- Email: [email protected]
S1608 Coexisting Gastric Cancer and Duodenal Ulcer: Distrubution of Atrophic Gastritis and Intestinal Metaplasia
infection or hypoxia dose-dependently induce HIF-1α in AGS. H. pylori-induced activation of HIF-1α involved formation of a complex consisting of APE-1/Ref-1 and a coactivator p300. H. pylori infection increased Mcl-1 and Noxa promoter activity and Mcl-1S and Noxa protein expression in AGS, effects that were inhibited by pretreatment with echinomycin. After H. pylori infection greater Mcl-1S and Noxa expression was observed in shRNA compared to pSIREN. Conclusion: Our results indicate that APE-1/Ref-1 enhances expression and activity of HIF-1α in H. pylori-infected gastric epithelial cells. H. pylori infection resulted in increased expression of apoptotic Mcl-1S or Noxa proteins in cells with reduced level of APE-1/Ref-1. These novel results further implicate APE-1/Ref-1's role in mediating the effects of H. pylori infection in gastric epithelial cells and potentially determining the outcome of infection. (Supported by R01 DK61769)
S1606
Aim To investigate the changes of incidence of gastric cancer and the changes of pathology in gastric mucosa during the 10 years after Helicobacter.pylori(H. pylori) eradication among the Hp-positive subjects in the region with high gastric cancer incidence in China. Methods One thousand and six individuals (age from 35 to 75 years old) were randomly selected in Yantai, Shandong province,China. Five hundred and fifty two individuals with H. pylori infection were randomly divided into treatment group(T group) (276) and placebo group(P group )(276).T group received OAC triple therapy for one week, and P group served as control.Follow-up study was carried out with endoscopy in the 2nd,5th,8th and 10th year respectively. We compared pathology of the biopsy specimens from the same sites during the every visit. Statistical analysis was done by the life table analysis and T test. Results During the 10 years,two and seven individuals with gastric cancer were cumulative in the T group and P group respectively, we have compared the incidence of gastric cancer between the 2 groups by the life table analysis, the cumulative incidence of gastric cancer was not significantly different between the T and P groups during the ten-year observation (P= 0.13).The analysis of independent samples T test of pathology between 2 groups at the 10th year were as follow:compared with that in P group,Corpus specimens in T group showed significantly decreased mean score in gastric atrophy( 0.27±0.68 VS 0.54±0.99,P=0.01).compared with that in P group,Corpus and antral specimens in T group showed significantly decreased mean score in polymorphonuclear infiltration(0.32±0.59 vs 0.90±0.71,p<0.001. 0.49±0.81 vs 1.24±0.84,p<0.001,respectively),and mean score in lymphocytic infiltration significantly decreased(0.22±0.41 vs 0.37±0.48,p=0.01. 0.20±0.40 vs 0.54±0.50,p<0.001,respectively). Conclusions: H. pylori eradication could improve acute gastritis and lymphocytic infiltration.H. pylori eradication could delay progression of atrophy in corpus. H. pylori eradication had the tendency to lower the incidence of gastric cancer development.
S1604 Helicobacter felis Infection Modulates Gastric Sonic Hedgehog Expression and Signaling Meghna Waghray, Juanita L. Merchant Background: Helicobacter-mediated gastritis induces oxyntic gland atrophy, a lesion that predisposes the stomach to cancer. However, the mechanism by which chronic inflammation triggers loss of the parietal cells is not understood. We hypothesize that changes in gastric cell differentiation might play a role in the development of gastric atrophy. As such, the developmental peptide Sonic hedgehog (Shh) has recently been implicated as an essential factor in gastric organogenesis, gland differentiation and regulation of H,K-ATPase. In addition, studies performed in humans and rodents have revealed that Shh expression is lost in Helicobacter-induced gastric atrophy. Objective: We hypothesize that Helicobacter infection directly affects loss of Shh in the parietal cell and hastens gastric atrophy. We tested this hypothesis by infecting LacZ reporter mice with H. felis to identify the cells that produce and respond to Shh. Methods: Shh-LacZ and Gli1-LacZ reporter mice were infected with H.felis for 3 and 8 weeks. Sections from infected mice were co-stained using X-gal to detect beta galactosidase enzyme levels (b-Gal) with either GSII lectin or H+,K+-ATPase and antialpha smooth muscle actin (SMA) antibodies. Results: In the Shh-LacZ mice, all the major cell types expressed Shh including parietal, chief and surface pit cells. The highest expression was observed in the parietal and chief cells. However, there was essentially no expression in the antrum. With chronic inflammation after both 3 and 8 weeks of infection, there was loss of Shh expression in the parietal and chief cells and an increase in expression in the mucous neck and surface pit cells. Infected Gli1-LacZ mice showed that many of the hedgehog (Hh) responsive cells were both LacZ and a-SMA positive stromal cells demonstrating that many of the responding cells were myofibroblasts. Moreover, the chronic inflammation resulted in a significant increase in Gli1 expression. These results were consistent with our In Vitro studies in which proinflammatory cytokines IL-1b and TNFa inhibited Shh expression in primary parietal cell cultures, but stimulated Shh expression in gastric cell lines expressing mucous cell markers. Conclusion: There are both qualitative and quantitative differences in Shh expression in the stomachs of Helicobacter infected compared to uninfected mice. The chronic inflammation resulted in a shift in Shh expression from oxyntic-peptic cell lineages to mucous cell types. Moreover, the shift correlated with higher Hh signaling activity in stromal cell types.
