Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.5 (5'-nucleotidase)
 3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The localization of alkaline phosphatase in HeLa cells was examined by electron microscopic histochemistry and subcellular fractionation techniques. Two monophenotypic sublines of HeLa cells which respectively produced Regan and non-Regan isoenzymes of alkaline phosphatase were used for this study. The electron microscopic histochemical results showed that in both sublines the major location of alkaline phosphatase is in the plasma membrane. The enzyme reaction was occasionally observed in some of the dense body lysosomes. This result was supported by data obtained from a subcellular fractionation study which showed that the microsomal fraction rich in plasma membrane fragments had the highest activity of alkaline phosphatase. The distribution of this enzyme among the subcellular fractions closely paralleled that of the 5'-nucleotidase, a plasma membrane marker enzyme. Characterization of the alkaline phosphatase present in each subcellular fraction showed identical enzyme properties, which suggests that a single isoenzyme exists among fractions obtained from each cell line. The results, therefore, confirm the reports suggesting that plasma membrane is the major site of alkaline phosphatase localization in HeLa cells. The absence of any enzyme reaction in the perimitochondrial space in these cultured tumor cells also indicates that the mitochondrial localization of the Regan isoenzyme reported in ovarian cancer may not be a common phenomenon in Regan-producing cancer cells.
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PMID:Plasma membrane localization of alkaline phosphatase in HeLa cells. 5 27

A plasma membrane ectoenzyme in mammalian cells, 5'-nucleotidase, was evaluated as a marker for ovarian carcinoma. Activities of this enzyme were determined in homogenates from normal (N = 17) and malignant ovaries (N = 17), as well as in the sera from control women (N = 35), ovarian cancer patients with active disease (N = 24), and those in clinical remission (N = 9). A significant reduction of the activity of 5'-nucleotidase was observed in tumor homogenates compared with homogenates from normal ovaries. Levels of this enzyme in the sera of ovarian cancer patients were higher than in control women, suggesting the possibility of shedding of this enzyme from the tumor cell surface to the systemic circulation of the host. The diagnostic value of serum 5'-necleotidase levels was compared with another enzyme marker for ovarian carcinoma, viz. serum glycoprotein:galactosyltransferase. The upper limit of normal was set at 2 SD higher than the normal mean. Elevation of serum 5'-nucleotidase was observed in 12/24 (50%) patients with active disease, and 1/9 (11%) patients with clinical remission. In contrast, serum glycoprotein:galactosyltransferase was elevated in all the serum samples from patients with active disease and in none of those with clinical remission. There was some correlation between the serum levels of 5'-nucleotidase and those of glycoprotein:galactosyltransferase (0.01 less than P less than 0.05). Elevation of 5'-nucleotidase in the serum of these patients was not due to liver metastasis. Serum 5'-nucleotidase levels seem to correlate with disease status in some ovarian carcinoma patients, but in general it is inferior to serum glycoprotein:galactosyltransferase as a tumor marker.
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PMID:Evaluation of 5'-nucleotidase as an enzyme marker in ovarian carcinoma. 626 38

Adenosine deaminase (ADA) and 5'-nucleotidase (5'-NT) activities were measured in sera of patients with ovarian cancer and patients with benign ovarian tumour. The results were compared with that of a control group consisting of healthy women. ADA levels were significantly increased (P<0.001) in the ovarian cancer group (n=50) but not in the benign group (n=28) when compared to the controls (n=20). The results indicate that ADA and 5'-NT levels may help to differentiate malignant conditions from benign tumours of the ovary in addition to the existing tests such as serum CA-125 levels and histopathological study.
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PMID:Evaluation of serum adenosine deaminase and 5'-nucleotidase activities as probable markers in ovarian cancer. 2310 61