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)

Human microvessels were isolated and cultured from non-neoplastic cerebral tissue specimens resected for the treatment of seizure disorders and from malignant glial tumors. After 1-2 weeks, cobblestone patterned plaques of cells were isolated and cultured from these microvessels. Cell lines positive for Factor VIII antigen and negative for glial fibrillary acidic protein were designated as endothelium. Endothelium from both tissue sources produced gamma-glutamyl transpeptidase in response to glial cell conditioned media. Tumor derived microvessel endothelium had decreased longevity in culture when compared to normal microvessel endothelium. Tumor derived endothelium also formed less extensive intercellular junctional complexes in vitro. The isolation and characterization of human cerebral microvessel endothelium derived from non-neoplastic tissue and glial tumors may lead to a further understanding of the role of endothelium in tumor growth and vascular permeability alterations.
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PMID:Human cerebral endothelium: isolation and characterization of cells derived from microvessels of non-neoplastic and malignant glial tissue. 211 73

To investigate the prognostic factors in Western patients with hepatocellular carcinoma, 206 patients with confirmed diagnoses of hepatocellular carcinoma were studied in terms of survival. All patients were diagnosed between 1983 and 1987. A multivariate survival analysis (Cox regression model) using clinical, biochemical, ultrasonographical and pathological data obtained at diagnosis disclosed that bilirubin (p = 0.0001), ascites (p = 0.0001), toxic syndrome (defined by the presence of weight loss greater than 10% premorbid weight, malaise and anorexia) (p = 0.009), blood urea nitrogen (p = 0.025), tumor size (p = 0.001), gamma-glutamyltranspeptidase (p = 0.0006), age (p = 0.0005), serum sodium (p = 0.003) and presence of metastases (p = 0.002) were independent predictors of survival. According to the contribution of each of these factors to the final model, a prognostic index was constructed allowing division of patients in different groups according to their relative risk of death: RRD = EXP (Age x 0.03 + Ascites x 0.8281 + BUN x 0.0137 + Serum sodium x (-0.0538) + gamma-Glutamyltranspeptidase x 0.0019 + Bilirubin x 0.0734 + Tumor size x 0.33 + Toxic syndrome x 0.4965 + Metastases x 0.55). These results facilitate the stratification of hepatocellular carcinoma patients to design and evaluate future controlled trials.
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PMID:Prognostic factors of hepatocellular carcinoma in the west: a multivariate analysis in 206 patients. 217 Feb 67

We studied the creatine kinase (CK) isoenzyme pattern in sera from 332 patients affected by hepatic cirrhosis and several neoplastic diseases (102 cirrhosis, 36 hepatocarcinoma, 16 metastatic liver tumor, 40 breast cancer, 18 other neoplastic diseases and 120 cases of leukemia or lymphoma) to evaluate both its diagnostic utility for cancer diagnosis and its power as a prognostic index. Type-2 macro CK (mitochondrial creatine kinase) was detected, with no statistical difference in cirrhosis (14%), hepatocarcinoma (16%), metastatic liver tumor (31%), breast cancer (5%) and other tumors (6%). It was not detected in any patient with leukemia or lymphoma. The presence of type-2 macro CK was unrelated to the stage of either cirrhosis or hepatocarcinoma, according to Child and Okuda, respectively, nor was it correlated to serum cytolytic enzyme levels or to gamma-globulin levels. In cirrhotics, type-2 macro CK was not linked to serum levels of the following tumor markers: alpha-fetoprotein, pseudouridine and gamma-glutamyltransferase isoenzymes complexed to low-density lipoprotein. In addition, the atypical band persisted in several patients with cirrhosis monitored for six months who did not show any evidence of evolution toward hepatocarcinoma. Thus, type-2 macro CK has poor diagnostic sensitivity for neoplastic diseases, and lacks prognostic value both in cirrhosis and neoplastic diseases.
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PMID:Serum type-2 macro-creatine kinase isoenzyme is not a useful marker of severe liver diseases or neoplasia. 228 11

