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)

The metabolism of deoxycytidine (dCyd) and dCyd nucleotides in Yoshida ascites sarcoma (YS) cells and the host rat liver was investigated with reference to the increased excretion of urinary dCyd. Incorporation of [14C]orotic acid into the livers of rats at the fifth day after the transplantation of YS cells, the time when the amount of excretion of dCyd in urine was near maximal, was 2 times higher than that into the normal rat livers. After the injection of [14C]orotic acid, the ratio of the specific radioactivity of cytidylate to uridylate moieties of the host liver RNA was measured and found to be higher than that of normal rat liver RNA and to be similar to that of YS cell RNA. When [14C]orotic acid was injected into rats followed by the transplantation of YS cells, the radioactivities present in the livers disappeared more rapidly than those in the control rat livers. The activities of pyrimidine de novo synthesis enzymes, such as cytidine triphosphate synthetase (EC 6.3.4.2) and cytidine diphosphate reductase (EC 1.17.4.1), in YS were higher than those in both rat ascites hepatoma AH 7974 and Walker 256 carcinosarcoma, the transplantations of which did not induce increased excretion of dCyd into urine of the hosts. The activities of dCyd kinase (EC 2.7.1.10) and dCyd deaminase (EC 3.5.4.5) in YS cells were lower than those in the other two tumors investigated. The activities of cytidine triphosphate synthetase and cytidine diphosphate reductase in the livers of YS-bearing rats were elevated compared with those in the livers of rat ascites hepatoma AH 7974- or Walker 256 carcinosarcoma-bearing rats and normal rats, while the activities of dCyd kinase, 5'-nucleotidase (EC 3.1.3.5), and dCyd deaminase were similar between normal rat livers and tumor-bearing rat livers. These results suggest that the increased excretion of urinary dCyd in YS-bearing rats could be caused by both the stimulation of the synthesis of dCyd nucleotides and the low activity of dCyd deaminase in YS cells as well as in the host liver.
Cancer Res 1984 Jun
PMID:Origin of increased deoxycytidine excretion into urine of rats bearing Yoshida ascites sarcoma. 672 78

Plasma membranes were isolated from lymphoid cells of benign thymomas obtained from inbred BUF/Mna rats (21 mo old) and from normal thymocytes obtained from young rats (7 wk old) of the same strain. The isolated plasma membranes were electron microscopically pure, and the specific activities of Na+, K+-ATPase, and 5'-nucleotidase were enhanced. The lipid compositions of the plasma membranes from these two sources were analyzed and compared. The cholesterol and plasmalogen contents of membranes from both sources were similar, but the phospholipid content of the benign thymoma lymphoid cell membranes was slightly lower than that of the normal thymocytes, resulting in a somewhat higher molar ratio of cholesterol to phospholipid. The plasma membranes of the thymoma lymphoid cells also exhibited a slightly higher microviscosity as measured with fluorescence polarization. No significant differences were observed in the phospholipid compositions of the two membrane preparations.
J Natl Cancer Inst 1980 Oct
PMID:Lipid analysis of isolated plasma membranes of lymphoid cells in benign thymomas of Buffalo/Mna rats. 693 30

Our knowledge of prostate cancer is less well-defined than our knowledge of cancers of other organs. In the colon, for example, morphological criteria to identify carcinomas in situ and some putative preneoplastic lesions are clear; phenotypic differences in the expression of enzymes and antigens are documented in experimental models and are starting to be defined in humans. Experimental models of cancer of the liver and colon show evidence that "enzyme-altered foci" are preneoplastic. In these organs, the "normal" context is much clearer than in the prostate. In contrast, in the prostates of men in the same age range as those who develop prostate cancer, morphological aberrations are almost always present, diverse, and poorly understood. Murphy and Gaeta said that, "in the study of prostatic disease..., almost every aspect remains controversial...[and].... many of the 'known facts' concerning prostatic disease are poorly documented..." While being aware that the definitions of all benign and malignant lesions of the prostate are based on complex morphological criteria which must form the contemporary context for comparisons, our laboratory is searching for markers that will permit the identification of putative preneoplastic lesions in the prostate. In our opinion, these changes will not be found most efficiently, if they are present at all, in long established cell lines, advanced carcinomas, or serially transplantable xenografts of primary prostatic carcinomas. Our preliminary data suggest that several enzyme histochemical and immunohistochemical approaches are worthy of study. Markers that show promise include acid phosphatase, 5'-nucleotidase, leucine aminopeptidase, and CD44.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Putative preneoplastic foci in the human prostate. 752 54