S1607 Earlier H. pylori Eradication Restores Sonic Hedgehog (Shh) Expression in the Gastric Mucosa Toshihiro Nishizawa, Hidekazu Suzuki, Etsuko Sugai, Izumi Nakagawa, Tatsuhiro Masaoka, Eisuke Iwasaki, Yoshimasa Saito, Toshifumi Hibi Background and Aim: Sonic hedgehog (Shh) is a morphogen involved in the homeostasis of the gastric fundic gland. Shh is soluble signal that is secreted in concentration gradients through a tissue and regulate epithelial cell differentiation. We have previously shown that disturbances of epithelial cell differentiation induced by H. pylori-associated gastritis in Mongolian gerbils are correlated closely with reduced Shh expression (J. Pathol. 206:186, 2005). The alteration of gastric mucosal Shh expression after eradication of H. pylori was examined. Material and Method: Male Mongolian gerbils were inoculated with H. pylori (ATCC43504) at the age of 5 weeks. As eradication treatment, a triple therapy with lansoprazole, amoxicillin and clarithromycin for two days was carried out at 12, 24 or 48 weeks after the inoculation. Gerbils were examined at 10 weeks after the eradication. Gastric inflammation was evaluated by the tissue myeloperoxidase (MPO) activity and by the histological scoring based upon the updated Sydney system. Immunohistochemistry against Shh and H+-K+-ATPase and the in situ hybridization of Shh were performed. Results: H. pylori eradication was confirmed by microaerobic bacterial culture. Shh mRNA expression was clearly localized in the fundic gland region with a gradient in the control and the eradicated gerbils. The MPO activity and scores for acute and chronic inflammation as well as atrophy in the H. pylori eradicated gerbils were significantly decreased compared with those of H. pylori positive, non-eradicated gerbils. The horizontal extension of the area positive for Shh and H+-K+-ATPase expression in the H. pylori eradicated gerbils, was significantly increased as compared with that of H. pylori positive, non-eradicated gerbils (p<0.01). The earlier eradication promoted the better restoration of Shh expression. The 50% of cohorts eradicated at 24 weeks and all cohorts eradicated at 48 weeks exhibited a heterotopic proliferative gland (HPG) which forms hyperplastic mucosa and mucin-containing cystic lesion at the lower gastric body. In the cohort with HPG, the front line of Shh regeneration was cut off at the point of HPG. Conclusion: After H. pylori eradication, sonic hedgehog expression was significantly restored and a significant improvement in gastric atrophy was observed. These results suggest that H. pylori-associated deregulation of Shh expression, that could be linked to gastric atrophy and its associated preneoplastic transformation, is reversible only after the earlier H. pylori eradication.
S1605 A Long-Term PPI Administration Induces Atrophic Corpus Gastritis and Promotes Development of Atypical Glands in Mongolian Gerbils Infected with Helicobacter pylori Tadashi Hagiwara, Ken-ichi Mukaisho, Hiroyuki Sugihara, Takanori Hattori Background: Long-term use of proton pump inhibitors (PPIs) has been reported to worsen corpus atrophic gastritis in patients with Helicobacter pylori (H. pylori) infection. The purpose of this study was to elucidate whether corpus atrophic gastritis is worsened after long-term administrations of PPI using Mongolian gerbils (MGs), which provide an excellent model for studying H. pylori related gastritis and adenocarcinoma . Methods: MGs were separated into 4 groups (n = 5). H. pylori (ATCC43504) was inoculated into groups A and B, PPI was administered to groups A and C, and group D that received no treatment was a control. MGs had access to food containing omeprazole (100 mg/kg body weight/day) for 6 months, according to the recently established protocol (Hagiwara T, et al. Dig Dis Sci, 2007). PPI was administered 6 months after the infection, when pangastritis developed in the infected MGs in. The stomach was removed and cut into 9 sections (6 in fundus and 3 in antrum). We evaluated corpus atrophy using the score of no parietal cells in 6 sections of fundus. First, we calculated a ratio of the area of no parietal cells in each section using hematoxylin and eosin staining, and then we added the ratio of 6 sections. In one animal, the full score was 600, because it had 6 sections in fundus and a full score of one section was defined as 100%. We defined the submucosal gland without atypia as a heterotopic gland, and the submucosal mucinous gland with nuclear and structural atypia as an atypical mucinous gland. Results: Microscopically, more severe neutrophilic and lymphoid infiltrates were detected in group A than in the other groups. There were no atrophic changes in groups C and D. The score of corpus atrophy in group A (317 ± 17.9; mean ± SE) was significantly higher than that in group B (P < 0.0048: student's t-test). Heterotopic glands were found in groups A (5 out of 5) and B (4 out of 5). Atypical mucinous glands were only detected in 3 out of 5 (60%) in group A. Discussion: The scores of corpus atrophy in group A were significantly higher than those in the other groups. Moreover, atypical mucinous glands, which were interpreted as adenocarcinoma in previous studies, were developed in 60% of group A. In general, these atypical mucinous glands are developed in less than 10% at 18 to 24 months after the infection. These findings suggest that long-term administration of PPI induces development of atypical mucinous glands, associated with the progression of atrophic corpus gastritis in MGs infected with H. pylori.
S1608 Coexisting Gastric Cancer and Duodenal Ulcer: Distrubution of Atrophic Gastritis and Intestinal Metaplasia Soo-Jeong Cho, Il Ju Choi, Chan Gyoo Kim, Jong Yeul Lee, Myeong-Cherl Kook Background/Aims: A strong correlation exists between atrophic gastritis/intestinal metaplasia and gastric cancer. Duodenal ulcer (DU) disease characteristically has an antral predominant gastritis and a lower risk for gastric cancer (GC). The aim of this study was to evaluate underlying atrophy and intestinal metaplasia in patients with gastric cancer in the absence or presence of duodenal ulcer. Patients and Methods: A total of 914 patients with stomach cancer or duodenal ulcer were prospectively enrolled between August 2006 and June 2007. The patients were divided into 3 groups; group A: patients with only GC, group B: patients with only DU, and group C: patients with both GC and DU. Underlying gastric histology was evaluated using updated Sydney system at antrum lesser curvature, upper body lesser curvature (UBLC) and upper body greater curvature (UBGC). Helicobacter pylori (H. pylori) was determined by histology and rapid urease test. Comparison of histological grades of each group were analyzed using the Kruskal-Wallis method. Results: The numbers of patients of group A, B, and C were 808, 57, and 50. The coexisting GC and DU patients observed in 5.7% (50/858). Mean ages of three groups were 58, 52, and 54 years, respectively (p=
A-233
AGA Abstracts
AGA Abstracts
Ten-Year Follow-Up Study On the Incidence of Gastric Cancer and the Pathological Changes of Gastric Mucosa After H. pylori Eradication in China Liya Zhou
AGA Abstracts
0.005). There was no difference in the male to female ratio and in positivity for H. pylori test among the three groups (p=0.509 and 0.694). No differences were not found in the histological differentiation and tumor stages between group A and C (p=0.370 and 0.238). Stages of duodenal ulcer in group B and C did not show any difference between group B and C (p=0.779). Mean scores of atrophy and intestinal metaplasia of group C at antrum were 1.91±0.88 and 1.51±1.18, which were similar with those of group A (1.86±1.13 and 1.46±1.22) and were significantly higher than those of group B (1.35±0.85 and 0.74±0.89) (p=0.004 and <0.001). Mean scores of atrophy and intestinal metaplasia of group C at UBLC were 0.87±1.26 and 0.79±1.06, which were lower than those of group A (1.62±1.30 and 1.39±1.22) and were higher than those of group B (0.22±0.71 and 0.16±0.54) (p<0.001 and <0.001). Conclusion: DU is not rare in GC patients. Even in DU patients, those with more severe atrophy and intestinal metaplasia at corpus as well as at antrum may have a higher risk for the development of gastric cancer.
