Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.1.3.5 (5'-nucleotidase)
3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report a case of a neuroendocrine tumor of the jejunum metastatic to the liver in a 26-year-old woman. Light and electron microscopy of this tumor revealed a poorly differentiated neoplasm composed of clusters of round to polygonal cells compatible with a diagnosis of neuroendocrine tumor. In the absence of identifiable silver-staining granules or immunocytochemical demonstration of a specific hormone product in tumor cells, this tumor cannot be further classified among the various neuroendocrine tumors that may arise in this location. However, interspersed among tumor cells was a distinct population of multinucleate giant cells having an appearance similar to benign osteoclasts. Enzyme histochemistry for 5'-nucleotidase, acid phosphatase, and nonspecific esterase each showed a dichotomous staining pattern for the small tumor cells and giant cells and suggest that the giant cells are not tumor derived, but represent a second, presumably reactive, cell population.
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PMID:Malignant neuroendocrine tumor of the jejunum with osteoclast-like giant cells. Enzyme histochemistry distinguishes tumor cells from giant cells. 257 48

Osteosarcoma in the metaphysis to epiphysis of the left femur of a 17-year-old male is reported. The lesion appeared osteolytic with sclerotic foci on roentgenographs, accompanied by an extensive tumor shadow in the surrounding soft tissue. While 60% of the tumor was necrotic, histological examination of the remaining viable tissue revealed that it consisted almost entirely of a sheet of epithelioid cells, separated by thin, fibrovascular septa with an alveolar-like pattern, suggestive of metastatic carcinoma. Only a few areas were characterized by malignant osteoid tissue intermingled with the above cells, showing significant positivity for bone-specific alkaline phosphatase and 5'-nucleotidase, thus permitting a diagnosis of osteosarcoma. Autopsy findings revealed that the metastatic foci were histologically similar to those of the primary tumor. Electron microscopy revealed poor development of cytoplasmic organelles, supporting possible derivation from an osteoblastic cell lineage at an early stage.
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PMID:Osteosarcoma with prominent epithelioid features. 280 Nov 14

1. The cholesterol and phospholipid content of the surface membranes of ascites tumor cells cultivated in lipid-depleted medium was reduced to about 60(70)% of the control, but the relative composition of the individual phospholipids was not altered. 2. Differences in lipid composition were also observed between the two plasma membrane domains isolated from the cells cultured in normal and lipid-depleted medium respectively. 3. The fatty acid spectrum of the lipid-depleted membranes showed a greater fraction of saturated vs unsaturated acids. 4. The membrane lipid fluidity measured by fluorescence polarization was decreased in the modified surface membranes. 5. The 5'-nucleotidase specific activity was drastically reduced (46-66%) in the lipid-deleted membranes, and in addition its distribution between the two vesicle fractions was altered.
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PMID:Altered 5'-nucleotidase specific activity and distribution between two plasma membrane domains of ascites tumor cells with modified lipid composition. 283 Jan 54

LM fibroblasts grown in a chemically-defined, serum-free medium readily incorporated choline or one of three analogues of choline, namely N,N-dimethylethanolamine, N-monomethylethanolamine, or ethanolamine into membrane phospholipids. The effect of these phospholipid manipulations in vitro on tumor growth and metastasis was examined in nude mice. Serum and choline-fed cells most frequently metastasized (74% and 68%, respectively), while frequency of lung metastasis was 46%, 42% and 17% in mice injected with cells fed with dimethylethanolamine, monomethylethanolamine, and ethanolamine, respectively. Metastases from cells cultured with serum, choline or dimethylethanolamine, but not from monomethylethanolamine or ethanolamine, were extensive and highly invasive. The specific activity of the (Na+ + K+)-ATPase but not of 5'-nucleotidase was significantly decreased in local tumor plasma membranes from choline analogue-fed cells as compared to tumor plasma membranes from choline-fed cells. When compared to the choline-fed tumor cells, the specific activities of three mitochondrial enzymes, namely NADH dependent, rotenone insensitive NADH-dependent, and rotenone sensitive NADH-dependent cytochrome-c reductase, were significantly increased in the choline analogue-supplemented cells. The arachidonic acid content of phosphatidylcholine in plasma membranes, microsomes, and mitochondria was significantly decreased in tumor membranes from choline analogue-fed cells as compared to tumor membranes from choline-fed cells. As compared to local tumor plasma membranes, the lung metastasis plasma membranes had elevated (Na+ + K+)-ATPase specific activity, phospholipid oleic and arachidonic acid content, and fluidity. In contrast, the 5'-nucleotidase specific activity, the content of cholesterol, phospholipid, and phosphatidylethanolamine were decreased in lung metastasis plasma membranes. In summary, membrane alterations of LM tumor cells in vitro (1) were not completely reversed in vivo, and (2) affected metastatic ability.
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PMID:Local and metastatic tumor growth and membrane properties of LM fibroblasts in athymic (nude) mice. 283 81

