Predominant mucosal IL-8 mRNA expression in non-cagA Thais is risk for gastric cancer

AIM:To study gastric mucosal interleukine-8(IL-8) mRNA expression,the cytotoxin-associated gene A(cagA) mutation,and serum pepsinogen(PG)Ⅰ/Ⅱ ratio related risk in Thai gastric cancer.METHODS:There were consent 134 Thai non-cancer volunteers who underwent endoscopic narrow band imaging examination,and 86 Thais advance gastric cancer patients who underwent endoscopic mucosal biopsies and gastric surgery.Tissue samples were taken by endoscopy with 3 points biopsies.The serum PG Ⅰ,Ⅱ,and Helicobacter pylori(H.pylori) immunoglobulin G(IgG) antibody for H.pylori were tested by enzyme-linked immunosorbent assay technique.The histopathology description of gastric cancer and non-cancer with H.pylori detection was defined with modified Sydney Score System.Gastric mucosal tissue H.pylori DNA was extracted and genotyped for cagA mutation.Tissue IL-8 and cyclooxygenase-2(COX-2) mRNA expression were conducted by real time relative quantitation polymerase chain reaction.From 17 Japanese advance gastric cancer and 12 benign gastric tissue samples,all were tested for genetic expression with same methods as well as Thai gastric mucosal tissue samples.The multivariate analysis was used for the risk study.Correlation and standardized t-test were done for quantitative data,P value < 0.05 was considered as a statistically significant.RESULTS:There is a high non cagA gene of 86.8 per cent in Thai gastric cancer although there are high yields of the East Asian type in the positive cagA.The H.pylori infection prevalence in this study is reported by combined histopathology and H.pylori IgG antibody test with 77.1% and 97.4% of sensitivity and specificity,respectively.The serum PG Ⅰ/Ⅱ ratio in gastric cancer is significantly lower than in the non-cancer group,P = 0.045.The serum PG Ⅰ/Ⅱ ratio of less than 3.0 and IL-8 mRNA expression ≥ 100 or log 10 ≥ 2 are significant cut off risk differences between Thai cancer and non-cancer,P = 0.03 and P < 0.001,respectively.There is a significantly lower PGI/II ratio in Japanese than that in Thai gastric cancer,P = 0.026.Serum PG Ⅰ/Ⅱ ratio at cut off less than 3.0 and IL-8 mRNA expression Raw RQ > 100 or log 10 > 2 are significantly difference between Thai cancer group when compared to non-cancer group,P = 0.013 and P < 0.001,respectively.In the correlation study,low PG Ⅰ/Ⅱ ratio does not associate with chronic atrophic gastritis severity score in Thais non-cancer cases.However,there is a trend,but not significant convert correlation between IL-8 mRNA expression level and low PG Ⅰ/Ⅱ ratio in Thai positive H.pylori infection.The high expression of IL-8 gene demonstrates a poorer prognosis by stage and histology.CONCLUSION:Predominant gastric mucosal IL-8 mRNA expression level,H.pylori infection,and low PG Ⅰ/Ⅱ ratio are relative risks for Thai gastric cancer without correlation with cagA mutation.

Comparison of He/icobacter py/ori infection and gastric mucosal histological features of gastric ulcer patients with chronic gastritis patients