S1611 Effect of H. pylori Infection On Expression of TFF2 in Rhesus Monkeys Matthew Goldman, Cristina Semino-Mora, Arifur Rahman, Hui Liu, Wilfred De La Cruz, Carolyn A. Sullivan, Andre Dubois Background: The trefoil peptides are proteins important in mucosal defense and repair. TFF2, in particular, plays a crucial role in the process of mucosal healing. H. pylori causes peptic ulcer disease and gastric cancer, and has been found to modify TFF2 expression. However, there is little information regarding TFF2 expression during the course of the natural history of gastric disease. Methods: In order to simulate a clinical situation, we investigated the effect of H. pylori infection on the expression of TFF2 in 23 Rhesus monkeys by performing gastroscopies with gastric biopsies. The monkeys were divided into four groups: controls (C), H. pylori infected (H), ethyl-nitro-nitrosoguanidine (ENNG), and H. pylori + ENNG (HE). H. pylori infection was confirmed by histology, culture, and RTPCR. TFF2 expression was determined by immunohistochemistry (IHC) using an anti-TFF2 polyclonal antibody and by in situ hybridization (ISH) using a probe specific for rhesus monkey TFF2. Quantification was performed using a semi-automated computer program and the MATLAB platform. Results: After 5 years of ENNG administration, gastric antral biopsies of these three HE monkeys showed focal intestinal metaplasia with epithelial hyperplasia. One of these animals was found to have developed high grade dysplasia in an antral polyp. TFF2 expression trended towards an increase in H and HE monkeys over the control group. However, at 60-months, the HE monkeys with dysplasia had lower TFF2 expression compared to the other HE animals, but the difference was not statistically significant (dysplasia: 0.28 ± 8%, no dysplasia: 0.36 ± 2%). Discussion: Long-term, persistent, H. pylori infection is associated with a trend towards an increase in TFF2 expression, but this increase is curbed as precancerous lesions appear. The decreased TFF2 expression seen in monkeys with dysplasia supports the role of TFF2 in mucosal protection, suggesting that decreased expression may serve as an early indicator of neoplasia. These observations suggest that dysplasia may develop as TFF2 expression falters during prolonged gastritis.
S1609 Clinical Evaluation of Helicobacter pylori Tyrosine-Phosphorylated CagA in Diffuse-Type Gastric Cancer Patients: A Case-Control Study Yoshihiro Wada, Masanori Ito, Shunsuke Takata, Shosuke Kitamura, Akemi Takamura, Masana Tatsugami, Shinobu Imagawa, Yoshiaki Matsumoto, Shinji Tanaka, Masaharu Yoshihara, Kazuaki Chayama Background: Cytotoxin-associated antigen A (CagA) protein produced by Helicobacter pylori (H. pylori) is proposed to be associated with the pathogenicity of gastric carcinogenesis. CagA is translocated into the gastric epithelial cells and localizes to the inner surface of the plasma membrane, where it undergoes tyrosine phosphorylation at the Glu-Pro-Ile-Tyr-Ala (EPIYA) motif. East Asian CagA has stronger toxicity than Western CagA, and the third domain of the EPIYA motif of East Asian CagA (D site) plays critical role in abnormal intracellular signals, leading to carcinogenesis. Aim: To investigate the pathogenesis of tyrosinephosphorylated CagA in diffuse-type gastric cancer (DGC). Methods: We examined 27 DGC patients (group-DGC; 13 men, mean age 56.9 y.o.) and age-, gender-matched 27 patients with atrophic gastritis (group-AG) as controls. All patients were diagnosed as H. pyloripositive. All DGC patients received endoscopic mucosal resection and histological diagnosis was confirmed. Biopsy specimens (from the antrum and the corpus) and fasting sera were collected from all patients. The grade of histological gastritis (according to the updated Sydney System) and the serum markers of gastritis (pepsinogens and gastrin) were determined. We synthesized 10 mer oligopeptide with tyrosine phosphorylation (CEPIY(P)ATIDF; CagA-P) designed from East Asian CagA-specific EPIYA-D site (Higashi et al. Proc Natl Acad Sci, 2002) as an antigen and originally generated a polyclonal antibody. The expression of CagAP was evaluated by Western blotting and immunohistochemistry. Moreover, serum titers of anti-CagA-P antibody were determined by enzyme linked immunosorbent assay test (Takata S et al. AGA, 2007) using the compounded oligopeptide as a solid phase of an antigen. Results: There was no difference in histological gastritis and in classical serum markers between the two groups. Immunohistochemically, the expressions of CagA-P were detected in the cytoplasm of the surface epithelium. In the corpus specimens, we found statistically higher expressions of CagA-P in group-DGC than those of group-AG (P=0.035). Moreover, the serum titers of anti-CagA-P antibody were significantly higher in group-DGC than those of group-AG (P=0.031). Eleven patients in group-DGC (11/27, 41%) showed both positive expression of CagA-P and high titer of anti-CagA-P antibody, and its prevalence was statistically higher than that of group-AG (5/27, 19%; P=0.014). Conclusions: CagA-P plays an important role in gastric carcinogenesis, especially in DGC. Clinical quantification of antiCagA-P antibody may be useful for the evaluation of DGC risk.
