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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Six established human sarcoma cell lines (giant cell tumor of bone B-5GT, fibrosarcoma, B-6FS, cystosarcoma phylloides B-19CS, synovial sarcoma U-4SS and two osteogenic sarcomas U-20S and U-393OS) have been studied and compared to the normal B-41FB fibroblastic cells and the HeLa cells. For cytogenetic and isoenzyme characterization both conventional and G banding techniques as well as the mobility of lactate dehydrogenase (LDH) and glucose-6-phosphate dehydrogenase (G-6-PD) were employed. All six sarcoma cell lines had karyotype and LDH patterns of human cells. A study of the chromosome counts distribution revealed a large variability from one sarcoma cell line to the other. There was no evidence of any cross-contamination between the lines or by HeLa cells. This conclusion is based on the detection of G-6-PD with B phenotype, the lack of HeLa marker chromosomes in all sarcoma lines and the presence of Y chromosome in U-4SS and U-393OS derived from male donors. In addition, each sarcoma cell line revealed a group of distinctive marker chromosomes which can serve to identify them and help to control cell line specificity during in vitro culturing.
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PMID:Karyological and isoenzyme characterization of established human sarcoma cell lines. 626 70

Two lymphoid cell lines were established from a patient with chronic lymphocytic leukemia by infecting blood cells with Epstein-Barr virus (EBV). Studies of morphology, glucose-6-phosphate dehydrogenase, malic enzyme, immunoglobulin, and chromosomes of the two lines indicated that one of them originated from leukemic cells while the other arose from residual normal blood cells. The morphology and capacity for immunoglobulin secretion in the line that arose from leukemic cells were similar to those found in EVB-carrying lymphoblastoid cell lines grown from patients without neoplasia and differed from those seen in fresh chronic lymphocytic leukemia cells. These observations suggest that the introduction of EBV into the leukemic cells may have caused them to differentiate in a fashion similar to that noted in normal B cells after exposure to EBV.
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PMID:Establishment of a lymphoid cell line from leukemic cells of a patient with chronic lymphocytic leukemia. 626 8

The histochemical enzyme activity of alkaline phosphatase, nonspecific esterase, 5-nucleotidase, beta-glucuronidase, glucose-6-phosphatase, succinate dehydrogenase, and glucose-6-phosphate dehydrogenase in human bladder cancer was investigated. Tumors of 84 patients, classified into grades I-III according to the WHO classification, were compared with 12 normal and 16 inflamed bladder epithelia. As a rule, loss of alkaline phosphatase activity and a decrease of nonspecific esterase activity was found in most of these tumors. The activity of beta-glucuronidase was decreased and compared with normal tissue, also the activity of 5-nucleotidase. The succinate dehydrogenase activity in tumor tissue was frequently increased, whereas glucose-6-phosphate dehydrogenase did not show any significant reaction.
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PMID:[Histochemical investigations on human bladder cancer (author's transl)]. 626 65

Wilms' tumors from seven patients were dissociated by mechanical and enzymatic means; this technique resulted in single-cell suspensions for five specimens and a few aggregates for two. By dye exclusion, cell viability ranged from 56 to 100% (median, 92%). All seven preparations produced more than five colonies/2 x 10(5) cells plated. Forty-three colonies grown from cells of a glucose-6-phosphate dehydrogenase heterozygote were of the same glucose-6-phosphate dehydrogenase isoenzyme type as the original tumor, indicating that the assay is specific for tumor cells. We attribute the high rate of colony formation to an improved method of cell preparation (combined mechanical and enzymatic dissociation of tumors) which may be applicable to other primary human tumors assayed in the soft agar system.
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PMID:Clonogenic assay for Wilms' tumor: improved technique for obtaining single-cell suspensions and evidence for tumor cell specificity. 629 51

