Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0699790 (colon cancer)
 28,837 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human colon cancer is associated with antigenic and structural changes in mucin-type carbohydrate chains (O-glycans). To elucidate the control of the biosynthesis of these O-glycans is colon cancer, we have studied glycosyltransferase and sulphotransferase activities involved in the assembly of elongated O-glycan structures. We analysed homogenates prepared from cancer tissue, adjacent normal and distal normal tissue from 20 patients. Several transferase activities showed pronounced changes in cancer tissue. The changes correlate with previous findings of a loss of O-glycans in cancer mucins, but did not always correlate with levels of Tn, sialyl-Tn, T and Lex antigens in homogenates or with the differentiation status and Duke's stages of the cancer tissue or the patient's blood type, sex and age. UDP-GlcNAc: Gal NAc-R beta 3-N-acetylglucosaminyltransferase (where GlcNAc is N-acetyl-D-glucosamine and GalNAc is N-acetyl-D-galactosamine) synthesizing O-glycan core 3, GlcNAc beta 1-3GalNAc-, CMP-sialic acid: GalNAc-peptide alpha 6-sialyltransferase synthesizing the sialyl-Tn antigen and sulphotransferase activities towards O-glycan core 1, Gal beta 1-3GalNAc-, were found to be decreased in cancer. UDP-GlcNAc: Gal beta 1-3GalNAc beta 6-N-acetylglucosaminyltransferase was also decreased in cancer concomitant with a loss of the ability to synthesize the I antigen and core 4, GlcNAc beta 1-6(GlcNAc beta 1-3) GalNAc-, CMP-sialic acid: Gal beta 1-3GalNAc-R alpha 3-sialyltransferase and GDP-fucose: Gal beta-R alpha 2-fucosyltransferase, synthesizing the blood group H determinant, were found to be 4- and 3- to 8-fold increased, respectively, in cancer compared to normal tissue. The data suggest that the biosynthesis of antigens and mucin-bound O-glycan structures in colon cancer is subject to complex control mechanisms.
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PMID:Alterations of O-glycan biosynthesis in human colon cancer tissues. 773 50

The expression of the mucin-bound sialyl-Lewisx epitope is increased in the tissue of most colorectal carcinomas and in the sera of about 30% of tumor patients. In colon cancer, a portion of the sialyl-Lex groups detectable with the monoclonal antibody AM-3 is located on MUC1 (C. Hanski et al., Cancer Res., 53: 4082-4088, 1993). In order to characterize the major colon carcinoma-associated sialyl-Lex-positive glycoprotein components, the tissue- and serum-derived antigens were investigated. The buoyant densities of the sialyl-Lewisx-positive antigens from tumor and normal colonic tissues and from sera of patients with colon carcinoma and healthy donors correspond to that of mucins (1.40 g/ml). The sialyl-Lex-positive mucins purified from both tissues elute under nonreducing conditions in the void volume of a Sepharose CL-2B column, indicating a molecular mass more than 2 x 10(7) daltons. They yield in immunoblot after SDS gel electrophoresis under reducing conditions a main band at an apparent M(r) 880,000. Radioactive labeling revealed that the band at M(r) 880,000 is the major protein component in sialyl-Lewisx-positive mucins both from tumor and normal colonic tissue. In sera of colon carcinoma patients, the sialyl-Lex moiety is also detectable mainly on a M(r) 880,000 glycoprotein band and, additionally, on a M(r) 140,000 molecule as well as on alpha 1-acid glycoprotein. Sera from healthy donors exhibited only a sialyl-Lex-positive glycoprotein with the apparent M(r) 140,000. Sandwich ELISA as well as immunoblots of mucins purified from the colon carcinoma cell line LS174T indicated that the sialyl-Lex moiety migrating in the M(r) 880,000 band is located on MUC2 protein core. Together, these data suggest that sialyl-Lex antigen in colon, colon carcinoma, and the sera of patients with this tumor is located on the MUC2 molecule, consisting of several subunits with an apparent M(r) 880,000, linked via disulfide bridges. The increase of sialyl-Lex expression in colon carcinomas appears to be mainly due to a more frequent transfer of sialyl-Lex moieties onto the mucin core in tumor tissue.
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PMID:Characterization of the major sialyl-Lex-positive mucins present in colon, colon carcinoma, and sera of patients with colorectal cancer. 785 Aug 10

