OBJECTIVE: To investigate the differentially expressed genes between gastric cancer and normal gastric mucosa by bioinformatics analysis, identify the important gene participating in the occurrence and progression of gastric cancer, and predict the functions of these genes. METHODS: The gene expression microarray data GSE100935 (including 18 gastric cancer samples and normal gastric mucosal tissues) downloaded from the GEO expression profile database were analyzed using Morpheus to obtain the differentially expressed genes in gastric cancer, and a cluster analysis heat map was constructed. The online database UALCAN was used to obtain the expression levels of these differentially expressed genes in gastric cancer and normal gastric mucosa. The prognostic value of the differentially expressed genes in gastric cancer was evaluated with Kaplan-Meier survival analysis. GO functional enrichment analysis was performed using Fun-Rich software, and the STRING database was exploited to establish a PPI network for the differentially expressed genes. RESULTS: A total of 45119 differentially expressed genes were identified from GSE100935 microarray data. Analysis with UALCAN showed an obvious high expression of EXD3 gene in gastric cancer, and survival analysis suggested that a high expression level of EXD3 was associated with a poorer prognosis of the patients with gastric cancer. GO functional enrichment analysis found that the differentially expressed genes in gastric cancer were involved mainly in the regulation of nucleotide metabolism and the activity of transcription factors in the cancer cells. CONCLUSIONS EXD3 may be a potential oncogene in gastric cancer possibly in relation to DNA damage repair. The up-regulation of EXD3 plays an important role in the development and prognosis of gastric cancer, and may serve as an important indicator for prognostic evaluation of the patients.
Computational Biology ; Databases, Genetic ; Exonucleases ; genetics ; Gastric Mucosa ; chemistry ; enzymology ; Gene Expression Profiling ; Gene Expression Regulation, Neoplastic ; Humans ; Neoplasm Proteins ; genetics ; Prognosis ; Stomach Neoplasms ; enzymology ; genetics ; mortality

BACKGROUND/AIMS: The aims of this study were to investigate whether a broccoli sprout extract containing sulforaphane (BSES) inhibited the Helicobacter pylori infection density and exerted an antioxidative effect on gastric mucosal damage. METHODS: The enrolled subjects were randomized in a double-blinded manner into three groups. Finally, 33 H. pylori (+) BSES treatment subjects (group A), 28 H. pylori (+) placebo subjects (group B), and 28 H. pylori (-) BSES treatment subjects (group C) were studied. H. pylori infection density was indirectly quantified by a 13C-urea breath test (UBT), and the ammonia concentration in gastric juice aspirates was measured through gastroscopic examination. Malondialdehyde (MDA), an oxidative damage biomarker, and reduced glutathione (GSH), an antioxidant biomarker, were measured in the gastric mucosa by an enzyme-linked immunosorbent assay. RESULTS: BSES treatment did not significantly affect the UBT values or ammonia concentration in group A (p=0.634 and p=0.505, respectively). BSES treatment did significantly reduce mucosal MDA concentrations in group A (p<0.05) and group C (p<0.001), whereas the gastric mucosal GSH concentrations did not differ before and after treatment in any of the groups. CONCLUSIONS: BSES did not inhibit the H. pylori infection density. However, BSES prevented lipid peroxidation in the gastric mucosa and may play a cytoprotective role in H. pylori-induced gastritis.
Adult ; Ammonia/metabolism ; Antioxidants/*pharmacology ; Biomarkers/analysis ; Brassica/*chemistry ; Breath Tests ; Double-Blind Method ; Enzyme-Linked Immunosorbent Assay ; Female ; Gastric Juice/enzymology ; Gastric Mucosa/*drug effects/metabolism ; Glutathione/analysis ; Helicobacter Infections/*drug therapy ; *Helicobacter pylori ; Humans ; Isothiocyanates/*pharmacology ; Lipid Peroxidation/*drug effects ; Male ; Malondialdehyde/analysis ; Middle Aged ; Plant Extracts/chemistry/*pharmacology ; Urea

