UMLS:C0024623 - FACTA Search

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Query: UMLS:C0024623 (gastric cancer)
36,219 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Expression of sulfated carbohydrate chains in intestinal metaplasia (IM) and gastric cancer tissues was immunohistochemically evaluated by using a monoclonal antibody (MAb) 91.9H. While normal gastric tissues were negative for MAb 91.9H, IM and cancer tissues were positively stained with high frequency. The incidence was 67% for IM with chronic gastritis (n = 12), 95% for IM with gastric cancer (n = 21), 77% for well and moderately differentiated adenocarcinoma (n = 13), 48% for poorly differentiated adenocarcinoma (n = 23), 89% for signet-ring cell carcinoma (n = 9) and 100% for mucinous adenocarcinoma (n = 7). When poorly differentiated adenocarcinoma cases were divided into two groups, solid (n = 13) and non-solid types (n = 10), the incidences were 8% and 100%, respectively. These data suggest that MAb 91.9H could be of practical use as a new marker for IM and gastric cancer, and may be valuable for subgrouping poorly differentiated adenocarcinomas. Analyses of the core proteins for 91.9H epitope were then carried out. Comparison of immunostaining of ten poorly differentiated adenocarcinoma cases by MAb MUSE11 against MUC1 gene product with that by MAb 91.9H suggested that 91.9H epitope is not expressed on MUC1. Northern blot analysis of 10 pairs of gastric cancer and adjacent normal tissues with a MUC2 cDNA probe showed that the expression level of MUC2 mRNA was below the limit of detection. Thus, 91.9H epitope may be expressed on other proteins than MUC1 or MUC2 core proteins in gastric cancer.
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PMID:Expression of sulfated carbohydrate chains detected by monoclonal antibody 91.9H in human gastric cancer tissues. 751 85

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

De-glycosylation of mucins may expose new tumor-associated core protein epitopes. In this study, to attempt to develop useful markers for gastric cancers, we have purified and de-glycosylated gastric mucin and tried to establish monoclonal antibodies (MAbs). A MAb designated A3D4 among established MAbs was shown to react with gastric cancer with high frequency, but not with normal gastric epithelium. Among normal digestive organs, only the colon and gall bladder were positive for MAb A3D4. The incidence of positivity in gastric cancer was 75% for intestinal-type adenocarcinoma (n = 28), 40% for solid-type adenocarcinoma (n = 5) and 33% for signet/scirrhous-type adenocarcinoma (n = 15). Interestingly, adenoma and intestinal metaplasia (IM) with chronic gastritis or peptic ulcer were negative for MAb A3D4, whereas 8 out of 13 cases (62%) of IM with gastric cancer was positive. Western-blot analysis using the lysate from normal colon tissues revealed a high-molecular-weight (> 300-kDa) smear-like band. Immunohistochemical analysis indicated that the reactivity of MAb A3D4 was clearly increased when tissue sections were pre-treated with periodic acid or O-glycanase, while it was decreased by pre-treatment with trypsin or protease V8. There was no reactivity with the synthetic peptide encompassing the tandem-repeat sequence of MUC2 or MUC3. These data suggest that MAb A3D4 detects a novel gastric-cancer-associated mucin antigen whose epitope may be peptide in nature.
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PMID:A novel gastric-cancer-associated mucin antigen defined by a monoclonal antibody A3D4. 939 54

Our previous immunohistochemical studies for the expression of MUC1 mucin antigen (which was detected by monoclonal antibody DF3) and MUC2 mucin antigen (which was detected by polyclonal antibody anti-MRP) in pancreatic and intrahepatic bile duct tumors demonstrated that invasive carcinoma with poor outcome showed a pattern of MUC1+ and MUC2- expression, whereas many of the noninvasive tumors with favorable outcome showed a pattern of MUC1- and MUC2+ expression. To clarify the relationship between the expression of these mucin antigens and the biological properties of gastric cancers, the expression of MUC1 and MUC2 mucin antigens was examined immunohistochemically in 136 patients with gastric cancer invading the submucosa or the deeper layer, and the survival of the antigen-positive and antigen-negative patient groups was compared using the Kaplan-Meier method. For MUC1 mucin expression, different glycoforms of MUC1 were examined using four monoclonal antibodies (NCL-MUC-1-CORE, DF3, MY.1E12, and HMFG-1). The patients with MUC1+ mucin antigen staining in the carcinoma showed significantly worse survival than those with MUC1- mucin antigen staining. In contrast, the patients with MUC2+ mucin antigen staining in the carcinoma showed significantly better survival than those with MUC2- mucin antigen staining. In conclusion, MUC1 antigen expression was associated with a poor outcome in patients with gastric cancer, irrespective of its glycosylation status, and MUC1 is thus considered to be a useful prognostic factor for poor outcome in patients. In contrast, MUC2 antigen expression is a prognostic factor associated with a favorable outcome in patients. In addition, combined evaluation of the MUC1 and MUC2 mucin staining is clinically useful to predict outcome in patients with gastric cancer.
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PMID:Expression of MUC1 and MUC2 mucins in gastric carcinomas: its relationship with the prognosis of the patients. 982 23

