Fibroblast-derived HB-EGF promotes Cdx2 expression in esophageal squamous cells.

The molecular basis of attaining columnar phenotype in Barrett's esophagus is poorly understood. One hypothesis states that factors locally produced by cells of mesenchymal origin in chronic reflux esophagitis induce metaplastic transformation. This study was performed to elucidate the factors secreted from fibroblasts that cause columnar phenotype in adjacent squamous epithelium.

In vivo evidence for the role of RegI in gastric regeneration: transgenic overexpression of RegI accelerates the healing of experimental gastric ulcers.

On the basis of its temporal and spatial pattern of expression during the healing of gastric ulcers, RegI is implied to be a key growth factor governing the gastric progenitor cell proliferation, which is fundamental for reconstruction of the gastric tissue; however, there is no direct in vivo evidence. The aim of this study was to use RegI-transgenic (Tg) mice to test the role of RegI protein in the healing of experimentally induced gastric ulcers. The stomachs from 48 pairs of wild-type (Wt) and Tg littermates were examined for gastric erosions after 24 h of water-immersion stress, or, 6, 12, 18 and 24 h after oral administration of HCl/ethanol.

MFG-E8 attenuates intestinal inflammation in murine experimental colitis by modulating osteopontin-dependent alphavbeta3 integrin signaling.

MFG-E8 (milk fat globule-epidermal growth factor 8) deficiency is strongly associated with acquisition of immune-mediated disorders due to the loss of tissue homeostasis. However, comparatively little is known regarding its functions in gastrointestinal tract disorders, in which immune homeostasis is a major concern. Herein, we report altered MFG-E8 expression in inflamed colons during the acute phase of murine experimental colitis and found that treatment with recombinant MFG-E8, but not its arginine-glycine-aspartate mutant counterpart, ameliorated colitis by reducing inflammation and improving disease parameters.

Decoy oligodeoxynucleotide targeting activator protein-1 (AP-1) attenuates intestinal inflammation in murine experimental colitis.

Various therapies are used for inflammatory bowel diseases (IBD), though none seem to be extremely effective. AP-1 is a major transcription factor that upregulates genes involved in immune and proinflammatory responses. We investigated decoy oligodeoxynucleotide (ODN) targeting AP-1 to prevent dextran sulfate sodium (DSS)-induced colitis in mice.

Prolactin induces MFG-E8 production in macrophages via transcription factor C/EBPbeta-dependent pathway.

The lactogenic hormone prolactin (PRL) regulates milk protein gene expression in mammary glands. To maintain homeostatic balance in the body, milk fat globule epidermal growth factor 8 (MFG-E8) is vital for phagocytic clearance of apoptotic cells. We investigated the effects of PRL on MFG-E8 expression in macrophages by evaluating its promoter function.

REG Ialpha protein expression in Barrett's esophagus.

Background And Aim: Accelerated cellular proliferation in Barrett's esophagus has been implicated in Barrett's elongation and malignant transformation. Therefore, growth factors may play important roles in the pathophysiology of Barrett's esophagus. Regenerating gene (REG), an epithelial growth factor, has been reported to link mucosal inflammation and subsequent carcinogenesis in the gastrointestinal tract.

Therapeutic targeting of toll-like receptors in gastrointestinal inflammation.

Toll-like receptors (TLRs) are sensors of microbial products that initiate host defense responses in multicellular organisms. They are mainly linked to innate immunity and bridging to adaptive immunity, signaling through different TLRs responsible for a wide range of biological responses. The intracellular signaling pathways through Toll/interleukin-1 receptor (IL-1R) domains result in recruitment of the cytoplasmic adaptor molecules, with subsequent activation of a signaling cascade leading to nuclear factor-kappa B (NF-kappaB).

Increased expression of midkine in the rat colon during healing of experimental colitis.

Midkine (MK) is a unique growth and differentiation factor that modulates the proliferation and migration of various cells; however, little is known regarding its relationship to intestinal diseases. The aim of this study was to investigate MK expression and its role in dextran sulfate sodium (DSS)-induced colitis in rats. The expressions of MK, receptor-like protein-tyrosine phosphatase (RPTP)-beta, and proinflammatory cytokines were examined in rat colonic tissues after the development of DSS-induced colitis using Northern blotting, immunohistochemistry, and laser-capture microdissection (LCM) coupled with RT-PCR.

A Japanese case of eosinophilic esophagitis.

Eosinophilic esophagitis (EE) is a rarely diagnosed condition involving eosinophilic infiltration of the esophageal mucosa. Here we present a case of EE in a 69-year-old Japanese man, who presented with abdominal pain, appetite loss, and a history of bronchial asthma. Laboratory findings included peripheral eosinophilia and an increased serum immunoglobulin E level.

Epithelial toll-like receptor 5 is constitutively localized in the mouse cecum and exhibits distinctive down-regulation during experimental colitis.

We recently demonstrated that the pattern recognition receptors (PRRs) toll-like receptor 2 (TLR2), TLR4, and CD14 are expressed in mouse colonic epithelium in a compartmentalized manner. Here we report the localization of TLR5, the receptor for bacterial flagellin, and its distinctive down-regulation during experimental colitis. Guts from normal BALB/c mice and those with dextran sodium sulfate (DSS)-induced colitis were compared.

RNA polymerase II mediated transcription from the polymerase III promoters in short hairpin RNA expression vector.

