with that in the antrum. HP-eradication significantly decreased the mucosal ChL values in both portions of the stomach to nearly undetectable levels. Conclusion. The glandular epithelium is exposed to a high level of carcinogenic oxidative stress and shows low levels of expression of the tumor suppressive molecule, RUNX3; however, this expression was restored after HP-eradication, suggesting the high risk of carcinogenesis associated with HP-induced enlarged-fold gastritis of the corpus.

T1628 Genome-Wide Hypomethylation Associated with Regional Hypermethylation in H. pylori-Related Enlarged Fold Gastritis

G A A b st ra ct s STAT3mRNA and protein in a dose dependent manner without alteration in cellular phophoSTAT3 level. The concentration of VacA was appropriated with 120nM for the following experiments. Relative mRNA expression levels of Bcl-2 and Bcl-XL were significantly decreased, and their cellular protein levels were substantially decreased thereafter. Knockdown of STAT3, Bcl-2 and Bcl-XL but not Mcl-1 by siRNA induced significant apoptosis in AZ-521 cells, which augmented VacA-induced apoptosis. The reduction in STAT3, Bcl2 and Bcl-XL and resultant apoptosis were affected by a JNK inhibitor I but not bafilomycin A1, a vacuolating inhibitor. Conclusion: VacA causes reduction of cellular levels of STAT3 and its downstream transcribed molecules, Bcl-2 and Bcl-XL, leading to apoptosis. This novel action of VacA is at least in part dependent on JNK pathway, providing new insights on the molecular mechanisms of VacA-induced apoptosis.

LINE-1 Hypomethylation Is Associated with Increased CpG Island Methylation in Helicobacter pylori–Related Enlarged-Fold Gastritis

The molecular mechanism by which Helicobacter pylori infection leads to gastric cancer is not fully understood. Similarly, patients with enlarged-fold (EF+) gastritis, one cause of which is H. pylori infection, have an increased risk for gastric cancer, although again molecular mechanism is unclear. In the present study, we analyzed the methylation status of long interspersed nucleotide elements (LINE-1) and three cancer-related genes in a panel of gastric mucosae, with or without EF+ gastritis. We used bisulfite pyrosequencing to assess the levels of LINE-1, CDH1, CDH13, and PGP9.5 methylation in 78 gastric mucosa specimens from 48 patients. Levels of LINE-1 methylation were significantly reduced in mucosae from patients with EF+ gastritis. This hypomethylation of LINE-1 was associated with increased methylation of the 5' CpG islands of the genes, which suggests that, in EF+ gastritis, the methylation of the promoter regions of certain genes is accompanied by global demethylation of repetitive sequences. Our results indicate that genomewide hypomethylation and regional hypermethylation occur in EF+ gastritis and may contribute to the tumorigenesis of diffuse-type gastric cancers.

E‐cadherin Gene Promoter Hypermethylation in H. pylori‐Induced Enlarged Fold Gastritis

Promoter hypermethylation of E-cadherin plays an important role on gastric carcinogenesis. We have previously reported that the odds ratio for gastric carcinoma and the prevalence of diffuse-type early gastric carcinoma in Helicobacter pylori-induced enlarged fold gastritis increased with increasing fold width. Thus, we examined E-cadherin methylation in gastric mucosa from H. pylori-induced enlarged fold gastritis before and after H. pylori eradication. Moreover, we analyzed the mechanism of H. pylori infection-induced E-cadherin hypermethylation. Twenty-three H. pylori-positive patients with enlarged folds, 18 H. pylori-positive and seven H. pylori-negative patients without enlarged folds, were involved in the study. E-cadherin promoter methylation was studied using quantitative methylation-specific polymerase chain reaction. We investigated methylation percentage and DNA methyltransferase activity in gastric cancer cell lines treated with EGF, TNFalpha, and MG132. E-cadherin methylation percentage of the gastric antral and body mucosa in H. pylori-positive patients with enlarged folds was much greater than that in both H. pylori-positive and -negative patients without enlarged folds. After H. pylori eradication, the methylation percentage in six patients with enlarged fold gastritis decreased significantly from 15.6 +/- 3.9 to 8.8 +/- 2.2 (p < .05). Moreover, the methylation was induced by TNFalpha, MG132, and EGF treatment, and DNA methyltransferase activity was induced by EGF treatment in MKN-1 cells. Our findings suggest that the hypermethylation of E-cadherin promoter might be involved in the process of gastric carcinoma through the specialized factors in H. pylori-induced enlarged fold gastritis.