S1612 Helicobacter pylori Infection Diminish the IFN-γ Secretion By T Lymphocytes in Response to Stimulation with Different Agents in Children Czkwianianc Elzbieta, Wieslawa Rudnicka, Magdalena Chmiela, Ewa Malecka-Panas Despite generating an inflammatory response to Helicobacter pylori (H. pylori) infection, the immune system usually fails to clear the bacteria. Humoral response induced by H. pylori has no role in the eradication, cellular response depending on the type of T-lymphocytes(Th1 or Th2) cells infiltrating gastric mucosa, may be more harmful than beneficial to the host. The aim of the study was the investigation of cellular response to H. pylori infection in children. Material and methods. In Vivo study: 53 consecutive dyspeptic children aged 617y with chronic dyspeptic symptoms underwent upper GI endoscopy with gastric biopsy. Endoscopy lesions and pathology scoring with upgraded Sydney System in the biopsies were estimated as well as H. pylori infection status by pathology and urease test (UT). Blood sample from all examined children was taken to determine sera IgG-antibodies with ELISA test, sera IgG-antibodies to antigen cagA with ELISA test and to obtain peripheral blood mononuclear leucocytes (PBML). In Vitro study: Peripheral blood mononuclear leucocytes (PBML) were isolated from the blood for culture and examine the cell ability to secrete IFNγ after stimulate them with different factors: H. pylori heated rods and H. pylori heated rods in the interleukin 2 (IL2) milieu as well as with Il2 alone. Enumerated level of IFN-g concentration in the supernatant of the PBMC culture received as a difference between those two last above mentioned results. Results: 23 of all examined children (group I) were H. pylori infected (positive UT, pathology and serology) and 30 were not. Among them 14 children (group II) were H. pylori positive in serology at very low titres and 16 (group III) were serological negative. There was no endoscopic, histological and IFN-γ production differences between the group II and III. PBML from H. pylori infected children responded to H. pylori bacteria by IFN-γ production to a lower degree of concentration then in PBML from not infected patients (419±1041.9 ng/ml and 1642.2±2509.9 ng/ml,p<0.05). A week, but positive and significant statistically correlation between IFN-γ and chronic gastritis degree in the children H. pylori(+) (R=0.4603, p=0.03) was found. Strong and statistically significant correlation between anti-CagA-Ab and gastric glands atrophy in the children H. pylori(+) was seen (R=0.6406, p=0.007). Conclusions: H. pylori has weakened the cellular response to the infection what may favour the long lasting gastric colonization and the bacterial induced epithelial damage. In addition to weakening of cellular response to the infection, IFN-γ causes gastric mucosal damage in children.
S1610 Effects of Helicobacter pylori-Secreting Protein Tip α On the Human Gastric Epithelial Cell GES-1 Shi R. Hua, Ping Cheng, Hongjie Zhang Aims: To investigate the effects of tumor necrosis factor-α-inducing protein (Tip α) from H. pylori on human gastric epithelial cell line GES-1. Methods: The Tip α gene located in HP0596 was extracted from genome sequence of H. pylori strain 26695 and its open reading frame (ORF) was cloned into the eukaryotic expressing vector pcDNA3.1. Recombinant pcDNA3.1-Tipα and empty plasmid pcDNA3.1 were transfected into GES-1 cells by using the lipofectomine 2000, and the G418-resistent clones were screened. Normal GES-1 cells and with empty vector pcDNA3.1 were used as the control groups. The influences of Tip α protein on the cells proliferation, apoptosis, cell cycles by MTT assay and Flow Cytometry concentration of TNF-α, IL-1β, IL-8 were examined by ELISA, and expression of Bcl-2 and P53 gene were determined by Western Blot. Results: 1. The growth curve showed that the growth of Tip α gene transfected cells was faster, compared with control groups.2.Cell cycle analyzed by flow cytometry showed an increase in the proportion of the S-phase in the Tip α gene transfected cells, but a decrease in the G1-phase, apoptosis rate was significant lower than that of the controls. 3. ELISA assay showed that the inner cell concentration of TNFα was 49.801±5.960, 48.215±5.620, 47.777±5.754 (pg/ml) in the Tip α transfected group, empty vector transfected group and normal GES-1 cell group respectively, and there was no significance in all groups(p>0.05), while the medium concentration was 41.744±0.424, 31.654±1.404, 30.234±0.908 (pg/ml) respectively, and there was significant difference between the transfected group and the control groups(p<0.05). ELISA assay also showed the inner and outer cell concentrations of IL-1β were 93.886±5.082, 74.267±9.606, 69.550±10.491 and 58.474±6.927, 32.573±3.823, 30.686±2.898(pg/ml) in the transfected group, empty vector group and GES-1 cell group respectively, and IL-8 were 69.130±9.249, 44.002±5.497, 37.756±10.742 and 191.348±1.169, 40.396±8.901, 38.197±6.991(pg/ml) in the transfected group, empty vector group and GES-1 cell group respectively. The concentrations of IL-1β and IL-8 in the transfected group were higher than that in controls (p<0.05). 4. Expression of Bcl-2 gene in the transfected cells was up-regulated, while expression of P53 gene was suppressed.
