Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.4.99.7 (sialyltransferase)
 1,534 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The recent reports of the use of serum and tissue enzyme assays in primary diagnosis and then in following the course of the disease have been reviewed. These include use of bone marrow acid phosphatase, isoenzymes of both acid and alkaline phosphatase, LDH5/LDH1 ratios, sialyltransferase and the combination of carcinoembryonic antigen with serum enzyme assays to help in prediction of the occurrence of hepatic metastases.
 ...
PMID:Enzyme patterns in cancer. 32 72

Glycosyltransferase enzymes were measured in homogenates of normal and neoplastic colon epithelium. The levels for exogenous galactosyltransferase and fucosyltransferase and endogenous N-acetylglucosaminyl-transferase were higher in the normal tissue. The levels for exogenous and endogenous sialyltransferase and endogenous galactosyltransferase and fucosyltransferase were comparable in the homogenates of normal and cancer cells. Incorporation of fucose and galactose into purified carcinoembryonic antigen (CEA), used as an exogenous acceptor by colon glycosyltransferases, was demonstrated by immunoprecipitation with rabbit antiserum to human CEA. The normal fucosyltransferase and galactosyltransferase showed higher activity with CEA than did the tumor enzymes.
 ...
PMID:Alterations in glycosyltransferase activity in human colon cancer. 111 12

Sialyltransferase activity (EC 2.4.99.6) was measured in the microsomal fraction of colorectal cancer cell lines using an assay based on the incorporation of [14C]CMP-sialic acid into asialofetuin. In the poorly differentiated lines MIP101 and Clone A, sialyltransferase activity had a Vmax of 0.36 and 0.31 nmol/mg protein/h, respectively, while the moderately differentiated to well-differentiated cell lines HT-29, CCL188, and CX-1 had Vmaxs of 2.46, 1.05, and 1.24 nmol/mg protein/h, respectively. All cell lines tested had a Km of 15.4 (+/- 0.7)(SD) mumol/liter. The better differentiated cells had higher levels of sialyltransferase activity, which correlated with their higher levels of sialic acid and their enhanced ability to form liver metastases in the nude mouse following intrasplenic injection compared to the poorly differentiated cell lines. Treatment of the cell lines with KI-8110, a CMP-sialic acid derivative which prevents incorporation of sialic acid into glycoconjugates, resulted in reduced formation of hepatic metastases by the colorectal carcinoma cell lines in the nude mouse model. It is suggested that reduced sialylation of adhesion molecules such as carcinoembryonic antigen may change the biology of the tumor cell, one consequence of which is the prevention of implantation of the cells into distant sites, resulting in a reduced incidence of metastases.
 ...
PMID:Sialyltransferase activity and hepatic tumor growth in a nude mouse model of colorectal cancer metastases. 131 99

Plasma carcinoembryonic antigen (CEA) and sialyltransferase levels were assayed in 21 cancer patients to correlate them in response to therapy. Plasma sialyltransferase and CEA level correlated well in 10 colon, 4 breast and 1 lung cancer patients in response to therapy. There was a negative correlation in one colon cancer, 3 breast cancer and 2 lung cancer patients. Plasma sialyltransferase was a better marker for breast and lung cancer. CEA was a good marker for colon cancer.
 ...
PMID:Correlation between plasma carcinoembryonic antigen (CEA) and sialyltransferase as tumor marker. 659 15

Serum-sialyltransferase activity was measured in serum samples of 116 patients with malignant tumors of various origins and different clinical stages using asialo-fetuin as the acceptor and cytidine-5'-mono-phospho[14C]sialic acid as the donor. Only patients with metastatic tumors had significantly elevated serum-sialyltransferase levels. Increased enzyme activity was also associated with rheumatoid arthritis and with acute hepatitis, whereas no significant alteration of enzyme activity was observed in cystic fibrosis patients. In a group of tumor patients, various additional tumor markers were determined (carcinoembryonic antigen, alkaline phosphatase: Regan isoenzyme, creatinekinase: BB-isoenzyme, lactatedehydrogenase: isoenzyme 5) and the data compared to the clinical diagnoses. The sensitivity and specificity of serum-sialyltransferase as a tumor marker is assessed.
 ...
PMID:Serum-sialyltransferase activity in cancer patients. 704 8

The present study gives an evaluation of carcinoembryonic antigen (CEA), macrophage electrophoretic mobility test (MEM), sialyltransferase, galactosyltransferase isoenzyme (SGT), ribonuclease and reverse transcriptase as diagnostic aids in malignant diseases. CEA and sialyltransferase are of certain value in the monitoring of cancer, as their values in the serum may rise before progression of disease or relapse. Both tests are not reliable parameters in the early diagnosis of malignancy. Our results with regard to the MEM test have not proved in any way useful in the diagnosis of cancer. Our preliminary results appear to indicate that, provided further simplification of the method can be achieved, SGT isoenzyme determination seems to be a better means of diagnosing cancer. In view of inherent-methodological difficulties reverse transcriptase has, at present, no clinical application in the diagnosis of cancer.
 ...
PMID:[Developments in the serological diagnosis of malignant diseases]. 746 58

To address the function of carbohydrates in mucins, GalNAcalpha-O-bn has been used in in vivo experiments on several human mucosal cultured cells as a potential competitor of the glycosylation of N-acetylgalactosamine residues. GalNAcalpha-O-bn is metabolized by glycosyltransferases expressed in the cell, and give rise to different internal derivatives starting in particular from the formation of the disaccharide Galalpha1-3GalNAcalpha-O-bn. In this line, GalNAcalpha-O-bn exposure inhibits peripheral glycosylation according a cell-type specific manner. The metabolic alterations are very important in HT-29 cell line, leading to a massive accumulation of GalNAcalpha-O-bn oligosaccharide derivatives and to a strong inhibition of the terminal elongation of O-glycans by alpha2,3 sialyltransferase ST3Gal I. GalNAcalpha-O-bn treatment also induced alterations at the cellular level, exhibiting a large scale in HT-29 cells, i.e. 1) an inhibition of mucin secretion, 2) a blockade in the targeting of some membrane glycoproteins (brush border glycoproteins such as dipeptidylpeptidase IV, carcinoembryonic antigen and the mucin-like glycoprotein MUC1, and the basolateral cell adhesion molecule CD44), 3) an inhibition in the processing of lysosomal enzymes. Morphological abnormalities have been evidenced in GalNAcalpha-O-bn treated cells, in particular the accumulation of numerous intracellular vesicles in HT-29 cells. Taken together, these data suggest that O-glycosylation might be involved in the regulation of the targeting of O-glycosylproteins through carrier vesicles.
 ...
PMID:Inhibition of the glycosylation and alteration in the intracellular trafficking of mucins and other glycoproteins by GalNAcalpha-O-bn in mucosal cell lines: an effect mediated through the intracellular synthesis of complex GalNAcalpha-O-bn oligosaccharides. 1157 61