Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0006826 (cancer)
 1,092,456 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We isolated an ether-resistant internal antigen and an ether-sensitive antigen previously described in relation to bovine leukemia virus infection. These two antigens have now been isolated by isoelectric focusing and concanavalin A affinity chromatography, respectively. The ether-resistant antigen exhibited isoelectric heterogeneity with a major peak at pH 7.2 and a minor peak at pH 6.2. Its molecular weight, estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), was 23,000 (p23), and it gave a sedimentation value of 2.3s. For material containing ether-sensitive antigen, analyzed by SDS-PAGE, protein staining revealed four components with molecular weights of 18,000, 25,000, 45,000, and 55,000. Two of these [45,000 (gp45) and 55,000 (gp55)] were stained by periodic acid-Schiff reagent. Isoelectric point and sedimentation value of the major glycoprotein (gp45) were pH 5.0 and 3.4s, respectively; no immunologic cross-reactivity was found between p23 and glycoprotein antigen.
J Natl Cancer Inst 1976 Sep
PMID:Properties of two isolated antigens associated with bovine leukemia virus infection. 1 Apr 47

The profiles of 4 acute-phase reactant proteins (APRPs) (haptoglobin (HPT), alpha1 antitrypsin (AAT), alpha1 acid glycoprotein (AGP) and prealbumin (PALB)) have been studied during the evolution of bowel cancer. Serial measurements of these APRPs can add to the information obtained from measurements of the level of CEA and hepatic enzymes during the monitoring of postoperative patients. There is considerable stability in the profile in a given individual in health, Rises of AAT and AGP are associated with metastases. High levels of HPT may suggest involvement of the bowel wall by recurrent cancer. PALB levels tend to reflect the nutritional status. A discriminant function based on the log CEA, AAT and AGP preoperative blood levels can considerably improve on the predictive value attained using CEA levels alone.
Br J Cancer 1977 Feb
PMID:Acute-phase reactant protein profiles: an aid to monitoring large bowel cancer by CEA and serum enzymes. 1 5

An enzyme that hydrolyzes the O-glycosidic linkage between alpha-N-acetyl-D-galactosamine and serine or threonine in mucins and mucin-type glycoproteins was purified by chromatography on an Affi-Gel 202 column or isoelectric focusing from filtrates of Diplococcus pneumoniae cultures. The final preparations were free of protease and a wide range of other glycosidase activities. The preparation obtained by isoelectric focusing was shown to consist of a single protein by gel filtration and sodium dodecyl sulfate-gel electrophoresis. This preparation had an apparent molecular weight of about 160,000, determined by gel filtration, an optimum pH of 7.6, and an isoelectric point in the range pH 8 to 9. The enzyme releases the disaccharide Gal-GalNAc from a variety of glycopeptide and glycoprotein substrates and appears to have a specific requirement for an unsubstituted galactose in the nonreducing terminus and an alpha linkage between N-acetylgalactosamine and the aglycone. This is the only endoenzyme known capable of cleaving the linkage between a carbohydrate and serine or threonine residues in glycoproteins. The ability of this enzyme to act on macromolecular substrates and its pH optimum makes it ideally suited to explore the distribution and function of mucin-type glycoproteins on normal and cancer cell surfaces.
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PMID:Purification and properties of an endo-alpha-N-acetyl-D-galactosaminidase from Diplococcus pneumoniae. 2 77

Rabbits were immunized with extracts of primary or grafted intestinal adeno-carcinomas induced by carcinogenic drugs in inbred rats. After absorption with normal tissue extracts, the antisera were able to recognize three tumor-associated antigens. Two of them were glycoproteins, present in cancer cells but also, in trace amounts, in mucous cells of the normal digestive tract. The third antigen is not detectable in the normal digestive system, but present in normal spleen; on im-unofluorescence, it is not located in the cancer cells, but in polymorphonuclear cells infiltrating the tumor. None of the three antigens cross-reacts with human carcinoembryonic antigen, or human or rat alphafetoprotein. On the other hand, one of the glycoprotein antigens is immunologically related to the human blood group A substance.
Int J Cancer 1975 Jan 15
PMID:Antigens associated with chemically induced intestinal carcinomas of rats. 4 40

Plasma and prostatic fluid from man, dog, and baboon were measured for carcinoembryonic antigen (CEA) by a radioimmunoassay technique. No CEA was detected in plasma, prostatic fluid, or seminal fluid in 12 dogs and three baboons. Elevated CEA (less than 2.5 ng/ml) was found in 13 of 20 human prostatic fluids. It was inferred that there was no immunologic cross-reactivity of CEA among man, dog, and baboon. CEA has been isolated and purified from liver tumors. Biochemical studies reveal that CEA consists of 60 percent carbohydrate and 40 percent protein. It contains the following carbohydrates: fucose, mannose, galactose, sialic acid, N-acetylglucosamine, and a small amount of N-acetylgalactosamine. The following amino acids were found in CEA: lysine, histidine, arginine, aspartic acid, threonine, serine, glutamic acid, proline, glycine, alanine, valine, emthionine, isoleucine, leucine, tyrosine, phenylalanine, and cysteine. The amino acid sequence (first 30 amino acids) of the N-terminal has been determined. The N-terminal amino acid was lysine. Using this study as a model, other tumor antigens from prostatic tumor tissues are being investigated. The acid phosphatase isoenzyme from prostatic tissue was also studied. After a series of purifications, two chromatographic fractions were obtained. Treatment with neuraminidase removed the sialic acid content of the molecule, changed the isoelectric focusing patterns, and abolished the chromatographic heterogeneity. Sedimentation studies indicated a molecular weight of about 100,000. Biochemical studies showed that prostatic acid phosphatase isoenzyme is a glycoprotein which consists of 7 percent carbohydrate and 93 percent protein. It contains fucose, galactose, mannose, sialic acid, N-acetylglucosamine, and the following amino acids: aspartic acid, threonine, serine, glutamic acid, proline, glycine, alanine, valine, methionine, isoleucine, leucine, tyrosine, phenylalanine, lysine, histidine, arginine, tryptophan, and cysteine. An antiserum to this purified prostatic acid phosphatase isoenzyme is being prepared in animals.
Cancer Chemother Rep
PMID:Tumor antigen and acid phosphatase isoenzyme in prostatic cancer. 4 19