AGA Abstracts
S1613 Role of Free Radical and Mucus in Rat Experimental Model of Gastritis with Ammonia; Combined Effect of Anti-Ulcer Agent Geranylgeranylacetone Eiji Umegaki, Takao Noguchi, Keishi Kojima, Nanako Shiraishi, Toshihisa Takeuchi, Satoshi Tokioka, Yukiko Yoda, Nozomi Takeuchi, Chikako Eiraku, Kazuhide Higuchi Background and aim: There are reports that Helicobacter pylori degrades mucin and undermines gastric mucosal integrity. On the other hand, there are reports that mucin acts as free radical scavengers in gastric mucosa. In this study, we used the rat experimental model of gastritis with ammonia and assessed the effects of ammonia on the gastric mucosa and gastric mucus, and whether free radicals are involved in the induction of gastric mucosal lesions. In addition, we evaluated the effect of novel anti-ulcer agent geranylgeranylacetone (GGA). Materials and methods: Male Wistar rats were used and sacrificed 6 weeks after the beginning of the study. Gastric mucosal injury was induced by giving 0.1% ammonia water ad libitum for 6 weeks. Group A; Water was offered ad libitum for 6 weeks. Group B; 0.1% ammonia water was offered ad libitum for 6 weeks. Group C; 0.1% ammonia water ad libitum and 200 mg/kg/day of GGA were administrated orally for 6 weeks. The tissue sections of removed stomach were prepared to measure the thickness of gastric mucosa and to stain superficial mucus by PAS and deep mucus by concanavalin A. The quantity of each positive
A-234
S1606
Aim To investigate the changes of incidence of gastric cancer and the changes of pathology in gastric mucosa during the 10 years after Helicobacter.pylori(H. pylori) eradication among the Hp-positive subjects in the region with high gastric cancer incidence in China. Methods One thousand and six individuals (age from 35 to 75 years old) were randomly selected in Yantai, Shandong province,China. Five hundred and fifty two individuals with H. pylori infection were randomly divided into treatment group(T group) (276) and placebo group(P group )(276).T group received OAC triple therapy for one week, and P group served as control.Follow-up study was carried out with endoscopy in the 2nd,5th,8th and 10th year respectively. We compared pathology of the biopsy specimens from the same sites during the every visit. Statistical analysis was done by the life table analysis and T test. Results During the 10 years,two and seven individuals with gastric cancer were cumulative in the T group and P group respectively, we have compared the incidence of gastric cancer between the 2 groups by the life table analysis, the cumulative incidence of gastric cancer was not significantly different between the T and P groups during the ten-year observation (P= 0.13).The analysis of independent samples T test of pathology between 2 groups at the 10th year were as follow:compared with that in P group,Corpus specimens in T group showed significantly decreased mean score in gastric atrophy( 0.27±0.68 VS 0.54±0.99,P=0.01).compared with that in P group,Corpus and antral specimens in T group showed significantly decreased mean score in polymorphonuclear infiltration(0.32±0.59 vs 0.90±0.71,p<0.001. 0.49±0.81 vs 1.24±0.84,p<0.001,respectively),and mean score in lymphocytic infiltration significantly decreased(0.22±0.41 vs 0.37±0.48,p=0.01. 0.20±0.40 vs 0.54±0.50,p<0.001,respectively). Conclusions: H. pylori eradication could improve acute gastritis and lymphocytic infiltration.H. pylori eradication could delay progression of atrophy in corpus. H. pylori eradication had the tendency to lower the incidence of gastric cancer development.
S1604 Helicobacter felis Infection Modulates Gastric Sonic Hedgehog Expression and Signaling Meghna Waghray, Juanita L. Merchant Background: Helicobacter-mediated gastritis induces oxyntic gland atrophy, a lesion that predisposes the stomach to cancer. However, the mechanism by which chronic inflammation triggers loss of the parietal cells is not understood. We hypothesize that changes in gastric cell differentiation might play a role in the development of gastric atrophy. As such, the developmental peptide Sonic hedgehog (Shh) has recently been implicated as an essential factor in gastric organogenesis, gland differentiation and regulation of H,K-ATPase. In addition, studies performed in humans and rodents have revealed that Shh expression is lost in Helicobacter-induced gastric atrophy. Objective: We hypothesize that Helicobacter infection directly affects loss of Shh in the parietal cell and hastens gastric atrophy. We tested this hypothesis by infecting LacZ reporter mice with H. felis to identify the cells that produce and respond to Shh. Methods: Shh-LacZ and Gli1-LacZ reporter mice were infected with H.felis for 3 and 8 weeks. Sections from infected mice were co-stained using X-gal to detect beta galactosidase enzyme levels (b-Gal) with either GSII lectin or H+,K+-ATPase and antialpha smooth muscle actin (SMA) antibodies. Results: In the Shh-LacZ mice, all the major cell types expressed Shh including parietal, chief and surface pit cells. The highest expression was observed in the parietal and chief cells. However, there was essentially no expression in the antrum. With chronic inflammation after both 3 and 8 weeks of infection, there was loss of Shh expression in the parietal and chief cells and an increase in expression in the mucous neck and surface pit cells. Infected Gli1-LacZ mice showed that many of the hedgehog (Hh) responsive cells were both LacZ and a-SMA positive stromal cells demonstrating that many of the responding cells were myofibroblasts. Moreover, the chronic inflammation resulted in a significant increase in Gli1 expression. These results were consistent with our In Vitro studies in which proinflammatory cytokines IL-1b and TNFa inhibited Shh expression in primary parietal cell cultures, but stimulated Shh expression in gastric cell lines expressing mucous cell markers. Conclusion: There are both qualitative and quantitative differences in Shh expression in the stomachs of Helicobacter infected compared to uninfected mice. The chronic inflammation resulted in a shift in Shh expression from oxyntic-peptic cell lineages to mucous cell types. Moreover, the shift correlated with higher Hh signaling activity in stromal cell types.
