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

A serum B12-binding protein with increased sialic acid content (termed hepatoma B12-binding protein) that causes elevations of serum B12 and unsaturated B12-binding capacity has been found in some patients with hepatocellular carcinoma (hepatoma). We now report another patient with hepatoma with initial near-normal, unsaturated B12-binding capacity that increased 400-fold as the disease progressed and then fell 50% with response to chemotherapy. A perfusate of the tumor in the liver had 5 times more B12-binding protein than did the serum and was immunologically the same as the serum hepatoma B12-binding protein isolated from previous cases. A cell line derived from hepatoma produced significant amounts of B12-binding protein similar to hepatoma B12-binding protein, whereas cell lines from normal liver and other neoplasia did not. The hepatoma sera, perfusate, and media from the hepatoma cell line contained elevated sialyltransferase activity. These data suggest that some hepatomas produce increased hypersialylated B12-binding protein that is cleared slowly from the plasma and accumulates there as hepatoma B12-binding protein.
Cancer Res 1977 Jun
PMID:The clinical and physiological implications of hepatoma B12-binding proteins. 6 88

When compared to uninvolved adjacent tissue, metastatic tumors in human liver appear to have significantly reduced sialytransferase activity. No significant kinetic differences (Michaelis constants, thermostability, and pH optima) between noncancerous and cancerous tissue sialytransferase were found. Mixing experiments between cancerous and noncancerous tissues indicated that inhibitors of sialytransferase activity were present in cancerous tissue. Subsequent experiments demonstrated increased levels of bound sialic acid in the tumor tissues. Inasmuch as futuin, a sialoglycoprotein, inhibits sialyltransferase activity, the increased levels of bound sialic acid in tumor tissue may be responsible for the reduced enzyme activity in these tissues.
J Natl Cancer Inst 1978 Dec
PMID:Characterization of sialytransferase in noncancerous and neoplastic human liver tissue. 8 33

The following three parameters were studied in Morris hepatomas of different growth rates: (a) the specific activity of guanosine dephosphate (GDP)-fucose:glycoprotein fucosyltransferase and cytidine monophosphate (CMP)-N-acetylneuraminic acid:glycoprotein sialyltransferase, (B) the content of GDP-fucosee and CMP-N-acetylneuraminic acid, and (c) the activity of alpha-L-fucosidase and neuraminidase. Fucosyltrasferase activities were significantly elevated in all hepatomas investigated. Especially high levels of enzyme were measured in the rapidly growing tumors 7777, 66, and 3924A. The increase varied between 2- and 3-fold when compared with the corresponding host liver. Conversely, the activity of the sialytransferase was greatly decreased in all hepatoma lines with a rapid or intermediate growth rate. In the fast-growing tumor 9618A2, the activity was reduced to 8%. GDP-fucose and CMP-N-acetylneuraminic acid were determined by the isotope dilution technique. In normal rat liver from Buffalo or ACl rats, the concentration of GDP-fucose was 6.5+/-0.9 and 9.5+/-1.1nmoles/g, wet weight, respectively. In the fast-growing hepatomas 3924A and 9121, levels up to 21.5 nmoles/g, wet weight, were found, However, the content of CMP-N-acetylneuraminic acid in hepatomas was indluenced to a lesser extent by the degree of differentiation of the tumor. In the most rapidly growing tumor, 9618A2, a level of alpha-L- fucosidase seven times higher than in host liver was determined. Moreover, there existed a correlation bewteen the age of the hepatoma and enzyme activity. Within the 2nd week after inoculation, fucosidase activity increased from 130 to 343 nmoles/hr/mg of protein. Neuraminidase was measured in a new linked assay system. The activity of this enzyme was lowered by 50% or was at least unchanged when compared to the activity in host liver. Our results indicate that specific alterations of fucose metabolism are a characteristic feature of Morris hepatomas.
Cancer Res 1977 May
PMID:Glycosyltransferases and glycosidases in Morris hepatomas. 19 53

A simple assay for the determination of sialyltransferase activity is described. The method involves the isolation of the radioactive reaction product on cellulose paper discs washed with trichloroacetic acid, thereby greatly facilitating the handling of large numbers of assays. This procedure is both more accurate and more sensitive than that involving precipitation with protein denaturants and separation by centrifugation, and is applicable to both soluble and particulate enzyme preparations. The application of the method to the determination of sialytransferase in human plasma is detailed. Enzyme activity is elevated two-fold in both cancer patients and patients with non-malignant disease. This suggests that the diagnostic use of determinations of sialyltransferase activity may be limited by its non-specificity.
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PMID:The application of a simple, sensitive disc assay for sialyltransferase activity to particulate and soluble enzyme preparations and its use in measuring enzymatic activity in human plasma samples. 48 83

