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

The mechanism of action of the cytotoxic protein P6 isolated from cobra venom (Naja naja) which shows preferential cytotoxicity particularly to Yoshida sarcoma cells has been studied by its effects on the membrane-bound enzyme (Na-++K-+)-ATPase (ATP phosphohydrolase, EC 3.6.1.3) of a variety of cell systems. Evidence obtained with Yoshida sarcoma cells, dog and human erythrocytes and three tissue culture cell lines KB (human oral carcinoma), Hela (human cervix carcinoma) and L-132 (human lung embryonic) shows that inhibition of (Na-++K-+)-ATPase by the P6 protein can be correlated with its lytic activity. (Na-++k-+)-ATPase of Yoshida sarcoma membrane fragments inactivated by P6 protein could be reconstituted by the addition of phosphatidylserine and phosphatidic acid. It is conceivable that lysis of cells by the P6 protein may be due to an imbalance of K-+ and Na-+ in the cell which leads to swelling and disintegration of the membrane structure. Observations indicate that the P6 protein combines with membrane constituents of susceptible cells. The overall evidence suggests that both the specificity of its protein structure and the highly basic nature of the P6 protein are factors which enable it to compete with the lipid moiety maintaining the (Na-++k-+)-ATPase of the susceptible cells in proper conformation for activity.
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PMID:Inactivation of (Na-++K-+)-stimulated ATPase by a cytotoxic protein from cobra venom in relation to its lytic effects on cells. 12 1

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

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

The induction of concomitant immunity was studied in Donryu strain rats with Yoshida ascites sarcoma cells. The changes of enzyme activity in spleen lymphocytes were also examined in normal and tumor-bearing rats. The concomitant immunity was detected 1 week after transplantation of tumor cells. Extended metastases were found 2 weeks after transplantation. The enzyme activities of ATPase and acid phosphatase were definitely higher than that of normal rat 1 week after the transplantation but decreased to lower level than normal 2 weeks later. On the other hand, alkaline phosphatase activity increased 3 times at 1 week after the transplantation and remained at the same level even at 2 weeks later.
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PMID:Changes of enzyme activities in spleen lymphocytes from tumor-bearing rats. 17 Nov 91

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

The molecular mechanisms involved in the inactivation of (Na+ + K+)-stimulated ATPase of Yoshida sarcoma cells by a cytotoxic protein (P6) from cobra venom have been examined. The overall data obtained using purified (Na+ + K+)-stimulated ATPase of Yoshida sarcoma cells suggest that cytotoxin P6 combines with phosphatidyl serine and a glycolipid which are closely associated with (Na+ + K+)-stimulated ATPase which in turn may lead to the inactivation of the enzyme in this cell system.
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PMID:Inactivation of membrane-bound (Na+ +K+)-ATPase of Yoshida sarcoma cells and cobra venom cytotoxin complex with the glycolipid components of the enzyme system. 22 83

Inactivation of (Na+ + K+)-ATPase of Yoshida sarcoma cells and beef brain microsomes by phospholipase A2 and a cytotoxin P6 from snake venom has been examined in relation to their activity to degrade phospholipids. Cytotoxin P6 which was most basic and devoid of phospholipase activity was most effective in inhibiting the (Na+ + K+)-ATPase of Yoshida sarcoma cells. Phospholipase A2 from Naja naja which was most active in degrading phospholipids was least effective in inhibiting (Na+ + K+)-ATPase in Yoshida sarcoma cells or in beef brain microsomes. Addition of trace amounts of cytotoxin P6 to the phospholipase considerably enhanced the inactivation of (Na+ + K+)-ATPase. The evidence suggests that the charge of the inhibitor protein and its specific structure play an important role in the inactivation of (Na+ + K+)-ATPase.
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PMID:Influence of charge on the inactivation of membrane bound (Na+ + K+)-ATPase of Yoshida sarcoma cells by inhibitor proteins from cobra venom. 23 2

Limitless numbers of various genetic structures have been formed in chromosomes and plasmids and numerous bioactive compounds are produced by microorganisms. Therefore, it may be said that compounds useful in treatment of cancer will be found more and more in microbial secondary metabolites and more effective antitumor antibiotics and their derivatives, or more effective products producing immune resistance to cancer, will be discovered. In these studies, as discussed in this paper, the most urgent problem is to establish a rational screening principle or system to select compounds worth clinical examination. This is particularly important in the analog area. Bleomycin is an analog of phleomycin chosen because of lower renal toxicity. It has become an antitumor agent of significant value. Macromycin is a new structure which has been found to bind with animal cells and inhibit growth. Neothramycin is a new benzodiazepine antibiotic which has lower toxicity than other structures studied in this class and is active against L1210, Yoshida sarcoma, and Sarcoma 180. Aclacinomycin A is an analog of adriamycin chosen for clinical study based on its low cardiac toxicity and high distribution in mouse lung and spleen. Coriolins are another new structural class. Diketocoriolin B has activity in L1210 leukemia and has been shown to inhibit Na-K-ATPase. Bestatin is a compound which inhibits aminopeptidase B and leucine aminopeptidase has been shown to increase delayed hypersensitivity. Bestatin also increases the effects of other antitumor agents such as adriamycin, and bleomycin.
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PMID:New microbial secondary metabolites under preclinical development for cancer treatment. 70 7

A magnesium-independent deoxyuridine-5'-triphosphatase was found in Yoshida sarcoma cells but not in normal rat liver. The phosphatase is specific for deoxyuridine 5'-diphosphate and deoxyuridine triphosphate, and its Km for deoxyuridine triphosphate is 2.7 X 10(-7) M. The enzyme was not inhibited by fluoride and required no divalent cations. Thus it differs from known nucleotide phosphatases. Deoxyuridine monophosphokinase, which is detectable in a crude extract of normal rat liver, could not be detected in an extract of Yoshida sarcoma cells. However, with hydroxylapatite column chromatography of the extract, a deoxyuridine 5'-monophosphate kinase activity as high as that in normal rat liver was found in fractions separated from the phosphatase activity. Thus the absence of detectable deoxyuridine 5'-monophosphate kinase activity in the crude extract of Yoshida sarcoma cells is due to the presence of this nucleotide phosphatase.
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PMID:A new deoxyuridine-5'-triphosphatase in Yoshida sarcoma cells involved in deoxyuridine 5'-triphosphate metabolism. 85 39

A 54-year-old man was admitted because of right supraclavicular lymphadenopathy of some weeks duration. Computed axial tomography revealed a large multinodular lesion in a supraclavicular lymph node. The patient then had a supraclavicular lymph node biopsy. Light microscopy showed a tumor whose structure was suggestive of an interdigitating cell sarcoma. Enzyme and immunohistochemical analysis showed that the tumor cells possessed membranous adenosine triphosphatase activity, intracytoplasmic S100 protein, surface CD1a and CD4 antigens, and HLA-DR antigen. Ultrastructural examination showed that the cells exhibited many interdigitating cytoplasmic extensions, but no Birbeck granules. DNA content analysis of the tumor cells proved that the cells were malignant. These data are consistent with derivation from a lymph node interdigitating cell.
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PMID:Lymph node interdigitating cell sarcoma. A case report. 172 55


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