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

Under study was anaerobic glycolysis, the activity of hexokinase, lactate dehydrogenase, gluco-6-phosphatase in rat kidneys in dimethylnitrosamine (DMNA) induced tumors in them. DMNA was administered perorally in the dosage of 10 mg/Kg during 4 weeks (25 mg per rat). Following 8 months tumors developed in the renal cortical substance. The tumor tissue, the renal cortical substance adjacent to the tumor, and the renal cortical substance without macroscopic tumor signs have been studied. An increased glycolysis, hexokinase and lactatedehydrogenase activity were noted, whereas the activity of glucoso-6-phosphatase was diminished in all tissues under examination. Changes of all indices were mostly pronounced in tumor tissue and least significant--in the renal cortical layer without any macroscopic tumor signs.
 ...
PMID:[Carbohydrate metabolism in the kidneys of rats with dimethylnitrosamine-induced tumors]. 18 57

Oxidoreductases were studied histochemically in 162 cases of neuroectodermal tumors. In order of decreasing activity in the cytoplasma these enzymes could be arranged as follows: NADH diaphorase, lactate dehydrogenase, NADPH diaphorase, glutamate dehydrogenase, glucose-6-phosphate dehydrogenase, isocitrate dehydrogenase, succinate dehydrogenase, malate dehydrogenase. The weak activity of Krebs cycle enzymes and the relatively strong activity of other oxidoreductases, particularly of lactate dehydrogenase, permits to conclude that glycolysis prevails over oxidative processes in neuroectodermal tumor cells. But this should not be interpreted as a decrease of the Krebs cycle enzymes in astrocytoma and oligodendroglioma cells as compared with their parent cells because the latter themselves display a weak activity of these enzymes. A real decrease of Krebs cycle enzyme activity was established only for tumors, the parent cells of which are characterized by a strong (in choroid-papillomas) or moderate (in ependymomas) activity of these enzymes. Many neuroectodermal tumors, in particular those of astrocytic origin, demonstrate a certain correlation between the amount of cytoplasm and oxidoreductase activity. This results in enzymatic polymorphism of the tumor tissue. A certain similarity was established of the oxidoreductase activity in tumor cells and in reactive hypertophic astrocytes. This indicates that both tumor cells and reactive astrocytes may in certain conditions utilize similar mechanisms of increased metabolism. The oxidoreductase activity correlates not with the grade of anaplasia but with different directions of anaplasia reflected in different variants of neuroectodermal tumors. The concept "anaplasia" includes not only certain degrees of dedifferentiation of tumor cells but, as it has been shown histochemically, also an increase of metabolic processes in the tumor cell cytoplasma.
 ...
PMID:Histochemistry of oxidoreductases, enzymatic polymorphism and anaplasia of neuroectodermal tumors. 18 68

A 56-year old woman, with the diffuse form of bronchioloalveolar cell carcinoma, developed massive bronchorrhea, resulting in severe fluid and electrolyte depletion when her oral intake was compromised. Chemical analysis of the bronchial secretions and the ultrastructural features of the tumor cells support the concept of an active secretory process. The lactic dehydrogenase (LDH) isoenzyme pattern of the fluid is similar to that found in fetal cells. The neoplastic cells may acquire a more primitive LDH pattern.
 ...
PMID:Salt-wasting bronchorrhea and its mechanisms. 19 43

In cells of ascites Zajdela hepatoma in different terms after irradiation of the abdominal region in tumor-bearing rats (doses of 500, 700 and 1000 rad) there were found a reduction of highly active and an increase of insignificantly active normal isoenzymes of lactate dehydrogenase and also disorders in the content of acid phosphatase.
 ...
PMID:[Effect of radiation on the activity of lactate dehydrogenase and acid phosphatase isoenzymes of Zajdela hepatoma]. 20 7

An ultramicrochemical technique has been adapted to the evolution of enzyme profiles within individual human mammary tumors. Tandem observation of adjacent stained and lyophilized sections permitted dissection of microgram quantities of freeze-dried material within confirmed regions of malignancy. Enzymes frequently monitored to examine glycolytic, respiratory, and metastatic capacity were microanalyzed successfully: lactic dehydrogenase (LDH), phosphoglucose isomerase (PGI), malate dehydrogenase (MDH), acid phosphatase (AP), aldolase (ALD), glucose-6-phosphate dehydrogenase (G6PDH), pyruvate kinase (PK), alpha-glycerophosphate dehydrogenase (alpha-GOPDH), hexokinase (HK), and phosphofructokinase (PRK). All enzyme activities were higher in infiltrating ductal carcinomas than in fibroadenomas. Extracts of tumor cells mixed in varying proportions with brain or muscle extracts of rat evidenced no modification of expected activity. The technical adaptation described provided a sensitive methodology to resolve problems of relication, profile analysis, sample quantity, and selectivity within heterogeneous tissues.
 ...
PMID:Application of a microchemical technique to the elucidation of enzyme activity profiles within single human mammary tumors. 20 41

