Abstract: Genetic or epigenetic alterations in Barrett's esophagus (BE) with/without Helicobacter pylori (H. pylori) infection remain unclear. We examined the effects of H. pylori infection on genetic instability (GIN), the CpG island methylation status and a biomarker related to BE carcinogenesis. We analyzed 113 Japanese individuals with endoscopically suspected BE. The patients included, Group CLE (n = 25): no specialized intestinal metaplasia (SIM) in a columnar lined epithelium (control); Group BE (n = 88): all had SIM. Microsatellite instability and a loss of heterozygosity as GIN, the methylation status at hMLH1, E-cadherin, p16 and APC, and immunoreactivity using a monoclonal antibody (mAb) Das-1, which specifically reacts with BE, were evaluated. Nine additional patients with BE were prospectively followed up for 2 years after successful H. pylori eradication. The frequency of GIN, methylation at E-cadherin and APC, and mAb Das-1 reactivity in Group BE was significantly higher than that in Group CLE (p < 0.0001, p < 0.0001 and p < 0.005, and p < 0.0001, respectively). Furthermore, GIN, E-cadherin methylation and mAb Das-1 reactivity showed a significantly higher incidence in patients with H.pylori infection than in those without H. pylori infection (p < 0.01, p < 0.005, and p < 0.01, respectively). Interestingly, the patients from Group BE were observed to change to a stable state of molecular alterations in 60% for GIN, 42.9% for E-cadherin methylation and 55.6% for APC methylation, or a reduction of mAb Das-1 reactivity was noted in 25% following eradication. H. pylori infection may therefore affect these molecular alterations associated with the pathogenesis of BE, to some degree, in the Japanese population.

Abstract: Hedgehog signaling is important in the pathogenesis of pancreatic cancer. Several recent observations suggest the involvement of sonic hedgehog (SHH) in postnatal neovascularization. We identified a novel role for SHH in tumor-associated angiogenesis in pancreatic cancer. Immunohistochemical analysis revealed that patched homolog 1 (PTCH1), both a receptor for and transcriptional target of hedgehog signaling, was expressed in a small fraction of endothelial cells within pancreatic cancer, but not in normal pancreatic tissue. When endothelial progenitor cells (EPC) isolated from human peripheral blood were cultured with supernatant from SHH-transfected 293 cells or pancreatic cancer cells, mRNA levels of vascular endothelial growth factor (VEGF), stromal cell-derived factor-1 and angiopoietin-1 were significantly increased, whereas no such induction was observed in human umbilical vein endothelial cell (HUVEC) and human dermal microvascular endothelial cell (HMVEC). HUVEC tube formation was stimulated when cocultured with EPC, and preconditioning EPC with supernatant from KP-1 N pancreatic cancer cells highly expressing SHH significantly enhanced the effect. The effect was partially attenuated by specific inhibition of SHH with cyclopamine or a neutralizing antibody. These findings suggest that tumor-derived SHH can induce angiogenesis, and this is mediated by its effects on EPC specifically. Targeting SHH would be a novel therapeutic approach that can inhibit not only proliferation of cancer cells but also EPC-mediated angiogenesis.

Abstract: To clarify field cancerization in the stomach by genetic alterations, we studied 83 cases of intestinal-type gastric cancer (GC) and paired intestinal metaplasia (IM) distant from GC and 39 cases of chronic gastritis with IM (CG-IM) for genetic instability (GIN). Microsatellite instability (MSI) and loss of heterozygosity (LOH) were evaluated at 5 microsatellite loci. The incidence of GIN was 21% (8/39) in CG-IM, 48% (40/83) in GC-IM, and 65% (54/83) in GC and showed a significant difference among these 3 categories. By tumor location, MSI showed the highest incidence in GC and GC-IM with the tumor located in the upper third of the stomach. GIN in GC and GC-IM significantly increased with the progression of tumor invasion from mucosal to advanced cancer. GIN, especially LOH, was more frequently detected in cases with vs without lymphatic or vascular invasion and lymph node involvement in GC and GC-IM. The GIN of GC and GC-IM was significantly similar in relation to clinicopathologic features. Biologic detection of GIN in IM may be a surrogate marker for GC risk and for clinical evaluation of malignant potential. The condition is consistent with the hypothesis of field cancerization in the stomach.

