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)

A urinary enzyme pattern and kidney tissue pattern were investigated simultaneously in 117 urologic patients. In contrast to all other renal disorders only the sixteen malignant tumors of the kidney showed a significant drop of gamma-GT in tumor tissue and urine. So far urinary enzymology has been used only as screening test. Measurement of gamma-GT in urine, however, permits the diagnosis of kidney tumors.
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PMID:Diagnosis of renal tumor by gamma-glutamyltranspeptidase (EC 2.3.2.2). 0 90

The Morris hepatoma 5123D after at least two passages in F1 (Buffalo X Wistar) rats shows quicker growth than the original tumor and bearers of it have much lower gamma-glutamyltranspeptidase activity in serum, urine, tumor and in some other organs. This new variant of the hepatoma was labeled as hepatoma 5123D/AS. Simultaneous implantation of hepatomas 5123D/AS and 5123D in the same rats prevents the increase of serum gamma-glutamyltranspeptidase activity. After surgical removal of the former tumor, the enzyme activity in serum quickly increases. No significant differences in some other peptidase activities were observed between the variant and hepatoma 5123D.
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PMID:Effect of passages of Morris hepatoma 5123D in F1 (Buffalo X Wistar) rats on permanent decrease of gamma-glutamyltranspeptidase activity. 1 9

gamma-Glutamyl transpeptidase activity was detected in rat ascites tumor cells (LY-5) suspended in Hanks' balanced saline solution using L-gamma-glutamyl-p-nitroanilide as a substrate. Whole-cell suspension of the tumor cells exhibited full activity of the enzyme without detectable cell disruption under the conditions examined. Various amino acids, transported through specific membrane carriers, did not affect the accessibility of substrate for the enzyme. An inhibitor of sodium-dependent transport systems of amino acids caused no significant change in the rate of enzyme catalysis. Like glutathione or S-methylglutathione, S-acetyldextran (mol. wt 215000) derivative of glutathione, which is believed to be unable to penetrate into intact cells, caused marked inhibition of the rate of p-nitroaniline release from the synthetic substrate by the tumor cells. These data indicated that the active site of the enzyme faced to the outer surface of the cells. gamma-Glutamyl transpeptidase of the tumor cells was successfully affinity-labeled by 6-diazo-5-oxo-L-norleucine, a glutamine analog, without causing detectable change in the viability of the cells under the conditions examined. The rate of transport of alanine, leucine, glycine and glutamine into cells was not affected by the inactivation of this enzyme with the affinity label. Thus, the activity of gamma-glutamyl transpeptidase located on the outer surface of tumor cell membrane does not seem to be requisite for the transport process of amino acids.
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PMID:gamma-Glutamyl transpeptidase in rat ascites tumor cell LY-5. Lack of functional correlation of its catalytic activity with the amino acid transport. 2 Oct 85

The activities of gamma-glutamyl transpeptidase (gamma-GTP), alkaline phosphatase (A-p), and leucine aminopeptidase (LAP) were examined in 18 cases of hepatomas. The activity of gamma-GTP was most remarkable in the hepatoma consisting of small to medium-sized tumor cells showing the least atypism. The enzyme activity found in the type composed of large tumor cells resembled that of normal liver and was considered to be the most mature form of the neoplasm. This enzyme was not found in the immature type composed of small typical tumor cells. A-P activity was seen in only a few cases of hepatoma; conspicuous in one case showing immature features and sporadically in one case with florid histological pattern. The activity of this enzyme could not be confirmed in the type demonstrating marked gamma-GTP activity. LAP activity was noted in the majority of cases, especially marked in the medium-sized tumor cells, but there was hardly any connection between this enzyme and histological type. In general, the cases demonstrating positive gamma-GTP activity tended to show LAP activity. Although the activity of gamma-GTP and that of A-p usually showed an inverse relation, all three enzymes demonstrated almost equal activity in the type showing a florid histological pattern.
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PMID:Enzyme histochemical study on hepatoma--the relation between enzyme activity and histological type. 2 15

Highly purified fractions of gamma-glutamyl transpeptidase [gamma-glutamyltrinsferase; (5-glutamyl)-peptide:amino-acid 5-glutamyltransferase, EC 2.3.2.2] from normal and malignant rat mammary tissue were prepared. Analyses by isoelectric focusing indicate the existence of at least 12 enzymatically active species. The gamma-glutamyl transpeptidase from the tumor tissue had a greater proportion of the activity concentrated in the more negative species than the enzyme from normal tissue. Treatment of the two enzyme preparations with neuraminidase (acylneuraminyl hydrolase, EC 3.2.1.18) greatly reduced this difference. When whole tissue homogenates were treated with papain to solubilize the enzyme and then focused, the same relationship held. The neuraminidase activities in the two homogenates were similar, but the sialytransferase activity (CMP-N-acetylneuraminate:D-galactosyl-glycoprotein N-acetylneuraminyltransferase, EC 2.4.99.1) of the tumor homogenate was 13 times that of the normal mammary homogenate. These observations suggest that the gamma-glutamyl transpeptidase of the tumor is more heavily sialylated than that from the normal tissue, possibly reflecting the greater sialyltransferase activity of the tumor.
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PMID:Differences in the isoelectric focusing patterns of gamma-glutamyl transpeptidase from normal and cancerous rat mammary tissue. 2 38

