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)

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.
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PMID:Alterations in serum glycosyltransferases and 5'-nucleotidase in breast cancer patients. 62 76

In forty-one carcinomas and sixteen benign lesions (fibroadenoma and mastopathy) of the human breast, immunohistochemical expression of sialylated and non-sialylated forms of both Lea and Lex, and the A, B, and H type 2 blood group substances were studied by using an indirect immunoperoxidase staining. In normal ductal epithelium and benign lesion of breast, Lewis-related antigens were mostly expressed. Breast carcinomas showed these antigens with the following frequencies: Lea, 31.7% (13/41); sialyl Lea, 56.1% (23/41); Lex, 46.3% (19/41); sialyl Lex, 68.3% (28/41); A/B/H type 2, 38.1% (16/41). Sialylated forms of Lea and Lex were observed more frequently than their respective non-sialylated forms in breast carcinomas. In both one normal epithelium and four carcinomas of breast with Le(a-b-) phenotype, the expressions of type 2 antigens were observed, while type 1 antigens were not consistently expressed. Although compatible expression was observed in all specimens of both normal epithelium and benign lesion of breast, twenty-four cases with the deletion of A and/or B antigens, six cases with H type 2 accumulation and one case with incompatible expression were demonstrated in breast carcinoma. Thirty-one breast carcinomas which showed the deletion of A/B/H type 2 expressed the Lewis-related antigens more frequently than nine cases which showed compatible expression. These results suggested that the activation of terminal fucosyltransferase and sialyltransferase as well as inactivation of some glycosyltransferases had occurred in cancer cell membrane, and sialyl Lex, defined by a new monoclonal antibody CSLEX1, may be useful as a tumor-associated antigen independent of Lewis blood group type in breast cancer.
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PMID:Immunohistochemical expression of blood group substances and related carbohydrate antigens in breast carcinoma. 190 2

The report describes results of separation of sialyltransferase isoenzymes by electrofocusing plasma from healthy volunteers and patients having different types of malignant tumour. Extensive modification of the technique was adopted in determining enzyme activity, such as elution of gel strips with the buffer pH corresponding to the gel focusing point; assessment of the effect of different pH on endogenous incorporation of radioactivity to desialated fetuin; and quantitative analysis of protein present in each gel band for calculation of enzyme activity. Plasma from normal individuals showed the existence of 5 sialyltransferase isoenzymes at pI 4.8, 5.5, 6.3, 6.8 and 7.5. There were higher isoenzyme activities in plasma samples from patients afflicted with malignancy of lungs and colon in comparison to normal pattern. Endometrial and breast cancer patients also showed elevated levels of the enzyme which could be controlled by surgery and combined therapies with cytotoxic drugs and radiation, respectively. The observations suggest the potential use of sialyltransferase as a tool for tumour diagnosis, and are discussed in relation to prognosis of the disease in the course of therapy.
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PMID:Elucidation of sialyltransferase as a tumour marker. 210 90

Galactosyltransferase (GalTF), sialyltransferase (SiaTF), fucosyltransferase (FucTF), 5'-nucleotidase (5'Nucl), and ADP-ribosyltransferase (RibTF) were determined in three subcellular fractions of tumor cells and adjacent control tissue from 20 patients with small primary infiltrating ductal adenocarcinomas of the breast. Viable, as pure tumor cell populations as possible were isolated, subfractionated, and their enzyme levels compared to those in the patients' sera. The activities in tumor cells of the three glycosyltransferases were two- to seven-fold higher, whereas 5'-Nucl and RibTF showed reduced activities when compared to adjacent noninvolved tissue. Serum GalTF and SiaTF were slightly elevated in early mammary carcinoma, whereas FucTF, 5'Nucl, and RibTF were decreased in comparison with a control group. The proposed tumor origin of circulating enzymes could not be confirmed. Surprisingly, only for RibTF could a correlation between tumor and serum activity be established; a weak correlation was found for SiaTF. However, no such relationship could be determined for GalTF, FucTF, or 5'Nucl. In conclusion, the enzyme profile of the tumor cell does not, except for RibTF, appear in the serum. Serum enzyme profiles, therefore, do not permit detection of the early stages of breast cancer. A high correlation between RibTF activity and cytosol estrogen and progesterone receptor levels has been determined in tumor cells, possibly indicating slower growing, more differentiated types of breast tumors.
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PMID:Enzyme activities in human breast tumor cells and sera. 299 19

