Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A trypsin-like enzyme has been purified to apparent homogeneity from neuroblastoma cell membranes by a procedure including extraction with Triton X-100, soybean trypsin inhibitor-immobilized Sepharose 4B affinity chromatography, and gel filtration. SDS-polyacrylamide gel electrophoresis under reducing conditions of the purified enzyme gave a single band corresponding to a molecular weight of 28,000. The molecular weight of the enzyme was also estimated to be 32,000 by gel filtration. The pH optimum of the activity was 8.5-9.0. The purified enzyme was inhibited by diisopropylphosphorofluoridate, p-aminobenzamidine, and leupeptin, and moderately by chymostatin, but not, or only scarcely, by bestatin, phosphoramidon, p-chloromercuribenzoate, and N-ethylmaleimide. The substrate subsite specificity of the purified enzyme was broad toward various peptidyl-arginine (or lysine) 4-methylcoumaryl-7-amides, but it cleaved dynorphin(1-17) only at two sites, i.e., between the Arg6-Arg7 and Lys11-Leu12 bonds, both of which correspond to the initial cleavage sites of dynorphin with a membrane preparation of neuroblastoma cells. A trypsin-like enzyme was also purified from a synaptic membrane preparation of rat brain, which shows almost the same properties as those of the enzyme from the neuroblastoma cell membrane. Thus, the trypsin-like enzyme present in the synaptic membrane would participate in the degradation of dynorphin.
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PMID:Membrane-bound trypsin-like enzyme functioning in degradation of dynorphin in neuroblastoma cells. Purification and characterization. 289 72

Human neuroblastoma cells (Platt and La-N1) have previously been shown to adhere and extend neurites on tissue-culture substrata coated with a 120K chymotryptic cell-binding fragment (CBF) of plasma fibronectin (pFN), a fragment which lacks heparan sulfate- and collagen-binding activities, and to adhere to--but not extend neurites on--substrata coated with the heparan sulfate (HS)-binding protein, platelet factor-4 (PF4) (Tobey et al., Exp Cell Res 158 (1985) 395 [3]). The mechanisms of these processes on CBF, on the intact pFN molecule, or on heparin-binding fragments of pFN have been tested using a heptapeptide (peptide A) containing the Arg-Gly-Asp-Ser (RGDS) sequence which recognizes a specific 'receptor' on the surface of a variety of cells or a control peptide with a single amino acid substitution. Adherence and neurite extension were completely inhibited on the 120K CBF by peptide A but not by control peptide; these results indicate that the RGDS-dependent 'receptor' is solely responsible for adhesive responses to the 120K CBF-containing region of the pFN molecule. When peptide A was added to cells on CBF which had already formed neurites to test reversibility, retraction of all neurite processes was induced by 1 h and cells eventually detached. In contrast, on intact pFN, peptide A had very limited effects on either initial adherence or neurite extension, revealing a second 'cell-binding' domain on the fibronectin molecule outside of the 120K region competent for neurite differentiation; addition of peptide A at later times to pFN-adherent, neurite-containing cells could induce only a small subset of neurites to retract, thus supporting evidence for the presence of this second domain. A second 'cell-binding' domain was further confirmed by quantitation of neurite outgrowth on these substrata and by analyses of cells on substrata coated with mixtures of CBF/PF4. When substrata coated with chymotrypsin-liberated HBF were tested in a similar fashion, adherence was rapid but neurite outgrowth required much longer times and was completely sensitive to RGDS peptides; supplementation of cells with the complex ganglioside GT1b could not induce RGDS-resistant neurites on heparin-binding fragments (HBF). These latter results indicate that neurite extension on HBF is a consequence of a low concentration of RGDS-dependent activity in HBF (but not to HS-binding activity as characterized by Tobey et al. [3]) and that the second 'cell-binding' domain is sensitive to chymotrypsin digestion of pFN during the liberation of HBF.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:A second cell-binding domain on fibronectin (RGDS-independent) for neurite extension of human neuroblastoma cells. 295 Dec 67

Human neuroblastoma cells (Platt and La-N1) adhere and extend neurites on a ganglioside GM1-binding substratum provided by cholera toxin B (CTB). These adhesive responses, similar to those on plasma fibronectin (pFN), require the mediation of one or more cell-surface proteins [G. Mugnai and L. A. Culp (1987) Exp. Cell Res. 169, 328]. The involvement of two pFN receptor molecules in ganglioside GM1-mediated responses on CTB have now been tested. In order to test the role of cellular FN binding to its glycoprotein receptor integrin, a soluble peptide containing the Arg-Gly-Asp-Ser (RGDS) sequence was added to the medium. It did not inhibit attachment on CTB but completely inhibited formation of neurites; in contrast, the RGDS peptide minimally inhibited attachment or neurite formation on pFN. Once formed, neurites on CTB became resistant to the peptide. In order to test the role of cell-surface heparan sulfate proteoglycan (HS-PG), two approaches were used. First, the HS-binding protein platelet factor-4 (PF4) was used to dilute CTB or pFN on the substratum or, alternatively, added to the medium. Diluting the substratum ligand with PF4 had no effects on attachment on either CTB or pFN. However, neurite formation on CTB was readily inhibited and on pFN partially inhibited; the effects of PF4 were far greater than a similar dilution with nonbinding albumin. When PF4 was added to the medium of cells, attachment on either substratum was unaffected as was neurite outgrowth on pFN, revealing differences in PF4's inhibition as the substratum-bound or medium-borne component. In contrast, PF4 in the medium at low concentrations (1 microgram/ml) was highly inhibitory for neurite formation on CTB. The second approach utilized the addition of bovine cartilage dermatan sulfate proteoglycan (DS-PG), shown to bind to pFN as well as to substratum-bound CTB by ELISA, or cartilage chondroitin sulfate/keratan sulfate proteoglycan (CS/KS-PG) to the substratum or to the medium. At low concentrations, DS-PG but not CS/KS-PG actually stimulated neurite formation on CTB while at higher concentrations DS-PG completely inhibited attachment and neurite formation. While DS-PG partially inhibited attachment on pFN, it had no effect on neurite formation of the attached cells. Neuroblastoma cells adhered to some extent to substrata coated only with DS-PG, indicating "receptors" for PGs that permit stable interaction.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Ganglioside-dependent adhesion events of human neuroblastoma cells regulated by the RGDS-dependent fibronectin receptor and proteoglycans. 296 69

