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)

Horseradish peroxidase (HRP) uptake was used to measure fluid-phase pinocytosis in monolayers of human epithelioid carcinoma cells (A-431). Histochemistry confirmed that cell-associated HRP was restricted to intracellular vesicles. Biochemical methods showed that HRP uptake in control cultures was directly proportional to the duration of exposure. The addition of low concentrations of epidermal growth factor (EGF) to the incubation media produced a 10-fold increase in the initial rate of pinocytosis. The EGF effect was rapid (within 30 s) but transient; the rate of pinocytosis returned to control levels within 15 min. Metabolic inhibitors reduced the EGF-stimulated rate of pinocytosis by greater than 90%. A conjugate of EGF and ferritin (F:EGF) was used to simultaneously compare the intracellular locations of EGF and HRP. Much of F:EGF was internalized in approximately 100-nm vesicles, while most of the HRP was located in much larger vesicles (range 0.1--1.2 micrometer) which also contained F:EGF. The tumor-promoter 12-0-tetradecanoyl-phorbol-13-acetate, which shares several biological activities with EGF, was also effective in stimulating an increase in the rate of pinocytosis.
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PMID:Rapid stimulation of pinocytosis in human carcinoma cells A-431 by epidermal growth factor. 31 44

Immunological and chemical studies of cell surfaces from normal and transformed BALB/c fibroblasts have shown alterations associated with transformation. The cells studied include normal lines which do not cause tumors when injected into BALB/c mice, viral transformants, and spontaneous transformants which cause tumors that either regress or grow progressively, killing the host. The spontaneously transformed progressors include cell lines which are immunogenic and nonimmunogenic as determined by the ability of tumor excision to protect an animal from subsequent rechallenge by tumor cells. Tumor-bearing mice produce lymphocytes which are nonspecifically cytotoxic for all the normal and transformed lines. Some of the cell lines induce specific antibody formation in BALB/hosts. Antisera have been prepared in rabbits which are specific for the transformed cell lines. These antisera can be used to determine specific surface changes on the transformed cells. Chemical studies have shown glycolipid alterations between the normal cells and some, but not all, of the transformants. Glycoproteins labeled by lactoperoxidase-125I or [3H] glucosamine were compared by SDS gel electrophoresis. Results from these studies do not show changes associated with malignancy. Individual glycoprotein regions from gels were treated with pronase, and the glycopeptides compared by Sephadex G50 chromatography. Alterations in glycopeptides from several cellular glycoproteins are the only changes which appear to be associated with malignancy.
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PMID:Chemical and immunological studies of cell surfaces from normal and transformed cells. 33 94

Several major defects in the estrogen receptor pathway have been evidenced in most human breast cancers by an immunofluorescence tracing of estradiol receptor complexes at the single cell level. Endogenous peroxidase seems a reliable postreceptor marker for estrogen-sensitive breast cancer cells. Since almost all human breast cancers appear to include both hormone-sensitive and autonomous cell populations, a combined use of endocrine and cytotoxic regimens is urged. The hormonal regulation of tumor growth parameters could be exploited in order to achieve a maximum recruitment of synchronized tumor cells at risk to chemotherapy.
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PMID:Estrogen receptors and post-receptor markers in human breast cancer: a reappraisal. 35 48

The presence of choriogonadotropin-like material and its intimate association with the membranes of the wall of bacteria isolated from cancer patients, has been demonstrated by immuno-electron microscopy utilizing the indirect peroxidase-antiperoxidase-labeled antibody technique. The bacteria were an Escherichia coli strain isolated from a carcinoma of colon, and ATCC 25559 strain of Eubacterium lentum, an anaerobic microorganism originally isolated from a rectal tumor.
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PMID:Immuno-electron microscopic localization of a choriogonadotropin-like antigen in cancer-associated bacteria. 38 8

The fate of lectin labeled internalized plasma membrane in the ascites tumor form of the Chang rat hepatoma growing under in vivo and in vitro conditions was investigated cytochemically. Ascites cells were incubated in Convanavalin A (Con A) and horseradish peroxidase (PO), either with or without prior glutaraldehyde fixation and subsequently treated with 3',3-diaminobenzidine. In cells fixed before Con-A-PO labeling the reaction product was localized as a continuous and even layer upon the external surface of the plasma membrane. If unfixed cells were treated with Con A, coupled with PO at 4 degrees C and reincubated in phosphate buffered saline at 37 degrees C for varying periods of time, the Con-A-PO layer was of irregular thickness. In as little as 15 min of reincubation endocytotic vesicles containing PO positive material were closely associated with GERL components of the Golgi Apparatus. Localization of acid phosphatase (ACPase) within GERL vesicles, similar in size and location to those containing Con-A-PO reaction product, indicates that the Con-A-PO labeled vesicles may be a component of the Golgi apparatus in hepatoma cells.
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PMID:Cytochemical localization of lectin labeled vesicles in GERL region of hepatoma ascites cells. 38 67

