Gastric H. pylori infection alters the expression patterns of all major secretory proteins in the antrum

3621

in all the resistant cells. 4. SinceA and N affect predominantlycells with malignant phenotype they may provide a new modality approach in cancer therapy.

Prevalence and Distribution of Helicobacter pylori Induced Gastritis in Patients with Iron Deficiency Anemia Without Source of GI-Bleeding After a Close Endoscopic Examination of the Upper and Lower GI-Tract Dieter Schilling, Gabriele Grieger, Erik Weidmann, Dept of Gastroenterology,Ludwigshafen Germany; Thomas Nuesse, Dept of Pathology, Ludwigshafen Germany; Juergen F. Riemann, Dept of Gastroenterology,Ludwigshafen Germany

Arrayedgeneswith at least 3 fold increase/decreasein geneexpression

Up-regulation Downregulation*

IR-A (IC~o=300)

IR-N(IC~=350)

R1N(ICso=200)

8 50

16 22

2 3

R1.A((ICso=250) 13 5

Introduction:Epidemiology and therapy studies suggest a pathogenic role of Helicobacter pylori (H.pylod)- infection in the developmentof iron deficiencyanemia (IDA). We investigated the prevalenceand the characteristics of H.pylod induced gastritis in patients with IDA and a proven source of GI bleeding (G1) in comparison to patients without source of GI bleeding (G2) in spite of a close endoscopic and radiographic examination. Methods:In all patients two specimens from antral and two specimensfrom corpus mucosa were obtained. H.pylori infection was diagnosed by Histology (HE and in cases of doubt Warthin Starry staining). Grading of the severity of gastritis was pedormed Toyusing the Houston modification of the SydneySystem.We comparedthe gastric grading of the patients of Gl(n = 37,meanage 59.1 years) with G2 (negative upper and lower GI endoscopy, enteroscopy, angiography and scintigraphic examinations;n= 42,meanage 58.9 years) and with an age and gender matched control of dyspeptic people without anemia (=G3). Results: The prevalence of H.pylori infection was statistically significant different between G1 (57%) and G2 (38%) but not between G2 and G3 (46%).Pangastdtis or corpus dominant gastritis was more frequent in G2 (78%) in comparison to G1(14%)or G3(12%). Conclusion:This data suggest that older patients with IDA without visible source of gastrointestinal bleeding have a special pattern of H.pylod induced gastritis. This is a pangastritis with corporal inflammation which may cause acid suppression and influence iron absorption. Further prospective studies are needed to prove this hypothesis.