The trefoil peptides, a recently recognized family of protease-resistant peptides, expressed in a regional specific pattern throughout the normal gastrointestinal tract. Although these peptides have been hypothesized to act as growth factors, their functional properties are largely unknown. Addition of recombinant trefoil peptides human spasmolytic polypeptide (HSP), rat and human intestinal trefoil factor (RITF and HITF) to subconfluent nontransformed rat intestinal epithelial cell lines (IEC-6 and IEC-17), human colon cancer-derived cell lines (HT-29 and CaCO2) or nontransformed fibroblasts (NRK and BHK) had no significant effect on proliferation. However addition of the trefoil peptides to wounded monolayers of confluent IEC-6 cells in an in vitro model of epithelial restitution resulted in a 3-6-fold increase in the rate of epithelial migration into the wound. Stimulation of restitution by the trefoil peptide HSP was enhanced in a cooperative fashion by the addition of mucin glycoproteins purified from the colon or small intestine of either rat or man, achieving up to a 15-fold enhancement in restitution. No synergistic effect was observed by the addition of nonmucin glycoproteins. In contrast to cytokine stimulation of intestinal epithelial cell restitution which is mediated through enhanced TGF beta bioactivity, trefoil peptide, and trefoil peptide-mucin glycoprotein stimulation of restitution was not associated with alteration in concentrations of bioactive TGF-beta and was not affected by the presence of immunoneutralizing anti-TGF beta antiserum. Collectively, these findings suggest that the trefoil peptides which are secreted onto the lumenal surface of the gastrointestinal tract may act in conjunction with the mucin glycoprotein products of goblet cells to promote reestablishment of mucosal integrity after injury through mechanisms distinct from those which may act at the basolateral pole of the epithelium.
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PMID:Trefoil peptides promote epithelial migration through a transforming growth factor beta-independent pathway. 804 Feb 78

Monoclonal antibody CC83 is a second-generation high-affinity antibody directed against the TAG-72 antigen in colorectal cancer. Our objectives were to evaluate the biodistribution, pharmacokinetics and imaging properties of CC83 labelled with 99Tcm via a modified Schwartz technique. The immunological integrity of 99Tcm-CC83 was evaluated by size-exclusion FPLC and by determining the immunoreactive fraction in vitro against bovine submaxillary mucin. The biodistribution of 99Tcm-CC83 up to 24 h postinjection was evaluated in nude mice bearing subcutaneous LS174T human colon cancer xenografts. Blood radioactivity data was fitted to a one-compartment pharmacokinetic model. Images of tumour-bearing mice were obtained at 17-24 h postinjection with 99Tcm-CC83. 99Tcm-CC83 was eluted as intact immunoglobulin by FPLC analysis and the mean immunoreactive fraction was 0.49 +/- 0.15. Tumour uptake at 24 h postinjection was 11.2 +/- 4.1% i.d.g-1. Radioactivity in the blood was eliminated rapidly with a half-life of 8 h and tumour:blood ratios were > 2:1 at 24 h postinjection. LS174T tumours were successfully imaged in 3/3 mice. In vitro studies showed instability of 99Tcm-CC83 when challenged with cysteine and glutathione but not metallothionein, suggesting a metabolic route for the 99Tcm antibody in vivo. We conclude that CC83 labelled directly with 99Tcm retains its immunological integrity and capability specifically to target subcutaneous LS174T human colon cancer tumours hosted in nude mice. These results further suggest that 99Tcm-CC83 may have potential for imaging colorectal cancer in humans.
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PMID:Immunoscintigraphy of human colon cancer xenografts in nude mice using a second-generation TAG-72 monoclonal antibody labelled with 99Tcm. 804 23