Abstract: BACKGROUND: The technical difficulties related to the insertion of a long intestinal tube into the jejunum under fluoroscopy present a considerable problem in patients with an intestinal obstruction. OBJECTIVE: To evaluate the usefulness of endoscopic long intestinal-tube placement with the ultrathin esophagogastroduodenoscope (UT-EGD). DESIGN: A prospective randomized clinical trial was conducted. PATIENTS: Twenty-eight consecutive patients who presented with an intestinal obstruction were included in the study. INTERVENTION: The UT-EGD was inserted nasally into at least the second portion of the duodenum or beyond. After a guidewire was introduced through the working channel, with fluoroscopic guidance, the UT-EGD itself was carefully removed with the guidewire left in place. Next, a hydrophilic intestinal tube was advanced over the guidewire into the jejunum, and then the guidewire was removed. MAIN OUTCOME MEASUREMENTS: Primary end points are the total procedure time, the radiation exposure time, and the rate of complications, all compared with the conventional method. RESULTS: The mean (+/-SD) total procedure time was 18.7 +/- 8.4 minutes for the UT-EGD method and 39.5 +/- 15.0 minutes for the conventional method, with a significant time difference between the 2 methods (P < .0005). The mean (+/-SD) radiation exposure time was also shorter with the UT-EGD method (11.1 +/- 6.0 minutes) than with the conventional method (30.3 +/- 13.7 minutes) (P < .0005). There were no complications, except for mild nasal bleeding with each method. CONCLUSIONS: The UT-EGD method has definite advantages in the placement of a long intestinal tube for patients with an intestinal obstruction in comparison with the conventional method.

Abstract: An 83-year-old woman who was admitted to other hospital, was consulted us because of continuous tarry stool and abdominal fullness. On upper endoscopy, the submucosal tumor from greater curvature of gastric fornix invaginated into the duodenal bulbus, showing so-called "ball valve syndrome (BVS)". As the tumor incarcerted again on the following endoscoopy, she underwent laparoscopic partial gastrectomy. The submucosal tumor was diagnosed histologically as gastrointestinal stromal tumor (GIST) arising from the muscularis mucosae. This is the first report that GIST arising from the muscularis mucosae in gastric fornix showed a BVS.

Abstract: BACKGROUND: Helicobacter pylori related gastric intestinal metaplasia (IM) is considered to be a precancerous lesion. AIMS: To identify the effects of H pylori eradication on K-ras mutations, cell kinetics in IM and histological changes in patients with and without gastric cancers in a one-year prospective study. METHODS: Patients included group A (n = 39), chronic gastritis, and group B (n = 53), intestinal-type early gastric cancer patients who had all undergone endoscopic mucosal resection (n = 25) or surgical resection (n = 28). K-ras codon 12 mutations in IM were examined, followed by DNA sequencing analysis. Proliferating and apoptotic cells were detected with anti-Ki-67 antibody and using the TUNEL method, respectively. RESULTS: The incidence of K-ras mutations in the cancer was only 3.8%. The mutant K-ras in IM was observed more frequently in group A (46.2%) than in group B patients (1.9%) (p<0.005). After eradication, the K-ras mutations significantly declined to 12.8% in group A (p<0.005). The mutation pattern of K-ras codon 12 before eradication was that GGT was mainly changed to AGT (50%) in group A. AGT transformation was not affected by treatment. Apoptosis in IM showed an increase after H pylori eradication in both groups (p<0.05 in group A) although no histological improvement in IM was observed. The monocyte score was significantly higher in group A than in group B (p<0.05); the score improved significantly after eradication. CONCLUSIONS: K-ras mutations in IM do not always play a role in gastric carcinogenesis but cell kinetics, especially apoptosis, in IM may contribute to it. There are early events in K-ras mutations which are influenced by H pylori infection; some mutations may also be selected by eradication. These unstable K-ras mutations in IM may be related to lymphocyte infiltration caused by H pylori infection.

Abstract: Bacteria use quorum-sensing molecules (QSMs) to communicate within as well as across species. However, the effects of QSMs on eukaryotic host cells have received limited attention. We report that the quorum-sensing pentapeptide, competence and sporulation factor (CSF), of the Gram-positive bacterium Bacillus subtilis activates key survival pathways, including p38 MAP kinase and protein kinase B (Akt), in intestinal epithelial cells. CSF also induces cytoprotective heat shock proteins (Hsps), which prevent oxidant-induced intestinal epithelial cell injury and loss of barrier function. These effects of CSF depend on its uptake by an apical membrane organic cation transporter-2 (OCTN2). Thus, OCTN2-mediated CSF transport serves as an example of a host-bacterial interaction that allows the host to monitor and respond to changes in the behavior or composition of colonic flora.