The sensitivity to photodynamic treatment of three plasma membrane enzymes in R3230AC mammary adenocarcinomas was assessed. The activities of Na+K+-ATPase, Mg2+-ATPase and 5'-nucleotidase in isolated membranes were measured after exposure of membranes to either hematoporphyrin derivative or Photofrin II plus light in vitro or in tumor membranes prepared from animals previously injected with 25 mg/kg Photofrin II and sacrificed at various times prior to exposure to light (in vivo-in vitro protocol). The activities of both Na+K+-ATPase and Mg2+-ATPase were inhibited at equivalent rates by Photofrin II in vitro; inhibition was drug dose and light dose related. For 5'-nucleotidase in vitro, a 10-fold higher porphyrin concentration was required to achieve a similar rate of enzyme inhibition as that for the ion-activated ATPases. Injection of Photofrin II in vivo followed by preparation of tumor plasma membranes, which were subsequently exposed to light in vitro, produced no photosensitization of 5'-nucleotidase activity at any time studied (up to 72 h after Photofrin II administration). Under the same conditions Na+K+-ATPase activity was reduced by 40-60% from 2 to 72 h after drug injection, whereas Mg2+-ATPase activity was inhibited by 10-25% over the same time course. The differential sensitivity of these three enzymes observed in this in vivo-in vitro protocol suggests that each enzyme may possess different characteristics, such as three-dimensional configuration or membrane location, that afford varying susceptibility to porphyrin photosensitization. The data also suggest that photosensitivity-induced damage to these ion-activated plasma membrane ATPases could have deleterious effects on tumor cell survival.
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PMID:Photosensitizing effects of hematoporphyrin derivative and photofrin II on the plasma membrane enzymes 5'-nucleotidase, Na+K+-ATPase, and Mg2+-ATPase in R3230AC mammary adenocarcinomas. 283 53

To determine whether the mononuclear cells (MC) and multinucleated giant cells (GC) of giant cell tumor of tendon sheath (GCTTS) exhibit evidence of monocyte/macrophage lineage, we studied their antigenic features (seven cases, paraffin sections; two cases, frozen sections) and enzymatic features in situ (four cases, plastic sections). Both MC and GC expressed a monocyte/macrophage phenotype: HLA-A,B,C+, HLA-DR+, T200+ (leukocyte common antigen), Leu-M3+ and Leu-3+. MC and GC also expressed similar enzymatic phenotypes which resembled that of osteoclasts. Both were rich in acid phosphatase and contained smaller, variable amounts of ATPase, beta-glucuronidase, alpha-naphthyl acetate esterase, and 5'-nucleotidase. Both lacked alkaline phosphatase. Reactive osteoclasts in plastic and paraffin sections were also T200+, a finding strongly supporting their bone marrow derivation and leukocytic differentiation. In plastic sections, osteoclasts were additionally reactive with macrophage antigen EBM11. In aggregate, these data suggest that GCTTS is a true histiocytic lesion of monocyte/macrophage lineage composed of phenotypically similar MC and GC that most closely resemble osteoclasts. We found no evidence that GCTTS cells resemble osteoblasts, fibroblasts, or synovial sarcoma cells. Furthermore, expression of the Ki-67 nuclear antigen by 1-2% of MC but not by GC suggests that the proliferating cells in GCTTS are restricted to its MC component.
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PMID:The cells of giant cell tumor of tendon sheath resemble osteoclasts. 283 1

