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)

Embryonal rhabdomyosarcomas from the nasopharynx of two children were examined by histochemical methods commonly applied to muscle biopsies. These stains included nicotinamide adenine dinucleotide-tetrazolium reductase (NADH-TR), succinate dehydrogenase (SDH), PAS, PAS-diastase, myophosphorylase, calcium-mediated adenosine triphosphatase (ATPase) preincubated at high and low pH, and oil red O. Myofibrils were easily identified with ATPase and blood vessel walls were also stained. NADH-TR clearly showed longitudinal and cross-striations that were not seen with H&E or PTAH stains. The modified Gomori trichrome stain additionally contributed to the recognition of myofibrils. Some techniques of muscle histochemistry applied to fresh frozen sections of tumor tissue may provide evidence of muscular differentiation in otherwise poorly differentiated sarcomas for a more accurate diagnosis of rhabdomyosarcoma.
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PMID:Diagnostic value of histochemistry in embryonal rhabdomyosarcoma. 9 52

Membrane glycoproteins have been studied in the normal lactating mammary gland and R3230 AC mammary tumor of the rat. Plasma membrane-enriched fractions were obtained from these tissues by discontinuous sucrose gradient centrifugation of a microsomal preparation from the tissue homogenates. The lightest membrane fractions (F-1 and F-2) have the greatest enrichment of plasma membrane markers, with a 14- to 20-fold purification of 5'-nucleotidase and Na+-K+ -adenosine triphosphatase over the homogenate values in both tumor and normal tissues for F-1. Electron microscopy shows smooth membrane vesicles for these fractions. Polypeptide analysis by acrylamide gel electrophoresis shows essentially the same patterns for F-1 and F-2 and only relatively minor differences between membrane components of tumor and normal tissues. Glycoprotein analysis of the polyacrylamide gels by periodate-Schiff staining indicates more dramatic differences. Membrane Fraction F-1 from normal tissue contains two major glycoproteins, GP-II and GP-III, while Fractions F-2 and F-3 contain an additional glycoprotein, GP-I, with a higher apparent molecular weight. In the tumor, the component corresponding to GP-III is decreased or absent and a new component GP-IV is seen at a lower apparent molecular weight.
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PMID:Membrane glycoprotein differences between normal lactating mammary tissue and the R3230 AC mammary tumor. 12 79

A Mg2+- and Ca2+-stimulated adenosine triphosphatase (ATPase) at the outer surface of intact Ehrlich ascites tumor cells is described. A surface-bound adenosine triphosphate (ATP)-splitting activity at a lower rate was also demonstrated in the absence of Ca2+ but with Mg2+, Na+, and K+ present in the isotonic medium. Hence, when part of the Mg2+ was exchanged for Ca2+, a marked increase of the ATP-splitting activity was observed. The stimulatory effect of Ca2+ was seen only if both Na+ and K+ were present in the isotonic incubation medium. Thus, the enzyme activity was Mg2+- and Ca2+-dependent. Ca2+, together with the monovalent cations was inhibitory compared with Mg2+ under similar conditions. The apparent Km for ATP for the Mg2+-stimulated ATPase is 0.05 mM, while that of the Mg2+- and Ca2+-stimulated enzyme is 0.10 mM. The Vmax of the former is 0.8 mu-mole per 100 mg Schneider protein per 30 sec compared with 1.92 mu-moles per 100 mg Schneider protein per 30 sec for the latter. The calculated Km for the Mg2+- and Ca2+-stimulated ATPase after subtraction of the Mg2+-stimulated part is 0.22 mM. Ethacrynic acid and N-ethylmaleimide both inhibited the Mg2+- and Ca2+-stimulated ATPase by about 10 percent, while the ouabain inhibition was 15 percent. Cytochalasin B did not influence the enzyme activity, whereas La3+ had a slight stimulatory effect.
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PMID:A Mg2+- and Ca2+-stimulated adenosine triphosphatase at the outer surface of Ehrlich ascites tumor cells. 12 5