AIM: To compare Helicobacter pyloriinfection and gastric mucosal histological features of gastric ulcer patients with chronic gastritis patients in different age groups and from different biopsy sites.METHODS: The biopsy specimens were taken from the antrum, corpus and upper angulus of gastric ulcer and chronic gastritis patients. Giemsa staining, improved Toluidine-blue staining and H pylori-specific antibody immune staining were performed as appropriate for the histological diagnosis of H pylori infection. Hematoxylineosin staining was used for the histological diagnosis of activity of H pylori infection, mucosal inflammation,glandular atrophy and intestinal metaplasia and scored into four grades according to the Updated Sydney System.RESULTS: Total rate of H pylori infection, mucosal inflammation, activity of H pylori infection, glandular atrophy and intestinal metaplasia in 3 839 gastric ulcer patients (78.5%, 97.4%, 82.1%, 61.1% and 64.2%,respectively) were significantly higher than those in 4 102chronic gastritis patients (55.0%, 90.3%, 56.2%, 36.8%,and 37.0%, respectively, P＜0.05). The rate of H pylori colonization of chronic gastritis in ＜30 years, 31-40 years,41-50 years, 51-60 years, 61-70 years and ＞70 years age groups in antrum was 33.3%, 41.7%, 53.6%, 57.3%,50.7%, 43.5%, respectively; in corpus, it was 32.6%,41.9%, 53.8%, 60.2%, 58.0%, 54.8%, respectively; in angulus, it was 32.4%, 42.1%, 51.6%, 54.5%, 49.7%,43.5%, respectively. The rate of Hpyloricolonization of gastric ulcer in ＜30 years, 31-40 years, 41-50 years,51-60 years, 61-70 years and ＞70 years age groups in antrum was 60.5%, 79.9%, 80.9%, 66.8%, 59.6%, 45.6%,respectively; in corpus, it was 59.7%, 79.6%, 83.6%,80.1%, 70.6%, 59.1%, respectively; in angulus, it was61.3%, 77.8%, 75.3%, 68.8%, 59.7%, 45.8%,respectively. The rate of H pylori colonization at antrum was similar to corpus and angulus in patients, below50 years, with chronic gastritis and in patients, below40 years, with gastric ulcer. In the other age- groups,the rate of H pylori colonization was highest in corpus,lower in antrum and lowest in angulus (all P＜0.05). The rates of glandular atrophy and intestinal metaplasia were higher and earlier in H pylori-positive patients than those without H pylori infection (both P＜0.01). In comparison of gastric ulcer patients with chronic gastritis patients,the rate of glandular atrophy and intestinal metaplasia was higher in H pylori-positive patients with gastric ulcer than in H pylori-positive patients with chronic gastritis(both P＜0.01); the rate of glandular atrophy and intestinal metaplasia were also higher in H pylori-negative patients with gastric ulcer than in H pylori-negative patients with chronic gastritis (both P＜0.01). Both glandular atrophy and intestinal metaplasia were much more commonly identified in the angulus than in the antrum, lowest in corpus (all P＜0.01).CONCLUSION: Rate of H pylori infection, glandular atrophy and intestinal metaplasia in gastric ulcer were higher than in chronic gastritis in all-different age -groups. Distribution of H pylori colonization is pangastric in the younger patients. It is highest in corpus, lower in antrum and lowest in angulus in the older age groups. Progression of glandular atrophy and intestinal metaplasia seem to have a key role in the distribution of H pylori colonization. H pylori appears to be the most important risk factor for the development of glandular atrophy and intestinal metaplasia, but it is not the only risk.

Gastric mucosa in Mongolian and Japanese patients with gastric cancer and Helicobacter pylori infection

AIM: To investigate the characteristics of gastric cancer and gastric mucosa in a Mongolian populationby comparison with a Japanese population.METHODS: A total of 484 Mongolian patients with gastric cancer were enrolled to study gastric cancer characteristics in Mongolians. In addition, a total of 208 Mongolian and 3205 Japanese consecutive outpatients who underwent endoscopy, had abdominal complaints, no history of gastric operation or Helicobacter pylori eradication treatment, and no use of gastric secretion inhibitors such as histamine H2-receptor antagonists or proton pump inhibitors were enrolled. This study was conducted with the approval of the ethics committees of all hospitals. The triple-site biopsy method was used for the histologic diagnosis of gastritis and H. pylori infection in all Mongolian and Japanese cases. The infection rate of H. pylori and the status of gastric mucosa in H. pylori-infected patients were compared between Mongolian and Japanese subjects. Age(± 5 years), sex, and endoscopic diagnosis were matched between the two countries.RESULTS: Approximately 70% of Mongolian patients with gastric cancer were 50-79 years of age, and approximately half of the cancers were located in the upper part of the stomach. Histologically, 65.7% of early cancers exhibited differentiated adenocarcinoma, where as 73.9 % of advanced can cersdisplayed undifferentiated adenocarcinoma. The infection rate of H. pylori was higher in Mongolian than Japanese patients(75.9% vs 4 8. 3 %, P<0.0001). When stratified by age, the prevalence was highest among young patients, and tended to decrease in patients aged 50 years or older. The anti-East-Asian Cag Aspecific antibody was negative in 99.4% of H. pyloripositive Mongolian patients. Chronic inflammation, neutrophil activity, glandular atrophy, and intestinal metaplasia scores were significantly lower in Mongolian compared to Japanese H. pylori-positive patients(P < 0.0001), with the exception of the intestinal metaplasia score of specimen from the greater curvature of the upper body. The type of gastritis changed from antrumpredominant gastritis to corpus-predominant gastritis with age in both populations.CONCLUSION: Gastric cancer was located in the upper part of the stomach in half of the Mongolian patients; Mongolian patients were infected with non-East-Asiantype H. pylori.