At least seven human mucin genes have been described, which express glycoproteins MUC1-7 in various tissues. It has been shown that different mucins are expressed in various gastric disease states compared to the normal. In this study we used histochemical and immunohistochemical methods to determine the type and pattern of mucin in 54 patients with a variety of gastric conditions [i.e., normal controls, fetal stomachs, gastritis, low-grade dysplasia, intestinal metaplasia (associated with gastritis, benign ulcers, dysplasia, and cancer), early and advanced intestinal type adenocarcinoma, and diffuse adenocarcinoma]. We report for the first time the use of all seven MUC antibodies in the various conditions. Normal controls were immunoreactive for MUC4, 5, and 6 , and gastritis specimens showed similar results, although the latter showed more MUC1 immunoreactivity. Whereas early fetal stomach showed no MUC immunoreactivity, MUC4, 5, and 6 were present from the early second trimester onwards. There was no significant difference between dysplasia and intestinal metaplasia, both categories showing the presence of MUC2 and 3 predominantly. Early intestinal type adenocarcinomas did not show any mucins in the majority of cases. Advanced intestinal type adenocarcinomas showed immunoreactivity predominantly for MUC1, 5, and 6, as well as MUC2 in some cases. Diffuse adenocarcinomas showed strong positive MUC2 and 6 staining, and in some cases MUC5 and 7. In conclusion, we have shown different patterns of mucin immunoreactivity in various gastric disease states. Specimens with dysplasia, intestinal metaplasia, late intestinal type adenocarcinoma, and diffuse gastric cancer were characterized by increased diversity of mucin types, whereas early intestinal cancer showed loss of mucin immunoreactivity.
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PMID:Immunohistochemical detection of gastric mucin in normal and disease states. 1022 22

Human gastric mucous cells - gastric cancer cell lines mucin gene expression - TNFalpha - RT-PCR immunocytochemistry Little is known on the expression pattern of mucin genes in human gastric cancer cell lines in relation to mucin expression in normal gastric epithelial cells. Thus, the aim of this study was to compare gastric cancer cell lines and non-transformed epithelial cells in their expression of the different mucin genes, in order to use these cells as models for physiological MUC expression in human stomach. Human gastric mucous cell primary cultures which were obtained from surgical specimen by collagenase/pronase treatment and a panel of six human gastric cancer cells were screened for mRNA expression of the mucin genes MUC1, MUC2, MUC5AC, MUC5B, and MUC6. Mucin gene expression was analyzed by semi-quantitative RT-PCR, and by Western blotting and immunocytochemistry. Primary cultured human gastric mucous cells retained the stomach-specific pattern of mRNA expression found in gastric mucosal biopsies (MUC1, MUC5AC, MUC6), whereas any gastric cancer cell line exhibited an aberrant mucin gene expression. Mucin gene expression showed large variations in levels and patterns from cell line to cell line, but MUC2 was aberrantly expressed in all cancer cells. Immunocytochemistry confirmed aberrant MUC2 protein expression in cancer cells. The expression of the secretory mucin genes MUC2 and MUC5AC varied in relation to the length of cultivation of the cancer cell lines. Treatment of the gastric cancer cells with TNFalpha resulted in an enhanced mRNA expression of MUC1, MUC2, and MUC5AC (2-fold increase within 3 hours; p <0.05). In contrast, immunocytochemistry disclosed a decrease in MUC2 and MUC5AC staining intensity. Our results indicate that primary cultured human gastric mucous cells provide a physiological in vitro system for investigations of gastric mucin gene regulation. In gastric cancer cells marked changes in the mucin gene expression pattern are found with coexpression of non-gastric type mucins. Gastric mucin gene expression may be regulated by proinflammatory cytokines which could have implications in gastritis.
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PMID:Variation of human mucin gene expression in gastric cancer cell lines and gastric mucous cell primary cultures. 1060 60

In gastric cancer, altered expression of MUC1, MUC2, MUC5AC, and MUC6 mucin genes has already been described. We show in this report by the means of in situ hybridization, reverse transcriptase-polymerase chain reaction, and transfection assays that MUC5B is also abnormally expressed in gastric carcinomatous tissues and cell lines. We thus undertook to elucidate the molecular mechanisms that regulate the transcription of MUC5B in gastric cancer cells. To this end, high expressing (KATO-III) and low expressing (AGS) gastric cancer cell lines were chosen to study human mucin gene MUC5B expression and promoter activity. Sequencing of the promoter region revealed a distal TATA box located 1 kilobase upstream of the proximal TATA box. Functional activity of the promoter was addressed by using deletion mutants covering 2044 nucleotides upstream of the MUC5B transcription start site. We identified a distal promoter 10 times more active than the proximal promoter in KATO-III cells. In AGS cells, both promoters, much less active, showed the same range of activity. Binding assays allowed us to show that the transcription factor ATF-1 binds to a cis-element present in the distal promoter. Sp1, which binds to both promoters specifically transactivates the proximal promoter. Treatment of transfected cells with PMA, cholera toxin A subunit, and calcium ionophore showed that only PMA led to a substantial activation of the distal promoter. MUC5B 5'-flanking region having a high GC content, influence of methylation on the MUC5B expression was assessed. Our results indicate that repression of MUC5B expression visualized in AGS cells is due in part to the presence of numerous methylated cytosine residues throughout the 5'-flanking region. Altogether these results demonstrate that MUC5B expression in gastric cancer cells is governed by a highly active distal promoter that is up-regulated by protein kinase C and that repression is under the influence of methylation.
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PMID:Aberrant expression of human mucin gene MUC5B in gastric carcinoma and cancer cells. Identification and regulation of a distal promoter. 1127 96

