Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024623 (gastric cancer)
 36,219 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Gastric infection with Helicobacter pylori activates a mucosal inflammatory response by mononuclear cells and neutrophils that includes expression of cytokines interleukin-1 beta (IL-1 beta), IL-6, tumor necrosis factor alpha, and IL-8. In this study, we analyzed the IL-8 response of human gastric cancer cell lines (Kato III, AGS, and MKN28) to H. pylori infection in vitro. IL-8 mRNA expression was detected by reverse transcription-PCR amplification of RNA extracted from epithelial cells after incubation with different H. pylori wild-type and mutant strains, and IL-8 secretion was measured by an enzyme-linked immunosorbent assay. Exposure to viable H. pylori induced IL-8 mRNA and protein synthesis in all three gastric cell lines but not in nongastric epithelial cell lines. Heat-killed H. pylori and a crude cytotoxin preparation did not induce significant IL-8 secretion. IL-8 mRNA peaked between 2 and 4 h postinfection, and IL-8 protein production was maximal 24 h postinfection. Exposure of gastric carcinoma cells to other gastrointestinal bacteria, such as Pseudomonas aeruginosa, Campylobacter jejuni, and Escherichia coli, but not Campylobacter fetus, induced IL-8 synthesis. Wild-type strains that expressed the vacuolating cytotoxin (Tox+) and a cytotoxin-associated gene (cagA) product (CagA+) induced significantly more IL-8 than did CagA- Tox- strains. However, there was no decrease in IL-8 induction by isogenic mutants of CagA-, Tox-, or Cag- Tox- strains or by a mutant lacking the urease subunits. These results indicate that exposure to H. pylori and other gram-negative organisms that do not colonize the gastric mucosa induces IL-8 production by gastric carcinoma cells in vitro. Although the CagA+ Tox+ phenotype of H. pylori is associated with enhanced IL-8 production by gastric cell lines, other bacterial constituents are clearly essential.
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PMID:Interleukin-8 response of gastric epithelial cell lines to Helicobacter pylori stimulation in vitro. 772 72

In order to evaluate the biological response after intraperitoneal administration of OK-432 and CDDP, we studied the changes of cytokine levels in ascitic fluid. A total of 53 gastric cancer patients were included in this study. OK-432 20KE was administered in 7 patients and CDDP was administered in 4 patients intraperitoneally during operation. The IL-6, IL-8, TNF-alpha and sTNF RI levels in ascitic fluid were measured from 0 to 5 postoperative day. These results were compared with those obtained from the control groups (42 patients). The ascitic level of IL-6 increased immediately after operation, then gradually decreased. The elevations of IL-6 from 0 to 5 postoperative day were remarkably higher in the OK-432 treated group, and those on 0 and 1 postoperative days were remarkably lower in CDDP treated group than in the control group. Similarly, the ascitic level of IL-8 elevated soon after operation and then decreased gradually. In the OK-432 treated group, the ascitic level of IL-8 was significantly higher than in the control group from 0 to 2 postoperative day. Ascitic TNF-alpha was detectable only in the ascites soon after operation in the OK-432 treated group. The ascitic level of sTNF RI peaked on 2 postoperative day in the control and the OK-432 treated group and 1 postoperative day in the CDDP treated group. There were no significant differences between these groups.
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PMID:[Changes of cytokine levels in ascitic fluid after intraperitoneal administration of OK-432 or CDDP]. 794 71

In order to evaluate the biological response after intraperitoneal administration of OK-432, we studied the changes of cytokine levels in ascitic fluid. In 6 advanced gastric cancer patients with peritoneal dissemination or extensive lymph node metastases, OK-432 20 KE was administered intraperitoneally during operation and the IL-6, IL-8 and IFN-gamma levels in ascitic fluid were measured from 0 to 5 postoperative days. These results were compared with those obtained from non-OK-432 administered control groups (17 cases). The ascitic level of IL-8 increased immediately after operation and gradually decreased. In the OK-432 treated group, the elevation of IL-8 on 0 and 1 postoperative days was remarkable, and there were statistically significant differences with the control group. Similarly, the ascitic level of IL-6 elevated soon after operation and then decreased gradually. In the OK-432 treated group, the ascitic level of IL-6 was significantly higher than in the control group after 3 postoperative days. There were no differences in changes of ascitic IFN-gamma levels between the groups. From these results, IL-6 and IL-8 appeared to be induced in ascitic fluid by intraperitoneal administration of OK-432.
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PMID:[Changes in cytokine levels in ascitic fluid after intraperitoneal administration of OK-432]. 837 2