S1607 Earlier H. pylori Eradication Restores Sonic Hedgehog (Shh) Expression in the Gastric Mucosa Toshihiro Nishizawa, Hidekazu Suzuki, Etsuko Sugai, Izumi Nakagawa, Tatsuhiro Masaoka, Eisuke Iwasaki, Yoshimasa Saito, Toshifumi Hibi Background and Aim: Sonic hedgehog (Shh) is a morphogen involved in the homeostasis of the gastric fundic gland. Shh is soluble signal that is secreted in concentration gradients through a tissue and regulate epithelial cell differentiation. We have previously shown that disturbances of epithelial cell differentiation induced by H. pylori-associated gastritis in Mongolian gerbils are correlated closely with reduced Shh expression (J. Pathol. 206:186, 2005). The alteration of gastric mucosal Shh expression after eradication of H. pylori was examined. Material and Method: Male Mongolian gerbils were inoculated with H. pylori (ATCC43504) at the age of 5 weeks. As eradication treatment, a triple therapy with lansoprazole, amoxicillin and clarithromycin for two days was carried out at 12, 24 or 48 weeks after the inoculation. Gerbils were examined at 10 weeks after the eradication. Gastric inflammation was evaluated by the tissue myeloperoxidase (MPO) activity and by the histological scoring based upon the updated Sydney system. Immunohistochemistry against Shh and H+-K+-ATPase and the in situ hybridization of Shh were performed. Results: H. pylori eradication was confirmed by microaerobic bacterial culture. Shh mRNA expression was clearly localized in the fundic gland region with a gradient in the control and the eradicated gerbils. The MPO activity and scores for acute and chronic inflammation as well as atrophy in the H. pylori eradicated gerbils were significantly decreased compared with those of H. pylori positive, non-eradicated gerbils. The horizontal extension of the area positive for Shh and H+-K+-ATPase expression in the H. pylori eradicated gerbils, was significantly increased as compared with that of H. pylori positive, non-eradicated gerbils (p<0.01). The earlier eradication promoted the better restoration of Shh expression. The 50% of cohorts eradicated at 24 weeks and all cohorts eradicated at 48 weeks exhibited a heterotopic proliferative gland (HPG) which forms hyperplastic mucosa and mucin-containing cystic lesion at the lower gastric body. In the cohort with HPG, the front line of Shh regeneration was cut off at the point of HPG. Conclusion: After H. pylori eradication, sonic hedgehog expression was significantly restored and a significant improvement in gastric atrophy was observed. These results suggest that H. pylori-associated deregulation of Shh expression, that could be linked to gastric atrophy and its associated preneoplastic transformation, is reversible only after the earlier H. pylori eradication.
S1605 A Long-Term PPI Administration Induces Atrophic Corpus Gastritis and Promotes Development of Atypical Glands in Mongolian Gerbils Infected with Helicobacter pylori Tadashi Hagiwara, Ken-ichi Mukaisho, Hiroyuki Sugihara, Takanori Hattori Background: Long-term use of proton pump inhibitors (PPIs) has been reported to worsen corpus atrophic gastritis in patients with Helicobacter pylori (H. pylori) infection. The purpose of this study was to elucidate whether corpus atrophic gastritis is worsened after long-term administrations of PPI using Mongolian gerbils (MGs), which provide an excellent model for studying H. pylori related gastritis and adenocarcinoma . Methods: MGs were separated into 4 groups (n = 5). H. pylori (ATCC43504) was inoculated into groups A and B, PPI was administered to groups A and C, and group D that received no treatment was a control. MGs had access to food containing omeprazole (100 mg/kg body weight/day) for 6 months, according to the recently established protocol (Hagiwara T, et al. Dig Dis Sci, 2007). PPI was administered 6 months after the infection, when pangastritis developed in the infected MGs in. The stomach was removed and cut into 9 sections (6 in fundus and 3 in antrum). We evaluated corpus atrophy using the score of no parietal cells in 6 sections of fundus. First, we calculated a ratio of the area of no parietal cells in each section using hematoxylin and eosin staining, and then we added the ratio of 6 sections. In one animal, the full score was 600, because it had 6 sections in fundus and a full score of one section was defined as 100%. We defined the submucosal gland without atypia as a heterotopic gland, and the submucosal mucinous gland with nuclear and structural atypia as an atypical mucinous gland. Results: Microscopically, more severe neutrophilic and lymphoid infiltrates were detected in group A than in the other groups. There were no atrophic changes in groups C and D. The score of corpus atrophy in group A (317 ± 17.9; mean ± SE) was significantly higher than that in group B (P < 0.0048: student's t-test). Heterotopic glands were found in groups A (5 out of 5) and B (4 out of 5). Atypical mucinous glands were only detected in 3 out of 5 (60%) in group A. Discussion: The scores of corpus atrophy in group A were significantly higher than those in the other groups. Moreover, atypical mucinous glands, which were interpreted as adenocarcinoma in previous studies, were developed in 60% of group A. In general, these atypical mucinous glands are developed in less than 10% at 18 to 24 months after the infection. These findings suggest that long-term administration of PPI induces development of atypical mucinous glands, associated with the progression of atrophic corpus gastritis in MGs infected with H. pylori.
S1608 Coexisting Gastric Cancer and Duodenal Ulcer: Distrubution of Atrophic Gastritis and Intestinal Metaplasia Soo-Jeong Cho, Il Ju Choi, Chan Gyoo Kim, Jong Yeul Lee, Myeong-Cherl Kook Background/Aims: A strong correlation exists between atrophic gastritis/intestinal metaplasia and gastric cancer. Duodenal ulcer (DU) disease characteristically has an antral predominant gastritis and a lower risk for gastric cancer (GC). The aim of this study was to evaluate underlying atrophy and intestinal metaplasia in patients with gastric cancer in the absence or presence of duodenal ulcer. Patients and Methods: A total of 914 patients with stomach cancer or duodenal ulcer were prospectively enrolled between August 2006 and June 2007. The patients were divided into 3 groups; group A: patients with only GC, group B: patients with only DU, and group C: patients with both GC and DU. Underlying gastric histology was evaluated using updated Sydney system at antrum lesser curvature, upper body lesser curvature (UBLC) and upper body greater curvature (UBGC). Helicobacter pylori (H. pylori) was determined by histology and rapid urease test. Comparison of histological grades of each group were analyzed using the Kruskal-Wallis method. Results: The numbers of patients of group A, B, and C were 808, 57, and 50. The coexisting GC and DU patients observed in 5.7% (50/858). Mean ages of three groups were 58, 52, and 54 years, respectively (p=
A-233
AGA Abstracts
AGA Abstracts
Ten-Year Follow-Up Study On the Incidence of Gastric Cancer and the Pathological Changes of Gastric Mucosa After H. pylori Eradication in China Liya Zhou
AGA Abstracts
0.005). There was no difference in the male to female ratio and in positivity for H. pylori test among the three groups (p=0.509 and 0.694). No differences were not found in the histological differentiation and tumor stages between group A and C (p=0.370 and 0.238). Stages of duodenal ulcer in group B and C did not show any difference between group B and C (p=0.779). Mean scores of atrophy and intestinal metaplasia of group C at antrum were 1.91±0.88 and 1.51±1.18, which were similar with those of group A (1.86±1.13 and 1.46±1.22) and were significantly higher than those of group B (1.35±0.85 and 0.74±0.89) (p=0.004 and <0.001). Mean scores of atrophy and intestinal metaplasia of group C at UBLC were 0.87±1.26 and 0.79±1.06, which were lower than those of group A (1.62±1.30 and 1.39±1.22) and were higher than those of group B (0.22±0.71 and 0.16±0.54) (p<0.001 and <0.001). Conclusion: DU is not rare in GC patients. Even in DU patients, those with more severe atrophy and intestinal metaplasia at corpus as well as at antrum may have a higher risk for the development of gastric cancer.
