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)

The combination of phorbol 12-myristate 13-acetate (PMA) and concanavalin A induces the expression of a new set of glycolytic isozymes in human peripheral lymphocytes. The induced isozyme for each enzyme tested (hexokinase, phosphofructokinase, enolase, pyruvate kinase and lactate dehydrogenase) is usually the muscle form, which is often associated with rapidly dividing tumor cells. Increases in a specific isozyme can account for the 2-5-fold increase in specific activities of the enzyme induced by Con A plus PMA. Increased specific activities and the appearance of the new isozyme forms both occur relatively late, and are probably associated with the G1 or S phase of the cell cycle.
 ...
PMID:Expression of a new set of glycolytic isozymes in activated human peripheral lymphocytes. 216 15

By using Fab'-enzyme labelled immunosorbent assay (ELISA) at a sensitivity of picogram (10(-12) g or pg) level, M-type pyruvate kinase (M-PyK) in the plasma was determined in 47 healthy adults and 26 hepatocellular carcinoma (HCC) patients. The upper limits of M-PyK in the normal male and female were 1.1 and 1.4 ng/ml. The plasma M-PyK in HCC patients was significantly increased about 5 fold of the average normal level with a positive rate of about 95%. In 6 cases of subclinical small hepatocarcinoma and 7 cases of HCC with normal serum alpha-fetoprotein level, the plasma M-PyK was increased, whereas the plasma M-PyK levels were normal in acute or chronic hepatitis and the other benign diseases. After tumor resection, the plasma M-PyK returned to the normal value, but increased again in cases with recurrence, suggesting that the increased M-PyK in the plasma of HCC patients originates from M2-type PyK in HCC tissue. The plasma M2-PyK also increased in patients with carcinoma of the digestive tract, so M2-PyK may become a new marker of malignant tumors.
 ...
PMID:[M2-type pyruvate kinase in the diagnosis of hepatocarcinoma--a pilot study]. 217 28

The specific activity of hexokinase, phosphofructokinase, aldolase, enolase, pyruvate kinase and glucose-6-phosphate dehydrogenase was measured in 41 smooth muscle cell tumors: 20 leiomyomas and 21 cases of leiomyosarcoma. Statistical analysis revealed no significant differences in specific activity between normal smooth muscle tissue and the benign and malignant tumors originating from it. Quantification of the isozyme composition of pyruvate kinase showed a significant shift in isozyme pattern towards K-type subunits in leiomyosarcomas as compared to leiomyomas.
Tumour Biol 1990
PMID:Activity of glycolytic enzymes and glucose-6-phosphate dehydrogenase in smooth muscle proliferation. 237 98

Seventeen renal cell carcinomas (RCC) were classified histologically and investigated for their expression of L- and M2-pyruvate kinase (PK) immunohistochemically. Using monoclonal antibodies we were able to demonstrate L-PK within 15 RCC and two metastases (in thyroid gland and bone) after fixation with aceton and paraffin embedding. In normal renal tissue the enzyme was localized within proximal tubules selectively. No enzyme reaction of L-PK could be demonstrated in renal oncocytoma, thyroid carcinoma, and in carcinomas of renal pelvis and lung. In contrast to this the M2-PK was detectable in all tumors and metastases investigated in this study. The results presented in this paper are able to show that (1) RCC derive from the proximal renal tubules, but not the renal oncocytoma, (2) the detection of L-PK may be helpful for identification of metastases of RCC even if they are undifferentiated and (3) there is an enzyme shift from L-PK to M2-PK within tumor cells of RCC resulting in alteration of glucose utilization from energy supply to syntheses of substrates essential for tumor cells.
 ...
PMID:[Immunohistochemical demonstration of L- and M2-pyruvate kinase in primary renal cell carcinomas and their metastases]. 248 32

Activities of key carbohydrate-metabolizing enzymes in biopsied human tissues of hepatocellular carcinoma and related conditions were determined by established methods. Among the enzymes analyzed, fetal-type liver enzymes (low-Km hexokinase, glucose 6-phosphate dehydrogenase, and pyruvate kinase-M2) showed increased activities, and adult-type liver enzymes [glucose 6-phosphatase, fructose 1,6-bisphosphatase, high-Km hexokinase (or glucokinase), and pyruvate kinase-L] showed decreased activities, resulting in undifferentiated enzyme patterns not only in fetal livers and hepatocellular carcinomas but also in livers of acute and chronic hepatitis and liver cirrhosis with or without tumors. Hepatocellular carcinomas showed a general tendency of having greater enzyme deviations than hepatitic and cirrhotic livers. The extent of the enzyme deviation in hepatocellular carcinomas varied considerably from one enzyme to another for each tumor tissue as compared with that in the benign liver diseases. Thus, the phenotypic heterogeneity was important for discriminating between the neoplastic and inflammatory changes in differentiation markers. The enzyme patterns of tumors and their corresponding host cirrhotic livers were unrelated, suggesting that the cirrhotic liver has a significance as preneoplastic state only in terms of having a high incidence of evolving hepatocellular carcinoma.
 ...
PMID:Profiles of carbohydrate-metabolizing enzymes in human hepatocellular carcinomas and preneoplastic livers. 282 76