BACKGROUND/AIMS: The prevalence of peptic ulcer disease has not decreased mainly due to an increase in the use of NSAIDs. This study was conducted in order to determine whether a chronic NSAID-induced gastric inflammation model could be established by repeated administration of NSAID. METHODS: Indomethacin (10 mg/kg) was administered once per week for six weeks in 8- and 26-week rats and animals were sacrificed every week after administration. Gross ulcer index, histologic damage index, myeloperoxidase (MPO) activity, and mucus (glucosamine) levels were measured. Small bowel damage was also evaluated. RESULTS: Gross gastric damage index showed a peak level at three weeks and then decreased slowly in the 26-week indomethacin group. Gastric mucosal glucosamine level increased in both the 8-week (p=0.038) and 26-week groups (p=0.007). In addition, gastric mucosal MPO level decreased in the 8-week group (p=0.018) but did not show a decrease in the 26-week group. Small bowel damage began to occur at three weeks during the schedule and eight of 36 rats (22.2%) died due to perforation or peritonitis of the small bowel in the 8- and 26-week indomethacin groups, respectively. CONCLUSIONS: Due to gastric adaptation and small bowel damage, repeated administration of NSAID to experimental animals may not be an adequate method for establishment of the chronic gastric inflammation model.
Animals ; Anti-Inflammatory Agents, Non-Steroidal/*toxicity ; Disease Models, Animal ; Gastric Mucosa/*drug effects/enzymology/pathology ; Glucosamine/metabolism ; Indomethacin/*toxicity ; Intestine, Small/*drug effects/pathology ; Male ; Peroxidase/metabolism ; Rats ; Rats, Sprague-Dawley ; Time Factors

BACKGROUND/AIMS: The prevalence of peptic ulcer disease has not decreased mainly due to an increase in the use of NSAIDs. This study was conducted in order to determine whether a chronic NSAID-induced gastric inflammation model could be established by repeated administration of NSAID. METHODS: Indomethacin (10 mg/kg) was administered once per week for six weeks in 8- and 26-week rats and animals were sacrificed every week after administration. Gross ulcer index, histologic damage index, myeloperoxidase (MPO) activity, and mucus (glucosamine) levels were measured. Small bowel damage was also evaluated. RESULTS: Gross gastric damage index showed a peak level at three weeks and then decreased slowly in the 26-week indomethacin group. Gastric mucosal glucosamine level increased in both the 8-week (p=0.038) and 26-week groups (p=0.007). In addition, gastric mucosal MPO level decreased in the 8-week group (p=0.018) but did not show a decrease in the 26-week group. Small bowel damage began to occur at three weeks during the schedule and eight of 36 rats (22.2%) died due to perforation or peritonitis of the small bowel in the 8- and 26-week indomethacin groups, respectively. CONCLUSIONS: Due to gastric adaptation and small bowel damage, repeated administration of NSAID to experimental animals may not be an adequate method for establishment of the chronic gastric inflammation model.
Animals ; Anti-Inflammatory Agents, Non-Steroidal/*toxicity ; Disease Models, Animal ; Gastric Mucosa/*drug effects/enzymology/pathology ; Glucosamine/metabolism ; Indomethacin/*toxicity ; Intestine, Small/*drug effects/pathology ; Male ; Peroxidase/metabolism ; Rats ; Rats, Sprague-Dawley ; Time Factors

BACKGROUND/AIMS: Doublecortin and CaM kinase-like-1 (DCAMKL1) is a marker of stem cells expressed predominantly in the crypt base in the intestine. However, DCAMKL1-positive cells have been shown to be differentiated tuft cells rather than quiescent progenitors. Tuft cells are the only epithelial cells that express cyclooxygenase 2 (COX-2) in the normal intestinal epithelium. We previously generated Cdx2-transgenic mice as model mice for intestinal metaplasia and gastric carcinoma. In the current study, we investigated the association between COX-2 and DCAMKL1 in gastric carcinoma. METHODS: We examined the association between COX-2 and DCAMKL1 expression in gastric carcinomas in clinical samples (early gastric well-differentiated adenocarcinoma) and Cdx2-transgenic mice; and the DCAMKL1-transgenic mouse stomach using immunohistochemistry and quantitative real-time polymerase chain reaction. RESULTS: The COX-2-expressing cells were scattered, not diffusely expressed, in gastric carcinomas from humans and Cdx2-transgenic mice. DCAMKL1-positive cells were also scattered in the gastric carcinomas, indicating that tuft cells could still be present in gastric carcinoma. COX-2 was expressed in DCAMKL1-positive tuft cells in Cdx2- and DCAMKL1-transgenic mouse stomachs, whereas the Sox9 transcription factor was ubiquitously expressed in gastric carcinomas, including COX-2-positive cells. CONCLUSIONS: COX-2 is expressed in DCAMKL1-expressing quiescent tuft cells in gastric carcinoma.
Adenocarcinoma/metabolism ; Animals ; Cyclooxygenase 2/genetics/*metabolism ; Epithelial Cells/metabolism ; Gastric Mucosa/metabolism ; Humans ; Intestinal Mucosa/cytology/*enzymology/metabolism ; Intracellular Signaling Peptides and Proteins/genetics/*metabolism ; Mice ; Mice, Transgenic ; Protein-Serine-Threonine Kinases/genetics/*metabolism ; SOX9 Transcription Factor/genetics/metabolism ; Stomach Neoplasms/*enzymology/genetics

OBJECTIVETo investigate the association of AKR1B10 expression in gastric cancer tissues with clinicopathologic features and prognosis of gastric cancer patients.

