Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20020 (adenosine triphosphatase)
 3,299 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The authors describe a 63-year-old woman who developed a histologically distinctive malignant cutaneous neoplasm composed of large pleomorphic cells with abundant cytoplasm and multilobate, often clefted nuclei that occasionally contained small nucleoli. This neoplastic cell population metastasized to a regional lymph node already involved by a B-cell derived chronic lymphocytic leukemia expressing surface IgMk, BA-1, and OKT1. The large metastatic tumor cells lacked surface immunoglobulin, B-lymphocyte associated antigen BA-1, T-lymphocyte associated antigens OKT1 and OKT3, and the monocyte/macrophage markers lysozyme and alpha 1-antichymotrypsin. These tumor cells expressed HLA-DR antigens, adenosine triphosphatase (ATPase), OKT6, and contained S-100 protein, i.e., they expressed the phenotype peculiar to epidermal Langerhans cells. The typical clinical and histologic features of Histiocytosis X were absent. Thus, this case appears to represent a distinctive cutaneous neoplasm composed entirely of malignant cells of dendritic cell origin which, by immunophenotypic and histochemical analysis, appear to be related to epidermal Langerhans cells.
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PMID:A distinctive cutaneous malignant neoplasm expressing the Langerhans cell phenotype. Synchronous occurrence with B-chronic lymphocytic leukemia. 388 25

A case of glomus tumor was studied by light and electron microscopic enzyme histochemistry. Histologically, this case was classified as glomangioma or vascular form of glomus tumor. The tumor cells had ultrastructural characteristics of smooth muscle cells such as large amount of thin filaments with dense bodies, basal lamina and numerous pinocytotic vesicles. Among the 3 membrane associated enzymes, namely alkaline phosphatase, adenosine triphosphatase (ATPase) and 5'nucleotidase, only ATPase was detectable in the cell membrane and pinocytotic vesicles. It is suggested that the ATPase activity of the tumor cells shows additional evidence of smooth muscle character of glomus tumor.
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PMID:Histochemical evidence of adenosine triphosphatase activity in glomus tumor--report of a case. 609 31

Comparative studies of enzyme activities during the dedifferentiation of hepatic cells and through their development into overt hepatomas are few and contradictory. This study was designed to investigate the histochemical, biochemical and morphologic features of the altered liver cells with particular emphasis on the importance and validity of the histoenzymatic behavior of glucose-6-phosphatase (G6Pase) as a marker for the detection of precancerous hepatic cells. Serum and hepatic levels of G6Pase were analyzed and compared with the histoenzymatic behavior of this enzyme. The use of other enzymes, such as adenosine triphosphatase (ATPase) and gamma glutamyl-transpeptidase (GGT) as histochemical markers for malignancy was also tested. The activities of a variety of enzymes commonly used as diagnostic tools were also evaluated in both the liver homogenates and sera of rats treated with 2 mg diethylnitrosamine (DENA)/kg body weight for 2-28 weeks. Using G6Pase as a histoenzymatic marker, precancerous cells appeared after 4 weeks of exposure to DENA in the form of small islets devoid of G6Pase activity. These G6Pase free cells increased in number forming larger islands and finally appeared as tumor nodules after 28 weeks of treatment. The histoenzymatic behavior of ATPase was identical to that of G6Pase. The precancerous cells, as well as the tumor cells appeared devoid of ATPase activity. The application of GGT as a marker, showed significantly increased activity in the altered liver and tumor cells. Increased serum levels of G6Pase were noted after 10 weeks and were greatly elevated in the late stages of the evolution of the precancerous cells.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Serum and hepatic enzyme activity in rats treated with diethylnitrosamine. 610 Feb 19

Ultracytochemical study was made of inosine diphosphatase (IDPase) and adenosine triphosphatase (ATPase) in the nuclei of normal epithelial and cancer cells of human gastric tumors. A new incubation medium for ultracytochemical demonstration of IDPase activity in the cell nuclei was developed. The activity of IDPase and ATPase in the nucleoplasm and in the nucleoli of the tumor cells was shown to be lower than in respective normal cells. IDPase activity in the nuclear envelope in the tumor cells was absent in contrast to the normal cells.
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PMID:[Ultracytochemical study of the nucleoside phosphatase activity of nuclei of epithelial cells of the gastric mucosa and of stomach cancer cells in humans]. 610 95

