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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Many glioma-derived cell lines have the capability of escaping cell-mediated immune attack. One mechanism of escape is the secretion of a hyaluronidase-sensitive mucopolysaccharide coat by these cells. This coat prevents contact and tumor cell killing by specific cytolytic allogeneic lymphocytes. The production of the coat by the tumor cells is stimulated by a macromolecular factor released by peripheral blood mononuclear (PBMC) cells in culture. We have examined the morphologic and ultrastructural features of this extracellular matrix. Three coat-producing lines were studied. Under phase contrast light microscopy, the coat is a clear pericellular 'halo'. To stain this zone, ruthenium red and Alcian Blue 8 G stains, which bind to acid mucopolysaccharides (to a large extent, hyaluronic acid), were used. The two stains produced similar results. With light microscopy, a weblike pattern of stain was evident throughout the halo region. With transmission electron microscopy, staining was found along the plasma membrane of the glioma cells and their microvilli, stretching in long, branching filaments from these surfaces and, in some instances, from one microvillus to the next. Since mucopolysaccharide matrices have a large aqueous component, it was necessary to determine whether dehydration alters the stain pattern. Therefore, undehydrated ruthenium red stained specimens from each culture were embedded in Quetal 651 (Ted Pella, Inc., Tustin, CA), a water soluble plastic. No morphologic differences were noted between the hydrated and dehydrated specimens. This study indicates that numerous long microvilli and a secreted mucopolysaccharide matrix are important structural elements of the lymphocyte-stimulated tumor cell halo in vitro. The mechanism by which the PBMC factor stimulates coat formation and the importance of the coat in in vivo tumor defenses remain to be elucidated.
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PMID:Ultrastructural features of the lymphocyte-stimulated halos produced by human glioma-derived cells in vitro. 242 Sep 43

A hyaluronidase-sensitive component of human peritoneal fluid from a patient with Wilms' tumor when injected into rabbits has been shown to suppress the formation of humoral precipitating antibodies to certain major classes of proteins present in the fluid. Furthermore, it has been found that hyaluronic acid, when included with certain test antigens (serum albumin, fetuin) or antigen mixtures (tumor isolates or mixtures of albumin, immunoglobulin G and immunoglobulin M), produces a marked distortion or complete blockage of immunoelectrophoresis precipitin arcs, as well as altered gel chromatography elution profiles. These findings that hyaluronic acid can interfere profoundly with both the elicitation of a complete antibody response and the formation of "normal" patterns of antigen-antibody precipitates in laboratory tests supports the possibility that this polysaccharide may play an immuno-regulatory role by masking potential immunogens. Consideration of the mechanisms for these in vivo and in vitro effects suggests that there may be some common basis in an "excluded volume" property of the hyaluronate, but this does not appear sufficient to explain the complexity and selectivity of the observed phenomena.
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PMID:The selective suppression of immunogenicity by hyaluronic acid. 242 4

Cytotactin is an extracellular matrix protein that is involved in neuron-glia adhesion and is found in both neural and nonneural sites. It is synthesized by glia but not by neurons. In this study, we have examined the binding of cytotactin to a variety of extracellular matrix components using uniform microscopic beads (Covaspheres) that could be labeled and then linked to purified molecules. Cytotactin-coated beads bound well to neurons, and this binding was strongly inhibited by anti-cytotactin antibodies but not by anti-neural cell adhesion molecule (anti-N-CAM) antibodies. In contrast, the binding of N-CAM-coated beads to neurons was inhibited by anti-N-CAM antibodies and not by anti-cytotactin antibodies. To identify a neuronal ligand for cytotactin, we tested several molecules for their ability to block the binding of cytotactin-coated beads to cells. A proteoglycan-containing fraction that copurified with cytotactin from brain extracts strongly inhibited binding, whereas neither a heparan sulfate proteoglycan from Engelbreth-Holm-Swarm tumor cells nor soluble cytotactin itself had a significant inhibitory effect. The neural proteoglycan also inhibited the binding of cytotactin-coated beads to fibroblasts. Digestion with chondroitinase, heparitinase, and hyaluronidase as well as immunological analyses suggested that the predominant species in the active fraction was a chondroitin sulfate proteoglycan with a Mr280,000 core protein bearing HNK-1 antigenic determinants and also indicated that hyaluronic acid was present in this fraction. In experiments on in vitro synthesis, it was found that the proteoglycan was synthesized in culture by embryonic chicken brain tissue but not by embryonic chicken glial cells. A series of binding experiments was performed on appropriately derivatized beads to confirm that the proteoglycan is a ligand for cytotactin and to check for the possibility that other extracellular matrix proteins might interact with one or the other member of this binding couple. Proteoglycan-coated beads and cytotactin-coated beads coaggregated readily. The aggregation was inhibitable by anti-cytotactin antibodies, soluble cytotactin, or soluble proteoglycan. Addition of laminin inhibited the binding of cytotactin-coated beads to proteoglycan-coated beads or to cells; this is consistent with data indicating that laminin interacts with a component of the proteoglycan-containing fraction. In contrast, fibronectin bound to cytotactin, but it did not bind to proteoglycan or interfere with the binding of cytotactin to proteoglycan. The results of this study are in accord with the idea that the functions of extracellular matrix components during neural and nonneural development may be modulated both by competition for shared cell surface receptors and by a network of molecular interactions among the matrix components themselves.
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PMID:A proteoglycan with HNK-1 antigenic determinants is a neuron-associated ligand for cytotactin. 243 34

