幽门螺杆菌对胃上皮细胞分泌IL-8的影响

目的：了解幽门螺杆菌（Ｈｐ）对胃上皮细胞分泌ＩＬ－８的影响。方法：将Ｈｐ与胃上皮细胞共同孵育２４ｈ，ＥＬＩＳＡ法检测上清液中ＩＬ－８的浓度。结果：Ｈｐ可直接诱导胃上皮细胞分泌ＩＬ－８；热灭活、甲醛溶液固定后的菌株该作用明显减弱（Ｐ＜０．０１）；含有细胞毒素相关基因Ａ（ｃａｇＡ）株的诱导作用大于不含ｃａｇＡ株，差异明显（Ｐ＜０．０５）。结论：Ｈｐ能够刺激胃上皮细胞分泌ＩＬ－８；

In vitro assessment of gastrointestinal viability of two photosynthetic bacteria,Rhodopseudomonas palustris and Rhodobacter sphaeroides

The objectives of this study were to assess the potential of two photosynthetic bacteria （PSB）, Rhodopseudomonas palustris HZ0301 and Rhodobacter sphaeroides HZ0302, as probiotics in aquaculture. The viability of HZ0301 and HZ0302 in simulated gastric transit conditions （pH 2.0, pH 3.0 and pH 4.0 gastric juices） and in simulated small intestinal transit conditions （pH 8.0, with or without 0.3% bile salts） was tested. The effects of HZ0301 and HZ0302 on the viability and permeability of intestinal epithelial cell in primary culture of tilapias, Oreochrornis nilotica, were also detected. All the treatments were deter- mined with three replicates. The simulated gastric transit tolerance of HZ0301 and HZ0302 strains was pH-dependent and correspondingly showed lower viability at pH 2.0 after 180 min compared with pH 3.0 and pH 4.0. Both HZ0301 and HZ0302 were tolerant to simulated small intestine transit with or without bile salts in our research. Moreover, there was no significant difference （P〉0.05） among three treatments including the control and the groups treated with HZ0301 or HZ0302 both in intestinal epithelial cell viability and membrane permeability, showing no cell damage. In summary, this study demonstrated that HZ0301 and HZ0302 had high capacity of upper gastrointestinal transit tolerance and were relatively safe for intestinal epithelial cells of tilapias.

Gene expression profile differences in gastric cancer, pencancerous epithelium and normal gastric mucosa by gene chip

AIM: To study the difference of gene expression in gastric cancer (T), pericancerous epithelium (P) and normal tissue of gastric mucosa (C), and to screen an associated novel gene in early gastric carcinogenesis by oligonudeotide microarray.METHODS: U133A (Affymetrix, Santa Clara, CA) gene chip was used to detect the gene expression profile difference in T, P and C, respectively. Bioinformatics was used to analyze the detected results.RESULTS: When gastric cancer was compared with normal gastric mucosa, 766 genes were found, with a difference of more than four times in expression levels. Of the 766 genes,530 were up-regulated (Signal Log Ratio [SLR]＞2), and 236 were down-regulated (SLR＜-2). When pericancerous epithelium was compared with normal gastric mucosa, 64genes were found, with a difference of more than four times in expression levels. Of the 64 genes, 50 were up-regulated (SLR＞2), and 14 were down-regulated (SLR＜-2). Compared with normal gastric mucosa, a total of 143 genes with a difference in expression levels (more than four times, either in cancer or in pericancerous epithelium) were found in gastric cancer (T) and pericancerous epithelium (P). Of the 143 genes, 108 were up-regulated (SLR＞2), and 35were down-regulated (SLR＜-2).CONCLUSION: To apply a gene chip could find 143 genes associated with the genes of gastric cancer in pericancerous epithelium, although there were no pathological changes in the tissue slices. More interesting, six genes of pericancerous epithelium were up-regulated in comparison with genes of gastric cancer and three genes were down-regulated in comparison with genes of gastric cancer. It is suggested that these genes may be related to the carcinogenesis and development of early gastric cancer.

