Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0272170 (SDS)
 50,377 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have compared by SDS-PAGE Western blotting the molecules detected by two human monoclonal antibodies, C-OU1 and 16.88. The antibodies have previously been shown to detect a cytoplasmatic antigen with an Mr of 43 kD present in colon adenocarcinoma cell lines and in colon cancer tissues. We now demonstrate that these antibodies differ significantly in their fine specificity, resulting in a quite dissimilar tumor selectivity. The antibody 16.88, in addition to reactivity with the 43-kD molecule, also recognizes a 190-kD molecule present both in melanoma cells and in cells previously reported as 16.88 antigen positive. The 16.88 antibody does not detect a 43-kD molecule in extracts of melanoma cells. The 190-kD component was not detectable in hepatoma or mamma carcinoma cells, both of which showed presence of the 43-kD molecule. The C-OU1 antibody shows no reactivity with the 190-kD molecule in any of the cells tested or with other proteins in melanoma cells. Radiolabeled 16.88 antibody shows better localization to melanoma cancer than to colon cancer xenograft transplanted onto nude mice. These findings indicate the presence of a tumor-associated antigen not previously described and have obvious implications for potential clinical uses of the antibodies.
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PMID:Antigens recognized by two human monoclonal IgM anticolon cancer antibodies, 16.88 and C-OU1 (B9165). 175 84

The growth promoting effect of several hormones and growth factors on two human colon tumor cell lines (Caco-2 and SW 48) was studied using six different chemically defined serum-free media (SFM). Caco-2 grew in a simple SFM [GF3: Chee's Essential Medium (CEM) plus insulin, transferrin and selenium], whereas, SW 48 cells did not grow in GF3 medium. This suggested that Caco-2 cells probably secrete proteins in SFM which influence attachment and growth of Caco-2 and other tumor cells. Lyophilized Caco-2 conditioned medium and substratum, when added to plain CEM, supported growth of SW 48 and SW 948 cells. The substratum material was more effective than conditioned medium in promoting growth of the cell lines. The substratum material helps attachment and spreading of the cells and, thus, improves growth of the cells over conditioned medium. Caco-2 conditioned medium and substratum were analyzed for their components using SDS-PAGE system and gel filtration chromatography. The substratum was analyzed for the presence of fibronectin and laminin by the ELISA technique. The conditioned medium does not contain TGF alpha and TGF beta. The growth stimulating activity of the conditioned medium is due to a protein component, approximately 58Kd in size.
Cancer Biochem Biophys 1991 Aug
PMID:Proteins secreted by Caco-2 cells support growth of other tumor cells in Chee's Essential Medium without supplements. 176 10

The endocytosis and intracellular metabolism of radiolabeled anti-CD3 MoAb 64.1 by the malignant human T cell line HPB-ALL were studied using biochemical, morphological, electrophoretic, and chromatographic techniques. Biosynthetically labeled [3H]64.1 and externally radioiodinated 125I-64.1 were similarly internalized and degraded by tumor cells, with approximately 70% of the initially bound radioactivity being released to the culture supernatant as trichloroacetic acid-soluble radioactivity in the first 24 hr of culture. Radiolabeled 64.1 was routed from the cell membrane to endosomes where initial proteolysis began and finally to lysosomes where terminal catabolism to single amino acids occurred. SDS-PAGE demonstrated four major intracellular metabolite species (46, 25, 15, and less than 10 kDa). Thin-layer chromatography demonstrated that greater than 95% of the trichloroacetic acid-soluble radioactivity in culture supernatants was 125I-monoiodotyrosine, indicating that proteases, not deiodinases, were of primary importance in catabolism of 125I-64.1. In the presence of inhibitors of lysosomal function (leupeptin, monensin, and ammonium chloride), 125I-64.1 degradation was impeded, causing prolonged retention of radioactivity in the lysosomal compartment of cells. However, although the pace of catabolism was markedly diminished by these agents, no major changes in the sizes of intermediate metabolites generated were observed. Our results suggest that judicious administration of lysosomal inhibitors (e.g. chloroquine, verapamil, monensin) may significantly enhance retention of radioimmunoconjugates by lymphoid malignancies, improving radioimmunoscintigraphic and radioimmunotherapeutic efforts.
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PMID:Intracellular catabolism of radiolabeled anti-CD3 antibodies by leukemic T cells. 183 89