*As comparedto the parentalnon resistantcells 3619 Rnsveratroi induces FAS-dependentand FAS-independentApoptosis in Human Gastric Adenocercinoma Cells, While Remaining Nontoxicto Animals Ernesto Godoy-Romero,Mary Jo Atten, Bashar M. Attar, Thomas Milson, Cook County Hosp, Chicago, IL; Michael L. Mihalov, Univ of Illinois, Chicago, IL; Oksana Holian, Cook County Hosp, Chicago, IL Resveratrol is emerging as a candidate chemoprsventiveagent and we have already shown that it suppresses proliferation of gastric adenocarcinomacells, inhibits cellular PKC activity and alters cellular expression of PKC isoforms, and induces apoptosis in gastric adenocarcinoma cells (Gastro 2000, 118:A272). This study describes its mechanism of action as a proapoptotic agent with the aim of further assessing its chemopreventiveand chemotherapeutic potential. METHODS:Balb/c mice receiveddaily resveratrolinjections (1 mg/day) for 30 days. Serum alanineaminotransferaseand creatinine levels were used to determineorgan function, Tissue histology was evaluatedto assess organ integrity. DNA fragmentation was used as an index of apoptosisin gastric adenocarcinomaKATO-IIIand SNU-1 cells treated with rasveratrol alone or in combination with etoposide. Expression of FAS receptor and FAS ligand were determined by Western blot analysis, and flow cytometry was used to determinetime related changes in the FAS receptor. RESULTS: Balb/c mice, subjected to daily administration of large doses of resveratrol displayed normal tissue histology with no significant changes in either serum creatinineor alanineaminotransferaselevels. Resveratrolinducedtime-dependent apoptosis, but sub-optimal concentrations of resveratrol failed to potentiate the apoptotic index of etoposide. SNU-1 cells expressthe wild type FAS receptor and resveratroltreatment resulted in increased FAS expression, whereas KATO-III cells have a mutated FAS receptor that did not respond to resveratrol treatment. However, resveratroltreatment still resulted in increased expressionof the FAS ligand in KATO-III cells. CONCLUSIONS:Balb/c mice tolerate resveratrolwell with no apparentliver or kidneytoxicity, while resveratrolinducesapoptosis of gastric cancer cells in vitro. Resveratrolinducesapoptosis by FAS dependentand independent mechanisms, as evidenced by increased expression of the FAS protein in cells expressing wild type FAS receptor (SNU-1), whereas in cells with deleted FAS (KATO-III) resveratrol elicited an increase in expression of the FAS ligand, suggestingthat this FAS ligand in KATeIII cells interacts with other cellular receptors to trigger apoptotic cell death. Resveratrol appears to interact with cell surface moieties used by etoposide suggesting its feasibility not only as a chemopreventivebut also as a chemotherapeuticagent.

3622 Gastric He pylori Infection Alters the Expression Patterns of All Major Secretory Proteins in the Antrum Jeroen H B Van de Bovenkamp,Anita M. Korteland-Vanmale, Lab Pediatric, Erasmus Univ, Rotterdam Netherlands; Hans A. Bueller, Sophia Children's Hosp, Rotterdam Netherlands; Alexandra W C Einerhand,Jan Dekker, Lab Pediatric, Erasmus Univ, Rotterdam Netherlands Background/Aims:Antrum glands of the stomach make 3 major groups of secretory proteins that are deemedessentialfor antral functions: Mucins (MUC, protective mucus layer), trefoil peptides (TFF, epithelial restitution) and enteroendocdneproteins like gastrin and chromogranin A (CGA). Gastdc H.pyloriinfection leads to inflammation and altered tissue dynamics. We studied the alterations in expressionof the secretory proteins in order to better understand the role of H. pylori in gastric disease. Methods: We examinedduplicate antrum biopsies of 81 patients (39 H. py/ori-positive). In each biopsy expressions patterns were examined by immunohistochemistry: MUC2, MUC5AC, MUC5B, MUC6, TFF1, TFF2, TFF3, gastdn, CGA, and the proliferation marker Ki-67. Expression was quantified morphometdcally. Results: Proliferation was found in the lower gland region in controls, but was significantly increased in frequency and was found significantly higher up in the glands in infected tissue. MUC2 expression was confined to goblet cells in occasionalfocal patches of intestinal metaplasia. MUC5AC was found in the surface epithelial cells, which were significantly decreased in number in the infected tissue. At the same time the number of cells expressing MUC6 and MUC5B (that were always co-expressed)were increasedin the infected tissue. TFF1 and TFF2 were found in most cells of the glands in healthytissue, but were both significantly diminished in H. pylori infection: TFFl-expressing cells were mostly absent in the bottom half of the glands, while TFF2-expressingcells were particularly scarce in the neck region of the glands. TFF3 expression was observed at low levels in most epithelial cells and was not affected in infected tissue. TFF3 was also found in MUC2-posifive goblet cells in patches of intestinal metaplasia. Gastdn and CGA primarily co-localised and the number of positive cells was not significantly affected by H. pyloriinfection, yet the zone of expressionwas significantly closer to the surface than in healthy tissue. Conclusions: In H. py/ori-infected tissue, the cells expressingthe major protective mucin MUC5ACwere partly replacedby ceils producing MUC6 and MUC5B, whereas the major protective trefoil factors, TFF1 and TFF2 were expressedin a smaller percentage of cells. Altered expression of protective proteins, most tikety due to increased epithelial turnover, may explain the increasedvulnerability of the gastric tissue in H.pylori-related pathology.

