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)

The aim of this work was to investigate the extension of intestinal metaplasia (IM), as well as to quantitate various components of IM (namely sialomucins, sulfomucins and Paneth cells), in entire gastrectomy specimens from Swedish and Japanese patients. The length of the gastric mucosa was assessed by morphometry. The percent of sections with IM was regarded as the extension of IM in the specimens. Histochemically labeled sialomucins, sulfomucins and Paneth cells (the 3 main findings in gastric IM) were quantified in separate sections with the aid of an image analyzer. In total, 1,321 sections corresponding to 6 gastrectomy specimens were quantified. Sialomucins and sulfomucins were more extensively distributed in the 4 specimens with carcinoma than in the 2 without carcinoma (one having a peptic ulcer and the other, hereditary gastric cancer syndrome (HGCS) without carcinoma). On the other hand, quantitative analysis in Swedish specimens indicated that the highest values for sialomucins, sulfomucins and Paneth cells were present in HGCS. When Swedish and Japanese specimens with adenocarcinoma were compared, only sulfomucins (denoting Types II and III IM) were significantly higher in those carrying an intestinal-type carcinoma (ITC) than in those with diffuse-type carcinoma (DTC). The results substantiate those obtained with gastric biopsies by other authors. On the other hand, the mucosal extension and the amount of sulfomucins are not comparable parameters (since that mucin was not equally distributed, but "concentrated" in certain areas in the mucosa). One possible conclusion is that the focal distribution of acidic mucins and of Paneth cells in the gastric mucosa may strongly influence their detection rate in gastric biopsies. Thus, haphazard biopsy of the gastric mucosa may fail to sample areas with sulfomucins in population studies aiming to detect individuals at risk. Such sampling errors in gastric biopsies may explain the conflicting results on this subject appearing in the literature.
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PMID:Image quantitation of intestinal metaplasia in entire gastrectomy specimens from Swedish and Japanese patients. 869 20

Thirty cases of gastric cancer were studied. Slides were stained with PAS Alcian Blue. The staining characteristics of the mucin were correlated with gross characteristics of the tumours and histological types. Due to the few cases studied, there was no observed statistical significance between the various mucin staining characteristics with the histological type, sex site of tumour and ethnicity. In 84% of cases the tumour cells secreted either neutral or mixed mucins. Acid mucins were demonstrated in 5 cases only. Neutral mucin is normally secreted by gastric epithelium and neck cells of gastric glands. The observation in this study suggests that those tumours which secrete neutral and mixed mucin probably arise from gastric epithelium, neck cells of gastric glands or colonic metaplasia. In those cases where the tumour produces acid mucin it is possible the tumour arose from areas of intestinal metaplasia.
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PMID:Mucin secretion by gastric carcinoma cells: PAS alcian blue stain study. 875 22

Previous histochemical studies have shown that changes occur in the composition of mucins both in preneoplastic and neoplastic lesions of the gastric mucosa. Since monoclonal antibodies are now available which recognize the protein product of distinct mucin genes, they are likely to provide useful tools for evaluating these changes. Thus, a monoclonal antibody 996/1 raised against a peptide epitope of the colonic mucin MUC2 was examined for its potential as a prognostic indicator in gastric cancer. 996/1 works well on formalin-fixed paraffin sections and shows good staining of the colonic goblet cells in the region of the golgi, while there is no staining of normal control gastric mucosa. The epitope was detected in all cases of intestinal metaplasia (44 samples) and some but not all cases of dysplasia (26 samples) and gastric carcinoma (74 samples). There was no significant difference between the positivity of the tumours according to their classification, stage and lymph node status. These results unfortunately gave little indication that this antibody would be a useful prognostic tool in gastric cancer. However, the pattern of 996/1 staining provides useful information about the molecular changes in mucin expression that occur in gastric carcinogenesis.
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PMID:Expression of a peptide epitope of the colonic mucin MUC2 in precursor lesions to gastric carcinoma. 889 66