We have measured sialyltransferase, galactosyltransferase, and fucosyltransferase as sell as 5'-nucleotidase in the serum of breast cancer patients. Serum sialyltransferase values in 65 normal healthy females ranged from 2.6 to 8.5 units, with a mean of 5.4. In 25 women with operable primary breast cancer, serum sialyltransferase levels were found to be between 6.2 and 15.4 units. Marked elevation of this enzyme level (range, 8.8 to 36 units) was observed in 48 patients with metastatic breast cancer. Galactosyltransferase and fucosyltransferase measurements, however, showed considerable overlap between the controls and the cancer patients. On the other hand serum 5'-nucleotidase and sialyltransferase in breast cancer patients showed very similar patterns. Thus, serum 5'-nucleotidase values in 44 normal females ranged from 11.4 to 23.2 units, whereas the levels found in 30 patients with metastasis were between 25 and 71.8 units. The tissue origin of abnormal levels of serum glycosyltransferases and 5'-nucleotidase was discussed in relation to their physiological significance as well as their role as markers for diagnosing early malignant breast neoplasm and for monitoring the extent of metastasis.
Cancer Res 1978 Mar
PMID:Alterations in serum glycosyltransferases and 5'-nucleotidase in breast cancer patients. 62 76

Elevated levels of three plasma glycosyltransferases were associated with neoplasia in cancer patients, notably those with tumor metastatic to liver. We examined levels of sialyltransferase, galactosyltransferase, and fucosyltransferase in metastatic tumor and apparently uninvolved host liver tissue in attempts to delineate possible sources of elevated plasma enzyme levels. Highest levels of fucosyltransferase activity were found associated with tumor tissue; in contrast, sialyltransferase and galactosyltransferase activity was often highest at the tumor-liver interface.
J Natl Cancer Inst 1977 Jul
PMID:Glycosyltransferase levels in tumors metastatic to liver and in uninvolved liver tissue. 87 59

Levels of glycoprotein:sialyltransferase activity (EC 2.4.99.1; CMP-acetyl-neuraminate:D-galactosyl-glycoprotein N-acetylneuraminyl-transferase) were measured in plasma of patients with neoplastic disease, and were found elevated above normal control values in 85% of patients examined. There was a correlation between enzyme levels and course of disea-e in 46 of 57 patients studied serially during therapy. Plasma sialyltransferase may be a useful marker enzyme for monitoring effectiveness of therapeutic programs for disseminated neoplasms.
Cancer 1977 Mar
PMID:Alterations in plasma sialyltransferase levels in patients with neoplastic disease. 91 50

Levels of plasma sialyltransferase were measured in a patient with disseminated carcinoma of the testes. Initial enzyme values, elevated six fold above those in normal controls, were among the highest thus far encountered in a population of patients with various stages and types of malignancy. During a remarkable respose to chemotherapy with cis-diaminodichloroplatinum, plasma sialyltransferase levels fell markedly. Serial measurement of this enzyme may aid in evaluation of tumor responsiveness to therapy in patients whose disease is not readily measurable.
Cancer 1976 Nov
PMID:Alterations in plasma sialyltransferase associated with successful chemotherapy of a disseminated tumor. Case report. 99 Nov 25

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.
J Natl Cancer Inst 1975 Jan
PMID:Alterations in glycosyltransferase activity in human colon cancer. 111 12

Carbohydrate compositions of the membrane and cytoplasmic fractions of human normal and cancerous colonic mucosa were compared in patients with blood groups O and B. The total sugar content in both fractions was reduced in the cancer tissues to about one-third of that in the normal colonic mucosa. The sugars that are associated with mucinous glycoproteins such as fucose and N-acetylgalactosamine were reduced significantly, while sugars that are primarily associated with "serum-type" glycoproteins were relatively unchanged or reduced to a lesser extent. The activities of glycoprotein:glycosyltransferases were variable, some showing so significant change, others beinb significnatly reduced in cancerous tissues. A polypeptidyl:N-acetylgalactosaminyltransferase (an enzyme that catalyzes the transfer of the first sugar to hydroxyamino acids of the protein core of mucinous glycoproteins), a sialyltransferase (involved in the addition of sialic acid to mucinous glycoproteins), and a galactoxyltransferase (thought to be responsible for blood group B antigenicity) were reduced in the cancerous colonic tissue. In contrast, the activities of these glycosyltransferases were unchanged in the colonic mucosa of patients with granulomatosis or ulcerative colitis. Glycosidase activities in the normal, cancerous, and inflammatory tissues were the same. These results suggest that in colonic cancer tissues the synthesis of one type of oligosaccharide chain may be greatly affected, while another family of oligosaccharides may remain relatively unaffected.
Cancer Res 1975 Aug
PMID:Glycoprotein metabolism in inflammatory and neoplastic diseases of the human colon. 114 23


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