A method for the localization of pyruvate kinase isoenzymes type L, M2 and M1 in tissue sections is described. Mono-specific antibodies directed against isoenzymes of pyruvate kinase from chicken and the peroxidase antiperoxidase method were used. The following preferential localizations of the isoenzymes in chicken tissues were observed: Pyruvate kinase M1 was found in skeletal muscle. The white muscle fibers were more intensely stained than the red. Some dark muscles (e.g., anterior latissimus dorsi) and the heart muscle showed no reaction with antiserum against pyruvate kinase M1. Pyruvate kinase type L was found in the hepatocytes and in kidney cortex. Pyruvate kinase type M2 was seen in the distal tubules of kidney, in hepatocytes and sinusoidal cells in liver, in lung, adipose tissue, and in the spleen mainly in the bursa dependent areas. Pyruvate kinase type M2 was detected in high concentrations in the granulation tissue of regenerating liver after partial hepatectomy. Liver sections of a hen bearing a pancreatic tumor showed an unusually high content of pyruvate kinase type M2 in some hepatocytes, which were each clustered to spots in the liver parenchyma. Thus, contrary to previous reports, the tissue distribution of isoenzymes in chicken is similar to that of other vertebrates.
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PMID:Immunohistochemical localization of pyruvate kinase isoenzymes in chicken tissues. 39 63

We have compared cell surface proteins and glycoproteins from normal and transformed cells by two-dimensional electrophoresis. The tumor lines studied include viral and spontaneous transformants which cause tumors that either regress, or grow progressively and kill the host. After the cells were labeled, crude membranes were prepared, and their protein components were resolved by two-dimensional electrophoresis. Cells were labeled with either [35S]methionine, [14C]glucosamine, or 125I-lactoperoxidase. This allows comparison of cell-cell differences in surface structure as well as membrane proteins and glycoproteins. We have demonstrated that not all transformed cell lines give a characteristic "transformed" protein pattern. Many of the differences between the normal and transformed cell protein patterns may be related to alterations in the carbohydrate of membrane glycoproteins. A correlation can be made between the patterns obtained for cell lines and the immunogenicity and tumorigenicity of these cells in vivo.
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PMID:Two-dimensional electrophoresis of membrane proteins from normal and transformed cells. 44 61

In 24 men aged 32 to 58 years with precancerous states of the larynx, i.e., leukoplakia, papillomas and pachydermia the peripheral blood lymphocytes were cytochemically stained for N-acetyl-beta-glucosaminidase, beta-glucuronidase, acid phosphatase and glycogen; and the neutrophils were stained for alkaline phosphatase, myeloperoxidase and lipids. The results were expressed in terms of the absolute counts of reaction-positive cells and of the activity index score. The serum immunoglobulins IgG, IgA and IgM were also determined by Mancini's method. The results obtained were compared with those in 20 healthy men aged 20 to 30 years. The patients exhibited elevated numbers of N-acetyl-beta-glucosaminidase and beta-glucuronidase-positive lymphocytes. A characteristic feature was an increase in the absolute counts of lymphocytes with diffuse and granular-diffuse types of cytochemical reaction for all enzymes studied. The number of cells with the granular type of enzymatic reaction (intact enzyme-positive lysosomes) was significantly diminished. These cytochemical alterations were accompanied by a significant increase in the serum IgA level. These results are discussed with reference to the lymphoid system response to tissues of precancerous lesions of the larynx. So far as the neutrophils are concerned the patients exhibited significant intracellular deficiency of beta-glucuronidase and decrease in the lipid content as well as an elevated alkaline phosphatase activity. The possible significance of the beta-glucuronidase deficiency in neutrophils for the diminished cytotoxic response of these cells against the tumor and precancerous lesion cells is discussed.
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PMID:Lymphocytes, neutrophils and serum immunoglobulins in patients with precancerous states of the larynx. 44 57

Using the indirect fluorescein-labeled and indirect peroxidase-antiperoxidase-labeled immunohistochemical techniques, and utilizing both antiserum specific for the beta-subunit of choriogonadotropin and antiserum for the total hormone, we have demonstrated the presence of a choriogonadotropin-like immunoreactive material in a strain of Eubacterium lenthum that was originally isolated from a rectal tumor. In contrast, both immunohistochemical reactions were negative when applied to a strain of Corynebacterium parvum and to pathogenic and nonpathogenic strains of Agrobacterium tumefaciens. Our results demonstrate for the first time the expression of the choriogonadotropin-like antigen in an obligate anaerobe and support our previous findings that the choriogonadotropin like material appears to be expressed only in "cancer-associated bacteria" but that not all bacteria associated with the malignant neoplasms have the capacity to express the antigen, at least in amounts detectable by immunohistochemistry.
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PMID:Choriogonadotropin-like antigen in an anaerobic bacterium, Eubacterium lentum, isolated from a rectal tumor. 46 80

A method whereby lactoperoxidase-catalyzed 125I-iodination of plasma membrane lipids can be achieved is described. The reaction results in a uniform and stable labeling of neutral lipids, phospholipids, lysophosphatides, free fatty acids, and triacylglycerides. By the use of this method, the action of antibody plus complement (C) on the specific release of lipid from the plasma membrane of line-10 tumor cells was studied. Within 15 min after the addition of C to antibody-sensitized cells, the enhanced release of specific lipid classes from the cell surface was observed; these lipids included sphingomyelin, phosphatidylserine, and phosphatidylcholine. The release of phosphatidylethanolamine and, in some instances, triglycerides, was reduced after antibody-C attack. Neither the specificity of the antibody used to sensitize the cells nor the ability of the antibody plus C to be cytotoxic to the cells appeared to affect the identity or amounts of lipids released from the cells.
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PMID:Specific 125I-iodination of cell surface lipids: plasma membrane alterations induced during humoral immune attack. 48 73


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