The serine/threonine O-linked carbohydrates GalNAc alpha and Gal beta 1-3GalNAc alpha, referred to as Tn and T antigens, respectively, appear to be more prevalent in some human carcinomas than in surrounding tissues. Tn/T antigens may represent incomplete synthesis of O-linked oligosaccharides, due to decreased activity of specific glycosyltransferases, or alternatively, increased glycosidases activity in tumors which may expose these internal O-linked oligosaccharide sequences. To explore these possibilities, we measured UDP-Gal:GalNAc alpha-R beta 1-3 galactosyltransferase (beta 3Gal-T) and Gal beta 1-3GalNAc alpha-R beta 1-3 galactosidase in a series of human breast tumors. In addition, glycoproteins extracted from the tumors were separated by SDS-PAGE and stained with the lectins HPA (GalNAc alpha-R reactive) and PNA (Gal beta-3GalNAc alpha-R reactive). The relative levels of HPA- to PNA-reactive glycoproteins in the carcinomas correlated inversely with beta 3Gal-T activities. The results suggest that Tn antigen expression in human breast carcinoma is due in part to low beta 3Gal-T activity, a situation similar to that observed previously in haematopoietic cells of individuals with a condition called Tn syndrome.
Cancer Biochem Biophys 1991 Nov
PMID:Tn antigen and UDP-Gal:GalNAc alpha-R beta 1-3Galactosyltransferase expression in human breast carcinoma. 184 11

A soluble (cell-free) oncofetal antigen (OFA) was detected in murine and human amniotic fluids by immunostaining with the murine monoclonal antibody (MAb 115) produced by syngeneic immunization with mid-gestational mouse fetal cells. OFA was purified from the amniotic fluids by ammonium sulfate precipitation at 30-70% saturation, followed by successive gel chromatography of the OFA-containing fraction on Sephacryl-S300 HR, Q- and S-Sepharoses and lentil lectin agarose. The fraction eluted from the lentil lectin column gave a single band on SDS-PAGE of the same molecular weight as the membrane-bound OFA found on both fetal and tumor tissues of humans and several rodents. Both soluble and membrane-bound OFAs share several chemical characteristics, including binding to lentil lectin and wheat-germ agglutinin, molecular weight (44 kDa) and pI (6.8). Mild periodate oxidation of OFA did not affect its binding to MAb 115 in an enzyme-linked immunosorbent assay, indicating that the reactive epitope is a peptide.
Int J Cancer 1991 May 10
PMID:Isolation and partial characterization of a soluble oncofetal antigen from murine and human amniotic fluids. 185 Mar 86

Patients treated with high doses of interleukin-2 (IL-2) because of cancer, develop hemodynamic and vasopermeability changes, that resemble those observed in sepsis. These patients thus provide a unique opportunity to study the early events in the development of septic shock. We analysed the changes that occurred in the contact system of coagulation in plasma from 4 patients, who together received seven 12-day cycles of high doses of IL-2. Levels of factor XII and prekallikrein during the cycles progressively fell to 50 and 30% of their initial levels, respectively, whereas significant increases in plasma factor XIIa- and kallikrein-C1-inhibitor complexes were not observed (in 3 out of 211 samples slightly increased levels of both complexes were found). The reductions in factor XII and prekallikrein were only in part due to protein leakage, since levels were still significantly lower, i.e., 80 and 50%, respectively, when corrected for albumin decreases. Levels of high molecular weight kininogen (HMWK) also decreased during IL-2 therapy, however, this decrease paralleled that of albumin. SDS-PAGE analysis of plasma HMWK did not reveal increased cleavage of this protein. The reduction of factor XII and prekallikrein, corrected for protein leakage, significantly correlated with albumin levels and inversely with daily cumulative weight gain in the patients. Thus, we demonstrate that factor XII and prekallikrein decrease during IL-2 therapy. As these decreases, already observed after 1 day treatment, were disproportional to that of albumin, a negative acute phase reactant, and correlated with signs of the vascular leak syndrome, we favor the explanation that they reflected activation rather than a decreased synthesis of the contact system proteins.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Studies on the contact system of coagulation during therapy with high doses of recombinant IL-2: implications for septic shock. 187 10

Protein from hog which is recognized by human monoclonal antibody (HB4C5), generated from a patient with large cell lung carcinoma, was identified as carboxypeptidase A by comparison of the protein with carboxypeptidase A in enzymatic activity, immunologic reactivity, and amino acid sequence. Carboxypeptidase A activity was also found in human cancer tissue, and purified antigen from cancer tissue recognized by the antibody HB4C5 was reacted with rabbit anti-carboxypeptidase A serum, indicating that carboxypeptidase A is an antigen of HB4C5. Since large amounts of carboxypeptidase A can be obtained from porcine sources, a simple method for its purification was established. The fraction which was most reactive with HB4C5 was obtained from acetone powder of porcine pancreas by successive applications of water extraction, ammonium sulfate precipitation, trypsin treatment, and Mono Q column chromatography. Its apparent molecular weight was 40,000, according to SDS polyacrylamide gel electrophoresis. When the reactivity of IgG in sera with the purified carboxypeptidase A was measured, the detection rates for lung, ovary, larynx, uterus, and liver cancer were more than 50%, while the rates for stomach and breast cancer were around 30%, and pancreatic cancer, benign diseases, and normal controls were minimally detected.
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PMID:Serodiagnosis of cancer using porcine carboxypeptidase A as an animal antigen recognized by human monoclonal antibody HB4C5. 187 99