RNA polymerase III promoters of human ribonuclease P RNA component H1, human U6, and mouse U6 small nuclear RNA genes are commonly used in short hairpin RNA (shRNA) expression vectors due their precise initiation and termination sites. During transient transfection of shRNA vectors, we observed that H1 or U6 promoters also express longer transcripts enough to express several reporter genes including firefly luciferase, green fluorescent protein EGFP, and red fluorescent protein JRed. Expression of such longer transcripts was augmented by upstream RNA polymerase II enhancers and completely inhibited by downstream polyA signal sequences.

Interleukin-8 regulates expression of Reg protein in Helicobacter pylori-infected gastric mucosa.

Background & Aim: Chronic inflammation induced by Helicobacter pylori infection is closely associated with epithelial cell proliferation and apoptosis, which are related to cellular turnover in gastric mucosa. Reg protein is a regenerating gene product and a potent growth factor for gastric mucosal cells, however, little is known regarding its association with the pathogenesis of H. pylori infection.

Peroxisome proliferator-activated receptor gamma-dependent and -independent growth inhibition of gastrointestinal tumour cells.

Peroxisome proliferator-activated receptor gamma (PPARgamma) acts as a ligand-activated transcription factor. Although ligand-induced cellular differentiation and growth inhibition have been mostly studied on human cancers expressing PPARgamma, it is unclear if the transcriptional activation of PPARgamma is the main mechanism of growth inhibition. In this study, we investigated whether there is a link between growth inhibitory effect and transcriptional activation of PPARgamma in several gastrointestinal tumour cell lines.

Essential role of MD-2 in TLR4-dependent signaling during Helicobacter pylori-associated gastritis.

TLR4, a member of pattern recognition receptors, is the main receptor of LPS. MD-2 physically associates with TLR4 on the cell surface and confers LPS responsiveness. Helicobacter pylori LPS is one of the major virulence factors for induction of gastritis.

Reg protein is a unique growth factor of gastric mucosal cells.

In 1984, Reg protein was shown to be stimulated during the regeneration of pancreatic islets. Since then, many Reg-related proteins have been identified in humans and other animals. These Reg-related proteins are classified into four subfamilies according to their amino-acid sequences, but they share a similar structure and physiological function.

Transgenic overexpression of Reg protein caused gastric cell proliferation and differentiation along parietal cell and chief cell lineages.

Reg (regenerating gene product) was originally identified as a growth factor involved in pancreatic regeneration. During the healing course of gastric erosion, Reg expression is highly increased in the enterochromaffin-like (ECL) cells surrounding the ulcer crater, suggesting its role as a regulator of gastric mucosal regeneration. However, there has been no direct in vivo evidence of a growth-promoting role of Reg for the gastric mucosal cells.

Transforming growth factor-alpha directly augments histidine decarboxylase and vesicular monoamine transporter 2 production in rat enterochromaffin-like cells.

For the production and vesicle storage of histamine, Enterochromaffin-like (ECL) cells express histidine decarboxylase (HDC) and vesicular monoamine transporter 2 (VMAT2). Although HDC and VMAT2 show dynamic changes during gastric ulcer healing, the control system of their expression has not been fully investigated. In the present study, we investigated the effect of transforming growth factor-alpha (TGF-alpha) and proinflammatory cytokines on HDC and VMAT2 expression in rat ECL cells.

BRAF and K-ras gene mutations in human pancreatic cancers.

We investigated the frequency of BRAF mutations in human pancreatic cancer specimens to determine its role in the development of pancreatic cancer. Nine pancreatic cancer samples without a K-ras codon 12 mutation and 19 with a K-ras mutation were included in the study. Analyses of the BRAF sequence revealed mutations in exon 15 (V599E) in two cases, both of which also exhibited a K-ras codon 12 mutation.

Strategic compartmentalization of Toll-like receptor 4 in the mouse gut.

Pattern recognition receptors (PRRs), which include the Toll-like receptors (TLRs), are involved in the innate immune response to infection. TLR4 is a model for the TLR family and is the main LPS receptor. We wanted to determine the expression of TLR4 and compare it with that of TLR2 and CD14 along the gastrointestinal mucosa of normal and colitic BALB/c mice.

9-cis retinoic acid enhances the antiviral effect of interferon on hepatitis C virus replication through increased expression of type I interferon receptor.

The concentration of type I interferon receptor (IFN-Rc) in the liver is a crucial factor in determining the efficacy of interferon (IFN) therapy in patients with chronic hepatitis C. Retinoic acids (RAs) can enhance the expression of type I IFN-Rc expression. The aim of this study was to investigate whether RAs increase the anti-hepatitis C virus (HCV) effect of IFN through an increase in IFN-Rc.

Reg protein is overexpressed in gastric cancer cells, where it activates a signal transduction pathway that converges on ERK1/2 to stimulate growth.

Reg is a growth factor with mitogenic effects on pancreatic beta cells and gastric stem cells. To date, there has been no information available on Reg-mediated intracellular signal transduction pathways. The role of Reg in the gastric carcinogenesis is also unknown.

Growth inhibition of esophageal squamous carcinoma cells by peroxisome proliferator-activated receptor-gamma ligands.

The growth of human cancer cells expressing peroxisome proliferator-activated receptor-gamma (PPAR-gamma) has been reported to be inhibited by PPAR-gamma ligands. In esophageal squamous-cell carcinoma cell lines T.T, T.