Mucins, high-M(r) glycoproteins with a large amount of O-glycosidically linked carbohydrate, protect the colonic epithelial surface and are altered in ulcerative colitis and colon cancer. At least two mucin genes, MUC2 and MUC3, are expressed at high levels in the human intestine. As an experimental model for studying the biosynthesis of human intestinal mucins, we used HM3 colon cancer cells. When mature mucins labelled with [3H]glucosamine or [3H]threonine were analysed by gel filtration, it was found that secreted mucins (M(r) > 10(8) were larger than soluble cellular mucins (M(r) approx. 5 x 10(6)). Only secreted mucin was sensitive to reduction. Both MUC2 and MUC3 proteins, identified by labelling with [3H]threonine or [35S]cysteine and immunoprecipitation with antibodies to synthetic mucin peptides, were already of large size (M(r) > 180,000) by the earliest labelling time (5 min). The MUC3 precursor was completely degraded by trypsin, but the MUC2 precursor had a trypsin-resistant fragment of M(r) approx. 240,000 containing threonine and cysteine. The trypsin-resistant MUC2 fragment contained N-linked carbohydrate, as indicated by a decrease in size as a result of peptidyl N-glycosidase digestion or tunicamycin treatment of HM3 cells. These results show that HM3 colon cancer cells produce at least two distinct human intestinal mucins. They also indicate that the mechanisms of biosynthesis of intestinal mucins differ from those of other mucin-like glycoproteins that have been studied.
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PMID:Biosynthesis of two distinct types of mucin in HM3 human colon cancer cells. 811 Jan 87

KL-6, a circulating mucin-like glycoprotein, is a pulmonary adenocarcinoma-associated antigen and is also regarded as an indicator of disease activity of interstitial pneumonitis. KL-6 has extensive heterogeneous antigenic determinants and consists of multiple heterogeneous antigen molecules. We have searched for circulating KL-6-associated glycoproteins with superior diagnostic value to KL-6 as a tumor marker for pulmonary adenocarcinoma. A new murine monoclonal antibody EH-123 reacting with an asialosugar chain on KL-6 was established. A new KL-6-associated molecule detected by a bimonoclonal bideterminant sandwich assay using the EH-123 antibody as a catcher and horseradish peroxidase-labeled KL-6 as a tracer was designated as CAM 123-6. In 59% (22 of 37) of patients with pulmonary adenocarcinoma, serum levels of CAM 123-6 were abnormally elevated and the positive rate increased with the progression of clinical stage. Elevated levels were not detected in normal individuals or in patients with benign lung diseases, other histologic types of lung cancer, gastric cancer, colon cancer or breast cancer. CAM 123-6 was more specific to pulmonary adenocarcinoma than carcinoembryonic antigen (CEA), but the sensitivity of CAM 123-6 for pulmonary adenocarcinoma was similar to that of CEA. CAM 123-6 is a promising candidate as a serum tumor marker for pulmonary adenocarcinoma.
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PMID:A new serum tumor marker, CAM 123-6, highly specific to pulmonary adenocarcinoma. 814 2

Recent molecular biological approach has revealed the primary structure of some mucin core proteins. Most prominent characteristic is tandemly repeated sequences. cDNA cloning of 6 kinds of mucin core proteins, MUC1-6, have thus been performed. Among them, the entire structure was revealed on MUC1 and 2. MUC 1 is a type I transmembrane protein with a large number of tandem repeat consisting of 20 amino acids. We have found that mouse MoAb MUSE11 against adenocarcinoma, which detects circulating MUC1 in patients with gastrointestinal and pancreatic cancers, recognizes part of the tandem repeat of MUC1 using synthetic peptides. To date, some of the MoAbs to adenocarcinoma which were prepared for the last decade have been shown to react with the tandem repeat of MUC1(MUC1 epitope), suggesting that MUC1 epitope could be highly immunogenic in human. Recently, cytotoxic T-cells against MUC1 epitope were established from breast and pancreas cancer patients. We could also induce those T-cells from the patient with multiple myeloma. Interestingly, CTL functions in a HLA-unrestricted manner, and may be of use as an adoptive immunotherapy. In addition, we have found antibody against MUC1 epitope in patients with ulcerative colitis or colon cancer. EB virus-transformed B-cell clone producing antibody against MUC1 epitope has been established from a cancer patient. Thus, MUC1 is now considered as a targeting molecule for immunotherapy. Indeed, Longenecker's group in Canada has recently tried the basic evaluation for immunotherapy using synthetic peptides of MUC1.
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PMID:[Molecular biological analyses of mucin core proteins and their clinical application]. 831 84