Characteristic alterations of marker enzymes and tumor-associated antigens have been detected in the preneoplastic lesions of experimental hepatocarcinogenesis. An identical pattern of enzyme activity (increased gammaglutamyl transferase, loss of glucose-6-phosphatase, and canalicular adenosine triphosphatase) was demonstrated in a case of nodular "regenerative" hyperplasia of liver. The lack of marker antigens (alphafetoprotein, carcinoembryonic antigen, alpha 1-antitrypsin) in the hyperplastic nodules in this patient may be related to the discontinuation of oral contraceptive steroids four years earlier. The phenotypic changes of enzyme activity suggest that nodular "regenerative" hyperplasia of the liver in man is preneoplastic.
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PMID:Enzyme pattern and marker antigens in nodular "regenerative" hyperplasia of the liver. 611 60

Purified plasma membranes were obtained from five transplantable human tumors, a grade IV astrocytoma, an oat cell carcinoma, and three melanomas. Plasma membrane fractions were isolated from tumor homogenates by differential and discontinuous sucrose gradient centrifugation. Determination of enzyme activities indicated that the plasma membranes were enriched 10- to 20-fold with respect to 5'-nucleotidase, nicotinamide adenine dinucleotide glycohydrolase, Mg2+-activated nucleoside triphosphatase, and sialic acid. Specific activities of nearly all the enzymes varied with the individual tumors, even among tumors of the same type, i.e., the melanomas. Electron micrographs of the plasma membrane fractions showed smooth single-membrane vesicles with slight contamination by lysosomes. Therefore, these membranes are suitable for comparative biochemical studies and for the preparation of tumor-specific monoclonal antibodies. Plasma membranes from all five tumors contained very high Mg2+-adenosine triphosphatase (ATPase) activities. The Na+-K+-ATPase was a minor component of the total ATPase of these membranes (less than 30%). The major component was an ATPase exhibiting similar activity toward several nucleoside triphosphates. The activity of such a nucleoside triphosphatase has been correlated with tumorigenicity in cultured liver epithelial cells. The nucleoside triphosphatase of the plasma membranes of astrocytoma and oat cell carcinoma was stimulated from 50 to 1005 by concanavalin A, whereas ATPase of the melanoma plasma membranes was not or only slightly stimulated. The different response to concanavalin A could be due to differences in the ATPase molecules of the individual tumors or to the different environment of the ATPase.
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PMID:Isolation and characterization of plasma membranes from transplantable human astrocytoma, oat cell carcinoma, and melanomas. 611 38

In order to get precise information about the movement of plasma membrane proteins in cap formation, cyto- and bio-chemical analyses were made of the plasma membranes from non-capped areas of Ehrlich ascites tumor cells (EATCs) exposed to concanavalin A (Con A). Blebs formed by treatment with cytochalasin B (CB) of the non-capped areas of cells having a cap were isolated and used as the plasma membranes from non-capped areas (ConA-CB-bleb fraction). This bleb fraction was compared with a bleb fraction prepared from cells without ConA-treatment (CB-bleb fraction). Cytochemical analysis of ConA-CB-bleb fraction revealed a decreased in conA binding sites (ConA-BS) compared to the CB-bleb fraction. SDS polyacrylamide slab gel electrophoresis also revealed a decrease in the major components of ConA-BS of the ConA-CB-bleb fraction. The minor components of ConA-BS showed no distinct quantitative difference between the ConA-CB-bleb and CB-bleb fractions. NA+ K+-adenosine triphosphatase (ATPase), 5' nucleotidase (5'ND) and gamma-glutamyl transpeptidase (gamma-GTP) did not show any decrease in activity in the ConA-CB-bleb fraction, but the activity of D+-stimulated phosphatase (K-Pase) was decreased. The findings indicate that there are two types of plasma membrane glycoproteins in EATCs; one includes those participating in cap formation due to ConA, e.g. the major components of ConA-BS and K-Pase, and the other, those not participating in such cap formation, e.g. some minor components of ConA-BS, ATPase, 5'ND and gamma-GTP, which keep their places without moving.
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PMID:Movement of plasma membrane proteins of Ehrlich ascites tumor cells in relation to cap formation induced by concanavalin A: a study on the non-capped areas. 611 90