S1611 Effect of H. pylori Infection On Expression of TFF2 in Rhesus Monkeys Matthew Goldman, Cristina Semino-Mora, Arifur Rahman, Hui Liu, Wilfred De La Cruz, Carolyn A. Sullivan, Andre Dubois Background: The trefoil peptides are proteins important in mucosal defense and repair. TFF2, in particular, plays a crucial role in the process of mucosal healing. H. pylori causes peptic ulcer disease and gastric cancer, and has been found to modify TFF2 expression. However, there is little information regarding TFF2 expression during the course of the natural history of gastric disease. Methods: In order to simulate a clinical situation, we investigated the effect of H. pylori infection on the expression of TFF2 in 23 Rhesus monkeys by performing gastroscopies with gastric biopsies. The monkeys were divided into four groups: controls (C), H. pylori infected (H), ethyl-nitro-nitrosoguanidine (ENNG), and H. pylori + ENNG (HE). H. pylori infection was confirmed by histology, culture, and RTPCR. TFF2 expression was determined by immunohistochemistry (IHC) using an anti-TFF2 polyclonal antibody and by in situ hybridization (ISH) using a probe specific for rhesus monkey TFF2. Quantification was performed using a semi-automated computer program and the MATLAB platform. Results: After 5 years of ENNG administration, gastric antral biopsies of these three HE monkeys showed focal intestinal metaplasia with epithelial hyperplasia. One of these animals was found to have developed high grade dysplasia in an antral polyp. TFF2 expression trended towards an increase in H and HE monkeys over the control group. However, at 60-months, the HE monkeys with dysplasia had lower TFF2 expression compared to the other HE animals, but the difference was not statistically significant (dysplasia: 0.28 ± 8%, no dysplasia: 0.36 ± 2%). Discussion: Long-term, persistent, H. pylori infection is associated with a trend towards an increase in TFF2 expression, but this increase is curbed as precancerous lesions appear. The decreased TFF2 expression seen in monkeys with dysplasia supports the role of TFF2 in mucosal protection, suggesting that decreased expression may serve as an early indicator of neoplasia. These observations suggest that dysplasia may develop as TFF2 expression falters during prolonged gastritis.
S1609 Clinical Evaluation of Helicobacter pylori Tyrosine-Phosphorylated CagA in Diffuse-Type Gastric Cancer Patients: A Case-Control Study Yoshihiro Wada, Masanori Ito, Shunsuke Takata, Shosuke Kitamura, Akemi Takamura, Masana Tatsugami, Shinobu Imagawa, Yoshiaki Matsumoto, Shinji Tanaka, Masaharu Yoshihara, Kazuaki Chayama Background: Cytotoxin-associated antigen A (CagA) protein produced by Helicobacter pylori (H. pylori) is proposed to be associated with the pathogenicity of gastric carcinogenesis. CagA is translocated into the gastric epithelial cells and localizes to the inner surface of the plasma membrane, where it undergoes tyrosine phosphorylation at the Glu-Pro-Ile-Tyr-Ala (EPIYA) motif. East Asian CagA has stronger toxicity than Western CagA, and the third domain of the EPIYA motif of East Asian CagA (D site) plays critical role in abnormal intracellular signals, leading to carcinogenesis. Aim: To investigate the pathogenesis of tyrosinephosphorylated CagA in diffuse-type gastric cancer (DGC). Methods: We examined 27 DGC patients (group-DGC; 13 men, mean age 56.9 y.o.) and age-, gender-matched 27 patients with atrophic gastritis (group-AG) as controls. All patients were diagnosed as H. pyloripositive. All DGC patients received endoscopic mucosal resection and histological diagnosis was confirmed. Biopsy specimens (from the antrum and the corpus) and fasting sera were collected from all patients. The grade of histological gastritis (according to the updated Sydney System) and the serum markers of gastritis (pepsinogens and gastrin) were determined. We synthesized 10 mer oligopeptide with tyrosine phosphorylation (CEPIY(P)ATIDF; CagA-P) designed from East Asian CagA-specific EPIYA-D site (Higashi et al. Proc Natl Acad Sci, 2002) as an antigen and originally generated a polyclonal antibody. The expression of CagAP was evaluated by Western blotting and immunohistochemistry. Moreover, serum titers of anti-CagA-P antibody were determined by enzyme linked immunosorbent assay test (Takata S et al. AGA, 2007) using the compounded oligopeptide as a solid phase of an antigen. Results: There was no difference in histological gastritis and in classical serum markers between the two groups. Immunohistochemically, the expressions of CagA-P were detected in the cytoplasm of the surface epithelium. In the corpus specimens, we found statistically higher expressions of CagA-P in group-DGC than those of group-AG (P=0.035). Moreover, the serum titers of anti-CagA-P antibody were significantly higher in group-DGC than those of group-AG (P=0.031). Eleven patients in group-DGC (11/27, 41%) showed both positive expression of CagA-P and high titer of anti-CagA-P antibody, and its prevalence was statistically higher than that of group-AG (5/27, 19%; P=0.014). Conclusions: CagA-P plays an important role in gastric carcinogenesis, especially in DGC. Clinical quantification of antiCagA-P antibody may be useful for the evaluation of DGC risk.