Relevance of MUC1 mucin variable number of tandem repeats polymorphism in H pylori adhesion to gastric epithelial cells

AIM:To evaluate the influence of MUC1 mucin variable number of tandem repeats (VNTR) variability on H pylori adhesion to gastric cells. METHODS: Enzyme linked immunosorbent assay (ELISA)-based adhesion assays were performed to measure the adhesion of different H pylori strains (HP26695 and HPTx30a) to gastric carcinoma cell lines (GP202 and MKN45) and GP202 clones expressing recombinant MUC1 with different VNTR lengths. RESULTS: Evaluation of adhesion results shows that H pylori pathogenic strain HP26695 has a significantly higher (P < 0.05) adhesion to all the cell lines and clones tested, when compared to the non-pathogenic strain HPTx30a. Bacteria showed a significantly higher (P < 0.05) adhesion to the GP202 cell line, when compared to the MKN45 cell line. Furthermore, both strains showed a significantly higher (P < 0.05) adhesion to GP202 clones with larger MUC1 VNTR domains. CONCLUSION: This work shows that MUC1 mucin variability conditions H pylori binding to gastric cells. The extent of bacterial adhesion depends on the size of theMUC1 VNTR domain. The adhesion is further dependent on bacterial pathogenicity and the gastric cell line. MUC1 mucin variability may contribute to determine H pylori colonization of the gastric mucosa.

Erythropoietin -induced proliferation of gastric mucosal cells

AIM： To analyze the localization of erythropoietin receptor on gastric specimens and characterize the effects of erythropoietin on the normal gastric epithelial proliferation using a porcine gastric epithelial cell culture model. METHODS： Erythropoietin receptor was detected by RT-PCR, Western blotting and immunohistochermistry. Growth stimulation effects of erythropoietin on cultured gastric mucosal cells were determined by ELISA using bromodeoxyuridine （BrdU）. RESULTS： Erythropoietin receptor was detected on cultured porcine gastric mucosal epithelial cells. Erythropoietin receptor was also detected histochemically at the base of gastric mucosal epithelium. BrdU assay demonstrated a dose-dependent increase in growth potential of cultured porcine gastric mucosal epithelial cells by administration of erythropoietin, as well as these effects were inhibited by administration of antierythropoietin antibody （P〈 0.01）. CONCLUSION： These findings indicate that erythropoietin has a potential to proliferate gastric mucosal epithelium via erythropoietin receptor.

Ghrelin attenuates gastrointestinal epithelial damage induced by doxorubicin

AIM:To examine the influence of ghrelin on the regenerative potential of gastrointestinal(GI)epithelium.METHODS:Damage to GI epithelium was induced in mice by two intravenous injections of doxorubicin(10 and 6 mg/kg).Some of the doxorubicin-treated mice received a continuous subcutaneous infusion of ghrelin(1.25μg/h)for 10 d via implanted mini-osmotic pumps.To label dividing stem cells in the S-phase of the cell cycle,all mice received a single intraperitoneal injection of 5'-bromo-2'-deoxyuridine(BrdU)one hour before sacrifice.The stomach along with the duodenum were then removed and processed for histological examination and immunohistochemistry using anti-BrdU antibody.RESULTS:The results showed dramatic damage to the GI epithelium 3 d after administration of chemotherapy which began to recover by day 10.In ghrelintreated mice,attenuation of GI mucosal damage was evident in the tissues examined postchemotherapy.Immunohistochemical analysis showed an increase in the number of BrdUlabeled cells and an alteration in their distribution along the epithelial lining in response to damage by doxorubicin.In mice treated with both doxorubicin and ghrelin,the number of BrdUlabeled cells was reduced when compared with mice treated with doxorubicin alone.CONCLUSION:The present study suggests that ghrelin enhances the regenerative potential of the GI epithelium in doxorubicintreated mice,at least in part,by modulating cell proliferation.

