Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.6.1.3 (ATPase)
 65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A permanent cell line (HLC-1) was established from the pleural effusion of a human lung adenocarcinoma. The cell line was characterized by the monolayered and multilayered organoid growth of epithelioid cells with the doubleing time of about 33 hr and the modal chromosome number of 68. Cloning efficiency was 17.9% in liquid medium and 8.3% in soft agar. The cell produced a large amount of epithelial mucin. Electron microscopic examination revealed many secretory granules and terminal bars. They formed spherical aggregates in a gyratory culture which showed adenocarcinoma-like tubular structures histologically. Enzyme-histolochemically, they showed the characteristics of lung adenocarcinoma cells except for a few enzymes such as glucose-6-phosphatase and ATPase. Heterotransplantation of the cells produced the tumor. These characteristics confirm that HLC-1 cell line is a human lung adenocarcinoma cell line.
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PMID:Establishment and characteristics of a human lung adenocarcinoma cell line. 14 93

Plasma membrane fractions from normal colon cells and a transplantable colon adenocarcinoma were isolated and purified by differential and zonal density centrifugation. Enrichment of normal and adenocarcinoma plasma membranes was found in zonal fractions I and II (ZI and ZII) following centrifugation in an 18--50% sucrose gradient. The distribution of various marker enzymes in normal colon preparations suggested an apical origin for the membranes obtained in zonal fraction I while zonal fraction II appeared to contain basal-lateral membrane fragments. Enzymatic analysis of the plasma membrane derived from the colon tumor indicated that these fractions possess a more uniform distribution of Na-K+ ATPase perhaps reflecting a dedifferentiated state. The plasma membrane fractions isolated should prove useful for investigation of transport and other properties of vesicles derived from malignant and normal colon cells.
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PMID:Isolation and purification of normal and malignant colonic plasma membranes. 14 56

Electron-histochemical study of phosphohydrolases (ATPase, acid and alkaline phosphatases) in cells of the normal gastric mucosa, duodenal mucosa and gastric adenocarcinoma of man was carried out. In cancer cells retaining to a certain extent the ultrastructural features of the chief cells, parietal cells of enterocytes, the distribution of the product of reaction for ATPase and acid phosphatase in nucleoli, endoplasmic reticulum membranes, intracellular cannaliculi, plasmalemma, mitochondria, the distribution of the product of reaction for ATPase and acid phosphatase in nucleoli, tural features of enterocytes, no activity of alkaline phosphatase could be demonstrated in membranes of the villi of the striated border. Alongside with the retention or disappearance of electron-histochemical features, some of them may be enhanced. Thus, the activity of acid phosphatase was increased in lysosomes of cancer cells (of the type of chief cells). So, in cancer cells of adenocarcinoma the structure-functional rearrangement going in different directions is observed in addition to the process of simplification and unification.
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PMID:[Electron-microscopic histochemistry of phosphohydrolases in the normal mucosa and in the cells of human gastric adenocarcinoma]. 14 57

The oxidative phosphorylation and ATPase activity (initial and stimulated by DNP and Mg2+) in tumor mitochondria were investigated. The intact mitochondria of Zajdela hepatoma, in contrast to liver mitochondria, exhibit the ATPase activity which is slightly stimulated by 2,4-dinitrophenol and is markedly activated by Mg2+. The mitochondria from transplantable solid tumors (adenocarcinoma 755, Iensen sarcoma, sarcoma 45) despite satisfactory morphological integrity under electron microscopy are biochemically less intact than the mitochondria of hepatoma. ATPase of these mitochondria is also slightly stimulated by 2,4-dinitrophenol and significantly by Mg2+. The ATPase activity of thymus mitochondria, the normal tissue with sufficiently high proliferative activity, corresponds to that of tumor mitochondria. The total amount of enzyme in mitochondria of tumors investigated and thymus is not lowered, since the ATPase activity in the presence of both DNP and Mg2+ corresponds to the ATPase activity of liver mitochondria. The Mg2+ ATPase activity of tumor mitochondria is not sensitive or is only partly sensitive to oligomycin. The data obtained are indicative of a high lability of the phosphorylating system in tumor and thymus mitochondria. A possibility of reorganization of the energy mechanism of tumor mitochondria and some normal tissues in connection with increased metabolism requiring high energy consumption, is discussed.
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PMID:[Some peculiarities of ATPase in tumor mitochondria]. 15 49