S1612 Helicobacter pylori Infection Diminish the IFN-γ Secretion By T Lymphocytes in Response to Stimulation with Different Agents in Children Czkwianianc Elzbieta, Wieslawa Rudnicka, Magdalena Chmiela, Ewa Malecka-Panas Despite generating an inflammatory response to Helicobacter pylori (H. pylori) infection, the immune system usually fails to clear the bacteria. Humoral response induced by H. pylori has no role in the eradication, cellular response depending on the type of T-lymphocytes(Th1 or Th2) cells infiltrating gastric mucosa, may be more harmful than beneficial to the host. The aim of the study was the investigation of cellular response to H. pylori infection in children. Material and methods. In Vivo study: 53 consecutive dyspeptic children aged 617y with chronic dyspeptic symptoms underwent upper GI endoscopy with gastric biopsy. Endoscopy lesions and pathology scoring with upgraded Sydney System in the biopsies were estimated as well as H. pylori infection status by pathology and urease test (UT). Blood sample from all examined children was taken to determine sera IgG-antibodies with ELISA test, sera IgG-antibodies to antigen cagA with ELISA test and to obtain peripheral blood mononuclear leucocytes (PBML). In Vitro study: Peripheral blood mononuclear leucocytes (PBML) were isolated from the blood for culture and examine the cell ability to secrete IFNγ after stimulate them with different factors: H. pylori heated rods and H. pylori heated rods in the interleukin 2 (IL2) milieu as well as with Il2 alone. Enumerated level of IFN-g concentration in the supernatant of the PBMC culture received as a difference between those two last above mentioned results. Results: 23 of all examined children (group I) were H. pylori infected (positive UT, pathology and serology) and 30 were not. Among them 14 children (group II) were H. pylori positive in serology at very low titres and 16 (group III) were serological negative. There was no endoscopic, histological and IFN-γ production differences between the group II and III. PBML from H. pylori infected children responded to H. pylori bacteria by IFN-γ production to a lower degree of concentration then in PBML from not infected patients (419±1041.9 ng/ml and 1642.2±2509.9 ng/ml,p<0.05). A week, but positive and significant statistically correlation between IFN-γ and chronic gastritis degree in the children H. pylori(+) (R=0.4603, p=0.03) was found. Strong and statistically significant correlation between anti-CagA-Ab and gastric glands atrophy in the children H. pylori(+) was seen (R=0.6406, p=0.007). Conclusions: H. pylori has weakened the cellular response to the infection what may favour the long lasting gastric colonization and the bacterial induced epithelial damage. In addition to weakening of cellular response to the infection, IFN-γ causes gastric mucosal damage in children.
S1610 Effects of Helicobacter pylori-Secreting Protein Tip α On the Human Gastric Epithelial Cell GES-1 Shi R. Hua, Ping Cheng, Hongjie Zhang Aims: To investigate the effects of tumor necrosis factor-α-inducing protein (Tip α) from H. pylori on human gastric epithelial cell line GES-1. Methods: The Tip α gene located in HP0596 was extracted from genome sequence of H. pylori strain 26695 and its open reading frame (ORF) was cloned into the eukaryotic expressing vector pcDNA3.1. Recombinant pcDNA3.1-Tipα and empty plasmid pcDNA3.1 were transfected into GES-1 cells by using the lipofectomine 2000, and the G418-resistent clones were screened. Normal GES-1 cells and with empty vector pcDNA3.1 were used as the control groups. The influences of Tip α protein on the cells proliferation, apoptosis, cell cycles by MTT assay and Flow Cytometry concentration of TNF-α, IL-1β, IL-8 were examined by ELISA, and expression of Bcl-2 and P53 gene were determined by Western Blot. Results: 1. The growth curve showed that the growth of Tip α gene transfected cells was faster, compared with control groups.2.Cell cycle analyzed by flow cytometry showed an increase in the proportion of the S-phase in the Tip α gene transfected cells, but a decrease in the G1-phase, apoptosis rate was significant lower than that of the controls. 3. ELISA assay showed that the inner cell concentration of TNFα was 49.801±5.960, 48.215±5.620, 47.777±5.754 (pg/ml) in the Tip α transfected group, empty vector transfected group and normal GES-1 cell group respectively, and there was no significance in all groups(p>0.05), while the medium concentration was 41.744±0.424, 31.654±1.404, 30.234±0.908 (pg/ml) respectively, and there was significant difference between the transfected group and the control groups(p<0.05). ELISA assay also showed the inner and outer cell concentrations of IL-1β were 93.886±5.082, 74.267±9.606, 69.550±10.491 and 58.474±6.927, 32.573±3.823, 30.686±2.898(pg/ml) in the transfected group, empty vector group and GES-1 cell group respectively, and IL-8 were 69.130±9.249, 44.002±5.497, 37.756±10.742 and 191.348±1.169, 40.396±8.901, 38.197±6.991(pg/ml) in the transfected group, empty vector group and GES-1 cell group respectively. The concentrations of IL-1β and IL-8 in the transfected group were higher than that in controls (p<0.05). 4. Expression of Bcl-2 gene in the transfected cells was up-regulated, while expression of P53 gene was suppressed.
AGA Abstracts
S1613 Role of Free Radical and Mucus in Rat Experimental Model of Gastritis with Ammonia; Combined Effect of Anti-Ulcer Agent Geranylgeranylacetone Eiji Umegaki, Takao Noguchi, Keishi Kojima, Nanako Shiraishi, Toshihisa Takeuchi, Satoshi Tokioka, Yukiko Yoda, Nozomi Takeuchi, Chikako Eiraku, Kazuhide Higuchi Background and aim: There are reports that Helicobacter pylori degrades mucin and undermines gastric mucosal integrity. On the other hand, there are reports that mucin acts as free radical scavengers in gastric mucosa. In this study, we used the rat experimental model of gastritis with ammonia and assessed the effects of ammonia on the gastric mucosa and gastric mucus, and whether free radicals are involved in the induction of gastric mucosal lesions. In addition, we evaluated the effect of novel anti-ulcer agent geranylgeranylacetone (GGA). Materials and methods: Male Wistar rats were used and sacrificed 6 weeks after the beginning of the study. Gastric mucosal injury was induced by giving 0.1% ammonia water ad libitum for 6 weeks. Group A; Water was offered ad libitum for 6 weeks. Group B; 0.1% ammonia water was offered ad libitum for 6 weeks. Group C; 0.1% ammonia water ad libitum and 200 mg/kg/day of GGA were administrated orally for 6 weeks. The tissue sections of removed stomach were prepared to measure the thickness of gastric mucosa and to stain superficial mucus by PAS and deep mucus by concanavalin A. The quantity of each positive
A-234