IS HELICOBACTER PYLORI‐INDUCED ENLARGED FOLD GASTRITIS A HIGH‐RISK FACTOR FOR GASTRIC CARCINOMA?

It is now a generally accepted fact that Helicobacter pylori is an important cause of gastric carcinoma. The International Agency for Research on Cancer classified H. pylori as a group 1 carcinogen. We previously reported that H. pylori‐positive subjects had enlarged folds (fold width = 5 mm); that is, ‘enlarged fold gastritis’. Helicobacter pylori‐induced enlarged fold gastritis is accompanied by a massive infiltration of inflammatory cells, profound production of interleukin‐1β (IL‐1β) and hepatocyte growth factor (HGF), which decrease gastric acid secretion and increase the proliferation rate of the gastric epithelial cells. In addition, there is increased mutagenicity of gastric juice, and mucosal 8‐hydroxydeoxyguanosine (8‐OhdG) levels. Fold width improves and these factors recover to within a normal range with the eradication of H. pylori. The odds ratio for gastric carcinoma and the prevalence of diffuse‐type early gastric carcinoma in the body region increased with an increase in fold width. Therefore, enlarged fold gastritis may be a major risk factor for gastric carcinoma among H. pylori‐infected people. We propose that H. pylori‐infected persons with enlarged fold gastritis are a potential population for the prevention of gastric carcinoma via the use of antibiotics.

Helicobacter pylori-induced enlarged-fold gastritis is associated with increased mutagenicity of gastric juice, increased oxidative DNA damage, and an increased risk of gastric carcinoma.

The severe inflammation, increased cell proliferation and marked acid inhibition observed in subjects with Helicobacter pylori-associated enlarged-fold gastritis suggest that enlarged-fold gastritis may be a risk factor for gastric carcinoma. The purpose of the present study was to determine whether a relationship exists between enlarged-fold gastritis and gastric carcinoma. One hundred and thirty-five H. pylori-positive patients with early gastric carcinoma and 141 age- and sex-matched H. pylori-positive controls without gastric carcinoma were involved in the study. The widths of gastric body folds were measured by double-contrast radiographs. The mutagenicity of gastric juice was assayed using the Ames test and Salmonella typhimurium TA-98 or TA-100 with S9-mix. Levels of 8-hydroxydeoxyguanosine (8-OHdG) in gastric mucosa were examined using high-performance liquid chromatographic-electrochemical detection. An upward shift in the distribution of gastric fold widths in H. pylori-positive patients with early gastric carcinoma was found. Enlarged-fold gastritis (fold width >/=5 mm) was observed in 81% of the patients with gastric carcinoma, compared with 46% of H. pylori-positive controls. The odds ratio for gastric carcinoma increased with increasing fold width to a maximum of 35.5 in persons with fold width >/=7 mm. The prevalence of diffuse-type early gastric carcinoma in the body region increased with increasing fold width. The mutagenicity of gastric juice from the patients with enlarged-fold gastritis was significantly higher than that in H. pylori-negative controls and H. pylori-positive patients without enlarged folds. Mucosal 8-OHdG levels in the body region of patients with enlarged-fold gastritis were significantly higher than in H. pylori-negative controls and H. pylori-positive patients without enlarged-fold gastritis. Eradication of H. pylori significantly decreased the mutagenicity of gastric juice and 8-OHdG levels in the gastric mucosa from patients with enlarged-fold gastritis. A significant association is suggested between enlarged-fold gastritis and gastric carcinoma.

Morphological and functional restoration of parietal cells inHelicobacter pylori associated enlarged fold gastritis after eradication

BACKGROUND/AIMHelicobacter pylori infections are associated with hypochlorhydria in patients with pangastritis. It has previously been shown that eradication of H pylori leads to an increase in acid secretion in H...

High prevalence of serum immunoglobulin G antibody to Helicobacter pylori and raised serum gastrin and pepsinogen levels in enlarged fold gastritis.