Neoplastic transformations are accompanied by an alteration in the composition of cell membrane glycoproteins, major structural components of the cell surface. Plasma sialyltransferase enzyme is involved in the transfer of sialic acid residues from cytosine monophosphate (CMP) sialic acid to a suitable acceptor. In the present study plasma sialyltransferase was assayed using a radiometric method, which measured the transfer of radioactivity from (14C) CMP sialic acid to desialated fetuin. Plasma sialyltransferase was measured in 127 normal and 91 cancer patients. The mean plasma sialyltransferase in the normal volunteers was 837 units (CPM/25 microliters plasma/hr). The mean plasma sialytransferase in 26 breast cancer patients, 22 lung cancer patients, 20 colon cancer patients, 5 ovarian cancer patients, 4 cervix cancer patients, 5 pancreas cancer patients, 6 prostate cancer patients, and 3 gastrointestinal tract cancer patients was 1710, 1406, 1344, 1227, 1233, 1406, 1250, and 1426 units, respectively. No significant difference was observed with respect to age. In 32 treated breast cancer patients the mean value was 757 units. Serial determinations in 17 patients correlated well with tumor burden. However, in 2 patients the plasma enzyme level did not correspond to tumor mass. These results indicate that plasma sialyltransferase is significantly elevated in patients with a variety of cancers. Plasma sialyltransferase determination may be useful in the followup of patients with a variety of cancers.
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PMID:Plasma sialyltransferase as a tumor marker. 339 Aug 43

Sialyltransferase (CMP-sialic acid:asialofetuin sialyltransferase) and human mammary epithelial antigens (HME-Ags, cell surface antigens specific to human mammary epithelial cells) were determined in plasma of nude mice grafted with breast and non-breast human tumors to assess their possible usefulness as breast cancer markers. The plasma transferase activity was significantly higher (p less than 0.01) in tumor groups relative to the control. However, no significant difference (p less than 0.05) could be found in the transferase level between breast and non-breast tumor groups, showing the enzyme's lack of specificity for breast cancer. Furthermore, the surgical procedure performed on the control normal healthy group (no tumor), resulted in an important increase of the enzyme level, while HME-Ags remained unchanged. HME-Ags were essentially negative in control as well as non-breast tumor groups. After surgical removal of breast tumors, HME-Ags level dropped drastically to the background level (from 122 to less than 30 ng/ml plasma). These data indicate that HME-Ags are more sensitive and specific than sialyltransferase as markers for human breast tumor, and suggest that HME-Ags may be clinically useful in the early detection of breast cancer as well as in the followup of patients with metastatic breast tumor.
Breast Cancer Res Treat 1985
PMID:Breast cancer markers: comparison between sialyltransferase and human mammary epithelial antigens (HME-Ags) for the detection of human breast tumors grafted in nude mice. 397 47

Sialyltransferase and 5'-nucleotidase were measured in the sera of 135 women with breast cancer: 53 undergoing mastectomy for primary cancer and 83 receiving different modalities of palliative therapy for metastatic disease. The objective of this study was to determine whether these enzyme levels were associated with the extent of the disease and whether changes in these enzyme levels could be correlated with success or failure of treatment. Mastectomy caused a rapid fall of elevated enzyme levels to within the normal range in all patients with stage I breast cancer but not in those with stage II or III disease. In women with metastatic disease, elevated enzyme levels fell only in patients responding to treatment. Thus serum sialyltransferase and 5'-nucleotidase activities are reliable biomarkers of breast cancer activity, and serial measurement of these enzyme activities provides a useful tool for the monitoring of disease activity and success or failure of the treatment.
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PMID:Serum sialyltransferase and 5'-nucleotidase as reliable biomarkers in women with breast cancer. 625 2

Proteolytic and sialyltransferase activities were determined in extracts of 65 human primary breast tumors, 6 lymph node metastases, 6 fibroadenomas and 27 normal tissues. Using proteins and synthetic selective substrates, we observed the presence of collagen-peptidases, plasminogen activator, cathepsin-B and cathepsin-D-like enzymes, and sialyltransferase. No active or trypsin-activatable type-IV collagenase activity was detected. Although individual variations between tumors were large, proteinase and sialyltransferase contents were significantly elevated in malignant breast tissues. Enzyme activities were found to be related to the epithelial volume of the tumor. No significant correlation was found between the proteinase or sialyltransferase activities and the degree of differentiation of the tumor cells, or the degree to which tumors had metastasized to regional lymph nodes. Since large variations of enzyme levels apparently reflect the heterogeneity of epithelial cell densities in tumor samples, proteolytic or sialyltransferase activities cannot therefore be used as a measure of quantitative evaluation of invasive properties in breast cancer.
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PMID:Proteinases and sialyltransferase in human breast tumors. 632 71

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.
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PMID:Correlation between plasma carcinoembryonic antigen (CEA) and sialyltransferase as tumor marker. 659 15

Serum sialyltransferase (SST) activity was measured 10 days after mastectomy in 153 patients with operable breast cancer. Enzyme activity declined with time in storage (1-42 months). After correction for loss of activity in storage, patients with SST activity below the median value had a longer disease-free interval (DFI) than those with SST activity above the median, and this difference remained when patients were stratified by axillary nodal status, tumor size, and tumor grade. Survival was longer in patients with low SST activity. Post-operative elevation of SST indicates a poor prognosis in patients with operable breast cancer.
Breast Cancer Res Treat 1983
PMID:Post-operative serum sialyltransferase levels and prognosis in breast cancer. 661 79


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