Detection of H.pylori DNA in gastric epithelial cells by in situ hybridization

AIM: To investigate the presence of H.pylori DNA within gastric epithelial cells in patients with H.pylori infection and its possible carcinogenic mechanism. METHODS: Total 112 patients, with pathologically confirmed chronic superficial gastritis, chronic atrophic gastritis, intestinal metaplasia, atypical hyperplasia or gastric cancer were studied. Among them, 28 were H.pylori negative and 84 H.pylori positive. H.pylori DNA in gastric epithelial cells was detected by GenPoint catalyzed signal amplification system for in situ hybridization. RESULTS: In the H.pylori positive group, zero out of 24 chronic superficial gastritis (0.0%), four out of 25 precancerous changes (16.0%) and thirteen out of 35 gastric cancers (37.1%) showed H.pylori DNA in the nucleus of gastric epithelial cells, the positive rates of H.pylori DNA in the nucleus of gastric epithelial cells were progressively increased in chronic superficial gastritis, precancerous changes and gastric cancer groups (chi(2)=12.56, P=0.002); One out of 24 chronic superficial gastritis (4.2%), eleven out of 25 precancerous changes (44.0%) and thirteen out of 35 gastric cancers (37.1%) showed H.pylori DNA in the cytoplasm of gastric epithelial cells (chi(2)=10.86, P=0.004). In the H.pylori negative group, only one patient with gastric cancer was found H.pylori DNA in the nucleus of gastric epithelial cells; Only two patients, one patient with precancerous changes and another with gastric cancer, showed H.pylori DNA in the cytoplasm of gastric epithelial cells. Furthermore, H.pylori DNA must have been in the cytoplasm as long as it existed in the nucleus of gastric epithelial cells. CONCLUSION: H.pylori DNA exists both in the nucleus and the cytoplasm of gastric epithelial cells in patients with H.pylori infections. The pathological progression from chronic superficial gastritis, precancerous changes to gastric cancer is associated with higher positive rates of H.pylori DNA presence in the nucleus of gastric epithelial cells.

Epithelial-mesenchymal transition mediated tumourigenesis in the gastrointestinal tract

Epithelial-mesenchymal transition (EMT) is a highly conserved process that has been well characterised in embryogenesis. Studies have shown that the aberrant activation of EMT in adult epithelia can promote tumour metastasis by repressing cell adhesion molecules,including epithelial (E)-cadherin. Reduced intracellular adhesion may allow tumour cells to disseminate and spread throughout the body. A number of transcription proteins of the Snail superfamily have been implicated in EMT. These proteins have been shown to be over-expressed in advanced gastrointestinal (GI) tumours including oesophageal adenocarcinomas,colorectal carcinomas,gastric and pancreatic cancers,with a concomitant reduction in the expression of E-cadherin. Regulators of EMT may provide novel clinical targets to detect GI cancers early,so that cancers previously associated with a poor prognosis such as pancreatic cancer can be diagnosed before they become inoperable. Furthermore,pharmacological therapies designed to inhibit these proteins will aim to prevent local and distant tumour invasion.

Effects of Helicobacter pylori infection on gastric epithelial cell kinetics in patients with chronic renal failure

AIM： To evaluate the effects of Helicobacter pylori infection on gastric epithelial cell kinetics in patients with chronic renal failure （CRF）. METHODS： Forty-four patients were enrolled in this study and divided into four groups with respect to their Helicobacter pylori （H pylori） and CRF status. Groups were labeled as follows： la： normal renal function, H pylori negative （n = 12）, lb： normal renal function, H pylori positive （n = 11）, 2a： CRF, H pylori negative （n = 10）, 2b： CRF, H pylori positive （n = 11）. Upper gastrointestinal endoscopy was done in all the patients involved in the study. During endoscopical investigation, antral biopsy specimens were taken from each patient. In order to evaluate the cell apoptosis and proliferation in gastric epithelial cells, Bax and proliferating cell nuclear antigen （PCNA） labeling indexes （LI） were assessed with immunohistochemical staining method. RESULTS： For groups la, lb, 2a, and 2b, mean Bax LI was identified as 34.4±13.7, 44.1±16.5, 46.3±20.5, 60.7±13.8, respectively and mean PCNA LI was identified as 36.2±17.2, 53.6±25.6, 59.5±25.6, 67.2±22, respectively. When the one-way ANOVA test was applied, statistically significant differences were detected between the groups for both Bax LI （P = 0.004 〈0.01） and PCNA LI （P = 0.009 〈0.01）. When groups were compared further in terms of Bax LI and PCNA LI with Tukey＇s HSD test for multiple pairwise comparisons, statistically significant difference was observed only between groups la and 2b （P = 0.006 〈0.01）.CONCLUSION： In gastric epithelial cells, expression of both the pre-apoptotic protein Bax and the proliferation marker PCNA increase with H pylori infection. This increase is more evident in patients with uremia. These findings suggest that uremia accelerates apoptosis and proliferation in gastric epithelial cells.