To clarify the prevalence of Helicobacter pylori infection in enlarged fold gastritis, serum immunoglobulin (Ig) G antibody to H pylori was determined in 19 patients with severely enlarged gastric body folds (the widest fold greater than 10 mm on the radiograph), 55 patients with moderately enlarged folds (6 to 10 mm) and 44 control subjects (5 mm or less). The prevalence of serum IgG antibody to H pylori in the severe (100%) and moderate groups (100%) was significantly higher than that in controls (34.1%) (P < 0.01). There were significant differences among the three groups in serum gastrin, pepsinogen I and pepsinogen II levels (severe had the highest levels, followed by moderate and then controls, P < 0.001). H pylori colonization in the gastric mucosa was confirmed by culture, urease test or both, and inflammation by hematoxylin and eosin stain in the 25 H pylori seropositive patients who underwent endoscopy and biopsy. Results suggest that H pylori infection is highly prevalent in enlarged fold gastritis. Further studies on enlarged fold gastritis and H pylori infection are needed.

Increased production of interleukin 1 beta and hepatocyte growth factor may contribute to foveolar hyperplasia in enlarged fold gastritis.

It has been reported that eradication of Helicobacter pylori improves fold width in H pylori associated enlarged fold gastritis. The aim of this study was to clarify the mechanism of fold thickening in this condition. In eight patients with enlarged fold gastritis and 13 patients without enlarged folds, the presence of H pylori infection, inflammatory infiltrates, mucosal plasia, and epithelial cell proliferation in the body mucosa were investigated, and production of transforming growth factor alpha (TGF alpha), hepatocyte growth factor (HGF), and interleukin 1 beta (IL 1 beta) was determined by a competitive reverse transcription/polymerase chain reaction method and in vitro short-term culture of biopsy specimens. In the patients with enlarged fold gastritis, inflammatory infiltrates including macrophages increased with H pylori colonisation in the body. Foveolar thickness and proliferating cell nuclear antigen (PCNA) labelling index were increased. Messenger RNA levels of HGF, but not TGF alpha, were increased, and release of HGF and IL 1 beta was increased. HGF release, which was positively correlated with IL 1 beta release and foveolar thickness, decreased in the presence of IL 1 receptor antagonist. After eradication of H pylori, inflammatory infiltrates, IL 1 beta and HGF release decreased with concomitant decreases in PCNA labelling index, foveolar thickness and fold width. Increased IL 1 beta and HGF production caused by H pylori infection may contribute to fold thickening of the stomach by stimulating epithelial cell proliferation and foveolar hyperplasia in patients with enlarged fold gastritis.

Increased fundic mucosal interleukin-1β and hepatocyte growth factor release in H. pylori associated enlarged fold gastritis

Increased fundic mucosal interleukin-1β and hepatocyte growth factor release in H. pylori associated enlarged fold gastritis

Improved fold width and increased acid secretion after eradication of the organism in Helicobacter pylori associated enlarged fold gastritis.

This study examined the effects of eradication of Helicobacter pylori (H pylori) infection on gastric mucosal morphology and acid secretion. Sixteen H pylori positive patients with enlarged gastric body folds were divided into two groups: (a) patients with moderate enlargement (fold width: 6 to 10 mm, n = 8) and (b) patients with severe enlargement (> 10 mm, n = 8). After successful treatment, gastric body fold width was reduced in both groups (p < 0.01) with an associated decrease in inflammatory infiltrates in the body mucosa (p < 0.01 and p < 0.05). Basal acid output and tetragastrin stimulated maximal acid output (mean (SEM)) in all 16 patients significantly increased from 1.1 (0.5) to 2.9 (0.9) mmol/h (p < 0.05) and from 5.4 (1.3) to 18.7 (2.3) mmol/h (p < 0.01), respectively, with a significant decrease in fasting serum gastrin concentrations, from 127.1 (16.1) to 59.6 (3.8) pg/ml (p < 0.01). The increase in acid secretion after eradication of H pylori was more noticeable in the severe group, who had shown lower acid secretion and higher serum gastrin concentrations (p < 0.05) before eradication, than the increase seen in the moderate group. The decreases in ammonia nitrogen content seen after eradication were significant in basal (from 0.91 (0.17) to 0.37 (0.08) mmol/h, p < 0.05) and stimulated gastric secretions (from 1.57 (0.19) to 0.37 (0.13) mmol/h, p < 0.01), although these changes were too small to explain the increases in basal acid output and maximal acid output. These results suggest that inflammation of the gastric body mucosa caused by H pylori infection is associated with enlarged gastric body folds and inhibition of acid secretion in H pylori positive patients with enlarged gastric body folds.