Helicobacter pylori is the major causative agent of chronic gastritis. It is associated with duodenal and gastric ulcer and with the majority of primary gastric B-cell lymphomas; furthermore, there is a strong epidemiological association with gastric cancer. One intriguing aspect of this infection is the ability of H pylori to persist despite the vast array of host immune responses. This article reviews what is known about the immune responses against H pylori, emphasizing what is generally accepted and applicable while highlighting areas of controversy. The first section delineates the genesis of the inflammatory responses, which initiate with the production of tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, interleukin (IL)-1, IL-6, and IL-8 and continue with the recruitment of neutrophilic polymorphonuclear cells, lymphocytes, plasma cells, macrophages and eosinophils, and later with the development and recruitment of specifically committed cells (lymphocytes sensitized to H pylori antigens and B cells producing immunoglobulin (Ig)A, IgG, and possibly IgE antibodies against a variety of H pylori surface and flagellar proteins as well as bacterial toxins). The second part of the article focuses on the development of lymphoid follicles in the gastric mucosa, a phenomenon that for the first time links an immune response (the recruitment of mucosa-associated lymphoid tissue [MALT] to the gastric mucosa in response to H pylori infection) with the development of a neoplastic growth (the development of gastric MALT lymphomas). The local and systemic antibody responses are discussed in the light of their potential application in the development of diagnostic tests and vaccines. Particular emphasis is placed on the controversies surrounding the significance of antibodies directed against a 120 to 140 kDa protein apparently associated with more "aggressive" (sometimes also called "ulcerogenic" or "pathogenic") strains of H pylori.
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PMID:The immunobiology of Helicobacter pylori gastritis. 900 Apr 97

To estimate canine interleukin-8 (cIL-8) levels in blood plasma samples, a sandwich enzyme linked immunosorbent assay (ELISA) was established. For the development of the sandwich ELISA, polyclonal anti-cIL-8 (capturing), biotinylated anti-cIL-8 (developing) antibodies and glutathione-S-transferase/cIL-8 (GST/cIL-8) fusion protein as an antigen were used. cIL-8 in the fusion protein of GST/cIL-8 was detected in a dose dependent manner. The lowest limit of GST/cIL-8 detectable by this method was 2 ng/ml of GST/cIL-8 (containing; 0.470 ng/ml of cIL-8). IL-8 levels in the plasma samples from apparently healthy dogs were less than 0.470 ng/ ml. Higher levels of IL-8 were detected in the plasma samples of dogs with cystitis, dermatitis, and gastric cancer. These results suggest that the determination of cIL-8 by the sandwich ELISA is useful in diagnosis of inflammatory diseases in dogs.
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PMID:Establishment of a sandwich enzyme linked immunosorbent assay for canine interleukin-8. 903 76

Interleukin (IL)-8, a potent chemoattractant and activator of neutrophils, has been implicated to have a major role in the pathogenesis of gastric mucosal injury by Helicobacter pylori infection. We examined the relationship between cytotoxicity and IL-8 secretion induced by H. pylori. Furthermore, whether the vacuolating cytotoxin of H. pylori mediates IL-8 secretion from gastric epithelial cell lines was examined. Among the inflammatory cytokines, messages for IL-6, IL-8 and transforming growth factor-beta 1 were produced by gastric cancer (MKN45) cells in response to exposure to the cytotoxic strain of H. pylori. MKN45 incubated with the viable cytotoxic strain of H. pylori secreted IL-8. In contrast, the supernatant of neither the cytotoxic nor the non-cytotoxic strain induced IL-8 secretion. There was no correlation between IL-8 secretion and the intensity of cytotoxicity. In conclusion, these findings suggest that IL-8 secretion from MKN45 induced by H. pylori is mediated by factors other than cytotoxicity.
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PMID:Analysis of interleukin-8 secretion induced by Helicobacter pylori from the gastric epithelial cell line MKN45: a mechanism independent of the intensity of cytotoxicity. 919 82