The livers from a total of 51 Sprague-Dawley rats treated with different doses of N-nitrosomorpholine (80-120 mg/l in the drinking water) for up to 14 weeks together with the livers of 28 control animals were histochemically investigated at the cessation of carcinogenic insult and at varying periods thereafter for their glycogen content, basophilia and activities of various enzymes of carbohydrate metabolism: glycogen synthetase, glycogen phosphorylase, glucose-6-phosphatase, glyceraldehyde-3-phosphate dehydrogenase and glucose-6-phosphate dehydrogenase. The enzymatic patterns of normal tissue, preneoplastic and neoplastic lesions were characterized and compared with reference to the morphologically defined stages of tumor development in the liver. The early appearing glycogen storing areas, localized in the peripheral and intermediate lobular regions, did not show significant changes in the histochemically demonstrable activities of the enzymes tested. After cessation of the carcinogen treatment the more pronounced glycogen storage foci which developed within the aforementioned regions of the liver acinus usually showed a reduction in the activities of phosphorylase and glucose-6-phosphatase while the activity of glucose-6-phosphate dehydrogenase, a key enzyme for the pentose phosphate pathway, was increased. The mixed cell foci, neoplastic nodules and tumors which emerged at later stages were characterized by a progressive shift away from glycogen metabolism towards glycolysis and the pentose phosphate pathway, as indicated by an increase in glyceraldehyde-3-phosphate dehydrogenase and glucose-6-phosphate dehydrogenase activities. These changes in enzyme pattern are supportive of a developmental sequence leading from glycogen storage foci through mixed cell foci and neoplastic nodules to hepatocellular carcinomas.
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PMID:Correlative histochemistry of some enzymes of carbohydrate metabolism in preneoplastic and neoplastic lesions in the rat liver. 629 53

Humoral hypercalcemia of malignancy (HHM) most commonly results from secretion by tumors of an unidentified circulating calcemic factor that appears in clinical studies to stimulate both a parathyroid hormone (PTH)-sensitive proximal tubular adenylate cyclase and a distinct PTH-sensitive renal tubular glucose-6-phosphate dehydrogenase complex. In the present study, 8 M urea extracts of tumors from patients with HHM have been shown to contain both in vitro adenylate cyclase-stimulating activity and glucose-6-phosphate dehydrogenase-stimulating activity as detected in a sensitive cytochemical bioassay. Both the adenylate cyclase-stimulating activity and cytochemical bioactivity are due to specific binding of a substance in the tumor extracts to renal PTH receptors, as demonstrated by competitive inhibition studies using the bovine PTH fragment analogue [Nle8,18, Tyr34]bPTH-(3-34) amide. Preincubation with an antiserum to PTH results in no loss of activity in the tumor extract, and the activity appears both on gel filtration and ultrafiltration to be far larger than PTH (estimated Mr 70,000). These studies demonstrate that extracts of tumors from patients with HHM contain a substance that binds to the PTH receptors in the nephron responsible for activation of both the PTH-sensitive glucose-6-phosphate dehydrogenase and the PTH-sensitive adenylate cyclase. This substance is chromatographically and immunologically distinct from PTH. Its role in the genesis of HHM requires further study.
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PMID:Identification of adenylate cyclase-stimulating activity and cytochemical glucose-6-phosphate dehydrogenase-stimulating activity in extracts of tumors from patients with humoral hypercalcemia of malignancy. 629 91

Growth rate, histological course, and polymorphic enzyme pattern (glucose 6-phosphate dehydrogenase, glucose phosphate isomerase, and phosphofructokinase) were studied in eight childhood tumors xenotransplanted serially to nude mice. The growth rate of these tumors (three nephroblastomas, one hypercalcemic renal tumor, three rhabdomyosarcomas, and one malignant histiocytosis) appeared stable for any one particular tumor line. The time interval between two grafts varied from 1 to 3 weeks to 1 to 2 months in correlation with the clinical course of each malignant process. Histological changes were mostly in relation with a progressive dedifferentiation of the grafts. Immunoneutralization of glucose-6-phosphate dehydrogenase and glucose phosphate isomerase made possible the quantification of the stroma reaction in the grafts. A series of ten passages showed the amount of stroma to be constant for a given tumor type but variable from one tumor type to another, except for the malignant histiocytosis which showed an increase in stroma constituent after the sixth passage. One nephroblastoma tumor line showed, during the third passage, a sudden acceleration in the growth rate and complete transformation of the histological and isozymic patterns, which were interpreted as being the result of a murine lymphoma. The fibroblastic form of phosphofructokinase increased in every tumor line, whatever the tumor type. This change may be linked to a progressive dedifferentiation during the passage.
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PMID:Isozyme pattern in serially xenotransplanted childhood tumors. 631 82