We investigated the biologic behavior of gastric phenotype carcinoma of the stomach, especially in association with degradation of the extracellular matrix. One hundred fourteen lesions of intramucosal gastric carcinoma (IMGC) of differentiated type were studied. IMGCs were classified into 4 phenotypic categories--complete intestinal type (C type), incomplete intestinal type (I type), gastric type (G type), and unclassified type--through a combination of the expression of CD10, MUC2, HGM, and Con A. The expression of MMP-2, MMP-9, TIMP-2, and type IV collagen was investigated by immunohistochemical staining. The incidence of C-type IMGC, I-type IMGC, and G-type IMGC was 7.9%, 55.3%, and 36.8%, respectively. The incidence of positive MMP-9 expression in G-type IMGCs (57%) was significantly higher than that in C-type IMGCs (11%) or I-type IMGCs (35%) (P < .01). There was no significant correlation between phenotypes and expression of MMP-2, TIMP-2, or type IV collagen. There was a reverse correlation between the expression of type IV collagen and the expression of type IV collagenase (P < .001). In conclusion, gastric phenotype carcinomas have been shown to be highly invasive and metastatic, However, although they can potentially degrade the extracellular matrix via overexpression of MMPs compared with intestinal phenotype carcinoma, our data show no statistically significant separation of subtypes of intramucosal gastric cancer based on gross classification, histologic type, lymphatic or venous invasion, or lymph node metastases.
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PMID:Relationship between biologic behavior and phenotypic expression in intramucosal gastric carcinomas. 1182 76

Intestinal metaplasia (IM) is part of a stepwise sequence of alterations of the gastric mucosa, leading ultimately to gastric cancer, and is strongly associated with chronic Helicobacter pylori infection. The molecular mechanisms underlying the onset of IM remain elusive. The aim of this study was to assess the putative involvement of two intestine-specific transcription factors, CDX1 and CDX2, in the pathogenesis of gastric IM and gastric carcinoma. Eighteen foci of IM and 46 cases of gastric carcinoma were evaluated by immunohistochemistry for CDX1 and CDX2 expression. CDX1 was expressed in all foci of IM and in 41% of gastric carcinomas; CDX2 was expressed in 17/18 foci of IM and in 54% of gastric carcinomas. In gastric carcinomas, a strong association was observed between the expression of CDX1 and CDX2, as well as between the intestinal mucin MUC2 and CDX1 and CDX2. No association was observed between the expression of CDX1 and CDX2 and the histological type of gastric carcinoma. In conclusion, these results show that aberrant expression of CDX1 and CDX2 is consistently observed in IM and in a subset of gastric carcinomas. The association of CDX1 and CDX2 with expression of the intestinal mucin MUC2, both in IM and in gastric carcinoma, indirectly implies that CDX1 and CDX2 may be involved in intestinal differentiation along the gastric carcinogenesis pathway.
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PMID:Expression of intestine-specific transcription factors, CDX1 and CDX2, in intestinal metaplasia and gastric carcinomas. 1247 24

Gastric intestinal metaplasia (IM) and gastric cancer are associated with Helicobacter pylori, but the bacterium often is undetectable in these lesions. To unravel this apparent paradox, IM, H. pylori presence, and the expression of H. pylori virulence genes were quantified concurrently using histologic testing, in situ hybridization, and immunohistochemistry. H. pylori was detected inside metaplastic, dysplastic, and neoplastic epithelial cells, and cagA and babA2 expression was colocalized. Importantly, expression of cagA was significantly higher in patients with IM and adenocarcinoma than in control subjects. The preneoplastic "acidic" MUC2 mucin was detected only in the presence of H. pylori, and MUC2 expression was higher in patients with IM, dysplasia, and cancer. These novel findings are compatible with the hypothesis that all stages of gastric carcinogenesis are fostered by persistent intracellular expression of H. pylori virulence genes, especially cagA inside MUC2-producing precancerous gastric cells and pleomorphic cancer cells.
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PMID:Intracellular and interstitial expression of Helicobacter pylori virulence genes in gastric precancerous intestinal metaplasia and adenocarcinoma. 1269 95

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