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

The cell-surface enzyme 5'-nucleotidase in microvilli from 13762 rat mammary adenocarcinoma cells remains largely associated with microfilament-containing high-speed pellets from Triton X-100 extracts of the microvilli. The fraction remaining with the insoluble portion is higher under ionic conditions which enhance microfilament stability. To minimize trapping and cosedimentation we have analyzed the distribution of microfilaments and 5'-nucleotidase activity on velocity sedimentation sucrose gradients of the microvillar extracts. A large fraction of the total enzyme activity is found in the filament fractions in the middle of the gradient. When phalloidin is included in the extraction buffer to stabilize the microfilaments, both the microfilaments and the bulk of the nucleotidase activity are shifted further into the gradients. Both the position of the filament fraction and the percentage of the total nucleotidase activity remaining with the filament fraction varies with extraction buffer composition and conditions. Nonetheless, under all conditions tested, a large percentage of the activity was shifted, along with the microfilaments, in the presence of phalloidin. These results are consistent with a specific association of 5'-nucleotidase with microfilaments in the ascites tumor cell microvilli.
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PMID:Demonstration of the association of the cell-surface enzyme, 5'-nucleotidase, with microvillar microfilaments by phalloidin shift on velocity sedimentation gradients. 300 89

A purified preparation of macrophage colony-stimulating factor (M-CSF) free of interferon and endotoxin activity was studied for its effects on resident murine peritoneal macrophages. M-CSF was found to induce profound morphologic alterations in resident macrophages. These changes included a marked increase in cell size, membrane ruffling, and cytoplasmic vacuolization. Further, after 72 hr of incubation with 1000 U/ml of M-CSF, there were significant increases in macrophage DNA synthesis as measured by autoradiography (P less than 0.001), and in macrophage monolayer protein content (P less than 0.01). None of these changes was seen in control macrophages or those exposed to recombinant interferon-gamma (IFN). Low activity levels of the ectoenzymes 5'-nucleotidase (5'NTD) and alkaline phosphodiesterase I (APD) have been associated with certain macrophage functions, particularly the expression of tumor cytotoxicity. Macrophage monolayers exposed to M-CSF demonstrated an unaltered level of 5'NTD activity from controls and a significantly increased level of APD activity (P less than 0.01) and did not demonstrate an increased ability to kill tumor cells, as measured by the 51Cr-release assay. On the other hand, IFN caused significant decreases in both 5'NTD (P less than 0.05) and APD (P less than 0.01) and also induced marked tumoricidal activity in macrophage monolayers. These results indicate that purified M-CSF induces highly specific alterations in the functional activity and morphologic appearance of resident macrophages and these changes are distinct from those induced by IFN.
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PMID:Stimulatory effects of purified macrophage colony-stimulating factor on murine resident peritoneal macrophages. 301 77

Activities of key enzymes of purine metabolism [adenosine deaminase (AD); purine nucleoside phosphorylase (PNP); 5'-nucleotidase] were studied; changes in DNA content, nucleus ploidity in thymocytes, T- and B-lymphocytes in the C3HA mouse spleen during solid 22 hepatoma growth and after the immunization were monitored. Immunological properties of lymphocytes were also investigated measuring antibody formation and the reaction of blasttransformation in response to phytohemagglutinin, concanavalin A and lipopolysaccharide. Within the first 48 hrs after the tumor implantation and immunization certain nonspecific biochemical mechanisms of lymphocytes activation (elevated AD activity, decreased activity of 5'-nucleotidase, augmented intracellular DNA levels, polyploidity) were revealed. As the solid 22 hepatoma reached the maximum growth rate specific alterations in the activities of the purine metabolism key enzymes were observed reflecting the response of thymus and spleen lymphocytes to the presence of the malignant tumor.
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PMID:[Biochemical and functional characteristics of thymus and spleen lymphocytes in C3HA mice during the growth of hepatoma 22 and after immunization with sheep erythrocytes]. 302 Jul 91


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