The ability of methyl-deficient, amino-acid-defined diets to produce enzyme-altered foci was quantitatively determined in the livers of rats treated both with and without an initiating dose of diethylnitrosamine (DEN). Male weanling F-344 rats were fed a complete, amino-acid-defined diet for 1 week. They were then injected i.p. with a single dose of DEN (20 mg/kg body weight) and fed the complete diet for an additional week. Forty animals in each dose group were then maintained for 5-38 weeks on the complete diet (diet 1) or one of the three methyl-deficient diets customarily used in this laboratory: diet 2, devoid of methionine and choline; diet 3, devoid of methionine only; and diet 4, devoid of choline only. In diets 2 and 3, methionine was replaced by equimolar amounts of its metabolic precursor, DL-homocystine. Ten animals per group were killed 8, 12, 17, 24 and 41 weeks after DEN initiation. For 2 weeks prior to being killed, each group was maintained on the complete diet to minimize the histological abnormalities due to acute toxicity of the diets. Serial sections of the livers were obtained, stained sequentially for gamma-glutamyltranspeptidase, ATPase and glucose-6-phosphatase, and the quantitation of the focal lesions scored by these markers was carried out by quantitative stereology. The results indicated that, regardless of the enzyme marker(s) examined, there was a general correspondence between the volume and number of altered hepatic foci (AHF) formed and the previously described tumor-promoting activities of each diet. Thus, while all DEN-treated groups contained significant numbers of AHF 24 weeks after initiation, only the diet-2-fed animals displayed such foci at 8 weeks. Similarly, among the uninitiated rats, only those fed diet 2 exhibited the presence of AHF throughout the experimental period. Interestingly, the livers of uninitiated, choline-deficient rats showed a small number of AHF at 24 and 42 weeks; these foci were not observed at all in the corresponding DEN-untreated animals fed diet 3, deficient in methionine only. The results provide evidence that the carcinogenic effects of the methionine- and choline-deficient diet result more from its strongly promoting effect than from any initiating activity by the diet.
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PMID:The effect of choline and methionine deficiencies on the number and volume percentage of altered hepatic foci in the presence or absence of diethylnitrosamine initiation in rat liver. 230 54

Intracarotid infusions of leukotriene C4 (LTC4) were used to selectively open the blood-tumor barrier in rats with RG-2 gliomas. Blood-brain and blood-tumor permeability was determined by quantitative autoradiography using 14C aminoisobutyric acid. Leukotriene C4 (4 micrograms total dose) infused into the carotid artery ipsilateral to the tumor increased twofold the unidirectional transfer constant for permeability within the tumor while no effect on permeability was seen in normal brain. No gamma glutamyl transpeptidase (gamma-GTP) activity was seen in tumor capillaries in contrast to high gamma-GTP in normal brain capillaries. These findings suggest that normal brain capillaries may resist the vasogenic effects of LTC4, while LTC4 will increase permeability in tumor capillaries. This could relate to the ability of gamma-GTP to act as an enzymatic barrier and inactivate leukotrienes in normal brain capillaries. Intracarotid LTC4 infusion may be a useful tool to selectively open the blood-tumor barrier for delivery of antineoplastic compounds.
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PMID:Selective opening of the blood-tumor barrier by intracarotid infusion of leukotriene C4. 233 76

Adult Oryzias latipes were exposed to 50 mg of diethylnitrosamine per liter of water for 5 wk and then transferred to clean water for an additional 15 wk. Response of the liver during the first 6 wk were analyzed by enzyme histochemistry and by high-resolution light and transmission electron microscopy. After 1 wk, cytotoxicity was apparent at the light microscopic level by piecemeal necrosis and phagocytosis apoptosis by adjacent hepatocytes and resident macrophages. Spongiosis hepatis and inflammation, found as early as wk 3, were not widespread until wk 6. Glycogen depletion and multifocal increases in gamma-glutamyl transpeptidase were found as early as 3 wk. At 5 wk, macrophage infiltration and aggregation and hepatocyte lysosome proliferation were revealed by an increase in cells staining for acid phosphatase. In addition, a subpopulation of macrophages stained positively for glucose-6-phosphate dehydrogenase during wk 6. Other histochemical biomarkers (Mg2(+)-ATPase, DT-diaphorase, uridine diphosphoglucuronyl dehydrogenase) were not altered. Mitotic figures were rare for the entire 6-wk period. At the ultrastructural level, necrotic alterations of some hepatocytes were seen within 24 h. Within 48 h, an apparent reduction of hepatocyte glycogen and cell volume characterized the majority of hepatocytes; this was accompanied by an increase in interhepatocytic space and the length and complexity of the hepatocyte microvillous projections found in the space of Disse. Lipid vacuolar inclusions inhabited space previously occupied by glycogen. Margins of hepatocyte nuclei were irregular, and mitochondria were condensed and their shape altered so that crescentric and elongated profiles were abundant. Lysosomes and residual bodies were increased after 1 wk. The cytoplasmic processes delineating spongiotic lesions were identified as originating from Ito cells. After 4 wk, apparent proliferation of smooth endoplasmic reticulum and retention of transport lipid within its cisternae were seen. The toxic depletion of hepatocytes and the attendant altered cellular environment are discussed in relation to cell-to-cell interactions and the possible contribution of stromal and extracellular matrix changes to liver regeneration and neoplasia.
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PMID:Cytotoxicity phase of diethylnitrosamine-induced hepatic neoplasia in medaka. 238 55