Combinations of carcinoembryonic antigen (CEA), gamma glutamyl transpeptidase (GGT), pregnancy-associated macroglobulin (PAM) and placenta-like alkaline phosphatase (PLAP) were studied in groups of patients with ovarian and cervical cancer. In ovarian cancer, only CEA and PLAP levels appeared to reflect tumor burden and were complementary in detecting active disease. In cervical cancer, CEA and GGT reflected tumor burden, while PLAP showed just the reverse--the highest degree of positivity being present in minimal disease. PLAP positivity was even more pronounced in patients with cervical dysplasia and carcinoma in situ while CEA and GGT were negative. The data indicate that the use of marker combinations can improve our capacity to detect minimal disease and provide information regarding tumor biology that may not be available by studying individual markers or by other means. It remains to be determined whether the use of tumor markers can influence existing therapy sufficiently to alter the outcome in cancers which are notoriously difficult to treat.
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PMID:Carcinoembryonic antigen (CEA) and other tumor markers in ovarian and cervical cancer. 3 May 36

A method for the purification of a membrane-bound glycoprotein, gamma-glutamyltranspeptidase ((gamma-glutamyl)-peptide:amino-acid gamma-glutamyltransferase, EC 2.3.2.2), from a transplantable rat mammary tumor (13762 MT) is described. The properties of the tumor enzyme were compared with those of gamma-glutamyltranspeptidase similarly isolated from mammary tissue of nonpregnant multiparous rats. Evidence has been presented elsewhere that the mammary and tumor enzymes exist as groups of species differing in isoelectric point and that the tumor enzyme contains more of the those species with lower isoelectric points. In this study the normal and tumor enzyme preparations are found to be identical or very similar in regards to the effect of papain on molecular size, the ratios of the enzymatic activities as measured with various amino acids, the Km for gamma-glutamyl-p-nitroanilide, and the Ki for inhibition by glutathione. Neuraminidase treatment had no effect on these catalytic properties. The properties observed were generally similar to those previously reported for highly purified rat kidney preparations.
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PMID:Purification and comparison of several catalytic parameters of the gamma-glutamyltranspeptidase of rat mammary adenocarcinoma (13762) and of normal rat mammary gland. 3 3

In 22 patients with chronic pancreatitis and 16 patients with pancreas neoplasms gamma-glutamyltranspeptidase (GGTP) and alanine arylamidase (AAP) in serum were measured and the isoenzymes were determined by gel electrophoresis on Agar. No specific isoenzyme pattern was found for chronic pancreatic diseases in a comparative investigation with a group of 19 patients suffering from hepatobiliary diseases. Two fractions of AAP and GGTP isoenzymes were found on agar gel electrophoresis: alpha-1 and alpha-2 (GGTP between alpha-2 and beta-globulin). The alpha-1 fraction of AAP and GGTP seems to be a specific liver isoenzyme. The slower fraction of both enzymes was also found in chronic pancreatic diseases and cholestatic diseases as in neoplasms of liver, pancreas and biliary tract. Practical importance of the findings is diminished by large variation coefficients of the results. A significantly low ratio of alpha-1 to alpha-2 fraction (or beta-globulin) on electrophoresis of the isoenzymes of AAP and GGTP was found in the group with neoplasm of pancreas (especially neoplasm of the pancreas head) as compared to the group with intrahepatic cholestasis. The possible causes and diagnostic importance of the findings are discussed.
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PMID:[Isoenzymes of alanine arylamidase (AAP, EC 3.4.11.2) and gamma-glutamyltranspeptidase (GGTP, EC 2.3.2.2) in chronic pancreatitis and pancreas neoplasm (author's transl)]. 23 68

Plasma carcinoembryonic antigen (CEA) and gamma glutamyl transpeptidase (GTP) were studied in 24 patients with cancer metastatic to the uveal tract. Eighty-three percent demonstrated elevated CEA levels, while only 36% (49 of 135 patients) with primary uveal melanoma showed elevated levels. While none of the uveal melanoma patients had a CEA value greater than 10 ng/ml, 58% (14) of the patients with metastatic tumors to the uvea had values greater than 10 ng/ml. Forty-six percent (11) of patients with metastatic tumors to the uvea demonstrated elevated GTP levels that correlated with documentation of liver metastases. Ninety-two percent of the patients with metastatic cancer to the uvea had either an elevated CEA or GTP level. When used together, plasma CEA and GTP levels appear to be helpful in differentiating metastatic tumors to the uvea from primary uveal melanomas. These assays also appear to be useful in determining tumor burden and concurrent hepatic involvement in patients with metastatic tumors to the uvea.
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PMID:Evaluation of metastatic cancer to the eye. Carcinoembryonic antigen and gamma glutamyl transpeptidase. 84 92

Three patients had supratentorial malignant brain tumors 7 to 9 years after prophylactic central nervous system (CNS) treatment for acute lymphocytic leukemia or malignant T-cell lymphoma. Therapy was administered at the age of 3 to 8 years and included cranial irradiation (total dose, 1800 to 2400 cGy) and intrathecal methotrexate. The brain tumors had histologic and immunohistochemical features of primitive neuroectodermal tumors (PNET), including neuroblastic rosettes, rhythmic arrangement of tumor cells, and immunohistochemical expression of glial, and in one patient neuronal, marker proteins. Using polymerase chain reaction-mediated DNA amplification from paraffin-embedded tissues and subsequent DNA sequence analysis, an activating point mutation was detected in the K-ras protooncogene in one tumor. This mutation was a G to A transition in position 2 of codon 12, substituting aspartate (GAT) for glycine (GGT). This type of mutation has not been observed before in human brain tumors, but it is frequent in radiation-induced murine lymphomas. These observations suggest that PNET can be induced after completion of the embryonal and fetal development of the human CNS. Oncogene-activating point mutations may represent a pathogenetic mechanism involved in the genesis of radiation-induced brain tumors.
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PMID:Primitive neuroectodermal tumors after prophylactic central nervous system irradiation in children. Association with an activated K-ras gene. 131 30


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