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 lectin present in the broad bean, Vicia faba, was isolated by affinity chromatography on Sephadex G-150. The active lectin had a molecular weight of 50 000. The lectin contained about 3% neutral sugar and it contained two different subunits. The subunits had molecular weights of 17 300 and 14 300. The lectin was mitogenic to human peripheral lymphocytes with some reduction in activity upon acetylation. The lectin competed with pea lectin for binding to murine tumor cells. Binding to tumor cells was inhibited by methyl-alpha-D-mannoside but not by D-galactose; binding was not influenced by the presence or absence of Ca2+, Mn2+ or ethylenediaminetetraacetate.
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PMID:Isolation and partial characterization of a lectin from Vicia faba. 82 78

An ovarian cystadenocarcinoma-associated antigen (OCAA) was found to be common to all serous and mucinous cystadenocarcinomas of the ovary. It was apparently absent in tissues of normal reproductive organs. Furthermore, OCAA was not detected in benign ovarian serous and mucinous cyst-adenomas or in any other gynecologic or nongynecologic cancers thus far tested. The antigenic determinant of OCAA was immunologically unrelated to the carcinoembryonic antigen, other known tumor antigens, or the histocompatibility antigens. We purified and partially characterized OCAA. The antigen was a high-molecular-weight glycoprotein soluble in 0.6 M perchloric acid. It consisted of about 50-60% protein (based on dry wt). Amino acid composition in OCAA was characterized by a high percentage of threonine, serine, proline, and valine. Galactose and N-acetylglucosamine were the principal carbohydrate constituents. The antigenic activity was resistant to treatment with trypsin and protease and also to treatment with DNase, RNase, and N-acetylneuraminidase. The antigenicity was considerably reduced by mild periodate oxidation.
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PMID:Tumor-associated antigen for cystadenocarcinomas of the ovary. 82 81

Two groups of patients suffering from advanced neoplastic disease were fed parenterally for a period ranging from 1 to 16 weeks. The parameters considered were: weight change, serum albumin level, lymphocyte transformation test and serum immunoglobulin level. There were 23 patients in one group and 21 patients in the other. Regimens included for group I: saline solution (1000-1500 ml), glucose (100-150 g) and amino acids (15-30 g) per day; for group 2: 40-50 Cal/kg per day (dextrose about 15 g/kg per day), about 2 g of amino acids/kg/day and about 40-50 ml water/kg/day. In addition, 13 patients underwent both treatments sequentially. All the Group I patients lost weight (1.3 kg/week); while out of 23 patients in Group 2, 15 gained weight, 2 remained unchanged and 6 continued to lose weight, but to a lesser rate than before hyperalimentation (the average weight gain was 1.1 kg/week). Serum albumin levels decreased in 19 out of 25 patients in Group I and increased in 14 out of 26 patients of Group 2. Initial values of the lymphocyte blast transformation test were very low in both groups of patients, and an increase was observed only in patients treated by hyperalimentation. The increase was more evident in patients who were not under antiblastic treatment. Changes in serum immunoglobulin levels were not significant. The authors conclude that malnutrition plays a very important role in neoplastic cachexia and can be improved by parenteral hyperalimentation. Although it is possible that in the near future hyperalimentation and conventional neoplastic therapies will play complementary roles in treatment of advanced neoplastic disease, malnutrition is still the specific indication for intravenous hyperalimentation.
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PMID:[Parenteral hyperalimentation in patients with advanced neoplastic disease (author's transl)]. 82 82