Flavone acetic acid (FAA) is a potentially useful anti-tumour agent which has been reported to induce changes in tumour vasculature, in particular loss of bloodflow. This led us to examine whether endothelium could be a cellular target of FAA action, with resultant modulation of cell-surface coagulant properties leading to activation of coagulation and blockade of tumour blood flow. Incubation of endothelium with FAA led to the expression of functional tissue factor on the cell surface, in a time-dependent and dose-dependent (half-maximal at 0.6-0.7 mg/ml) manner. Induction of tissue-factor activity resulted from de novo translation of the tissue factor message. To explain the selectivity of FAA's action on tumour vasculature in vivo, we considered its interaction with tumour-derived factors. Starting with serum-free FO-I-melanoma cell-conditioned medium, a co-factor enhancing FAA-mediated induction of endothelial tissue factor (FO-I factor) was partially purified by sequential ion exchange and reverse phase chromatography, followed by preparative SDS-PAGE. The FO-I factor migrates with an apparent Mr of approx. 20 to 25,000 on non-reduced SDS-PAGE, is sensitive to protease K, and augments the effect of FAA on endothelial-cell-tissue factor. This activity is not found in supernatants from non-neoplastically transformed cell lines. These data lead us to hypothesize that FAA exerts its action, at least in part, by promoting activation of coagulation on the endothelial surface, and this effect is selective for the tumour bed by virtue of its interaction with a tumour-derived factor. The interaction of FAA with host factors may be important for optimizing its therapeutic efficacy for a particular tumour.
Int J Cancer 1991 Sep 09
PMID:Selective induction of endothelial cell tissue factor in the presence of a tumour-derived mediator: a potential mechanism of flavone acetic acid action in tumour vasculature. 187 70

Estrogen sulphotransferase plays a major role in controlling intracellular levels of 17 beta-estradiol in human mammary cancer cells and human endometrium. Bovine estrogen sulphotransferase c-DNA has recently been cloned; the encoded protein having a maximum Mr of 35,000 (Nash, A.R. et al. (1988) Aust. J. Biol. Sci. 41, 507-516). Enzyme of Mr 35,000 by SDS-PAGE has now been isolated and cyanogen bromide-cleaved peptides sequenced. The latter were identified in the c-DNA-predicted amino acid sequence which confirms that the active enzyme (Mr approximately 70,000) exists as a dimer of identical subunits. Sequence data on similar peptides isolated from an enzyme preparation containing a protein of Mr 74,000 as the major species on SDS-PAGE, which was previously thought to represent the enzyme, suggested that this protein was transferrin. This was confirmed by PAGE, SDS-PAGE, susceptibility to neuraminidase and reaction with bovine transferrin antibody. Isoelectric focusing experiments show that active enzyme exists in two or three polymorphic forms (pI values 5.3, 5.7 and possibly 5.9) having similar physicochemical properties of polymorphic forms of transferrin so that they overlap on ion-exchange chromatography and PAGE. The enzyme shows some homology to the amino acid sequence close to the Fe-binding site in lactoferrin and the question is raised as to the possible presence of a tightly bound metal in estrogen sulphotransferase involved in the binding of adenosine 3'-phosphate 5'-phosphosulphate.
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PMID:Enzymic synthesis of steroid sulphates. XVII. On the structure of bovine estrogen sulphotransferase. 190 Feb

A protein factor which stimulated [3H]thymidine uptake into free hepatocytes prepared from normal mouse liver was detected in the ascitic fluid of gynecological cancer patients. The factor was subsequently further purified from the ascitic fluid of an endometrial cancer patient by DEAE-Sephacel, Sephadex G-150 and Phenyl-Sepharose CL-4B column chromatographies, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed a single protein band of 54,000 Da, designated tentatively as 54K ascitic protein (54K-AP). 54K-AP was similar to human alpha 1-antitrypsin (alpha 1-AT) in terms of SDS-PAGE and immunological behavior, but was slightly different in terms of amino acid sequence and isoelectric point. Although 54K-AP inhibited the activities of bovine trypsin and alpha-chymotrypsin as did human alpha 1-AT, 54K-AP inhibited the plasminogen activator released from human endometrial cancer Ishikawa cells more efficiently than alpha 1-AT. Because, in contrast to normal serum, the serum from the endometrial cancer patients stimulated [3H]thymidine uptake into hepatocytes, the possibility arises that 54K-AP could be produced by the cancer host as a defence mechanism against the cancer.
Jpn J Cancer Res 1991 Jun
PMID:Characterization of a 54 kDa, alpha 1-antitrypsin-like protein isolated from ascitic fluid of an endometrial cancer patient. 190 55


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