The isoenzyme composition of lactic dehydrogenase (LDH), pyruvate kinase (PK) and alanine-aminotransferase was determined in the livers of CF-1 mice exposed to 0, 5 or 10 ppm dieldrin in the diet, over a period of 14 months. This study was carried out to evaluate whether the liver tumor promoter dieldrin advances the biological age of CF-1 mouse liver. Oral dieldrin exposure induced a dose-dependent shift towards the fetal types of lactic dehydrogenase and pyruvate kinase, within 1.5 months of initiation of treatment. After the initial shift, no additional dieldrin-dependent changes were found in CF-1 mouse liver throughout the experimental observation period. Thus, the initial shifts in isoenzyme composition of LDH and PK appear to reflect the adaptation of the liver to increased functional demands imposed by dieldrin treatment. The expression of the cytoplasmic A-alanine-aminotransferase isoenzyme decreased with age in untreated control mice. Dieldrin treatment enhanced this process in a dose-dependent manner. These data suggest that dieldrin treatment can accelerate age-dependent changes in gene expression.
 ...
PMID:Dieldrin-induced changes in isoenzyme composition in the livers of CF-1 mice. 282 48

We have compared the pyruvate kinase (PK) isoenzyme pattern of three rhabdomyosarcomas with foetal skeletal muscle tissue of 19 and 23 weeks of gestation, together with adult muscle in relation to immunohistochemical and morphological criteria. In foetal tissue of 19 weeks of gestation a focal immunopositivity for desmin and myoglobin was observed, whereas in tissue of 23 weeks an overall positivity for these proteins was present. Two of the three neoplasms were poorly differentiated and of the alveolar subtype. They were desmin immunoreactive. Some large spindle-shaped cells expressed myoglobin. The third one was more differentiated in microscopic characteristics and all cells showed immunoreactivity for desmin and myoglobin. In the foetal tissues five forms of pyruvate kinase isoenzymes were present with K2M2 as the predominant form. In adult muscle tissue only M4 was present. The tumors were characterized by a profound shift to the K-type, whereas the M4-type was not expressed at all. A difference in isoenzyme composition of pyruvate kinase was found between the morphologically less differentiated tumors and the more differentiated tumor; in the latter more M-subunits were expressed.
 ...
PMID:Characterization of pyruvate kinase from human rhabdomyosarcoma in relation to immunohistochemical and morphological criteria. 291 26

The potent tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) induced a rapid increase in glycolysis in rat thymocytes. The increase in the glycolytic flux was also reflected by elevated fructose 1,6-diphosphate levels. TPA treatment did not result in an increase of hexokinase, phosphofructokinase or pyruvate kinase when measured in cell homogenates. It is suggested that the early increase in glycolysis in TPA treated lymphocytes may result from TPA-mediated increase in glucose transport.
 ...
PMID:12-O-Tetradecanoylphorbol-13-acetate enhances glycolysis in rat thymocytes. 293 56

In 6 patients with breast cancer - of whom specimens of the primary tumor as well as one of its metastases were available for examination - we demonstrated intratumoral and intertumoral heterogeneity in expression of activity of the glycolytic enzymes hexokinase, phosphofructokinase, aldolase, enolase and pyruvate kinase. Heterogeneity also existed in isozyme composition of pyruvate kinase. The transition of the tumors towards normal surrounding breast tissue showed either a sharp drop in activity, or a gradual decrease in activity, corresponding to pushing margins or infiltrative growth of the tumor as was demonstrated by histologic examination of these specimens. Likewise, the shift towards expression of K isozyme of pyruvate kinase in breast cancer compared to normal breast tissue could be demonstrated.
Tumour Biol 1988
PMID:Heterogeneity of glycolytic enzyme activity and isozyme composition of pyruvate kinase in breast cancer. 297 Dec 67

The activities of hexokinase, phosphofructokinase, aldolase, enolase and pyruvate kinase were studied in breast cancer metastases occurring at various sites and compared with the enzyme activities in a series of primary breast cancers. The activities of all enzymes studied were significantly higher in the metastases compared to the primary tumors (p less than or equal to 0.05). However, no changes in the isoenzyme patterns of enolase and pyruvate kinase were observed when the metastases were compared with primary breast cancers. Differences in location of the metastases did not lead to differences in enzyme activities. Our data suggest an association of an increasing rate of glycolysis with tumor progression.
Tumour Biol 1988
PMID:Glycolytic enzyme activities in breast cancer metastases. 297 47


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