A new method of affinity chromatography using glutaraldehyde-fixed cells immobilized on Sephadex beads has been used to isolate immunoglobulins (Ig's) specific for cell surface glycoproteins. Ig's that specifically bound and agglutinated the same cells as those originally fixed on the columns were isolated from nonimmune sera of various species. Periodate treatment of the cell-columns and the free cells destroyed their ability to bind the Ig's, and the binding of the Ig's to untreated cells was inhibited by monosaccharides such as D-galactose and sialic acid. The binding of antibodies directed against cell surfaces obtained by immunizing animals with the same mouse tumor cell lines used on the columns (P388 and EL4) was not inhibited by various saccharides. Surface glycoproteins obtained from the mouse tumor cells by immunoprecipitation with the column-isolated Ig's yielded specific electrophoretic patterns that differed from those obtained using Ig's from the sera of rabbits immunized with the tumor cells. The data suggest that the Ig's isolated by cell-column chromatography were directed against carbohydrates, probably those in terminal positions of the polysaccharide portions of the tumor cell surface glycoproteins. Column-isolated Ig's specific for carbohydrates were also useful in studies of cell interactions in nonmammalian systems including Dictyostelium discoideum and Saccharomyces cerevisiae. The cell-column method appears to be adaptable to the isolation of a variety of molecules in addition to antibodies.
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PMID:Isolation by cell-column chromatography of immunoglobulins specific for cell surface carbohydrates. 83 47

In order to study the mechanism of tumor cell surface antigen shedding, galactosyltransferase levels were compared in 5 spontaneously metastasizing and 3 nonmetastasizing rat mammary tumors. The enzyme activity both with or without exogenous acceptors was higher in the metastasizing group. This difference did not seem to be due to the variation in levels of degrading enzymes such as pyrophosphatase or beta-galactosidase found in these tumors. Little difference in the biochemical properties of the enzyme was found between the two groups. Most of the enzyme activity (60-70%) was recivered in the microsomal frctosyltransferase was assayed in "purified" plasma membrane fractions, 70% of the activity was associated with the plasma membrane vesicles, in which the enzyme was enriched by factors of 10-40. The number of galactose acceptor sites on the plasma membranes increased in parallel to the metastasizing capacity, indicating the presence of larger numbers of incomplete glycopeptides on their cell surfaces. These findings seemed to indicate that the greater turnover of glycoprotein in the spontaneously metastasizing tumor cell surface was caused by the shedding of surface antigens into the systemic circulation of the host.
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PMID:Galactosyltransferase activity in metastasizing and nonmetastasizing rat mammary carcinomas and its possible relationship with tumor cell surface antigen shedding. 83 75

We have investigated the receptor site activity present on 6C3HED tumor cells for concanavalin A, fava, lentil and pea lectins. The binding of the tritiated lectins to the tumor cells was inhibited by methyl-alpha-D-mannoside but not by D-galactose. The number of binding sites for the lectins was 3.5-10(6)/cell for concanavalin A, 3.3-10(6)/cell for fava, 3.6-10(6)/cell for lentil and 4.8-10(6)/cell for pea. The apparent association constants were 3.6 and 1.3 muM-1 for concanavalin A, 3.9 muM-1 for fava, 4.2 muM-1 for lentil and 4.6 and 0.6 muM-1 for pea. Competitive inhibition studies showed that lentil was a good inhibitor of pea binding; concanavalin A was a poor inhibitor of pea binding; and fava was a better inhibitor than concanavalin A but not as good as lentil. Reciprocal inhibition experiments indicated that concanavalin A and pea may bind to different receptors as well as to common receptors. This was also indicated by the observation that trypsin or protease treatment of the cells decreased the binding of pea lectin by 20-40 percent whereas concanavalin A binding was unaffected.
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PMID:Studies on 6C3HED murine ascites tumor cell receptors for mannosyl-binding lectins. 95 11