The carcinoembryonic antigen (CEA) active glycoproteins from perchloric acid extract of liver-metastasized primary colon tumor have been separated by concanavalin A Sepharose (Con A Sepharose) chromatography. The CEA activities separated by Con A Sepharose chromatography were designated as loosely bound and tightly bound which, respectively, eluted on the Con A Sepharose column between 0.12 and 0.15 M and 0.3 M alpha-methylmannose in a linear gradient of alpha-methylmannose. Further purification of these activities by Sephadex G-200, Bio-Gels A-1.5m and P-300 yielded two variants of glycoproteins (B1 and C2) with CEA activity. Both purified preparations of CEA had similar immunochemical properties. Their A280/A260 ratios were 1.30 and 1.56, respectively. The purified loosely bound CEA (B1) had immunological, chromatographic, and electrophoretic properties similar to those of 125I-CEA, whereas the tightly bound CEA (C2) had a lower molecular weight (120,000 to 140,000). Further, specificity to these two CEA's was established by their reactions in immunoelectrophoresis with preparations of specific goat anti-CEA anti-serum obtained from other investigators. The results indicate the practical use of Con A Sepharose affinity chromatography for the separation and characterization of glycoprotein tumor antigens.
Cancer Res 1975 Nov
PMID:Demonstration of two molecular variants of carcinoembryonic antigen by concanavalin A sepharose affinity chromatography. 5 2

The distributions of acid alpha1-glycoprotein, alpha1-fetoprotein, beta-galactosidase and gastrin in gastric carcinoma and gastric ulcer as well as in the neighbourhood of these lesions were studied by means of immunohistochemical methods on imprint preparation. We could not find significant differences between gastric carcinoma and the nonneoplastic lesions, except for the acid alpha1-glycoprotein. The results of this first study indicate that the immunochemical and immunohistological assay of acid alpha1-glycoprotein might be of practical value in diagnosing malignant changes of gastric mucosa.
Z Krebsforsch Klin Onkol Cancer Res Clin Oncol 1975 Sep 22
PMID:[Immunohistochemical studies on non neoplastic and neoplastic gastric mucosa. Determination of embryonic and specific antigens (author's transl)]. 5 51

Carcinoembryonic antigen (CEA) has been shown to contain no free cysteine thiol groups but 6 cystine disulphide bonds. 5'5-Dithiobis-(2-nitrobenzoic acid) (DTNB) will react with CEA only after reduction of the disulphide bonds with dithioerythritol. Reduction-alkylation of CEA using dithioerythritol and bromo-[1-14C] acetic acid confirmed the presence of 6 disulphide bonds, as did oxidation of the glycoprotein with performic acid. The products from the DTNB and reduction-alkylation treatments of CEA had less capacity to inhibit the binding of [125I]-CEA to anti-CEA in a radioimmunoassay than the original CEA but could, in sufficient quantities, totally inhibit the binding. Removal, using mercaptoethanol, of the thiol blocking groups from the DTNB-treated CEA resulted in a 55% recovery of antigenic activity. The product from the performic acid oxidation could only inhibit approximately 50% of the binding. Treatment of CEA with 0.533M sodium periodate (NaIO4) greatly reduced its antigenic activity, presumably a result of the oxidative cleavage of the disulphide bonds. No loss in activity, however, was observed when 5.33mM NaIO4 was used, and one Smith degradation (i.e. treatment in sequence with periodate, borohydride and mild acid) of CEA removed approximately 50% of the carbohydrate, including all of the fucose, sialic acid and 2-acetamido-2-deoxygalactose but did not change the antigenic activity.
Br J Cancer 1975 Dec
PMID:Studies on the structure and immunological activity of carcinoembryonic antigen - the role of disulphide bonds. 5 86

The previously described glycoprotein that promotes tumour cell aggregation, derived from rat ascites hepatoma cells and capable of partial purification by chromatography, was found to be a mixture of 2 factors with different antigenic property. One was not absorbed by immunoadsorbent chromatography with anti-rat serum antibody and the other was. The action of the unabsorbed factor was clearly more potent than that of the absorbed factor. Both the factors were found in the serum of tumour bearing rats and the action of the unabsorbed factor was also more potent than that of the absorbed factor; its amount increased with time after i.p. inoculation of the cells. The serum of healthy rats contained the absorbed factor but not the unabsorbed factor. It was thus assumed that the unabsorbed factor was associated with the hepatoma cell surface itself and released into the serum, while the absorbed factor was associated with serum protein coating the cell.
Br J Cancer 1976 Jan
PMID:Characterization of tumour cell aggregation promoting factor from rat ascites hepatoma cells: Separation of two factors with different antigenic property. 5 93

Prospects for the development of vaccines against herpes simplex virus types 1 and 2 and other herpesvirus group vaccines are discussed from the scientific, medical, and economic standpoints. Probably, the most practical development will be glycoprotein subunit vaccines, prepared from herpes simples virus types 1 and 2, that will be tested for prophylaxis and therapy of acute viral disease and for cancer that may be caused by these agents.
Cancer Res 1976 Feb
PMID:Herpes simplex vaccines. 5 28


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