METHODSReal-time polymerase chain reaction (RT-PCR) was conducted to detect AKR1B10 mRNA expression in gastric cancer and adjacent gastric mucosa tissues (n=36). AKR1B10 protein expression was measured by immunohistochemistry in primary gastric cancer tissues (n=100) and non-tumorous gastric mucosa tissues (n=70).

RESULTSRT-PCR results confirmed that AKR1B10 was significantly down-regulated in gastric cancer tissues compared with that in paired adjacent mucosa [8.3% (3/36) vs. 91.7% (33/36), P=0.000]. Immunohistochemistry revealed that the percentage of AKR1B10 positive specimens in gastric carcinoma was lower than that in normal specimens [33.0% (33/100) vs. 92.9% (65/70), P=0.000]. The frequencies of positive AKR1B10 in patients was significantly correlated with tumor size (P=0.000), invasive depth (P=0.004), lymph node metastasis (P=0.028), distant metastasis (P=0.031) and TNM stages (P=0.000). The 5-year survival rate of positive AKR1B10 group was significantly higher as compared to negative group (60.6% vs. 32.8%, P<0.01).

CONCLUSIONThe down-regulation of AKR1B10 expression in gastric cancer may be associated with the progress of gastric cancer is suggestive of poor prognosis.

Adult ; Aged ; Aged, 80 and over ; Aldehyde Reductase ; genetics ; metabolism ; Female ; Gastric Mucosa ; enzymology ; pathology ; Humans ; Male ; Middle Aged ; Prognosis ; RNA, Messenger ; genetics ; Stomach Neoplasms ; diagnosis ; enzymology ; pathology

Helicobacter pylori (H. pylori) is an important risk factor for chronic gastritis, peptic ulcer, and gastric cancer. Proteinase-activated receptor 2 (PAR2), subgroup of G-protein coupled receptor family, is highly expressed in gastric cancer, and chronic expression of cyclooxygenase-2 (COX-2) plays an important role in H. pylori-associated gastric carcinogenesis and inflammation. We previously demonstrated that H. pylori induced the expression of PAR2 and COX-2 in gastric epithelial cells. Present study aims to investigate whether COX-2 expression induced by H. pylori in Korean isolates is mediated by PAR2 via activation of Gi protein and Src kinase in gastric epithelial AGS cells. Results showed that H. pylori-induced COX-2 expression was inhibited in the cells transfected with antisense oligonucleotide for PAR2 or treated with Gi protein blocker pertussis toxin, Src kinase inhibitor herbimycin A and soybean trypsin inbitor, indicating that COX-2 expression is mediated by PAR2 through activation of Gi protein and Src kinase in gastric epithelial cells infected with H. pylori in Korean isolates. Thus, targeting the activation of PAR2 may be beneficial for prevention or treatment of gastric inflammation and carcinogenesis associated with H. pylori infection.
Benzoquinones/*pharmacology ; Cell Line, Tumor ; Cyclooxygenase 2/genetics/*metabolism ; Epithelial Cells/enzymology/metabolism/microbiology ; GTP-Binding Protein alpha Subunits, Gi-Go/metabolism ; Gastric Mucosa/enzymology/metabolism/*microbiology ; *Helicobacter pylori ; Humans ; Lactams, Macrocyclic/*pharmacology ; Oligonucleotides, Antisense ; Pertussis Toxin/*pharmacology ; RNA, Messenger/metabolism ; Receptor, PAR-2/*physiology ; src-Family Kinases/metabolism

OBJECTIVECytotoxin-associated protein (CagA) of H. pylori has been confirmed to be closely associated with gastric inflammation and tumorigenesis, but the mechanism behind it is little understood. In this study, we try to determine roles of CagA(+) strain in activating PI3K/Akt1 signaling pathway, and affecting expression of p21(WAF1/CIP1) and p27(KIP1), and also in releasing IL-8 in host cells.

METHODSAkt1 phosphorylation and IL-8 levels of CagA(+) and CagA⁻ strain infected AGS cells were detected by ELISAs. Two quantitative RT-PCRs were established to measure p21(WAF1/CIP1) and p27(KIP1) mRNA levels in the CagA(+) and CagA⁻ strain infected cells. LY294002, an inhibitor of PI3K/Akt pathway, was used to define effect of the pathway in IL-8 release.

RESULTSCagA(+) strain could induce an obvious elevation of Akt1 phosphorylation in the infected AGS cells while CagA? strain failed to do so. The CagA(+) H. pylori strain infected AGS cells showed significant drops both in p21(WAF1/CIP1) and p27(KIP1) mRNA levels, whereas the CagA⁻ H. pylori strain caused a remarkable increase in p21(WAF1/CIP1) mRNA without affecting p27(KIP1) gene transcription in the AGS cells. Both the CagA(+) and CagA⁻ H. pylori strains enabled AGS cells to produce close elevated levels of IL-8, and the LY294002 block resulted in unexpected elevations of IL-8 levels.