Adherence of Helicobacter pylori to cultured gastric epithelial cells is associated with several cellular events, including the tyrosine phosphorylation of a 145-kDa host protein; the reorganization of the host cell actin and associated cellular proteins, like vasodilator-stimulated phosphoprotein, adjacent to the attached bacterial cell; and the subsequent release of the cytokine, interleukin 8 (IL-8). H. pylori isolated from patients with ulcer disease and gastric cancer contain a DNA insertion, the cag pathogenicity island (PAI), that is not present in bacteria isolated from individuals with asymptomatic infection. Mutations in a number of PAI genes abolish tyrosine phosphorylation and IL-8 synthesis but not the cytoskeletal rearrangements. Kinase inhibition studies suggest there are two distinct pathways operative in stimulating IL-8 release from host cells and one of these H. pylori pathways is independent of the tyrosine phosphorylation step.
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PMID:Induction of host signal transduction pathways by Helicobacter pylori. 920 37

Most strains of Helicobacter pylori from patients with peptic ulcer disease or intestinal-type gastric cancer carry cagA, a gene that encodes an immunodominant protein of unknown function, whereas many of the strains from asymptomatically infected persons lack this gene. Recent studies showed that the cagA gene lies near the right end of a approximately 37kb DNA segment (a pathogenicity island, or PAI) that is unique to cagA+ strains and that the cag PAI was split in half by a transposable element insertion in the reference strain NCTC11638. In complementary experiments reported here, we also found the same cag PAI, and sequenced a 39 kb cosmid clone containing the left 'cagII' half of this PAI. Encoded in cagII were four proteins each with homology to four components of multiprotein complexes of Bordetella pertussis ('Ptl'), Agrobacterium tumefaciens ('Vir'), and conjugative plasmids ('Tra') that help deliver pertussis toxin and T (tumour inducing) and plasmid DNA, respectively, to target eukaryotic or prokaryotic cells, and also homologues of eukaryotic proteins that are involved in cytoskeletal structure. To the left of cagII in this cosmid were genes for homologues of HsIU (heat-shock protein) and Era (essential GTPase); to the right of cagII were homologues of genes for a type I restriction endonuclease and ion transport functions. Deletion of the cag PAI had no effect on synthesis of the vacuolating cytotoxin, but this deletion and several cag insertion mutations blocked induction of synthesis of proinflammatory cytokine IL-8 in gastric epithelial cells. Comparisons among H. pylori strains indicated that cag PAI gene content and arrangement are rather well conserved. We also identified two genome rearrangements with end-points in the cag PAI. One, in reference strain NCTC11638, involved IS605, a recently described transposable element (as also found by others). Another rearrangement, in 3 of 10 strains tested (including type strain NCTC11637), separated the normally adjacent cagA and picA genes and did not involve IS605. Our results are discussed in terms of how cag-encoded proteins might help trigger the damaging inflammatory responses in the gastric epithelium and possible contributions of DNA rearrangements to genome evolution.
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PMID:Analyses of the cag pathogenicity island of Helicobacter pylori. 959 95

In Helicobacter pylori, a pathogenicity island (PAI) of approximately 40 kb, named cag, is present in a subset of strains. The strains containing the PAI are more virulent than those that do not contain it, and are associated with peptic ulcer and gastric cancer. A putative secretory mechanism is encoded by this PAI. This secretory system is thought to be involved in the induction of the proiflammatory lymphokine IL-8 and tyrosine phosphorylation of proteins in the gastric cells. We are currently investigating the potential toxic factors exported by this region.
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PMID:Pathogenicity island mediates Helicobacter pylori interaction with the host. 971 54

Interleukin-8 (IL-8) may play an important role in Helicobacter pylori infection-associated chronic active gastritis and peptic ulcer disease in human. We have recently reported that a gastric cancer cell line, MKN45, produced a massive amount of IL-8 upon coculture with live H. pylori. Moreover, H. pylori induced the activation of NF-kappaB as well as AP-1, leading to IL-8 gene transcription. In this study, we evaluated the effect of rebamipide, an antigastritis and antiulcer agent, on H. pylori-induced IL-8 production. Rebamipide inhibited the production of IL-8 in several gastric cancer cell lines infected with H. pylori. In addition, rebamipide suppressed H. pylori-induced IL-8 gene expression at the transcriptional level as revealed by northern blotting analysis and luciferase activity in cells that were transfected with a luciferase expression vector linked with a 5'-flanking region of the IL-8 gene (bp -133 to +44). Furthermore, rebamipide significantly suppressed the NF-kappaB activation by H. pylori infection. These results suggest that rebamipide may protect against the mucosal inflammation associated with H. pylori infection through inhibition of a proinflammatory cytokine, IL-8.
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PMID:Molecular analysis of suppression of interleukin-8 production by rebamipide in Helicobacter pylori-stimulated gastric cancer cell lines. 975 46


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