Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The fatty acid composition of plasma membrane derived from Ehrlich ascites tumor cells was altered in vivo by changing the dietary lipid of the tumor-bearing mice. The activity of (sodium + potassium)-adenosinetriphosphatase ((Na+ + K+ATPase), in partially purified plasma membranes, was measured ass a function of temperature. Arrhenius plots of the data were biphasic. Striking differences, dependent on the membrane fatty acid composition, were observed in the transition temperature and in the energies of activation below the transition temperature. The transition temperatures for the (Na+ + K+)-ATPase of plasma membrane derived from tumor cells grown in mice fed a regular chow diet containing a mixture of fatty acids (PMC), a 16% sunflower oil diet (PMSU), or a 4% tristearin diet (PMTS) were 20, 21, and 13.5 degrees C, respectively...
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PMID:Changes in (Na+ + K+)-ATPase activity of Ehrlich ascites tumor cells produced by alteration of membrane fatty acid composition. 12 55

Treatment of ascites tumor cells with dextran sulfate resulted in a marked inhibition of the incorporation of [14C]valine into protein in the presence of a high Na+ medium. Amino acid incorporation was restored after i.p. injection of these cells into mice or by exposure of the cells to ascites fluid in vitro. In a medium high in K+ and low in Na+, [14C]valine incorporation into protein took place in dextran treated cells. Rotenone inhibited the reaction, which could be restored by addition of both inorganic phosphate and either glucose or glucose 6-phosphate. Quercetin, an inhibitor of the Na+-K+-ATPase, markedly depressed the incorporation of [14C]valine into protein in intact sdviyrd tumor cells in a high Na+ medium. There was little or no inhibition of protein synthesis in dextran sulfate treated cells when tested in a high K+-low Na+ medium. These experiments suggest a relationship between protein synthesis and the operation of the membranous Na+-K+-ATPase.
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PMID:Protein synthesis in dextran sulfate-treated ascites tumor cells. 13 42

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

The way in which the lectins concanavalin A (Con A) and Ricinus communis agglutinin (Ricin) alter the K+ content of Ehrlich ascites tumor cells was investigated. Unidrectional and net fluxes were determined in unwashed cells during a time course following lectin addition. Total influx, ouabain sensitive influx, Mg++- and Na+-K+-ATPase activity were all unaffected. Cell ATP content was normal for at least 19 minutes after exposure to Con A. Early after contact with Ricin or Con A efflux was stimulated 2-3-fold, resulting in net K+ loss, but after 20 minutes efflux had returned to normal. Ricin and Con A acted similarly although Ricin was present at only 1/50 the concentration of Con A. When the findings are evaluated together with previous work it is suggested that a particular membrane glycoprotein may be concerned in the efflux alteration observed.
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PMID:Nature of lectin-induced alteration of potassium transfer in Ehrlich ascites tumor cells. 13 11

An electron-microscopic study of a choroid plexus papilloma from the lateral ventricle of a child revealed fine structural features typical of normal choroid plexus tissue. Utilizing the Ernst technique for demonstrating ouabain-sensitive, potassium-dependent phosphatase activity, Na-K-ATPase was localized along the basal and lateral plasmalemmas of the tumor epithelium but not along the ventricular surface (apical plasmalemma). This localization is similar to that found in normal choroid plexus epithelium of all species studied to date.
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PMID:Choroid plexus papilloma. II. Ultrastructure and ultracytochemical localization of Na-K-ATPase. 13 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

A rabbit antiserum to first-trimester human fetal tissue had greater reactivity in complement fixation and saturation binding assays with fetal tissues than with both a pool of normal adult lung, liver, and kidney and pools of the individual organs. This anti-fetal membrane reactivity was only partially inhibited by carcinoembryonic antigen. The serum still reacted strongly with human fetal and tumor cells after rendering it specific for plasma membrane components by adsorption to and elution from intact human fetal tissue culture cells. This plasma membrane-specific serum was then used to monitor the purification of the fetal membrane-associated antigens. The fetal antigens copurified with the putative plasma membrane enzymatic markers 5'-nucleotidase and Mg2+-adenosinetriphosphatase through differential and density gradient centrifugation. Insulin-binding activity only partially copurified with the antigenic activity. Little antigenic activity was found in nuclear and mitochondrial fractions. The isolation protocol gives fetal plasma membrane-associated antigens in approximately 50% yield with moderate purification. The sera and isolation procedures described should have general utility for the detection of human oncofetal antigens.
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PMID:Isolation and partial characterization of plasma membranes bearing human fetal-associated antigens. 14 4

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

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


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