Sarcomas were induced in CFW mice by the iv inoculation of simian virus 40 (SV40) in neonatal animals. Infection with murine malaria parasites, Plasmodium berghei yoelli, decreased the latency and increased the incidence and invasiveness of the tumors. All mice given both SV40 and P. berghei yoelli had sarcomas of the liver and spleen at 9 months of age. At 11 months of age, 70% of the SV40-inoculated mice had sarcomas of the liver indistinguishable from those in the group given both pathogens. Only 1 lung metastasis was seen in the SV40-treated group. The sarcomas contained SV40 T-antigen as revealed by the indirect immunofluorescence technique. Among adult CFW mice given iv injections of SV40, only 2 tumors were found at 11 or 12 months after virus inoculation. Both tumors were in the lungs; 1 was an adenoma and 1 was a papillary adenocarcinoma. Neither gave a positive reaction with the immunofluorescence test.
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PMID:Sarcomas induced by injection of simian virus 40 into neonatal CFW mice. 22 3

Although there is extensive data available on Ca2+ effects in normal tissues, comparatively little is known about its effects or regulation in tumor cells. The present studies were undertaken to investigate whether various extracellular calcium concentrations could modulate the expression of the tumor-associated antigen (TAA) recognized by monoclonal antibody (MAb) 44-3A6. It is highly expressed by the human lung adenocarcinoma cell line A549 and has been shown to be a 40-kD integral plasma membrane protein. Treatment of the A549 cell line with various concentrations of exogenous calcium showed a dose-dependent rise in the internal free calcium levels up to 2.4-2.9 mM (external calcium treatment). At higher concentrations, the internal calcium level showed a decline, indicating a higher calcium efflux. The calmodulin-dependent Ca(2+)-ATPase enzyme involved in calcium homeostasis was assayed under these same conditions. The enzyme activity increased with increasing external calcium concentrations showing a 5-fold increase in cells treated with 4.05 mM calcium. These data suggest that as the internal calcium approaches toxic levels, the Ca(2+)-regulated ATPase activity increases to reduce the calcium overload within the cell. Employing Western blot analysis and immunoperoxidase staining studies, this report shows that the antigen recognized by MAb 44-3A5 on A549 cells increased with an increase in calcium concentration. Evidence that this antigen is phosphorylated is presented using Western blot analysis of a radiolabeled antigen-enriched plasma membrane fraction. The previously reported subcellular localization, and now the phosphorylation and responsiveness to calcium by this TAA, gives it the properties predicted to be seen in a calcium 'pump-like' molecule. Thus, these studies support the hypothesis that this TAA may be important in intracellular calcium concentration control or that it is regulated via some calcium-mediated process.
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PMID:Changes in the expression of the tumor-associated antigen recognized by monoclonal antibody 44-3A6 in A549 cells due to calcium. 138 56

The expression and cytochemical localization of alkaline phosphatase and Na+-pump sites were investigated in the human adenocarcinoma cell line HT-29.18 during differentiation. In the undifferentiated state, HT-29.18 cells expressed ATPase activity on plasma membrane whereas they displayed no alkaline phosphatase activity. In differentiated HT-29.18 cells, strong alkaline phosphatase activity was present on the apical membrane, whereas ATPase activity was restricted to the basolateral membrane. Intra- and intercellular lumina (cysts) observed in undifferentiated cells were devoid of both enzyme activities. In differentiated cells, cysts bearing well developed microvilli were strongly positive for alkaline phosphatase activity, while this activity seemed to be lacking in cysts without microvilli. ATPase activity was not found in either type of structure. Finally, HT-29.18 differentiated cells expressed, at pH 9.0, a p-nitrophenylphosphatase activity six-fold greater than that of undifferentiated cells.
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PMID:Differential expression of alkaline phosphatase and ATPase activities in human colon carcinoma cell line HT-29.18 during differentiation. 296 Apr 4

