Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fifty-one patients (16 with malignant extrahepatic biliary obstruction, ten with benign extrahepatic biliary obstruction, eight with alcoholic liver disease, five with viral hepatitis and 12 with liver metastases) and 19 adult healthy controls were studied with determinations of beta-N-acetyl hexosaminidase (a lysosomal enzyme which is cleared from the circulation by the Kupffer cells), carcinoembryonic antigen (CEA), serum bilirubin, alkaline-phosphatase and aspartate aminotransferase (AST). Both CEA and beta-NAH were elevated in each disease group. Elevated beta-NAH levels distinguished between benign and malignant extrahepatic biliary obstruction better than CEA levels. Beta-NAH levels for the malignant and the benign groups were 47.6 +/- 14.7 U/l and 23.0 +/- 4.7 U/l (mean +/- S.D.) respectively. The groups differed significantly (P less than 0.001). Plasma CEA levels for both groups were 18.7 +/- 38.9 and 7.2 +/- 3.3 ng/ml (mean +/- S.D.) respectively. Beta-NAH levels for the 19 normal controls were 15.8 +/- 3.5 U/l (mean +/- S.D.). Beta-NAH also was significantly elevated in patients with hepatic metastases (36.9 +/- 20.1 U/l). In 25 cancer patients with metastases other than in the liver beta-NAH levels (18.3 +/- 5.2) were not significantly elevated over the control group. It has potential value as a marker for non-CEA-producing liver metastases.
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PMID:Serum beta-N-acetyl hexosaminidase (beta-NAH) as a discriminant between malignant and benign extrahepatic biliary obstruction: comparison with carcinoembryonic antigen (CEA). 293 60

Penetration of the extracellular matrix (ECM) by tumor cells, an event which occurs at various stages of the metastatic process, involves tumor cell glycosidase mediated hydrolysis of proteoglycans (PG). Recently, we observed that human ovarian carcinoma cell lines (HOCC) derived from primary tumors, peritoneal effusions, and distant metastases possess a varying ability to degrade radiolabeled PG of the ECM, while normal cells (human mesothelial cells or ovarian fibroblasts) fail to do so. To determine whether a quantitative relationship exists between glycosidase activity and degradation of ECM, both intracellular and extracellular glycosidase activities were measured for HOCC and normal cell lines. No relationship was found between intracellular glycosidase activities and the ability of cells to degrade ECM. However, a correlation was observed between extracellular or secretory glycosidase activities and HOCC mediated ECM degradation. In particular, a 5-8-fold increase, as compared to normal cells, was observed for HOCC extracellular beta-N-acetylglucosaminidase (EC 3.2.2.30) activity. The accumulation or secretion of this enzyme from HOCC into culture medium was found to be time dependent and not related to intracellular levels. Purified hexosaminidase derived from invasive HOCC was able to hydrolyze [3H]-glucosamine radiolabeled ECM (up to 30% radiolabel) and resulted in the cumulative release of free [3H]-N-acetylglucosamine. This enzyme mediated hydrolysis could be completely prevented with 2-acetamido-2-deoxy-1,5-D-gluconolactone, a competitive inhibitor (Ki 10(-6) M). Finally, HOCC mediated degradation of radiolabeled ECM was discerned to be dependent upon active hexosaminidase action, since tumor cell mediated degradation of ECM could be inhibited by up to 60% in the presence of this synthetic competitive inhibitor. In summary, these studies indicate a strong association between HOCC solubilization of glycoconjugates present in the ECM and extracellular levels of hexosaminidase.
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PMID:Role of glycosidases in human ovarian carcinoma cell mediated degradation of subendothelial extracellular matrix. 295 46

Glycosidases have been demonstrated to be elevated in the interstitial fluid of tumors, sera of animals and patients with tumors, and in some tumor tissue as compared to normal adjacent tissue. Elevations of serum beta-N-acetylglucosaminidase and beta-glucuronidase most commonly have been found to occur and these enzymes have been shown to be secreted into the extracellular medium by many different tumor cell types in vitro. The mechanism of cellular release of these hydrolytic enzymes probably involves tumor lysosomal exocytosis. Increased tumor glycosidase levels may promote increased tumor cell shedding from primary tumors, local invasion and perhaps be responsible directly, or indirectly for structural changes in tumor cell surface glycoconjugates. These cell surface changes could facilitate tumor cell thrombus formation, secondary site implantation and attachment in the microcirculation to endothelial cells and/or subendothelial basement membrane components. Other studies have demonstrated a correlation between metastatic cell potential and increased endoglycosidase and polysaccharide lyase activity. Generally, metastatic tumor cell variants have been found to be more invasive and capable of degrading proteoglycan basement membrane components, in part due to these increased levels of degradative enzymes. Hence, it is of considerable interest to develop inhibitors against these enzymes. Initial studies with glucuronidase inhibitors in the therapy of bladder tumors have been promising and with the advent of better agents and the use of appropriate in vitro metastatic models it may be possible to design and develop agents which interfere in various metastatic events and limit tumor progression.
Cancer Metastasis Rev 1985
PMID:Glycosidases in cancer and invasion. 388 85