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)

Adenosine triphosphatase enzymatic activity was investigated in human approximatively normal, dysplastic and neoplastic mammary tissue, by three different methods. Staining intensity varied within wide limits; myoepithelial cells and blood vessels showed similar enzymatic activity. Epithelial cells reacted only faintly, or not at all; carcinoma cells were never labelled. Stromal response was highly variable. The calcium-cobalt method of Padykula and Herman gave more intense reactions than the lead-nitrate procedure of Wachstein and Meisel, either in the original form or according to the modifications recommended by Russo and Wells. With the latter method the sharpness of stain deposits on the different structures was markedly enhanced. The functional significance of ATPase activity is discussed.
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PMID:ATPase activity in the breast: a comparison between three methods. 9 Dec 95

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

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

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

This time trend of hemodynamics and mitochondrial functions were studied to determine whether the ligation of the hepatic artery would result in an antitumor effect on 3'-methyl-4-dimethylaminoazobenzene-induced hepatic carcinoma in rats. The studies revealed that the hepatic tumors were nourished predominantly by the artery and less by the portal vein; the size of the vascular beds in the hepatic tumors decreased as compared with those in the non-tumor area; and as the tumors grew larger, the artery became less predominant and the size of vascular beds decreased further. The mitochondria in the tumor were characterized by impaired growth, impaired oxidative phosphorylation, and by the low activity and nucleotide specificity of membrane bound ATPase. Hepatic dearterialization enhanced ischemia in the tumors and was accompanied by intensified impairment of the aerobic energy production, resulting in necrosis of the tumor. The effects of the dearterialization tended to decrease after the 5th day following the operation. In view of the gross findings upon relaparotomy and the recovery of hemodynamics and mitochondrial functions, this tendency appeared to be chiefly attributed to the increasing collateral circulation.
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PMID:Hepatic dearterialization in 3'-methyl-4-dimethylaminoazo-benzene-induced hepatocellular carcinoma with special reference to circulatory dynamics and mitochondrial functions. 16 34

The histochemical reaction for adenosine triphosphatase (ATPase) has previously been used to differentiate myoepithelial from epithelial cells in the breast and to investigate the possible contribution of myoepithelial cells to mammary carcinoma. Discrepancies in published reports prompted this study of ATPase in non-neoplastic breast and infiltrating ductal carcinoma. ATPase was localized mainly on myoepithelial cells of normal breast and was identified with significant frequency on epithelial cells in hyperplastic ducts. Infiltrating ductal carcinomas usually displayed a variable reactivity. In one instance, malignant cells demonstrating mucin production were found to be ATPase-positive. An infiltrating ductal carcinoma of the papillary type with apocrine features was also strongly ATPase-reactive. It is concluded that ATPase is not an exclusive marker of myoepithelial cells and, therefore, data resulting from the use of this enzyme to study the role of the myoepithelium in mammary carcinoma must be interpreted with caution.
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PMID:Distribution of adenosine triphosphatase in infiltrating ductal carcinoma and non-neoplastic breast. 18 14

Different adenosine triphosphatase (ATPase) activities were detected at an ultrastructural level in order to differentiate epithelial and myoepithelial cells in normal and neoplastic mouse mammary tissues. Mg2+ dependent and Na+-K+-dependent ATPase activities were studied in: BALB/c mouse mammary gland; a BALB/c carcinoma from a transplantable D2 hyperplastic nodule; a stable cell line, MCF-8, derived from the BALB/c carcinoma; and a BALB/c scirrhous-like carcinoma induced by MCF-8 cell inoculation. Mg2+-dependent ATPase was detected in the plasma membranes of the normal mouse mammary epithelial cells, the epithelial component of the BALB/c carcinoma, the MCF-8 cells in culture, and the atypical epithelial component of the scirrhous-like carcinoma. Na+-K+-dependent and Mg2+-dependent ATPase were localized in the plasma membranes of the myoepithelial cells of the normal mammary gland and the BALB/c carcinoma. The results from these histochemical studies established that the cell of origin in both the BALB/c carcinoma and the scirrhous-like carcinoma was the mammary epithelial rather than the myoepithelial cells. Furthermore, these results indicated that the MCF-8 cell line was derived from the epithelial component of the primary BALB/c carcinoma. These conclusions, which were based on histochemical study, were supported by the presence of intracisternal type A viral particles in the epithelial cells of the primary BALB/c carcinoma, the MCF-8 cells in culture, and the epithelial cells of the scirrhous-like carcinoma. Thus, the enzymatic markers were specific for cell type and remained unchanged by the process of cell transformation.
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PMID:Adenosine triphosphatases as histochemical markers for the cell of origin in experimental mammary carcinoma. 19 Nov 76