"Chondroid chordoma" is a controversial and confusing entity that was originally described by Heffelfinger and colleagues as a biphasic malignant neoplasm possessing elements of both chordoma and cartilaginous tissue. Because the premise for this distinction was based strictly on histomorphologic criteria, the light microscopic, immunohistochemical, and electron microscopic features of the chondroid and chordoid areas of five chondroid chordomas of the skull base were evaluated separately, and compared to five typical chordomas and six low grade chondrosarcomas. Using light microscopy, chondroid chordoma revealed areas that resembled typical chordoma (chordoid areas) and areas that resembled low grade chondrosarcoma (chondroid areas). However, both the chordoid and chondroid areas had an epithelial phenotype and stained strongly for cytokeratin and EMA as well as S-100. 5'-nucleotidase, an enzyme that has been described in chordoma but not in chondrosarcoma, was found in both the chordoid and chondroid areas of one chondroid chordoma. Electron microscopic studies of both the chordoid and chondroid areas in four of the tumors demonstrated both tonofibrils and desmosomes. Chordoma demonstrated immunohistochemical and electron microscopic features that were nearly identical to chondroid chordoma. Chordoma was cytokeratin, EMA, S-100, and 5'-nucleotidase positive. Ultrastructurally, chordoma exhibited variably-sized vacuoles, abundant rough endoplasmic reticulum (RER), and desmosomes with tonofilaments. In contrast to chondroid chordoma, chondrosarcoma consistently stained for only S-100 protein and was cytokeratin, EMA and 5'-nucleotidase negative. Ultrastructurally, chondrosarcoma demonstrated a flocculogranular matrix, glycogen, abundant RER, and scalloped cellular outlines, but lacked desmosomes with tonofilaments. These findings indicate that "chondroid chordoma" is a variant of chordoma with histologic features that may mimic chondrosarcoma. Despite the resemblance of these hyalinized areas to cartilaginous tissue, these tumors retain their epithelial phenotype. Biphasic differentiation is not present. These findings undermine the original premise for distinguishing "chondroid chordoma" from typical chordoma. The authors propose that these tumors be classified as "hyalinized chordomas," rather than "chondroid chordoma," to clarify their histogenesis and avoid confusion with chondrosarcomas of the base of the skull.
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PMID:Chondroid chordoma. A hyalinized chordoma without cartilaginous differentiation. 757 5

Serum levels of adenosine deaminase (ADA), 5-nucleotidase (5'-NT) and alkaline phosphatase (ALP) were studied in 25 patients of carcinoma breast and 25 normal subjects. Adenosine deaminase was found to be the better probable parameter for the detection of cancer and to assess the development of various stages of cancer whereas 5'-nucleotidase had only diagnostic significance. Serum alkaline phosphatase levels were important for assessing the spread of cancer at secondary sites. After mastectomy a significant decrease was found in the levels of serum ADA and 5'-NT whereas no variations were found in case of serum ALP.
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PMID:Serum adenosine deaminase, 5'-nucleotidase & alkaline phosphatase in breast cancer patients. 767 35

A large series of samples obtained after surgical resection of intestinal mucosa of patients affected by intestinal carcinoma was examined in order to define possible relationships between levels of enzymes involved in the purine salvage pathway and clinical/biological parameters of aggressiveness and invasiveness. The results confirm our previous observation on a different pattern of purine salvage enzymes in tumor as compared to normal colon tissues (Camici et al., 1990). In fact, we observed in human colon tumor tissues a significant enhancement of the three enzymes involved in the synthesis of IMP, hypoxanthine guanine phosphoribosyltransferase (HGPRT), adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP). On the other hand, no variation was observed in the 5'-nucleotidase and alkaline phosphatase activities. While we could not find a significant correlation between HGPRT, ADA and PNP activities and histologic grading or biological parameters of tumor aggressiveness, the significant correlation with the extent of disease, as expressed by the Dukes' stage, would demonstrate at least for human colon tumors, a relationship between enzyme activity and tumor invasiveness.
Cancer Biochem Biophys 1994 Apr
PMID:Relationship between the levels of purine salvage pathway enzymes and clinical/biological aggressiveness of human colon carcinoma. 779 89