Expression of trefoil group antigen pS2 was examined immunohistochemically in resected stomachs from 121 patients with gastric cancer. Gastric cancer was classified as either undifferentiated or differentiated by histology, and was also divided into gastric type or non-gastric type by mucin-histochemistry. Immunoreactive pS2 was present in 20% of early cancers and 30% of advanced cancers (NS), and in 25% of undifferentiated and 15% of differentiated early cancers (NS), whereas the antigen was present in 38% of undifferentiated and 15% of differentiated advanced cancers (p = 0.04). Positivity for pS2 was found more often in gastric type early cancer (p = 0.04) as well as advanced cancer (p = 0.0002), and was also more frequent in cancers showing scirrhous (p = 0.04) and infiltrative growth (p = 0.03). Cancer positive for pS2 was characterized by mucin-histochemistry and microscopy as gastric type with scirrhous growth and diffuse infiltration, and thus the expression of pS2 in gastric cancer appears to be related to the growth of cancer with these characteristics.
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PMID:[Expression of trefoil group antigen pS2 in human gastric cancer]. 892 4

Two human diffuse gastric carcinoma cell lines were established in vitro from xenografted tumours serially passaged in nude mice. Of 12 primary diffuse gastric carcinomas, 7 were successfully xenografted in nude mice (58.3%). Short-term primary cultures were achieved in all the xenografted lines. However, only 2 of the 7 short-term primary cultures were established as long-term cultures (GP202 and GP220). GP202 cells are larger than GP220 cells, show less abundant intercellular junctions at the ultrastructural level and grow in culture as a compact thin monolayer. The GP220 cells grow preferentially in small clusters attached to the monolayer, with a subpopulation of floating cells. Both lines have cells containing small mucin vacuoles in the cytoplasm and cells displaying a typical signet-ring shape. GP202 cells grow as solid tumours in nude mice but GP220 cells do not give rise to tumours. The flow cytometry and karyotype analysis showed aneuploidy in GP202 cells, with many numerical and structural chromosomal abnormalities, and diploidy in GP220 cells, with several structural chromosomal abnormalities. The CDw75 and Tn antigens are more prominently expressed in GP202 cells than in GP220 cells. T antigen is only expressed in GP202 cells, whereas only GP220 cells express EGFR. Sialosyl-Tn is not expressed in either of the cell lines. The gastric cancer cell lines described in this paper represent a valuable addition to the small number of diffuse gastric cancer cell lines currently available and also provide a good model for further in vitro and in vivo studies of gastric carcinogenesis.
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PMID:Establishment and characterization of two cell lines derived from human diffuse gastric carcinomas xenografted in nude mice. 892 30

Gastritis is a histopathologic diagnosis, which correlates poorly with both clinical symptoms of non-ulcer dyspepsia and endoscopic abnormalities. Worldwide, most cases of gastritis are due to Helicobacter pylori and are characterized by a diffuse superficial antral gastritis. Chronic inflammatory cells and lymphoid follicles are present in the lamina propria. Neutrophils are present in the surface and pit-lining epithelium. In North America and Western Europe, reactive gastropathy due to duodenal reflux or non-steroidal anti-inflammatory agents is also common. In this condition, there is no increase in inflammatory cells, but the pit-lining cells become hyperplastic, and the pits have a corkscrew appearance. Most examples of multifocal atrophic gastritis are the result of long standing Helicobacter gastritis, although there may be other causes as well. It is characterized by loss of glands in both pyloric and corpus mucosae with intestinal metaplasia of the surface epithelium. A subtype of intestinal metaplasia, in which sulphomucin (large bowel mucin) is present, has been associated with the development of distal gastric cancer. However, this association is relatively weak and is not considered useful for screening purposes. Gastric dysplasia may develop in areas of the stomach affected by intestinal metaplasia. High-grade dysplasia is a significant finding, with up to 60 percent of cases having coincident carcinoma and a further 25 percent of cases likely to develop an invasive malignancy within fifteen months.
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PMID:The morphology of gastritis. 904 89