3620 Heparin Binding Epidermal Growth Factor-Like Growth Factor and Amphirogulin UpregulaUon in Helicobacter pyleri Gastritis in Humans Marco Romano, ConcettaTuccillo, BarbaraA. Manzo, Seconda Universita' di Napoli, Napoli Italy; Gerardo Nardone, Alba Rocco, Ststania Staibano, Mariella Santangelo, Nicola Della Valle, Giuseppe D'Argenio, RaffaeleZarrilli, Universita' Fed II, Napoli Italy Background:/4.pylorhinduced gastroduodenaldiseasedependson the production of specific virulence factors which damagethe gastric mucosa and impair the mechanisms of mucosal healing and on the response of the host to the infection. Epidermal growth factor (EGF)related peptides are important modulators of gastric homeostasis in normal and damaged gastrointestinalmucosa.Aim: 1} to evaluatethe expressionof hepadnbinding EGF-likegrowth factor (HB-EGF) and amphiregulin (AR), members of the EGF-relatedpeptide family, in the antral mucosa of dyspeptic patients with or without H. priori infection; 2) to correlate the levels of HB-EGFand AR with the mitogenic activity of antral gastric epithelial cells. Patients and Methods: 1) We studied 10 H. pylori-infected and 10 H. py/ori noninfected dyspeptic patients; 2) Diagnosis of H. pylori infection: by rapid urease test and histology; 3) HB-EGF and AR mRNA expression:by RT-PCR;4) HB-EGFand AR protein expressionand localization: by immunohistochemistry; 5) Mitogenic activity: by determinationof proliferating cell nuclear antigen (PCNA) labelling index; 6) Statistics: Wilcoxon rank sum test and linear regression. Results: 1) HB-EGFmRNA levels in the gastric antrum were 2.5 fold higher (median 1.15, range 0.62-1.45 vs median 0.46, range 0.2-0.7 HB-EGF/GAPDHarbitrary units, p
3623 Effect of Helicobacter pyiori infection on Epidermal Growth Factor Receptor (EGFR) Expression and Cell Proliferation of Gastric Epithelial Mucosa Zsuzsa Unger, Bela Molnar, II Dept of Medicine, Semmelweis Univ, Budapest Hungary; Matthias Ebert, Dept of Gastroenterology,Univ of Magdeburg, Magdeburg Germany; Laszlo Pmnai, ]1 Dept of Medicine, Semmetweis Univ, Budapest Hungary; Peter Maitertheiner, Dept of Gastroenterology,Univ of Magdeburg, Magdeburg Germany; Zsolt Tulassay, II Dept of Medicine, Semmelweis Univ, Budapest Hungary Background: H.pylori(Hp.) inhibits the interaction between EGFRand its ligand which impairs the proliferation capability of epithelial cells and mucosal damage recovery, in vitro. The authors examined whether Hp. infection affects the expression of EGFR and proliferation activity of gastric mucosal epithelia in paraffin embedded human samples. Materials and methods: Paraffin embedded tissue samples were analysed by EGFR and proliferation cell nuclear antigen (PCNA) immunohistochemical methods (45 male, 41 female of age averaging at 58,5 years within a range of 33-87 years). Sampleswere grouped on the basis of histology: normal epithelia (n = 9), chronic gastritis without Hp. (n = 29), chronic gastritis without Hp. with intestinal metaplasia (n = 10), Hp. associated gastritis (n = 28), Hp. associatedgastritis with intestinal metaplasia (n=lO). Results: In healthy epithelia a positive correlation was found between PCNAand EGFR.However in Hp. positive gastritis with and without intestinal metaplasianegativecorrelation was detected.Also significant negativecorrelation was obtained

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