Analysis of carcinoembryonic antigen (CE)-reactive glycoproteins from liver metastasis of primary colon and breast tumors and from primary breast tumors has been carried out by affinity chromatography on concanavalin A (Con A)-Sepharose. Three CEA-reactive glycoproteins from colon tumors (liver metastasis) with different binding capacity to Con A have been separated and further purified by gel filtration. Of the 3 CEA-reactive glycoproteins, 1 of them did not bind to Con A. Both Con A-binding and nonbinding CEA-reactive glycoproteins were immunologically indistinguishable when tested with a reference goat anti-CEA (ACE, 67-70; Dr. C.W. Todd and Dr. M.L. Egan), as well as with a variety of rabbit anti-CEA and anti-CEA (nonbinding) prepared in this laboratory. Carbohydrate analysis showed that mannose content of different purified CEA preparations or nonbinding CEA did not differ appreciably. N-Acetylglucosamine content of purified CEA preparations, however, varied considerably, suggesting that this sugar may impart the specificity of binding of CEA to Con A. The purified CEA preparations differed in their ability to inhibit the binding of 125l-labeled CEA to goat anti-CEA. One of the purified CEA preparations had 3- to 8-fold greater inhibitory capacity when compared to other preparations and shared a partial identity with a glycoprotein present in the extracts of fetal colon. The glycoprotein extracts of primary breast tumors did not contain a CEA that was immunologically identical to CEA present in colon tumors, whereas the liver metastasis of primary breast tumors showed several CEA-reactive glycoproteins as judged by radioimmunoassay. However, these CEA-reactive glycoproteins did not have any antigenic relationship with CEA from colon tumors when tested by double diffusion and immunoelectrophoresis. In conclusion, when Con A affinity chromatography of tumor glycoproteins is carried out under defined conditions and with the use of appropriate antisera, it is possible to delineate the presence or absence of CEA in tumors of nonentodermal origin.
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PMID:Immunochemical studies on carcinoembryonic antigen-reactive glycoproteins from carcinomas of the colon and breast separated by concanavalin A affinity chromatography. 97 8

Inhibition of repair of sublethal and potentially lethal damage was observed in respiratory-deficient mutants of yeast during fractionated X-irradiation in the presence of equimolar concentrations of 2-deoxy-D-glucose and glucose in the growth medium. In the wild-type cells, on the other hand, an enhancement of repair of the potentially lethal damage was obtained under similar conditions. These results suggest, by analogy, that in higher organisms also, 2-deoxy-D-glucose may differentially inhibit the repair of radiation damage in hypoxic tumor cells while enhancement of repair processes could be expected in normal tissues.
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PMID:Influence of energy metabolism on the repair of x-ray damage in living cells. IV. Effects of 2-deoxy-D-glucose on the repair phenomena during fractionated irradiation of yeast. 110 51

Glycosyltransferase enzymes were measured in homogenates of normal and neoplastic colon epithelium. The levels for exogenous galactosyltransferase and fucosyltransferase and endogenous N-acetylglucosaminyl-transferase were higher in the normal tissue. The levels for exogenous and endogenous sialyltransferase and endogenous galactosyltransferase and fucosyltransferase were comparable in the homogenates of normal and cancer cells. Incorporation of fucose and galactose into purified carcinoembryonic antigen (CEA), used as an exogenous acceptor by colon glycosyltransferases, was demonstrated by immunoprecipitation with rabbit antiserum to human CEA. The normal fucosyltransferase and galactosyltransferase showed higher activity with CEA than did the tumor enzymes.
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PMID:Alterations in glycosyltransferase activity in human colon cancer. 111 12

No tumor-specific tracer has yet been found for the detection of brain tumors by external scintiscanning. Glucose is a substrate in high demand by almost all tumors, and therefore an investigation was undertaken into the potential value of glucose and its analogs as tracers for brain tumors. The compounds studied were D-)1-3H)glucose, D-(1-14C)glucose, (3H)3-O-methyl-D-glucose and L-(1-14C)glucose. The tracers were injected i.v. into C57BL/6J mice carrying a transplantable s.c. ependymoblastoma. At specific time intervlas after injection, mice were sacrificed and the radioactivity of 6 tissues including tumor and brain were assayed by means of an automated combustion technique and liquid scintillation counting. Tumor uptake, expressed as percentage mean body concentration, was 60% for 2 of the tracers, and 92 and 143%, respectively, for 2 others. Brain uptake was over 130% mean body concentration, with 3 of the 4 tracers studies. With L-glucose, brain uptake was only 15.4% mean body concentration, and a maximum tumor-to-brain ratio of 9.5 was achieved. The very high tumor uptake achieved with two of these carbohydrated demonstrates that a carbohydrate analog may be found that shows high tumor specificity and uptake, and that may be useful for external scintiscanning.
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PMID:Glucose analogs as potential diagnostic tracers for brain tumors. 111 33


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