The influence of estrogen, progesterone and testosterone on the activities of alkaline and acid phosphatases, adenosine triphosphatase and succinate dehydrogenase were determined by cytochemical methods in sarcoma 180 and Ehrlich's carcinoma cells transplanted in male and female Swiss mice. The results revealed differential effects of the sex hormones on different enzymes which seemed to depend on the type of tumour cell studied and the sex of the host mice.
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PMID:Enzymatic responses of transplanted tumour cells towards estrogen, progesterone and testosterone. 92 17

Hydrolysis of extracellular ATP and other nucleoside phosphates by A-431 human epidermoidal carcinoma cells was studied. The hydrolysis of extracellular ATP by these cells required either Mg2+ or Ca2+, and either cation could be replaced by Co2+, Fe2+, or Mn2+. Nucleoside triphosphates (ATP, GTP, CTP, UTP, and dTTP), but not nucleoside diphosphates, were hydrolyzed by the cells with Km and Vmax values similar to those for ATP (0.9-1.1 mmol/l and 6-10 nmol Pi formed/10(6) cells, respectively). The hydrolysis of ATP was inhibited strongly by ATP-gamma S and AMPPNP, and weakly by AMPCPP and ADP-beta S, but not by AMPCPP or AMPCP. Since the hydrolysis of [gamma-32P]ATP was inhibited by all these nucleoside triphosphates, the binding site for ATP is presumed to be the same as that for the other nucleoside triphosphates. All these results indicate that ecto-ATPase activity associated with A-431 cells is due to ecto-nucleoside triphosphatase. The nucleotide specificity shown in the present study indicates that ecto-nucleoside triphosphatase associated with A-431 cells is a molecule different from P2-purinergic receptors which can be stimulated specifically with nucleoside phosphates like ATP, ADP, UTP, UDP, and GTP, but not by other nucleotides.
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PMID:Characterization of ecto-nucleoside triphosphatase on A-431 human epidermoidal carcinoma cells. 129 31

Type 18 human papillomavirus (HPV18) is a genital virus closely associated with cervical carcinoma. To analyze the transcriptional activities of the long control region (LCR) of the HPV18 genome, we have produced 12 transgenic mice harboring the HPV18/LCR sequence fused to a promoterless SV40 T-antigen (TAg) gene. The mice were small in body size, generally very weak, and none lived longer than 110 days. Three mice with the longest life span (58-110 days) developed hyperplastic thymus and/or lymph node and were further analyzed. In these mice, Northern hybridization failed to detect TAg transcripts in any of the 25 organs studied. However, spliced TAg RNA was detected by polymerase chain reaction in the hyperplastic thymus and lymph node and in the normal submaxillary gland, stomach, large intestine, urinary bladder, and the cerebrum, indicating the presence of very low cellular levels of TAg RNA in these organs. When immunostaining was performed on the hyperplastic thymus, TAg protein was detected only in the ductal epithelial cells. Our results appear to indicate that the HPV18/LCR sequence was able to express only unregulated and basal levels of transcriptional activity in transgenic mice. Such a mode of transcription has become a major hindrance in the use of transgenic mouse system for the studies of the biology of the human papillomavirus.
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PMID:Unregulated and basal transcriptional activities of the regulatory sequence of the type 18 human papillomavirus genome in transgenic mice. 131 63


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