Intact viable 13762 mammary-adenocarcinoma ascites cells hydrolyse added ATP. The localization of hydrolysis product and inactivation by the slowly penetrating chemical reagent diazotized sulphanilic acid indicate that this ATPase is at the external surface of the cell. A number of features differentiate this enzyme from mitochondrial, myosin and cation-transport ATPases. It is stimulated by either Ca2+ or Mg2+ and has little or no activity in their absence. It is insensitive to ouabain, oligomycin and azide. It is the major ATPase activity found in homogenates of gently disrupted 13762 cels. The ATPase activity is inhibited at high substrate concentrations and shows an apparent stimulation by concanavalin A in isolated membranes, but not in intact cells. The stimulation by concanavalin A results predominantly from a release from substrate inhibition.
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PMID:Ecto-enzymes of mammary gland and its tumours. Ca2+- or Mg2+-stimulated adenosine triphosphatase and its perturbation by concanavalin A. 625 85

Though the mechanism of 201Tl accumulation in thyroid tumours is not known yet, there are some hypotheses. In order to study the mechanism, potassium contents and Na, K-ATPase, of various organs of rats and human thyroid glands were analyzed . The conclusion through these experiments is as follows, 1 as the potassium contents and Na, K-ATPase activity of thyroid glands are not obviously higher than those of other organs, the 201Tl accumulation in thyroid is thought to be not owing to the similarity to the potassium ion, 2 pointing out high activity of Na, K-ATPase in heart and kidney, the accumulation mechanism of 201Tl in these organs has high relation to this activity, 3 though there is a tendency to have higher potassium contents among thyroid tumours, the difference in potassium contents between their histopathology is small; so that the tumour specificity is not explained from the potassium contents, and 4 as for Na, K-ATPase activity of thyroid tumours, papillary adenocarcinoma and follicular adenoma, which take more in 201Tl, have tendency to show higher activity; adenomatous goitre, which take less in 201Tl, has tendency to show lower activity. We suggested that the factor relating to the accumulation mechanism of 201Tl may be multiple, and Na, K-ATPase plays an important role in 201Tl specific uptake in thyroid tumours.
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PMID:[Accumulation mechanism of 201Tl--K-contents and Na, K-ATPase activities of tissues]. 632 87

Treatment of a variety of human tumor cells in monolayer cultures with low levels (40 to 80 microM) of adenosine 5'-diphosphate (ADP) or adenosine 5'-triphosphate (ATP) was recently shown to produce arrest of cellular growth in the S phase of the cell cycle (E. Rapaport, J. Cell. Physiol., 114: 279-283, 1983). We now demonstrate that exposure of two well-characterized colonic adenocarcinoma (HT-29 and SW-620) and two pancreatic adenocarcinoma (CAPAN-1 and PANC-1) cell lines in soft-agar cultures to exogenously supplied 5 to 20 microM ATP results in substantial inhibition of cellular growth. Exposure of the cells to 5 to 20 microM ADP produces slightly smaller growth-inhibitory effects, while 20 microM adenosine 5'-monophosphate or adenosine have marginal effects on cellular proliferation in these systems. Successful demonstration of these effects requires the use of heat-inactivated fetal bovine serum, since normal fetal bovine serum possesses enzymatic activities which catalyze the rapid degradation of adenine nucleotides. Tumor cell growth was assayed by the well-established colony formation assay as well as by [3H]thymidine incorporation into acid-insoluble material. [3H]Thymidine incorporation is performed 4 to 14 days after plating and correlates well with results obtained by colony formation assays. Due to the ectoenzymatic activities of the cells which include adenosinetriphosphatase and adenosinediphosphatase catalyzing the dephosphorylation of ATP and ADP, the effective levels of ATP that inhibit the growth of human tumor cells in this system, which is widely claimed to predict the in vivo response of a tumor, are lower than the 5 to 20 microM which are exogenously supplied. The two previously characterized, well-differentiated pancreatic and colonic tumor cell lines (CAPAN-1 and HT-29) were shown to exhibit higher chemosensitivity towards treatment with ATP and ADP than did the lesser-differentiated pancreatic and colonic tumor cell lines (PANC-1 and SW-620).
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PMID:Growth inhibition of human tumor cells in soft-agar cultures by treatment with low levels of adenosine 5'-triphosphate. 687 73


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