Effects of folic acid on epithelial apoptosis and expression of Bcl-2 and p53 in premalignant gastric lesions

AIM: To evaluate the effects of folic acid on epithelial apoptosis and expression of Bcl-2 and p53 in the tissues of premalignant gastric lesions. METHODS: Thirty-eight patients, with premalignant gastric lesions including 18 colonic-type intestinal metaplasia (IM) and 20 mild or moderate dysplasia, were randomly divided into a treatment group (n = 19) receiving folic acid 10 mg thrice daily and a control group (n = 19) receiving sucralfate 1 000 mg thrice daily for 3 mo. All patients underwent endoscopies and four biopsies were taken prior to treatment and repeated after concluding therapy. Folate concentrations in gastric mucosa were measured with chemiluminescent enzyme immunoassay. Epithelial apoptosis and the expression of Bcl-2 and p53 protein in gastric mucosa were detected with flow cytometric assay. RESULTS: The mean of folate concentration in gastric mucosa was 9.03±3.37 μg/g wet wt in the folic acid treatment group, which was significantly higher than 6.83±3.02 μg/g wet wt in the control group. Both the epithelial apoptosis rate and the tumor suppressor p53 expression in gastric mucosa significantly increased after folic acid treatment. In contrast, the expression of Bcl-2 oncogene protein decreased after folic acid therapy. CONCLUSION: These data indicate that folic acid may play an important role in the chemoprevention of gastric carcinogenesis by enhancing gastric epithelial apoptosis in the patients with premalignant lesions.

Macrophage migration inhibitory factor stimulated by He/icobacter py/oriincreases proliferation of gastric epithelial cells

AIM: Helicobacter pylori (H pylori) is associated with increased gastric inflammatory and epithelial expression of macrophage migration inhibitory factor (MIF) and gastric epithelial cell proliferation. This study aimed at determining whether H pylori directly stimulates release of MIF in monocytes, whether the cag pathogenicity island (PAI) is involved for this function, and whether MIF stimulated by H pylori increases gastric epithelial cell proliferation in vitro. METHODS: A cytotoxic wild-type H pylori strain (TN2), its three isogenic mutants (TN2Δcag,TN2ΔcagA and TN2ΔcagE) were co-cultured with cells of a human monocyte cell line, THP-1, for 24 h at different organism/ cell ratios. MIF in the supernatants was measured by an ELISA. Cells of a human gastric cancer cell line, MKN45, were then co-cultured with the supernatants, with and without monoclonal anti-MIF antibody for 24 h. The cells were further incubated for 12 h after addition of 3H-thymidine, and the levels of incorporation of 3H-thymidine were measured with a liquid scintillation counter. RESULTS: The wild-type strain and the isogenic mutants, TN2ΔcagA and TN2ΔcagE, increased MIF release at organism/cell ratios of 200/1 and 400/1, but not at the ratios of 50/1 and 100/1. However, the mutant TN2Δcag did not increase the release of MIF at any of the four ratios. 3H-thymidine readings for MKN-45 cells were significantly increased with supernatants derived from the wild-type strain and the mutants TN2ΔcagA and TN2ΔcagE, but not from the mutant TN2Δcag. Moreover, in the presence of monoclonal anti-MIF antibody, the stimulatory effects of the wild-type strain on cell proliferation disappeared. CONCLUSION: H pylori stimulates MIF release in monocytes, likely through its cag PAI, but not related to cagA or cagE. H pylori-stimulated monocyte culture supernatant increases gastric cell proliferation, which is blocked by anti-MIF antibody, suggesting that MIF plays an important role in H pylori-induced gastric epithelial cell proliferation.