The aim of this study was to evaluate the usefulness of gastric and intestinal epithelial phenotypic expression of gastric cancer cells, shown by mucin histochemical staining (paradoxical concanavalin A, galactose oxidase Schiff [GOS] and sialidase-GOS) and immunohistochemical reactivity (pepsinogens, SH-9, and TKH-2), as an adjunct to the assessment of depth of invasion of gastric carcinomas by endosonography (ES). In 110 resected adenocarcinomas, the proportion of intestinal-type cells increased with progression, as assessed by depth of invasion. The coincidence rate for gastric and intestinal phenotypic expression in biopsied and resected specimens was 96.3%. The positive predictive value of assessment of depth of invasion by ES was 73%. A low positive predictive value (45%) was achieved with type II-3 cases (according to our classification). However, the predictive value improved to 68% when depth of invasion was evaluated as the submucosal layer or deeper in cases in which more than 10% of cancer cells were of intestinal-type, although statistical analysis showed no significant difference between these predictive values. The sensitivity of diagnosis of submucosal invasion by cell differentiation in the type II-3 cases was significantly higher than that for the other types (89.5% versus 59.1%; P = 0.037). Phenotypic expression in biopsied specimens of gastric carcinomas proved helpful for evaluating the depth of invasion of gastric carcinoma by ES.
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PMID:Histochemical and immunohistochemical study of human gastric carcinoma differentiation with special reference to supplementary role for endosonography in evaluating depth of invasion. 908 64

Helicobacter pylori was first isolated only in 1983, but has rapidly gained an extraordinary prominence in gastroenterology and medical microbiology. It lives only in the human stomach beneath the mucin layer which protects it from the lethal effects of gastric acid. Although it has a very high prevalence (30-40% in developed and more than 80% in developing countries), the route of infection is not known; gastro-oral and faecal routes have been postulated. The organism is associated with gastritis, duodenal and gastric ulcers and gastric cancer as well as a number of diseases at distant sites. It can be eradicated with combinations of antibiotics, after which the rate of infection is low.
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PMID:The microbiology of Helicobacter pylori. 920 83

UDP-N-acetylgalactosamine:polypeptide N-acetylgalactosaminyltransferases (GalNAc transferases) catalyze the initial reaction in O-linked (mucin type) oligosaccharide biosynthesis. To attempt to inhibit the synthesis of O-glycan, we transfected antisense cDNA of GalNAc transferase type 1 (GalNAc-T1) into a human gastric cancer cell line, JRST. A decreased expression of GalNAc-T1 at the level of both mRNA and protein was observed in the resultant transfectants. They demonstrated a significantly increased sensitivity to NK and lymphokine-activated killer cells in vitro compared with parental cells and mock transfectants. Although there was no significant difference in in vitro cell proliferation among parental cells, mock transfectants, or antisense transfectants, the in vivo growth rate of antisense transfectants using SCID mice was clearly lower than that of parental cells and mock transfectants. Furthermore, the treatment of mice with anti-asialo-G(M1) Ab abolished this growth-inhibitory effect of antisense transfection. From these results, we conclude that antisense suppression of GalNAc-T1 could increase the sensitivity of tumor cells to NK and lymphokine-activated killer cells, suggesting that this strategy may be of use as a new immunogene therapy.
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PMID:Increased sensitivity of gastric cancer cells to natural killer and lymphokine-activated killer cells by antisense suppression of N-acetylgalactosaminyltransferase. 930 Jun 83

Mucin molecules are displayed on most human cancer cell surface, and are different from that expressed on normal epithelial cells. The molecular structure of mucin core peptide (apomucin) was identified recently. However, the function of apomucin is only poorly understood. To further elucidate the role of apomucin in the modulation of cancers, this study was to investigate the immune responses induced by mucin core peptide in mice. The mucin core peptide was isolated from pancreatic cancer cell line SW1990. When mice immunized with this apomucin (10 micrograms/time x 6) plus DETOX, all mice developed delayed-type hypersensitivity (DTH) after challanged with apomucin or synthetic mucin core peptide MUC-2 or MUC-3, while the mice immunized with only apomucin did not develop DTH. No antibodies were detected by ELISA after immunization. When the splenic cells of vaccinated mice were cocultured with this apomucin (10-50 micrograms/ml) and rhIL-2 (50 U/ml) in vitro, the proliferated lymphocytes showed cytotoxicity against human cancer cells, including colon cancer, gastric cancer, pancreatic cancer and leukemia as measured by Cr-51 release assay. The cytotoxicity could be blocked by antibodies against MUC-2 and MUC-3. These results provide a rational basis for the use of apomucin as a vaccine to stimulate anti-tumor immunity.
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PMID:[Anti-tumor activity and immune responses induced by human cancer-associated mucin core peptide]. 938 91


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