A cell line (HGC-27) was established by culture of the metastatic lymph node from a gastric cancer patient diagnosed histologically as undifferentiated carcinoma. HGC-27 cells were polygonal or short spindle-shaped and adhered to glass surfaces as a monolayer. The cells were probably derived from gastric cancer cells, as their origin from mesenchymal tissues can be excluded morphologically and enzyme-histochemically. Enzyme activities were generally negative or low, except for adenosine triphosphatase, lactic dehydrogenase and leucine aminopeptidase. These scanty findings might reflect the undifferentiated character of the original tumor cells. The cloning efficiency was 5.3% in liquid medium and 1.0% in soft agar. The doubling time was about 17 hr. Chromosomal analysis revealed a mode of 109 and 110 chromosomes.
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PMID:Human cell line (HGC-27) derived from the metastatic lymph node of gastric cancer. 13 73

The purpose of this study was to measure uptake of tritiated digoxin by neoplastic tissues known to have differential contents of sodium-potassium adenosine triphosphatase (Na + K + ATPase), the presumed receptor for digoxin. Tumor samples were removed at the time of craniotomy in seven patients with meningiomas (Group 1) and seven patients with more malignant central nervous system tumors (Group 2) (three astrocytomas, three glioblastomas, one meduloblastoma). Patients with meningiomas were found to have a significantly higher digoxin uptake (21.8 +/- 7.3 ng/gm tumor versus 5.7 +/- 5.2 ng/gm tumor; (p less than 0.01) and a significantly greater tissue/serum ratio (13.9 +/- 11.7 versus 3.26 +/- 3.7, p less than 0.0). This study provides the first demonstration of increased uptake of digoxin by noncardiac pathologic tissues. The results are most likely due to differences in the number of digoxin receptor sites.
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PMID:Differential uptake of tritiated digoxin in benign and malignant central nervous system neoplasms. 13 73

Cells of sarcoma 180 and of Ehrlich's carcinoma were maintained by serial transplantation in male and female Swiss mice. Either estrogen, progesterone, or testosterone were injected im at doses of 1 mg/mouse. Ascitic fluid was aspirated at intervals of 1, 3, 6, 24, and 48 hours following hormone injections. Enzyme activities were analyzed by subjective grading according to the intensity of staining reaction. Estrogen produced enhancement of alkaline phosphatase activity in both types of cells in both sexes of mice. Progesterone produced increased alkaline phosphatase activity in both types of cells from female hosts but an inhibitory effect in male hosts' cells. Testosterone produced no change in enzyme activity in tumor cells of female hosts but in male hosts it inhibited enzyme activity of sarcoma 180 cells and activated activity in carcinoma cells. The effect of all 3 hormones on acid phosphatase activity was activation. With adenosine triphosphatase, estrogen stimulated the activity in both types of tumor in both sexes. Progesterone stimulated cells from male hosts with little or no effect on cells from female hosts. This enzyme was resistant to testosterone. Succinate dehydrogenase activity under similar conditions was different. Estrogen reduced this activity and progesterone produced some inhibition of activity. Testosterone inhibited the sarcoma cells but had no effect on carcinoma cells of either sex. Others have shown that sex hormones affect the enzyme activities beyond the target tissues, particularly in the liver, kidney, and pancreas. Different responses of the enzymes seemed to depend on the endogenous hormonal status of the mice.
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PMID:Enzymatic responses of transplanted tumour cells towards estrogen, progesterone and testosterone. 13 8

To our knowledge, there are currently no reports in the literature that discuss the fine structure of the striated ducts of the human parotid gland. Papillary cystadenoma lymphomatosum (Warthin's tumor) is a benigh neoplasm found almost exclusively in the parotid gland that represents about 16% of all neoplasms of the gland. This neoplasm is believed to arise from the striated and/or excretory ducts, but there are contradictions with regard to the proposed origin and the cellular composition of some Warthin's tumors. Tissue was obtained at the time of surgery and examined ultrastructurally and cytochemically for the localization of alkaline phosphatase and adenosine triphosphatase. Myoepithelial cells were found ultrastructurally and cytochemically on the proximal aspect of the striated duct, with their cell bodies situated at the junction of the striated and intercalated ducts. Two Warthin's tumors were observed with cells that were structurally and cytochemically similar to myoepithelial cells.
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PMID:Ultrastructure of the parotid duct. Cytochemical studies of the striated duct and papillary cystadenoma lymphomatosum of the human parotid gland. 14 20