Expression of some tumor associated factors in human carcinogenesis and development of gastric carcinoma

AIM: To study the effect of IGF-1/IGF-1R and gastrin/CCK-BR on carcinogenesis and development of human gastric carcinoma and to explore its mechanism and provide a credible theoretical foundation for early diagnosis and molecular therapy of gastric carcinoma.METHODS: mRNA expression levels of IGF-1/IGF-1R and gastrin/CCK-BR were assessed by RT-PCR method in gastric cancer tissues, adjacent mucosa, and tumor-free tissues from 56 patients with gastric carcinoma and normal gastric mucosae from 56 healthy controls. Tissue specimens were obtained by biopsy and confirmed by histological evaluation.RESULTS: The mRNA levels of IGF-1/IGF-1R were increased in gastric cancer tissues compared with normal tissues from healthy controls and successively increased in tumor-free tissues, adjacent mucosa, and gastric cancer tissues. The mRNA levels of gastrin/CCK-BR were increased in gastric cancer tissues compared with normal tissues from healthy controls. There was a significant difference between gastric cancer tissues and adjacent mucosa and tumor-free tissues, but the mRNA levels of gastrin were not significantly increased in adjacent mucosa and gastric cancer tissues compared with tumorfree tissues. The mRNA levels of CCK-BR were increased in gastric cancer tissues and adjacent mucosa compared with tumor-free tissues, but not significantly increased in adjacent mucosa and gastric cancer tissues compared with gastric cancer tissues.CONCLUSION: Overexpression of IGF-1/IGF-1R and gastrin/CCK-BR promotes the disorderly proliferation of gastric mucosa epithelia and it is of great significance in the carcinogenesis and development of gastric carcinoma.

Effects of different Helicobacter pylori culture filtrates on growth of gastric epithelial cells

AIM:To study the effects of different Helicobacter pylori(H pylori) culture filtrates on growth of gastric epithelial cells. METHODS:Broth culture filtrates of H pylori were prepared. Gastric epithelial cells were treated with the filtrates,and cell growth was determined by growth curve and flow cytometry. DNA damage of gastric epithelial cells was measured by single-cell microgel electrophoresis. RESULTS:Gastric epithelial cells proliferated actively when treated by CagA-gene-positive broth culture filtrates,and colony formation reached 40%. The number of cells in S phase increased compared to controls. Comet assay showed 41.2% comet cells in GES-1 cells treated with CagA-positive filtrates(P < 0.05) . CONCLUSION:CagA-positive filtrates enhance the changes in morphology and growth characteristics of human gastric epithelial tumor cells. DNA damage maybe one of the mechanisms involved in the growth changes.

Expression of ATP7B in human gastric cardiac carcinomas in comparison with distal gastric carcinomas

AIM： To analyze expression of ATP7B in gastric cardiac adenocarcinomas, its clinicopathologic significance, in comparison with distal gastric adenocarcinomas. METHODS： Immunohistochemical avidin-biotin peroxidase complex method was applied to detect the expression of ATP7B in 49 cases of cardiac carcinomas, the corresponding adjacent non-neoplastic epithelium and 55 cases of distal gastric carcinomas. RESULTS： The proportion of ATP7B positive samples in gastric cardiac carcinomas （51.0%, 25 of 49） was significantly higher than that in the corresponding adjacent non-neoplastic epithelium （22.4%, 11 of 49） （P = 0.003）. ATP7B expression in poorly differentiated gastric cardiac carcinomas was significantly higher than that in well/moderately differentiated gastric cardiac carcinomas （P = 0.030）. ATP7B expression in gastric cardiac carcinomas was independent of age, tumor size, nodal stage and metastasis status. ATP7B protein was detected in 30.9% （17/55 cases） of distal gastric carcinomas, markedly lower than that in gastric cardiac carcinomas （P = 0.037）. CONCLUSION： ATP7B protein is frequently overexpressecl in gastric cardiac carcinomas, and correlated with the differentiation of cardiac carcinoma. ATP7B expression in gastric cardiac carcinomas is significantly higher than that in distal gastric carcinomas, which might partially explain the difference of chemotherapy response and prognosis between these two gastric carcinomas.