A unique cytoplast preparation from Ehrlich ascites tumor cells (G. V. Henius, P. C. Laris, and J. D. Woodburn (1979) Exp. Cell. Res. 121, 337-345), highly enriched in plasma membranes, was employed to characterize the high-affinity plasma membrane calcium-extrusion pump and its associated adenosine triphosphatase (ATPase). An ATP-dependent calcium-transport system which had a high affinity for free calcium (K0.5 = 0.040 +/- 0.005 microM) was identified. Two different calcium-stimulated ATPase activities were detected. One had a low (K0.5 = 136 +/- 10 microM) and the other a high (K0.5 = 0.103 +/- 0.077 microM) affinity for free calcium. The high-affinity enzyme appeared to represent the ubiquitous high-affinity plasma membrane (Ca2+ + Mg2+)-ATPase (calcium-stimulated, magnesium-dependent ATPase) seen in normal cells. Both calcium transport and the (Ca2+ + Mg2+)-ATPase were significantly stimulated by the calcium-dependent regulatory protein calmodulin, especially when endogenous activator was removed by treatment with the calcium chelator ethylene glycol bis(beta-aminoethyl ether) N,N'-tetraacetic acid. Other similarities between calcium transport and the (Ca2+ + Mg2+)-ATPase included an insensitivity to ouabain (0.5 mM), lack of activation by potassium (20 mM), and a requirement for magnesium. These similar properties suggested that the (Ca2+ + Mg2+)-ATPase represents the enzymatic basis of the high-affinity calcium pump. The calcium pump/enzyme system was inhibited by orthovanadate at comparatively high concentrations (calcium transport: K0.5 congruent to 100 microM; (Ca2+ + Mg2+)-ATPase: K0.5 greater than 100 microM). Upon Hill analysis, the tumor cell (Ca2+ + Mg2+)-ATPase failed to exhibit cooperative activation by calcium which is characteristic of the analogous enzyme in the plasma membrane of normal cells.
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PMID:A high-affinity, calmodulin-sensitive (Ca2+ + Mg2+)-ATPase and associated calcium-transport pump in the Ehrlich ascites tumor cell plasma membrane. 613 89

We studied the pleomorphic adenoma of the salivary gland ultrastructurally and cytochemically [Mg2+-activated adenosine triphosphatase (Mg2+-ATPase)], compared it with normal human fetal and adult salivary glands, and evaluated the histogenesis of this tumor. In the adult salivary gland, reaction products shows Mg2+-ATPase activity were localized in the plasma membranes of myoepithelial cells adjacent to the acinar cells or intercalated duct cells. However, in the salivary gland of the 16-week fetus, they were seen along all adjoining plasma membranes of the cells of terminal buds and duct-like structures. The present case of pleomorphic adenoma comprised two histological components: solid and myxomatous areas. Reaction products were seen along adjoining plasma membranes of both light and dark cells in solid areas.
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PMID:A cytochemical study on the salivary gland pleomorphic adenoma (mixed tumor) and the fetal and adult salivary gland. 614 24

PLC/PRF/5, a tissue culture cell line derived from a human hepatocellular carcinoma and producing hepatitis B surface antigen (HBsAg), was studied by immune and enzyme histochemical techniques. HBsAg was demonstrated in the cytoplasm and on the surface of tumor cells. The percentage of HBsAg-positive cells in subculture increased with time until almost all cells expressed HBsAg when the monolayer reached confluence. Similar patterns were found for alpha 1-anti-trypsin and carcino-embryonic antigen, whereas alpha-fetoprotein was observed only in small foci of cells. Hepatitis B core antigen and albumin were not detected. gamma-Glutamyl transferase activity was markedly increased in the tumor cells, whereas adenosine triphosphatase and glucose-6-phosphatase activities were not demonstrable. Patterns of antigenic expression and enzyme phenotype of PLC/PRF/5 cells show remarkable resemblance to those observed in vivo in human hepatocellular carcinoma. Therefore, this cell line may be a useful model to study the control and modulation of both oncofetal antigens and HBsAg.
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PMID:Immune and enzyme histochemical studies of a human hepatocellular carcinoma cell line producing hepatitis B surface antigen. 616 57


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