Non transformed epithelial hepatic cells (established cell line and adult rat hepatocytes) treated by liver tumor promoters, phenobarbital and biliverdin, for 24 and 48 h showed a fragmentation and loss of F-actin and a depolymerisation of microtubules. This pattern closely resembles that of transformed cells which were not susceptible to the action of promoters. In liver preneoplastic nodules obtained from rats submitted to an initiation-promotion process, actin almost completely disappeared with the concomitant appearance of a characteristic enzymatic pattern rich in GGT and GST-P. Therefore, cytoskeleton of hepatic cells is a target for tumor promoters and could play a role in promotion mechanism.
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PMID:[Modification of the cellular cytoskeleton and hepatic tumor promotion]. 240 Aug 20

Two antioxidants, butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA), which are widely used as food additives, have been proved in vivo to act as tumor promoters in rodent species. In order to study their mechanisms of action, BHT, BHA and phenobarbital (PB) were tested in vitro on liver epithelial cells isolated from 2-acetylaminofluorene-initiated rats. Interactions of BHT 3 x 10(-6) to 3 x 10(-5) M, BHA 10(-5) to 10(-4) M and of PB 10(-4) to 10(-3) M with cell growth on plastic dishes or in agarose, and with the expression of different proteins (gamma-glutamyltranspeptidase, cytoskeletal proteins, fibronectin) were followed.
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PMID:[In vitro use of a model for studying the effects of tumor promoters in food]. 240 Aug 23

Livers of a natural population of winter flounder from a contaminated site in Boston Harbor were examined for the presence of oncogenes by transfection of DNA into NIH 3T3 mouse fibroblasts. Tissues analyzed contained histopathologic lesions including abnormal vacuolation, biliary proliferation, and, in many cases, hepatocellular and cholangiocellular carcinomas. Fibroblasts transfected with liver DNA samples from 7 of 13 diseased animals were effective in the induction of subcutaneous sarcomas in nude mice. Further analysis revealed the presence of flounder c-Ki-ras oncogenes in all 10 nude mouse subcutaneous tumors analyzed. Direct DNA sequencing and allele-specific oligonucleotide hybridization following amplification of the tumor DNA by the polymerase chain reaction showed mutations in the 12th codon in this gene. Analysis of DNA from all nude mouse tumors as well as the livers from which they were derived showed mutations at this codon. The mutations comprised G.C----A.T or G.C----T.A base changes resulting in substitution of serine, valine, or cysteine for glycine. Liver DNA samples from five histologically normal livers of animals from a less polluted site were ineffective in the transfection assay and showed only wild-type DNA sequences (GGT) at the 12th codon of c-Ki-ras. The prevalence of mutations in this gene region was associated with the presence of liver lesions and could signify DNA damage resulting from environmental chemical exposure.
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PMID:Mutations in c-Ki-ras oncogenes in diseased livers of winter flounder from Boston Harbor. 240 90

This study was undertaken to determine whether gamma-glutamyl transpeptidase (GGT) histochemical activity is expressed during the development of human oral, pharyngeal, and laryngeal squamous neoplasms. Surgical specimens from 46 patients were sampled and unfixed frozen sections were prepared and processed for histopathologic evaluation and histochemical localization of GGT. The patients' tobacco exposure, alcohol intake, and previously diagnosed neoplastic disease were documented. Generalized or patchy GGT histochemical activity was observed in each of 22 squamous cell carcinomas and in each of 33 dysplastic samples. Thus, GGT appears to be expressed during the development of malignant squamous epithelial neoplasms of the oral-pharyngeal-laryngeal region. In addition, the detection of GGT activity in several samples of nondysplastic epithelium, obtained from patients at high risk of developing cancer in this region, raises the possibility that this marker is expressed in very early precancerous sites that have not yet developed the histologic hallmarks of premalignancy.
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PMID:Gamma-glutamyl transpeptidase in precancerous lesions and carcinomas of oral, pharyngeal, and laryngeal mucosa. 240 24


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