Relationship between p-catenin expression and epithelial cell proliferation in gastric mucosa with intestinal metaplasia

AIM： To investigate β-catenin expression in patients with intestinal metaplasia, and to look for a possible relationship between β-catenin expression and either epithelial proliferation values or Helicobacter pylori （ H pylori） infection.METHODS： Twenty patients with complete type intestinal metaplasia were studied. β-Catenin expression and epithelial cell proliferation in antral mucosa were assessed using an immunohistochemical analysis. H pylori infection was detected by histology and a rapid urease test.RESULTS： Reduced β-catenin expression on the surface of metaplastic cells was detected in 13 （65%） out of 20 patients. Moreover, in eight （40%） patients intranuclear expression of β-catenin was found. When patients were analyzed according to H pylori infection, the prevalence of both β-catenin reduction at the cell surface and its intranuclear localization did not significantly differ between infected and uninfected patients. Cell proliferation was higher in patients with intranuclear β-catenin expression as compared to the remaining patients, although the difference failed to reach the statistical significance （36±8.9 vs 27.2±11.4, P= 0.06）. On the contrary, a similar cell proliferation value was observed between patients with reduced expression of β-catenin on cell surface and those with a normal expression （28.1±11.8 vs 26.1±8.8, P= 0.7）.H pylori infection significantly increased cell proliferation （33.3±10.2% vs 24.6±7.4% , respectively, P= 0.04）.CONCLUSION： Both cell surface reduction and intranuclear accumulation of β-catenin were detected in intestinal metaplasia. The intranuclear localization of β-catenin increases cell proliferation. H pylori infection does not seem to play a direct role in β-catenin alterations, whilst it significantly increases cell proliferation.

H pylori receptor MHC class Ⅱ contributes to the dynamic gastric epithelial apoptotic response

AIM： TO investigate the role of MHC class Ⅱ in the modulation of gastric epithelial cell apoptosis induced by H pylori infection. METHODS： After stimulating a human gastric epithelial cell line with bacteria or agonist antibodies specific for MHC class Ⅱ and CD95, the quantitation of apoptotic and anti-apoptotic events, including caspase activation, BCL-2 activation, and FADD recruitment, was performed with a fluorometric assay, a cytometric bead array, and confocal microscopy, respectively. RESULTS： Pretreatment of N87 cells with the anti-MHC class Ⅱ IgM antibody RFD1 resulted in a reduction in global caspase activation at 24 h of H pylori infection. When caspase 3 activation was specifically measured, crosslinking of MHC class Ⅱ resulted in a marked reduced caspase activation, while simple ligation of HHC class Ⅱ did not. Crosslinking of HHC class Ⅱ also resulted in an increased activation of the anti-apoptosis molecule BCL-2 compared to simple ligation. Confocal microscope analysis demonstrated that the pretreatment of gastric epithelial cells with a crosslinking anti-HHC class Ⅱ IgH blocked the recruitment of FADD to the cell surface. CONCLUSION： The results presented here demonstrate that the ability of MHC class Ⅱ to modulate gastric epithelial apoptosis is at least partially dependent on its crosslinking. Furthermore, while previous research has demonstrated that MHC class Ⅱ signaling can be proapoptotic during extended ligation, we have shown that the crosslinking of this molecule has anti-apoptotic ef-fects during the earlier time points of Hpylori infection. This effect is possibly mediated by the ability of MHC class Ⅱ to modulate the activation of the pro-apoptotic receptor Fas by blocking the recruitment of the accessory molecule FADD, and this delay in apoptosis induction could allow for prolonged cytokine secretion by Hpyloriinfected gastric epithelial cells.