A culture system is presented in which a biologically more relevant substrate in the form of a collagen membrane and a biologically more relevant diffusion gradient system for nutrient delivery to the cells are provided. Five established human colon cancer cell lines (Caco-2, DLD-1, Widr, HCT 116 and HCT 8) were cultured in this system and three of them showed increased differentiation compared with the same cells cultured on the usual cell culture substrates of plastic and glass and with cells grown in an anchorage-independent manner. Caco-2 cells grow on plastic as a monolayer of large pleomorphic cells with scant mucin production. When cultured in a gradient diffusion system in a sandwich of type I/IV collagen the Caco-2 cells showed the highest degree of morphological and biochemical differentiation as evidenced by cellular alignment, glandular formation and mucin production. Similarly DLD-1 cells exhibited the greatest degree of morphological and biochemical differentiation in a gradient system in a type I/IV collagen sandwich. HCT 116 and HCT 8 cells, however, showed little change in differentiation phenotype under any of the 11 culture conditions tested. Widr cells grew in a type I/IV collagen sandwich in a gradient diffusion system as multilayered sheets of cells with intercellular spaces, suggestive of a moderate increase in differentiation phenotype. As judged by morphology and mucin production a range of differentiation capacities is exhibited by the five cell lines tested under the optimal differentiating culture conditions, with the order from most able to differentiate to least able to differentiate being Caco-2 > or = DLD-1 > or = Widr > HCT 116 > or = HCT 8.
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PMID:A defined collagen substrate and nutrient diffusion gradient culture system allows human colon cancer cells to assume a more differentiated phenotype. 835 94

The original CA 125 serum tumor marker test is a homologous double-determinant (OC 125 monoclonal antibody based) assay for the quantification of tumor associated mucin-like CA 125 molecules present in the serum. Commercial kits, now supplied by various manufacturers (and in different versions, e.g. IRMA, EIA, etc.) are currently widely applied in the following clinical situations: (i) Monitoring of disease. Doubling or halving of CA 125 serum values correlated (in 87% of all cases) with tumor progression or regression, respectively. (ii) Early prediction of outcome. Deviation from the ideal CA 125 regression curve predicts poor outcome within 3 months of cytostatic treatment. (iii) Tumor status after completion of therapy. Patients with CA 125 > 35 U/ml have (in 95% of all cases) still tumor present (at second look surgery). However, patients with CA 125 < 35 U/ml have in 50% (mostly minimal) residual disease. (iv) Early detection of recurrence. After a complete remission, a rise in CA 125 precedes tumor recurrence in 75% of all patients, with lead times up to more then 1 year, surpassing the CT-scan in cheapness and accuracy. (v) Diagnosis and differential diagnosis. Only when used in combination with other markers, do CA 125 determinations have a value as a diagnostic adjunct in the discrimination of ovarian cancer patients from those with benign ovarian tumors and from those with advanced colon cancer. Today, optimal management of ovarian cancer patients can only be provided using the CA 125 serum test.
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PMID:CA 125 in gynecological pathology--a review. 836 5

The significance of mucinous carcinoma has been controversial since first described by Parham in 1923. Previous reports have suggested that mucinous tumors affect young patients, involve the more proximal colon, are more advanced at diagnosis, and have a poorer prognosis than nonmucinous colon carcinoma. More recent reports have refuted these results. In an effort to clarify the significance of mucinous histology, a retrospective review of cases of invasive colon cancer treated at the Ochsner Clinic between 1982 and 1985 was undertaken. Mucinous adenocarcinoma, as defined by > or = 50 percent mucin, was found in 52 patients. During the same period, 343 nonmucinous adenocarcinomas were resected. The mean age, distribution within the colon, stage at diagnosis, and survival of mucinous carcinoma patients were compared with those with nonmucinous tumors. Mucinous tumors presented at a statistically significant more advanced stage (38 percent vs. 22 percent Dukes C lesions; P < 0.01). No significant differences were seen in age at presentation, distribution within the colon, or stage-for-stage survival when the entire group was analyzed. Mucinous carcinomas of the rectum occurred at an advanced stage more frequently (P < 0.05) than nonmucinous rectal carcinomas and had a markedly worse five-year survival (11 percent vs. 57 percent; P < 0.002).
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PMID:Mucinous carcinoma--just another colon cancer? 838 Jan 40


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