146 squamous cell carcinomas of the larynx and pharynx were subjected to a histopathological grading of malignancy ranging from grade 1 up to grade 3. 3-years-survival-rates in G 1 carcinomas were 85%, in G 2 72% and in G 3 15%. Various enzyme histochemical reactions were examined by means of the same test material for the worth for the indication of the cure-rate. A high survival-rate was found for low enzyme activities in the G6PDH- and in LDH-reaction. Strong activities indicated a low survival-rate. The histological grading common with histochemical grading is of prognostic significance. It should be used within a multi-step-check aimed at a more detailed tumor diagnosis before the start of therapy.
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PMID:[Prognostic efficacy of a histologic-cytochemical malignancy grading of squamous cell carcinoma in the head-neck region]. 642 62

The production of 5-S-cysteinyldopa by a newly established melanoma cell line GAK is reported. The cell line was derived from a metastatic inguinal lymph node of vulvar malignant melanoma. The cell line grew well without interruption for over 4 years, GAK cells were proved to have melanin granules and tyrosinase activity in their cytoplasma by Masson's staining and dopa reaction, respectively. Melanin granules were ultrastructually identified as melanosomes in various maturing stages. The chromosomal number varied widely and showed aneuploidly, but the modal chromosomal number was stable in the hypotriploid range. GAK cells were transplanted to nude mice and produced tumors resembling the original. Because glucose-6-phosphate dehydrogenase of GAK revealed a type B (slow) mobility pattern on electrophoresis, the possibility of Hela cell contamination could be completely excluded. High performance liquid chromatography revealed "5-S-cysteinyldopa", a new tumor marker of malignant melanoma, in culture media of GAK cells. The cell line described may serve as a representative model system for basic and clinical studies on malignant melanoma.
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PMID:[A newly established melanoma cell line (GAK) with 5-S-cysteinyldopa phenotype]. 643 Oct 36

Systematic studies of the sequence of cellular changes during hepatocarcinogenesis induced predominantly in rats by stop experiments with N-nitrosomorpholine (NNM) led to the following main results and conclusions: The development of hepatocellular tumors is preceded by a multifocal hepatic glycogen storage disease (glycogenosis). Cytomorphological and cytochemical findings suggest a sequence of focal changes leading from clear and acidophilic glycogen storage foci through mixed cell foci and neoplastic nodules to hepatocellular carcinomas. The clear and acidophilic glycogen storage cells persisting after withdrawal of the carcinogen apparently represent a preneoplastic cell population, the neoplastic transformation of which is accompanied by a gradual reduction of glycogen and a concomitant increase in ribosomes (basophilia). The first appearance and frequency of the different liver lesions investigated was shown to depend on the dose of carcinogen administered. With increasing dose of NNM, the number of focal lesions considerably increased, and this was accompanied by an earlier development of mixed and basophilic cell populations. There was no indication of any reversibility of pronounced focal lesions under the experimental conditions chosen. On the contrary, the foci became larger and acquired phenotypic markers closer to neoplasia independent of further action of the carcinogen. Enzyme histochemically, the majority of the pronounced glycogen storage foci showed a reduction in the activities of glycogen phosphorylase and glucose-6-phosphatase while the activity of glucose-6-phosphate dehydrogenase, a key enzyme for the pentose phosphate pathway, was increased. The mixed cell foci, neoplastic nodules and carcinomas which emerged at later stages were characterized by a progressive shift away from glycogen metabolism towards glycolysis and the pentose phosphate pathway. as indicated by an increase in glyceraldehyde-3-phosphate dehydrogenase and glucose-6-phosphate dehydrogenase activities. These changes in enzyme pattern are in keeping with a developmental sequence leading from glycogen storage foci through mixed cell foci and neoplastic nodules to hepatocellular carcinomas. Biochemical microanalysis of dissected glycogen storage foci and mixed cell foci revealed that the foci composed exclusively of storage cells contained on an average 100% more glycogen than the normal liver tissue. The overall glycogen content of the mixed cell foci, which were composed of both glycogenotic and glycogen-poor basophilic cells, was not distinguishable from that of normal tissue.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Hepatocellular glycogenosis and related pattern of enzymatic changes during hepatocarcinogenesis. 659 71


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