Helpfulness of the combination of acetic acid and FICE in the detection of Barrett's epithelium and Barrett's associated neoplasias

AIM:To investigate the mucosal morphology in Barrett's oesophagus by chromo and magnifying endoscopy.METHODS:A prospective pilot study at a tertiary medical centre was conducted to evaluate the use of acetic acid pulverisation combined with virtual chromoendoscopy using Fujinon intelligent chromoendoscopy(FICE) for semiological characterization of the mucosal morphology in Barrett's oesophagus and its neoplastic complications.Upper endoscopy using high definition whitelight,2% acid acetic pulverisation and FICE with high definition videoendoscopy were performed in 20 patients including 18 patients who presented with aspects of Barrett's oesophagus at endoscopy examination.Two patients used as controls had normal endoscopy and histological results.Prospectively,videos were watched blind from histological results by three trained FICE technique endoscopists.RESULTS:The videos of patients with high-grade dysplasia showed an irregular mucosal pattern in 14% using high definition white light endoscopy and in 100% using acid acetic-FICE combined.Videos did not identify irregular vascular patterns using high definition white light endoscopy,while acid acetic-FICE combined visualised one in 86% of cases.CONCLUSION:Combined acetic acid and FICE is a promising method for screening high-grade dysplasia and early cancer in Barrett's oesophagus.

Epithelial cell proliferation and glandular atrophy in lymphocytic gastritis: Effect of H pylori treatment

AIM:Lymphocytic gastritis is commonly associated with Helicobacter pylori infection.The presence of glandular atrophy and foveolar hyperplasia in lymphocytic gastritis suggests abnormalities in cell proliferation and differentiation, forming a potential link with the suspected association with gastric cancer.Our aim was to compare epibhelial cell proliferation and morphology in H pylori associated lymphocytic gastritis and H pylori gastritis without features of lymphocytic gastritis, and to evaluate the effect of H pylori treatment. METHODS:We studied 14 lymphocytic gastritis patients with H pylori infection.For controls,we selected 14 matched dyspeptic patients participating in another treatment trial whose H pylori infection had successfully been eradicated. Both groups were treated with a triple therapy and followed up with biopsies for 6-18 months (patients) or 3 months (controls).Blinded evaluation for histopathological features was carried out.To determine the cell proliferation index, the sections were labeled with Ki-67 antibody. RESULTS:Before treatment,lymphocytic gastritis was characterized by foveolar hyperplasia (P=0.001) and glandular atrophy in the body (P=0.008),and increased proliferation in both the body (P=0.001) and antrum (P=0.002).Proliferation correlated with foveolar hyperplasia and inflammation activity.After eradication therapy,the number of intraepithelial lymphocytes decreased in the body (P=0.004) and antrum (P=0.065),remaining higher than in controls (P<0.001).Simultaneously,the proliferation index decreased in the body from 0.38 to 0.15 (P=0.043),and in the antrum from 0.34 to 0.20 (P=0.069),the antral index still being higher in lymphocytic gastritis than in controls (P=0.010). Foveolar hyperplasia and glandular atrophy in the body improved (P=0.021),reaching the non-LG level.CONCLUSION: In lymphocytic gastritis, excessive epithelialcell proliferation is predominantly present in the body, where it associates with foveolar hyperplasia and glandular atrophy. These characteristic changes of lymphocytic gastritis are largely related to H pylori infection, as shown by their improvement after eradication. However, some residualdeviation was still seen in lymphocytic gastritis, indicating either an abnormally slow improvement or the presence of some persistent abnormality.

