Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.1.2.13 (aldolase)
 3,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Isozyme patterns of 23 different enzymes were compared in normal, benign, and malignant breast tissues; in MCF-7 cells; and in organoids of normal human breast tissue. Benign lesions generally showed isozyme patterns similar to those of normal tissues. Lactate dehydrogenase isozyme 5 was significantly increased in malignant tumors; MCF-7 cells had only lactate dehydrogenase (L-lactate:NAD oxidoreductase; EC 1.1.1.27). The mitochondrial form of malate dehydrogenase was also significantly increased in human malignant tumors; this was especially evident when comparing tumor and apparently uninvolved breast tissue from the same patient. The K4 isozyme of pyruvate kinase was the major form in most malignant breast tumors, but in only 41% of normal tissues, 30% of fibrocystic disease specimens, and 46% of fibroadenomas. A more anodal band of pyruvate kinase, probably a K3M or K3Kpm hybrid, predominated in most normal and benign tissues, but in only 63% of primary and 56% of secondary tumors. All specimens had predominantly creatine kinase BB, aldolase A4, and hexokinase I. Traces of aldolase A3C and of hexokinase II were observed in some tumors. None of the tumors had the Regan variant of alkaline phosphatase. The isozymes of lactate and malate dehydrogenases and of pyruvate kinase appear to be the most promising as putative tumor markers.
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PMID:Isozyme patterns of normal, benign, and malignant human breast tissues. 664 May 38

The time courses of activities of aldolase, glyceraldehyde-3-phosphate dehydrogenase, hexokinase and pyruvate kinase were determined in stimulated rat thymocytes at 24 h intervals during a period of 72 h of culture. In parallel the mRNA levels of these enzymes were analysed by Northern blotting with specific probes. Both the enzyme activities and the corresponding mRNA levels reached their maxima 48 h after stimulation coinciding with the S-phase of the cell cycle. The isozyme types of aldolase and hexokinase in resting and in mitogen-stimulated rat thymocytes were identified by Northern blot hybridisation using isozyme-specific probes. In these cells the aldolase A is expressed, whereas type B and C could not be detected. The transcription of the aldolase A gene can be regulated by two different promoters. Depending on the alternative usage of the promoters the aldolase A-specific mRNA either contains the non-translated exons M1 or AH1. In rat thymocytes the promoter proximal to the exon AH1 is used while the expression of mRNA I, the type characteristic for muscle tissue, was not observed. In contrast to aldolase two isozyme types of hexokinase were detected. Hexokinase I as well as hexokinase II were present in thymocytes whereas hexokinase III was not detectable. A shift in the isozyme pattern was not observed during the cell cycle progression.
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PMID:Expression of glycolytic isozymes in rat thymocytes during cell cycle progression. 780 92

Based on the neurotrophic properties of astrocytes in response to ischemia, the current work focuses on the mechanism for cultured astrocytes to adapt to a hypoxic environment. Intracellular glucose levels in primary cultured rat astrocytes exposed to hypoxia fell by 30% within 24 h, in parallel with a decrease in glycogen stores. Glycolytic metabolism was crucial for cell survival during hypoxia, as 2-deoxyglucose resulted in rapid ATP depletion and cell death. The mechanism for maintaining glucose levels under these conditions appeared to be mobilization of glycogen stores, rather than increased extracellular uptake of glucose, as gluconolactone (an inhibitor of beta1-4 amyloglucosidase) induced a rapid fall in cellular ATP in cultures subjected to hypoxia, whereas cytochalasin B was without affect. Addition of cycloheximide diminished the viability of astrocytes in hypoxia, suggesting an obligatory role of de-novo gene expression to respond to hypoxia. Consistently, the results of differential display suggested the induction of glycolytic enzymes, including aldolase A (EC 4.1.2.13), hexokinase II (ATP: D-hexose 6-phosphotransferase, EC 2.7.1.1), and triosephosphate isomerase (EC 5.3.1.1) in the hypoxic culture. Marked induction of these glycolytic enzymes in hypoxic astrocytes was confirmed by Northern blot analysis. These data provide a theoretical basis to understand the ability of astrocytes to tolerate ischemic condition.
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PMID:Exposure of cultured primary rat astrocytes to hypoxia results in intracellular glucose depletion and induction of glycolytic enzymes. 1064 Jun 73