Seven well differentiated chondrosarcomas of bone have been analyzed by electron microscopy, and the fine structural localization of adenosine triphosphatase and nonspecific alkaline phosphatase has been elucidated. On the basis of the fine structural appearance, two distinct cell types were shown to constitute the tumor tissue: chondrocyte-like cells and large "mitochondria-rich cells". Large, multinucleated cells in the tumor did not seem to correspond to osteoclasts but rather were likely to represent true neoplastic cells. Some chondrocyte-like cells appeared to be binucleated by virtue of deep, groove-like nuclear indentations. Adenosine triphosphatase and alkaline phosphatase were associated with the plasma membrane of both chondrocyte-like and mitochondria-rich cells suggesting that they might be of common origin. Normal chondroblasts and chondrocytes lack histochemically demonstrable adenosine triphosphatase on their plasma membrane. Presence of this enzyme in the tumor cells may indicate that they are histogenetically related to immature non-chondroid matrix forming cells (known to carry the enzymes).
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PMID:Contribution to the knowledge of the fine structure of chondrosarcoma of bone. With a note on the localization of alkaline phosphatase and "ATPase". 15 79

The formation of cellular aggregates (foci) in CV-1 cells following infection with Yaba tumor poxvirus is dependent upon cell passage level, temperatue of incubation, and calcium concentration in the medium. Resistance of older cells can be reversed by maintaining calcium at 0.1 mM or by adding cortisone acetate (1 mug/ml), hydrocortisone, or estradiol-17beta to the cultures. In susceptible cells, foci formation was inhibited slightly by methyltestosterone and inhibited completely by dexamethasone, aldosterone and progesterone. Activities and patterns of enzymes associated with cytoplasmic membranes (alkaline phosphatase, mononucleotidase, and Na+-K+-adenosine triphosphatase) and lysosomes (beta-glucuronidase and acid phosphatase) of the younger susceptible and the older resistant CV-1 cells differed. These differences apparently occurred in concert with phenotypic changes in the membranes that reduced the mobility of older resistant cells. In susceptible culture, unifected cells migrated to the infected cell and participated in foci formation. Reduction of the calcium content to 0.1 mM apparently removed some of the constraints on mobility of the resistant cells. Although the hormones may have had a similar effect, the changes in enzyme patterns indicated basic alterations in protein synthesis. The development of resistance to foci formation occurred between the 45th and 50th passage level. Hormonal reversal of this resistance resulted in enzyme profiles that reflected the pattern of young susceptible cells.
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PMID:Alterations of enzymes associated with plasma membranes and cellular organelles during infection of CV-1 cells with Yaba tumor poxvirus. 16 62

Mitochondria from a rat mammary tumor (R3230AC) have been compared with mitochondria from pregnant and lactating rat mammary glands, with particular attention paid to inner membrane enzymes and Transport proteins. In the tumor the mitochondrial adenosine triphosphatase was not activated by 2,4-dinitrophenol, in contrast to the mammary mitochondria from lactating or pregnant rats. Translocation of adenosine diphosphate across the inner membrane was found to be more rapid in the tumor by virtue of lovered Km adenosine diphosphate and raised Vmax. Transport of phosphate and dicarboxylic acids occurred at similar rates in all three types of mitochondria. The inner membrane proteins were also examined directly by sodium dodecyl sulfate/polyacrylamide gel electrophoresis and some differences are noted. These results, although they indicate subtle differences between the inner mitochondrial membranes of tumor as compared with those of pregnant or lactating rat mammary glands, cannot form the basis of an explanation for enhanced glucose utilization and aerobic lactic acid production in this tumor.
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PMID:A comparative study of inner membrane enzymes and transport systems in mitochondria from R3230AC mammary tumor and normal rat mammary gland. 16 45


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