A mesothelial, endothelial and epithelial differentiation of the adenomatoid tumors is discussed in the literature. Aimed at this problem the cellular nature of 12 adenomatoid tumors was investigated by means of histochemical and immunohistochemical methods at light and electron microscopic level. In all these neoplasias prekeratin was demonstrated while factor VIII-associated antigen and myoglobin were lacking within the tumor cells. The ultrastructural picture of the tumor cells was similar to that of mesothelial cells; abundant intermediate filaments of the keratin type could be decorated by means of the protein A-gold technique in them. Furthermore hyaluronidase sensitive glycosaminoglycans but no sulfated and neutral mucoproteins were found. The results suggest a mesothelial nature of the tumor cells of adenomatoid tumors.
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PMID:Adenomatoid tumors--mesotheliomas or not? A histochemical, immunohistochemical and light and electron microscopic (TEM/SEM) study. 243 54

A rare case of adenomatoid tumor arising in the ovary is presented. At autopsy on a 61-year-old woman, a soft, solid and cystic tumor, measuring 0.8 X 0.7 cm, was detected in the hilus of the left ovary. Light microscopic study showed characteristic features of adenomatoid tumor. Alcian blue stain, with and without hyaluronidase pretreatment, revealed the presence of hyaluronic acid on the luminal surface and in the vacuoles of the tumor cells. Immunohistochemical stains of tumor cells were positive for low-molecular-weight cytokeratin (PKKL), vimentin, and carbohydrate antigen (CA) 125, whereas they were focally positive for high-molecular-weight cytokeratin (34 beta E12). They were negative for factor VIII-related antigen (FVIII-RAG), Ulex europaeus I lectin (UEA I), carcinoembryonic antigen (CEA) and epithelial membrane antigen (EMA). Ultrastructural studies disclosed surface microvilli and bundles of tonofilaments. These observations strongly support the idea of this tumor being of mesothelial origin.
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PMID:Adenomatoid tumor of the ovary: an immunohistochemical and ultrastructural study. 245 35

In order to clarify the biological characteristics of rat mammary tumors induced by 7,12-dimethylbenz-[a]-anthracene (DMBA), histochemical and immunohistochemical studies were performed. Two types of luminal spaces were observed within the tumor. In one type, the lumen was surrounded by eosinophilic columnar cells which were strongly reactive for soybean agglutinin (SBA) but weakly stained with keratin antibodies. In the luminal spaces, substances positive for PAS, dialyzed iron ferrocyanide or alcian blue and resistant to mucopolysaccharidase were occasionally observed. Ultrastructurally, the luminal surface was characterized by the presence of microvilli and tight junctions. In the other type, the lumen was often found in highly cellular foci and surrounded by pale, polygonal or elongated cells which were weakly stained with keratin antibodies but not SBA. The luminal spaces presented a peculiar structure filled mainly with mucoid substances sensitive to hyaluronidase, chondroitinase ABC and heparitinase, and the inner surface of the spaces was surrounded by basement membrane components: laminin, fibronectin and type IV collagen. The results of the present study therefore showed that DMBA-induced mammary tumor consists, partly, of a structure resembling human adenoid cystic carcinoma.
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PMID:Immunohistochemical studies of DMBA-induced rat mammary tumors. 245 33

In a randomized trial 2 groups of 28 patients who had undergone transurethral resection of bladder tumors were treated with 20 mg. mitomycin C alone or with 200,000 units hyaluronidase to determine whether adjuvant hyaluronidase would improve tumor recurrence rates. Patient groups were comparable statistically. In the group receiving additive hyaluronidase the percentage of tumor recurrences was decreased significantly (p less than 0.05). Side effects were not increased. Thus, adjuvant hyaluronidase appears to have a role in the metaphylaxis of bladder tumors. The potential reduction of the hyaluronidase dose without loss of protective action and the role of additive hyaluronidase in the systemic treatment of metastatic urothelial tumors remain to be investigated.
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PMID:Metaphylactic effect of mitomycin C with and without hyaluronidase after transurethral resection of bladder cancer: randomized trial. 249 98

