sodium-dodecyl-sulfate and Nasopharyngeal-Neoplasms

The presence of an angiogenic protein basic fibroblast growth factor (FGF) was established in juvenile nasopharyngeal angiofibroma (JNF). Extracts of these tumors have the capacity to stimulate endothelial cell proliferation. This activity is indistinguishable from basic FGF. The biological activity contained in the extracts binds to heparin-Sepharose columns and is eluted with a characteristic 2 mol sodium chloride. The exact fraction of the biological activity corresponds to the location where an immunoreactive basic FGF can be detected by radioimmunoassay. These same fractions contain an 18,000-d molecule which is identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting with an antibody to basic FGF. Indeed, immunohistochemical studies localize the growth factor to the endothelium of JNF. Although these findings do not establish that basic FGF mediates the development of this angiofibroma, they do support the possibility that the pathogenesis of JNF is associated with the presence of angiogenic factors like basic FGF. If this is the case, a comprehensive study of the etiology of JNF may lead to a better understanding of how locally produced growth factors mediate proliferative disease and how its modification might lead to better treatment on a biological basis.

Topics: Adolescent; Adult; Blotting, Western; Cell Division; Cells, Cultured; Electrophoresis, Polyacrylamide Gel; Endothelium; Extracellular Matrix; Fibroblast Growth Factor 2; Fibroblasts; Histiocytoma, Benign Fibrous; Humans; Male; Nasopharyngeal Neoplasms; Radioimmunoassay; Sodium Dodecyl Sulfate

The urokinase-type plasminogen activator (uPA) activity in sera of patients suffering from nasopharyngeal carcinoma was examined by a uPA-specific immunocapture assay. The results revealed that the activity levels in the patient sera were significantly higher than that of normal healthy controls. The uPA activity also increased with the staging of the disease and the anti-EBV VCA IgA titre which is a diagnostic test for the disease, although the results were not statistically different. These findings showed that the levels of the enzyme were related to the spread of the disease. In addition, it was demonstrated that the sensitivity of the assay could be increased by using SDS. If the sera were treated with 0.2% sodium dodecyl sulphate (SDS) prior to the assay, higher levels of measureable PA activity were detected.

Topics: Antigens, Viral; Capsid; Fibrinolytic Agents; Fluorescent Antibody Technique; Herpesvirus 4, Human; Humans; Immunoglobulin A; Nasopharyngeal Neoplasms; Neoplasm Staging; Plasminogen Activators; Plasminogen Inactivators; Sodium Dodecyl Sulfate; Urokinase-Type Plasminogen Activator

1. A fraction enriched in plasma membranes of human tumour KB cell line, a permissive cell for adenovirus type 5, was obtained. 2. Electrophoresis of the membranes in polyacrylamide gels with buffers containing sodium dodecyl sulphate showed that the membranes after reduction with 2-mercaptoethanol contained over 20 polypeptide species. Three polypeptides were glycosylated and had apparent mol.wts. of 92000, 72000 and 62000. 3. The glycoproteins and the specific receptors responsible for adenovirus adsorption to the membranes were readily extracted into solutions containing low concentrations of Triton X-100. Glycolipids and proteins were also made soluble. A membranous residue obtained after Triton X-100 extraction was enriched in several proteins that appeared to consist of polypeptides of lower molecular weight than the average of KB membrane polypeptides. 4. Sphingomyelin, cholesterol and triglycerides were similarly concentrated in the insoluble residue remaining after successive extractions of KB membranes with Triton X-100. Further, ceramide trihexoside was significantly less easily extracted from KB membranes than lactosyl ceramide. 5. The differences noted in the ease of extraction of membrane components are discussed. 6. The components of membranes made soluble by detergent extraction and containing the large part of the KB membrane glycoproteins were subjected to chromatography on Sepharose 6B and DEAE-cellulose and to isoelectric focusing in the presence of buffers containing Triton X-100. In general, the degree of separation into fractions enriched in individual glycoproteins was disappointing. Possible reasons for the poor fractionation of membrane components by chromatographic systems conveniently used for purification of proteins and glycoproteins of non-membranous origin are briefly discussed.

Topics: Adenoviridae; Carbon Radioisotopes; Cell Line; Cell Membrane; Ceramides; Cholesterol; Chromatography, DEAE-Cellulose; Chromatography, Gel; Electrophoresis, Polyacrylamide Gel; Glycolipids; Glycoproteins; Humans; Mercaptoethanol; Microscopy, Electron; Molecular Weight; Nasopharyngeal Neoplasms; Sodium Dodecyl Sulfate; Sphingomyelins; Sulfur Radioisotopes; Surface-Active Agents; Triglycerides; Tritium