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 intracellular concentrations of the adenine nucleotides were determined in suspension cultures of WRL-10A cells, a subline of the L-929 mouse fibroblasts, during the progression of the cells from exponential growth to high-density, nonproliferating populations. The development of the nonproliferating state was associated with a 50% reduction of the adenine nucleotide pool, whereas the energy charge remained at values above 0.90. This change was also observed in the early phase of starvation of low-density cultures and could be reproduced by selective simultaneous withdrawal of glucose and glutamine, which indicated interference with the de novo synthesis of purines. In this respect, therefore, nonproliferating populations of WRL-10A cells resemble purine-limited bacterial systems but not density-inhibited normal fibroblasts in which the size of the adenine nucleotide pool is known to remain unchanged. This difference in the physiologic state of nonproliferating normal and neoplastic cells is potentially significant for tumor chemotherapy.
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PMID:Nonproliferating neoplastic cells in culture: behavior of the adenine nucleotides. 28 95

A study was made of the action of glucose or sodium succinate on subpopulations of the Ehrlich-I.Ch.Ph. ascite strain characterised by markers "A1" and "A", resp. After i.p. injection of glucose the amount of "A1"-cell reached 50 and almost 100% on the 5th and 7th day of tumor growth. After the transplantation of "A1"-cells into intact animals, a homogenous cytogenetic feature of subpopulation persisted during 2 passages only. Kinetics studies of a subvariance of the Ehrlich-I.Ch.Ph. tumor containing "A1"-cells show that the tumor growth rate and grade of malignancy slightly differ from those seen in the controls.
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PMID:[Polymorphism of a tumor cell population and selective processes. III. A change in the correlation of tumor cell subpopulations of the ascitic strain of Ehrlich-I.Ch.Ph. under the influence of glucose and sodium succinate]. 29 Dec 23

We have found that phagocytic leukocytes exposed to the tumor-promoting agent, 12-O-tetradecanoyl phorbol-13-acetate, efficiently release carbon-1 of 2-deoxyglucose in the form of CO2 with concurrent intracellular accumulation of a phosphorylated 5-carbon intermediate. In the absence of 12-O-tetradecanoyl phorbol-13-acetate, these cells release barely detectable amounts of CO2 from 2-deoxyglucose. 12-O-Tetradecanoyl phorbol-13-acetate, at a concentration of 1 ng/ml, has an immediate effect on CO2 release, which is temperature-dependent and linear with time and cell number. The ability of a number of phorbol ester-like compounds to enhance this catabolic pathway for 2-deoxyglucose correlates with their ability to act as tumor promotors and inflammatory agents. Although this effect of phorbol esters appears to be restricted to granulocytes, monocytes, and macrophages, the possibility arises that other mammalian cells are capable of catabolizing or can be induced to catabolize-2-deoxyglucose. Thus, 2-deoxyglucose decarboxylation should be considered whenever this analog of mannose and glucose is used as an indicator for sugar transport, especially when pharmacodynamic agents are present.
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PMID:Catabolism of 2-deoxyglucose by phagocytic leukocytes in the presence of 12-O-tetradecanoyl phorbol-13-acetate. 31 Jan 20

Amygdalin at various concentrations and with numerous impurities is the most common cyanogenic glycoside found in laetrile samples. Its chemical properties were first described in 1837, and pharmacologic studies have shown that ultimately it is broken down to HCN, benzaldehyde, and glucose by enzymes found in gut bacteria but not intracellularly in humans. Fatal and nonfatal toxicities to orally ingested cyanogenic glycosides have been reported worldwide. We review here the signs and symptoms of acute cyanide toxicity and its treatment. Substantial in-vitro and in-vivo testing in animal tumor systems has shown that amygdalin is entirely devoid of significant anticancer activity. Control animals often have lived longer than those treated with various doses and schedules of amygdalin. Acceptable clinical studies in humans are lacking, but such ventures would appear to be contraindicated from animal studies and observed human toxicities. We also discuss current legal-judicial aspects of laetrile therapy for cancer.
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PMID:The current status of laetrile. 35 91

The influence of population density in the progression from the nonneoplastic to the neoplastic state has been reassessed. Two twice-cloned, nonneoplastic mouse lines, NCTC 7914 and 7915, were transferred each 3 to 4 days at inoculum sizes selected to minimize or maximize cell-cell contact, 1 X 10(5) or 4 X 10(5) cells/T-15, respectively. As tested by in vivo assay, the regime designed to minimize cell-cell contact did not reproducibly delay transformation, and tumor production was observed in all lines, irrespective of inoculum size. Also, results of tumorigenesis assays correlated with blind evaluation of morphological and cytological alterations, growth in agarose, and susceptibility to killing by activated macrophages. Generally higher saturation densities were seen as a function of period in culture, and no significant differences in glucose utilization or lactic acid production were observed between nonneoplastic and neoplastic cell populations.
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PMID:Population density as a factor in the evolution of neoplastic cell lines. 35 29