In order to analyze the mucoid substance in the epithelial component of synovial sarcoma, electron microscopic and cytochemical studies were made on three of these neoplasms. The mucoid substances in the glandular lumen were intensely stained with ruthenium red (RR), appearing as granular, fibrillar and amorphous structures. RR staining of proteoglycans was diminished after treatment with chondroitinase AC or ABC, and was partially diminished by exposure to streptomyces hyaluronidase. Trypsin treatment did not affect RR staining of proteoglycans in the lumen. On thin sections stained with periodic acid-thiocarbo-hydrazide-silver proteinate (PA-TCH-SP), deposits of reaction product were observed on the mucoid substances within the lumen, and were localized in the Golgi complex, including the rough endoplasmic reticulum, small vesicle and lysosome-like dense body. Trypsin digestion decreased the stain intensity of PA-TCH-SP. These results indicate that the lumen of the gland-like component contains glycoproteins as well as proteoglycans mainly consisting of chondroitin sulfate and hyaluronic acid, and suggest that GERL (Novikoff) is closely related to production, storage and transport of glycoproteins in the cytoplasm of tumor cells.
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PMID:[Ultrastructural cytochemistry of epithelial gland-like component in synovial sarcoma]. 249 43

Seventy five prostatic specimens from cancer, BPH and normal controls were studied by light microscopic histochemical methods for the demonstration of complex carbohydrates and some proteins: 1) alcian blue (AB) (pH 1.0), 2) alcian blue (AB) (pH 2.5), 3) Periodic Acid-Schiff (PAS), 4) peroxidase labelled-Ricinus communis agglutinin-diaminobenzidine (PO-RCA-DAB), 5) Concanavalin A-peroxidase-diaminobenzidine (ConA-PO-DAB), 6) ConA-PO-DAB-periodic acid-m-aminophenol Fast black salt K (ConA-PO-DAB-PA-AP-FBK). For identifying individual acidic and neutral carbohydrates, following procedures of enzyme digestion were performed upon some tissue sections prior to the above histochemical staining: a) sialidase (prior to staining with AB at pH 2.5), b) streptomyces hyaluronidase (prior to staining with AB at pH 2.5), c) testicular hyaluronidase (prior to staining with AB at pH 1.0 or pH 2.5), d) chondroitinase ABC (prior to staining with AB at pH 1.0 or pH 2.5), e) chondroitinase AC (prior to staining with AB at pH 1.0 or pH 2.5), f) alpha-amylase (prior to staining with PAS). In addition, the tissue specimens from prostatic cancer were stained immunohistochemically for demonstration of prostatic acid phosphatase (PAP) and the serum PAP levels were also measured by radioimmunoassay. The histochemical differences in the prostatic tissue among normal control, BPH and cancer as follows. In the tissue of prostatic cancer, chondroitin sulfate A, C and hyaluronic acid were present in the interstitium. Chondroitin sulfate, hyaluronic acid and sialic acid were present in the cytoplasm of cancer cells. In the tissue of BPH chondroitin sulfate B and hyaluronic acid was present in the interstitium and hyaluronic acid was present in the cytoplasm of epitherial cells. In the epithelial basement membrane of the tissue from BPH, chondroitin B and hyaluronic acid were present. 1,2-Glycol groups of neutral complex carbohydrates in the interstitium of prostatic cancer were shown to exist in smaller amounts than in that of BPH. In the cytoplasm of cancer cells the intensity of both PO-RCA-DAB and ConA-PO-DAB staining could be divided into three groups: strong, moderate and weak. In the prostatic cancer there was a good correlation between the intensity of PO-RCA-DAB staining and tumor grade, and intensity of ConA-PO-DAB staining was correlated well with serum PAP level. The cytoplasm of cancer cells showed a positive reaction to PAP immunostaining and no appreciable difference was observed according to tumor grade.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[The histochemistry of complex carbohydrates in the prostatic tumor]. 258 29

We describe a method for establishing the culture of bovine tracheal submucosal gland (BTG) cells, in which we have also examined the influence of a reconstituted basement membrane matrix derived from the Engelbreth-Holm-Swarm tumor (EHS) on the growth and morphological differentiation of these cells. BTG cells have been isolated by tissue enzymatic digestion using trypsin, deoxyribonuclease I, elastase, hyaluronidase and EGTA for 1 hr at 37 degrees C. Afterwards, cells and tissue were collected by centrifugation and were incubated for 15 min with 15% newborn calf serum to inactivate the proteolytic enzymes. Enzymatic digestion using only trypsin, centrifugation and inactivation steps were repeated three times. Using this protocol, we obtained 15 +/- 4 (X 10(6] cells per g of tracheal submucosa with 72 +/- 2% (n = 5) cell viability. On microscopic observation, isolated cells were mainly composed of serous type glandular cells. Cells were cultured in a 1:1 medium of Dulbecco's Modified Eagle's/Ham's F12 supplemented with 10% fetal calf serum and subcultured in either plastic flasks or flasks coated with EHS matrix. On the plastic, the BTG cells exhibited at confluency an epithelioid appearance. They stained positively with the immunofluorescent anticytokeratin antibody and contained PAS-staining granules. By electron microscopy, lactoferrin, a protein marker specific to the serous cells, was demonstrated immunocytochemically in small secretory vesicles. BTG cells cultured on EHS matrix revealed a significantly increased growth in comparison to those cultured on plastic. In post-confluent culture of BTG cells on EHS matrix, we observed numerous dome-like structures formed by differentiated cells which were joined together around luminal spaces.
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PMID:Growth and characterization of isolated bovine tracheal gland cells in culture. Influence of a reconstituted basement membrane matrix. 260 69


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