Abstract: BACKGROUND & AIMS: Inducible heat shock proteins (iHsp), Hsp25/27 and Hsp70, play essential roles in protecting cells against stress and, in intestinal mucosal inflammation, potentially lessening the extent and severity of injury. We examined the expression and regulation of iHsp in human and experimental inflammatory bowel diseases (IBD) and in vitro. METHODS: iHsp expression and regulation were assessed in normal and IBD colonic biopsy specimens, IL-10(-/-) mice, and young adult mouse colonic epithelial cells by immunohistochemistry, Western blot, and real-time polymerase chain reaction (PCR). Phosphorylation of double-stranded RNA-dependent protein kinase (PKR) and eukaryotic initiation factor-2alpha (eIF-2alpha) was determined by Western blot. RESULTS: Hsp25/27 and Hsp70 levels were selectively reduced in areas of active mucosal inflammation associated with human IBD and IL-10(-/-) mice with colitis. Wild-type mice treated in vivo with interferon (IFN)-gamma + tumor necrosis factor (TNF)-alpha also demonstrated reduced colonic Hsp25/27 and Hsp70. In young adult mouse colonic epithelial cells, IFN-gamma+TNF-alpha inhibited heat induction of Hsp25/27 and Hsp70, an effect not associated with changes in iHsp messenger RNA or protein half-lives but caused by suppressed de novo iHsp synthesis. IFN-gamma+TNF-alpha cotreatment activated PKR, resulting in phosphorylation and inactivation of eIF-2alpha, an essential factor in protein translation. These effects were not due to induced apoptosis and could be negated by PKR-inhibitor and short interfering RNA to PKR. Increased phosphorylation of PKR and eIF-2alpha were also observed in active IBD tissues. CONCLUSIONS: Mucosal inflammation is associated with iHsp down-regulation, an effect that appears mediated by translational down-regulation by proinflammatory cytokines. In the context of IBD, we propose that this mechanism contributes to the severity, extent, and persistence of inflammation-induced mucosal injury.

Abstract: A major mechanism for apical peptide absorption by small intestine is via the proton-coupled transporter PepT1. PepT1 is expressed at a high level in proximal small intestine, but it is not expressed in the healthy colon. However, in chronic states of intestinal inflammation, such as in Crohn's disease and ulcerative colitis, PepT1 expression in colonic epithelia is increased, serving as a pathway for entry of bacteria-derived molecules such as muramyl dipeptide (MDP) and fMet-Leu-Phe (fMLP). As little is known of how inflammation induces PepT1, we investigated whether or not inflammatory cytokines and mediators such as interleukins (IL)-1beta, IL-2, IL-8, IL-10, tumor necrosis factor-alpha, (TNF-alpha) and interferon-gamma (IFN-gamma ) up-regulate PepT1 activity and expression. Uptake of the PepT1 substrate glycylsarcosine [(3)H]-Gly-Sar was studied in vitro in the human colon carcinoma cell line Caco2/bbe monolayers as well as in vivo in mice injected with cytokines. TNF-alpha and IFN-gamma increased the activity, and total and apical membrane protein expression of PepT1 protein in a concentration- and time-dependent fashion. No changes in PepT1 mRNA were observed, suggesting post-transcriptional regulation. All three cytokines increased PepT1 protein expression in mouse proximal and distal colon but not in jejunum or ileum. TNF-alpha and IFN-gamma, but not IL-1beta, increased Gly-Sar uptake in mouse proximal and distal colon; however, no changes were observed in the small intestine with any cytokine treatment. Whereas neither TNF-alpha nor IFN-gamma increased PepT1 mRNA expression in any segment of the intestine, treatment with IL-1beta increased PepT1 mRNA expression in mouse proximal and distal colon and decreased PepT1 mRNA expression in jejunum and ileum. Since PepT1 transports bacteria-derived peptides, the up-regulation of protein expression and activity observed after treatment with TNF-alpha or IFN-gamma may play a role in activating host responses in involved colon.

Abstract: Spontaneous and complete disappearance of diffuse large B-cell lymphoma (DLBL) of the stomach is extremely rare. Although regression of gastric DLBL after eradication of Helicobacter pylori has recently been reported, we present two consecutive cases of stage I DLBL of the stomach which disappeared after only nonspecific therapy, including histamine 2-receptor antagonist (H2RA); both cases were documented histologically and endoscopically. Both patients were positive for H. pylori, and later received H. pylori eradication therapy. The disease has not recurred after 11 and 6 months, respectively. Our cases suggest that the option of combination therapy with H2RA either with or followed by H. pylori eradication is appropriate for consideration as an initial approach in standard therapy for stage I diffuse large B-cell gastric lymphoma.