To study the effect of E. Coli L-asparaginase on glucose tolerance and insulin release, 6 patients with neoplastic disease were subjected to 3 hour oral glucose tolerance tests with simultaneous measurement of serum immunoreactive insulin (IRI) levels before and following the intravenous administration of 5000 I. U. L-asparaginase/day for 4 days. Five of the patients exhibited a significant deterioration in glucose tolerance; however, no change was noted in their fasting glucose and IRI levels. The deterioration in glucose tolerance was associated with a decrease in the amount of insulin secreted in the first 30 minutes after the oral glucose load. The total amount of insulin released during the 3 hour test remained unchanged. These studies suggest that L-asparaginase can cause a deterioration of glucose tolerance without accompanying fasting hyperglycaemia. This may be due, in part, to a decrease in glucose-induced insulin release during the first thirty minutes following oral glucose.
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PMID:The effect of E. coli L-asparaginase on oral glucose tolerance and insulin release in man. 35 90

The release of glucagon from pancreatic and extrapancreatic sources was studied in normal rats and in rats carrying transplants of a MtT-W-15 tumor which secretes large quantities of growth hormone and prolactin. The tumor-bearing rats had high serum levels of A cell immunoreactive glucagon (IRGa), total immunoreactive glucagon (IRGT) and immunoreactive insulin (IRI) and an increased total glucagon and insulin content of the pancreas. Pancreatic islets isolated from tumor-bearing rats secreted more glucagon under basal conditions but did not respond significantly to low glucose stimulation. However, they contained more insulin per islet and secreted more insulin under basal and stimulated conditions. The serum IRGa response to arginine infusion in vivo was lower in the tumor-bearing than in the normal rats. The introduction of a 5% glucose solution into the small intestine caused similar increases in the level of serum IRGT in the two groups of rats. Thus, the tumor increased the total pancreatic glucagon content and basal secretion, blunted the A cell response to stimulation, but did not significantly alter the secretion of glucagon by the intestine. We attribute these responses to tumor-induced hypersomatotropinism although we cannot rule out an effect of the large amounts of circulating prolactin.
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PMID:Glucagon secretion in rats bearing a growth hormone producing tumor (MtT-W-15). 36 50

Phorbol myristate acetate (PMA), a tumor-promoter capable of influencing biologic functions of many cell systems, has been demonstrated to augment glucose-initiated insulin release from isolated rat islets of Langerhans. PMA caused a 2-fold increase in insulin release. This effect of PMA did not alter the sigmoidal relationship of insulin released to glucose concentration. The effect of PMA on insulin secretion from the islet beta-cells persists and a challenge with glucose alone, subsequent to a pulse of PMA, elicits an augmented insulin release response.
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PMID:Phorbol myristate acetate: effect of a tumor promoter on insulin release from isolated rat islets of Langerhans. 36 26

A 34-year-old woman had episodes of hypoglycemic attack 8 years after a surgical resection of a retroperitoneal hemangiopericytoma. In spite of normal levels of serum IRI, insulin radioreceptor assay demonstrated high level of plasma ILA (insulin like activity). The patient underwent resection of a recurrent retroperitoneal tumor with metastatic lesions of the liver. Postoperatively, ILA level in plasma by insulin radioreceptor assay decreased, and hypoglycemic attacks disappeared. Therefore, this associated hypoglycemia was presumed to be not caused by excess glucose consumption by the tumor, not by excess secretion of IRI by the tumor, but caused by the presence of high level of ILA related to the tumor.
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PMID:Retroperitoneal hemangiopericytoma associated with hypoglycemia: report of a case. 39 64

Patient J. B. with metastatic carcinoma of the colon excreted 0.5 to 1.0 g protein daily, about one-third of which was in Molecular Weight Class 30,000 to 60,000. The major component of this class was isolated by gel filtration and ion-exchange chromatography. The purified protein, labeled JBB5, contained about 11% sialic acid, 8% hexose, and 4% hexosamine. Its molecular weight was between 51,000 and 59,000. It did not react detectably with antisera to any of the recognized normal human plasma proteins. A specific antiserum to JBB5 was raised in the rabbit. Urine from 4% of subjects with nonneoplastic illnesses reacted in double immunodiffusion with anti-JBB5. Thirty-three % positive reactions were obtained with urines from patients with advanced neoplastic disease, the percentage varying from 64% in metastatic cancer of the pancreas to 15% in chronic lymphocytic leukemia.
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PMID:Isolation and characterization of the glycoprotein (JBB5) in the urine of a patient with carcinoma of the colon. 40 9


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