Most of the available human breast tumor cell lines have been derived from pleural effusions. The two cell lines herein described, BT-474 and BT-483, were derived from solid, invasive ductal breast carcinomas. Both are epithelial and neoplastic as judged by their general morphology, their fine structure, and their ability to produce growing nodules in nude mice and colonies in soft agar and methocel. BT-474 and BT-483 are human as expressed by chromosome morphology and aneuploid with a modal number of 55 and 72 chromosomes, respectively. Trypsin-Giemsa banding did not reveal the presence of obvious HeLa markers, and the glucose 6-phosphate dehydrogenase electrophoretic migration pattern was of the B-type. Furthermore, the migration of lactic dehydrogenase, malic dehydrogenase, and 6-phosphogluconate dehydrogenase isoenzymes was consistent with a human pattern and different from that of the mouse, rat, or hamster. Quarterly tests to detect the presence of aerobic and anaerobic mycoplasmas were repeatedly negative. A culture medium containing insulin, increased amounts of amino acids, vitamins, and glucose facilitated the isolation of the tumor cells. Cell replication was maintained with 10% fetal calf serum absorbed with activated charcoal and dextran. No production of alpha-lactalbumin was detected by radioimmunoassays, but high levels of progesterone receptors were found in both cell lines.
 ...
PMID:Isolation of two human tumor epithelial cell lines from solid breast carcinomas. 21 72

The isoenzymic spectrum and lactate dehydrogenase activity (LDH) were studied in tumor and pectoral muscle of both chicken and adult hens on the 6th, 10th and 15th day after their infection with the Rous sarcoma virus. On the 14th day, unlike the muscles of intact hens, in the tumour the content of LDH-5 increases and that of rapidly migrating fraction LDG-1 and LDG-2 decreases. In pectoral muscles unaffected by the tumour (on the opposite side of the sternum) there is a tendency to an increase in LDH-4 content and to a decrease in LDH-1 and LDG-2 content, which is followed by a decreasing proportion of N/M subunits.
 ...
PMID:[Lactate dehydrogenase isoenzyme in Rous sarcoma and muscle tissue of tumor-bearing hens]. 21 72

The Burkitt-like lymphoma is extremely rare. It shows a predominance of presentation in abdominal and pelvic sites and an older median age as compared to the endemic Burkitt's lymphoma. Both are independent prognostic determinants and reflect a poor prognosis. This might be the reason for the low response rate to cytotoxic treatment. Cyclophosphamide is a substantial part of any chemotherapeutic regimen used. Serum lactic dehydrogenase (LDH) levels are closely correlated with the extent of tumor mass and the response to therapy. Chemotherapy might be associated with serious metabolic complications including hyperkalemia, lactic acidosis, anuria, and sudden death from lethal embolization of the lung. In contrast to Burkitt's lymphoma, the Burkitt-like tumor has no association with the Epstein-Barr-virus. In both lymphomas a translocation from the 8q onto 14q chromosome occurs being a characteristic marker for these malignancies.
 ...
PMID:[Burkitt-like lymphoma: diagnosis, clinical features, and response to chemotherapy (author's transl)]. 22 8

With the use of circulating human lactate dehydrogenase (LDH) as a tumor marker, growth and remission of human tumor lines SW480, HEp-2, and Clouser, implanted into female BALB/c athymic nude mice, were followed during therapy. Three types of therapy were used: X-radiation, cyclophosphamide, and diphtheria toxin. After therapy tumor sizes were measured with calipers and compared to changes in the levels of circulating human LDH. Changes in LDH levels paralleled changes in tumor size, but the enzyme fluctuations were more pronounced. Mice bearing intraperitoneally growing SW480 and HEp-2 tumors were effectively treated with diphtheria toxin, and the measurement of circulating LDH was examined as a parameter for gauging the effectiveness of chemotherapy on tumors that could not be visualized. Circulating human LDH can be used to detect intraperitoneal tumor growth and/or remission and to predict death of the animal due to the tumor.
 ...
PMID:Monitoring the therapy of human tumor xenografts in nude mice by the use of lactate dehydrogenase. 28 69

The concept of tumor markers was reviewed, and the potential uses of markers of central nervous system (CNS) tumors and methods for their evaluation were discussed. Markers examined included lactate dehydrogenase, aspartate aminotransferase, fructose-bisphosphate aldolase, the polyamines, desmosterol, and several other enzymatic, nonenzymatic, and immunologic markers. Data collated from the clinical studies surveyed showed isocitrate dehydrogenase, desmosterol, and the polyamines to have the greatest potential utility in the diagnosis of CNS tumors.
 ...
PMID:Biochemical markers of central nervous system tumors measured in cerebrospinal fluid and their potential use in diagnosis and patient management: a review. 38 10


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>