CONCLUSIONSCagA can activate PI3K/Akt1 pathway that plays an inhibitory role in IL-8 release in H. pylori infected AGS cells. Activation of PI3K/Akt1 pathway and subsequent negative regulation of p21(WAF1/CIP1) and p27(KIP1) expression might be involved in CagA-associated carcinogenesis.

Antigens, Bacterial ; genetics ; physiology ; Bacterial Proteins ; genetics ; physiology ; Cell Line ; Cyclin-Dependent Kinase Inhibitor p21 ; biosynthesis ; Cyclin-Dependent Kinase Inhibitor p27 ; Gastric Mucosa ; cytology ; enzymology ; microbiology ; Helicobacter pylori ; metabolism ; pathogenicity ; physiology ; Humans ; Interleukin-8 ; secretion ; Intracellular Signaling Peptides and Proteins ; metabolism ; Phosphatidylinositol 3-Kinases ; metabolism ; Phosphorylation ; Proto-Oncogene Proteins c-akt ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Signal Transduction ; Transcription, Genetic ; Virulence

BACKGROUND/AIMS: The cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), the proteins that have the role in the gastric carcinogenesis, are stimulated by H. pylori infection in the gastric mucosa. The aim of this study was to evaluate the expression of COX-2 and iNOS proteins one year after the eradication of H. pylori. METHODS: Gastric antral mucosa from fifty eight patients with chronic gastritis who were all infected with H. pylori was examined for the expression of COX-2 and iNOS proteins before and one year after the eradication of H. pylori by immunohistochemical stain. RESULTS: COX-2 and iNOS proteins were expressed in the epithelial cells and interstitial inflammatory cells of gastric mucosa. Percent expressions of COX-2 and iNOS were significantly decreased one year after the eradication in the patients with cured infection, but not in those having persistent H. pylori. COX-2 and iNOS expressions were well correlated with H. pylori density, acute and chronic inflammation of gastric mucosa. CONCLUSIONS: The eradication of H. pylori can decrease the expression of COX-2 and iNOS in the gastric mucosa in long-term period. This seems to be due to the removal of H. pylori itself and related regression of gastric inflammation.
Cyclooxygenase 2/immunology/*metabolism ; Drug Therapy, Combination ; Gastric Mucosa/*enzymology ; Helicobacter Infections/drug therapy ; *Helicobacter pylori ; Humans ; Nitric Oxide Synthase Type II/immunology/*metabolism ; Time Factors

BACKGROUNDWe investigated the role in electrical stimulations of paraventricular nucleus (PVN) on gastric mucosal cells and the activity of mitogen-activated protein kinases (MAPKs) family members induced by gastric ischemia-reperfusion (GI-R). And we elucidated the molecular mechanisms of the protection of PVN from GI-R injuries.

METHODSSprague-Dawley rats were divided randomly into 4 groups: Group I, the sham-operated GI-R control group; Group II, the sham-operated electrical stimulations to PVN + sham-operated GI-R control group; Group III, the GI-R group; and Group IV, the electrical stimulations to PVN + GI-R group. In all of the experiments, the PVN was stimulated prior to the induction of GI-R. The GI-R model was established by clamping the celiac artery for 30 minutes to induce ischemia and then was released to allow reperfusion for 30 minutes, 1 hour, 3 hours and 6 hours, respectively. The gastric mucosal cellular apoptosis, proliferation, and the expression and activity of MAPKs protein were observed by immunohistochemistry and Western blotting, respectively.

RESULTSCompared with the GI-R group, the application of electrical stimulations in the PVN significantly depressed gastric mucosal cellular apoptosis and enhanced gastric mucosal cellular proliferation following the 30-minute, 1-hour and 3-hour intervals of reperfusion; it also promoted the activation of p-ERK during the early phase of reperfusion but inhibited the activation of p-JNK1/2 and p-p38 following the 30-minute, 1-hour and 3-hour intervals of reperfusion.

CONCLUSIONSThe protection of PVN against GI-R injuries may attribute to the inhibition of apoptosis and the promotion of the proliferation of gastric mucosal cells during GI-R. This protective effect is mediated by activating the ERK pathway and depressing the JNK, p38 MAPK pathways of the gastric mucosal cells.

Animals ; Apoptosis ; Cell Proliferation ; Electric Stimulation ; Extracellular Signal-Regulated MAP Kinases ; physiology ; Gastric Mucosa ; blood supply ; enzymology ; pathology ; JNK Mitogen-Activated Protein Kinases ; physiology ; MAP Kinase Signaling System ; physiology ; Male ; Paraventricular Hypothalamic Nucleus ; physiology ; Phosphorylation ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; prevention & control ; p38 Mitogen-Activated Protein Kinases ; physiology