The effects of the differentiation-inducing agents sodium butyrate (NaOBt), dimethylsulfoxide (DMSO) and mycophenolic acid (MA), on purine nucleotide metabolism, was studied in an ovarian carcinoma cell line (GZL-8). Exposure to these agents inhibited cell proliferation, but did not affect cell viability. Three hours following exposure, NaOBt and DMSO moderately decelerated purine synthesis de novo, but MA accelerated it three-fold, this being associated with a two-fold increase in the excretion of hypoxanthine and xanthine into the incubation medium. NaOBt and DMSO did not affect the cellular nucleotide content, but MA caused a 73% decrease in GTP content and about a 50% increase in the cellular content of UTP. The following alterations in cellular enzyme activity were observed 72 h following exposure: NaOBt decreased the activity of hypoxanthine-guanine phosphoribosyltransferase and increased the activity of IMP and of AMP 5'-nucleotidases, DMSO increased the activity of IMP 5'-nucleotidase, and MA increased the activity of the two nucleotidases. The results suggest that, in the carcinoma cell line studied, the differentiation process induced by NaOBt and DMSO may be associated with a general shift in the direction of purine metabolism from anabolism to catabolism, whereas that induced by MA is associated with a specific decrease in the production of GTP.
J Cancer Res Clin Oncol 1994
PMID:Effects of differentiation-inducing agents on purine nucleotide metabolism in an ovarian cancer cell line. 779 96

The activities of some of the enzymes participating in nucleotide metabolism were measured in cancerous and noncancerous gastric tissues from patients with gastric cancer. The enzyme activities measured were found to be higher in the cancerous tissues than in the non-cancerous tissues. Adenosine deaminase (ADA), 5'-nucleotidase (5'-NT), guanase (GUA) and cytidine deaminase (CD) activities in the cancerous tissues were 56.0 +/- 24.0, 45.0 +/- 20.0, 0.34 +/- 0.16 and 4.65 +/- 2.04, respectively. The activities in non-cancerous tissues were 13.2 +/- 6.0, 19.8 +/- 8.3, 0.12 +/- 0.06 and 1.65 +/- 0.8, respectively. Cancerous tissues consisted of 7 gastric tissues with Grade I-II and 8 tissues with Grade III-IV adeno cancer. Non-cancerous adjacent tissues were obtained from the same patients with Grade I-II cancer. There were no meaningful differences between enzyme activities of the gastric tissues with Grade I-II and Grade III-IV cancer. Enzyme activity ratios indicates that ADA activity increased by the highest amount relative to other enzyme activities in the cancerous tissues. In the correlation analysis, we found positive correlations between some of the enzyme activities in the cancerous tissues. Results suggest that increased activities of these enzymes might play a part in the accelerated nucleotide metabolism in the cancerous gastric tissues.
Cancer Lett 1994 Sep 15
PMID:Adenosine deaminase, 5'-nucleotidase, guanase and cytidine deaminase activities in gastric tissues from patients with gastric cancer. 807 77

Metastases in rat liver were generated experimentally by intraportal injection of colon cancer cells to investigate the effects of cancerous growth on the metabolism of surrounding liver tissue. Maximum activities (capacity) of glucose-6-phosphate dehydrogenase, phosphogluconate dehydrogenase, lactate dehydrogenase, succinate dehydrogenase, alkaline phosphatase, 5'-nucleotidase, xanthine oxidoreductase, purine nucleoside phosphorylase and adenosine triphosphatase have been determined. Two types of metastases were found, a small type surrounded by stroma and a larger type in direct contact with hepatocytes. Both types affected the adjacent tissue in a similar way suggesting that the interactions were not mediated by stroma. High capacity of the degradation pathway of extracellular purines released from dead cells of either tumours or host tissue was found in stroma and sinusoidal cells. Metastases induced both an increase in the number of Kupffer cells and proliferation of hepatocytes. The distribution pattern in the liver lobulus of most enzymes investigated did not change distinctly. However, activity of alkaline phosphatase, succinate dehydrogenase and phosphogluconate dehydrogenase was increased in hepatocytes directly surrounding metastases. These data imply that the overall metabolic zonation in liver lobuli is not dramatically disturbed by the presence of cancer cells despite the fact that various metabolic processes in liver cells are affected.
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PMID:Experimentally induced colon cancer metastases in rat liver increase the proliferation rate and capacity for purine catabolism in liver cells. 822 8

A preliminary investigation of enzymes functioning at the cell surface indicates that when Walker 256 carcinoma cells growing ascitically are induced to grow as a solid tumour there is a marked increase in the activities of Na+, K(+)-ATPase, Mg(2+)-ATPase, 5'-nucleotidase, alkaline phosphatase and phosphodiesterase I; 5'-nucleotidase and alkaline phosphatase being particularly affected. These enzyme changes occur in the absence of any major alteration in the protein composition of the plasma membrane.
Cancer Lett 1993 Feb
PMID:Protein and enzyme content of plasma membranes derived from Walker 256 carcinoma cells grown as ascitic or solid tumours. 838 3


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