Comparative genomic study of gastric epithelial cells co-cultured with Helicobacter pylori

AIM:To identify genes potentially involved in Helicobacter pylori(H.pylori)-induced gastric carcinogenesis.METHODS:GES-1 cells were co-cultured with H.pylori strains isolated from patients with gastric carcinoma(GC,n = 10) or chronic gastritis(CG,n = 10) for in vitro proliferation and apoptosis assays to identify the most and least virulent strains.These two strains were cagA-genotyped and used for further in vivo carcinogenic virulence assays by infecting Mongolian gerbils for 52 wk,respectively;a broth free of H.pylori was lavaged as control.Genomic profiles of GES-1 cells cocultured with the most and least virulent strains were determined by microarray analysis.The most differentially expressed genes were further verified using quantitative real-time polymerase chain reaction in GES-1cells infected with the most and least virulent strains,and by immunohistochemistry in H.pylori positive CG,precancerous diseases,and GC biopsy specimens in an independent experiment.RESULTS:GC-derived H.pylori strains induced a potent proliferative effect in GES-1 cells in co-culture,whereas CG-derived strains did not.The most(from a GC patient) and least(from a CG patient) virulent strains were cagA-positive and negative,respectively.At week 52,CG,atrophy,metaplasia,dysplasia,and GC were observed in 90.0%,80.0%,80.0%,90%,and 60.0%,respectively,of the animals lavaged with the most virulent strain.However,only mild CG was observed in 90% of the animals lavaged with the least virulent strain.On microarray analysis,800 differentially expressed genes(49 up-and 751 down-regulated),involving those associated with cell cycle regulation,cell apoptosis,cytoskeleton,immune response,and substance and energy metabolisms,were identified in cells co-cultured with the most virulent strain as compared with those co-cultured with the least virulent strain.The six most differentially expressed genes(with a betweenness centrality of 0.1-0.2) were identified among the significant differential gene profile network,including JUN,KRAS,BRCA1,SMAD2,TRAF1,and HDAC6.Quantitative real-time polymerase chain reaction analyses verified that HDAC6 and TRFA1 mRNA expressions were significantly more up-regulated in GES-1 cells cocultured with the most virulent strain than in those cocultured with the least virulent strain.Immunohistochemistry of gastric mucosal specimens from H.pyloripositive patients with CG,intestinal metaplasia(IM),dysplasia,and GC showed that moderately positive and strongly positive HDAC6 expression was detected in 21.7% of CG patients,30.0% of IM patients,54.5% of dysplasia patients,and 77.8% of GC patients(P < 0.001).The up-regulation of TRAF1 expressions was detected in 34.8%,53.3%,72.7%,and 88.9% specimens of CG,IM,dysplasia,and GC,respectively(P < 0.001).CONCLUSION:The overexpression of HDAC6 and TRAF1 in GES-1 cells co-cultured with the GC-derived strain and in H.pylori-positive dysplasia and GC suggests that HDAC6 and TRAF1 may be involved in H.pyloriinduced gastric carcinogenesis.

Long-term omeprazole and esomeprazole treatment does not significantly increase gastric epithelial cell proliferation and epithelial growth factor receptor expression and has no effect on apoptosis and p53 expression

AIM： To study the effect of proton pump inhibitor （PPI） treatment on patients with reflux esophagitis and its in vivo effect on apoptosis, p53- and epidermal growth factor receptor （EGFR） expression. METHODS： After informed consent was obtained, gastric biopsies of the antrum were taken from patients with reflux oesophagitis prior to and after 6 mo of 20 mg omeprazole （n = 24） or 40 mg esomeprazole （n = 22） therapy. Patients did not take any other medications known to affect the gastric mucosa. All patients were Helicobacter pylori negative as confirmed by rapid urease test and histology, respectively. Cell proliferation, apoptosis, EGFR, and p53 expression were measured by immunohistochemical techniques. At least 600 glandular epithelial cells were encountered and results were expressed as percentage of total cells counted. Was considered statistically significant. RESULTS： Although there was a trend towards increase of cell proliferation and EGFR expression both in omeprazole and esomeprazole treated group, the difference was not statistically significant. Neither apoptosis nor p53 expression was affected. CONCLUSION： Long-term PPI treatment does not significantly increase gastric epithelial cell proliferation and EGFR expression and has no effect on apoptosis and p53 expression.