The amino acid arginine has anabolic and immunostimulatory properties. This study evaluated the potency of arginine in limiting the severe nutritional and immunological insults of protein calorie malnutrition and increasing tumor load. In protein-depleted A/J mice (n = 340) bearing either an immunogenic (C1300) or poorly immunogenic (TBJ) neuroblastoma, arginine supplementation [1%] significantly augmented T lymphocyte responses (mitogenesis, interleukin-2 production) compared with both a glycine-supplemented and nonsupplemented group. Arginine supplementation significantly retarded the growth of C1300 and prolonged median host survival. These results correlated with augmented autologous mixed lymphocyte tumor cell responses and enhanced specific cytotoxicity. This anti-tumor effect was not demonstrated in mice bearing TBJ where both arginine and glycine stimulated tumor growth compared with nonsupplemented mice. There was no significant difference between arginine and glycine in preservation of carcass weight. These studies suggest that the immunostimulatory effects of arginine are not due to supplemental nitrogen and that an associated antitumor effect is dependent on tumor antigenicity.
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PMID:Arginine, protein malnutrition, and cancer. 297 88

Attachment and neurite extension processes have been evaluated for an immortalized derivative cell of a rat dorsal root neuron after fusion with a mouse neuroblastoma cell (the clonal F11 hybrid cell line) and these processes compared with previous studies of neuroblastoma cells, since both cell types may be derived from the neural crest of the developing embryo. Biochemically defined substrata were provided by human plasma fibronectin (pFN), the heparan sulfate-binding protein platelet factor-4 (PF4), and the ganglioside GM1-binding protein cholera toxin B subunit (CTB). While some attachment of unsupplemented cells was noted on CTB substrata, GM1 supplementation permitted F11 cells to attach as well on CTB as on pFN or PF4. On PF4, very few neurite processes were observed while on pFN two morphologically distinct types of neurites could be identified: short, linear processes in a low percentage of cells resembling those of neuroblastoma cells and long, irregular and narrow processes in a higher percentage of cells resembling those of dorsal root neurons. On CTB, neurites of the latter class were even more prominent; however, cell bodies on CTB failed to spread by cytoplasmic extension as commonly observed in F11 cells on pFN and, to some extent, on PF4. The formation of both neurite classes on either pFN or CTB was completely inhibited by low concentrations of an RGDS (Arg-Gly-Asp-Ser) peptide in the medium of cultures, indicating the significance of pFN's binding to cell surface integrin or ganglioside GM1's possible interaction with integrin for mediating the differentiative process. In contrast, neurite formation of neuroblastoma cells is refractile to the soluble peptide as reported previously. Neurite extensions of F11 cells on either pFN or CTB were comparably sensitive to low concentrations of cytochalasin D, revealing the mediation of microfilament reorganization in these processes. Treatment of F11 cells with cycloheximide failed to inhibit neurite extension on pFN but did partially inhibit extension on CTB; this contrasts with the very high sensitivity of neurite formation by neuroblastoma cells on CTB substrata reported previously.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Multiple and alternative adhesive responses on defined substrata of an immortalized dorsal root neuron hybrid cell line. 316 39

A unique tissue kallikrein-binding protein was identified and partially characterized in the brain and serum of Sprague-Dawley rats and in the serum-free conditioned media of mouse anterior pituitary cells (AtT 20) and rodent neuroblastoma x glioma hybrids (NG108-15). Kallikrein and kallikrein-binding protein(s) form SDS- and heat-stable complexes with a molecular weight (Mr) of approximately 92,000. The complex formation of 125I-labelled kallikrein and the binding protein in the serum and brain is inhibited by excess unlabelled rat urinary kallikrein, rat arginine esterase A (a kallikrein-like kininogenase), and human urinary kallikrein. When the active site of kallikrein was blocked by phenylmethylsulfonyl fluoride or D-Phe-D-Phe-L-Arg-CH2Cl, no complex formation was detected. Kallikrein-binding protein only forms complexes with active kallikrein or trypsin-activated prokallikrein but not with prokallikrein. 125I-labelled kallikrein forms a 92-kilodalton protein with binding protein in various brain regions of perfused normotensive rats of the Wistar-Kyoto strain (WKY), including the cerebral cortex, cerebellum and brain stem; but complex formation was not found in corresponding brain regions of the spontaneously hypertensive rat (SHR). Similarly, the kallikrein-binding protein was identified in various tissues including thymus, lung, liver, prostate, Cowper's gland, adrenal gland, kidney, and pancreas of WKY rats but not in tissues of SHR. The results suggest a major difference in the kallikrein-binding protein in hypertensive versus normotensive rats. The role of this specific kallikrein-binding protein in cellular hemodynamic processes and blood pressure regulation remains to be investigated.
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PMID:A major difference of kallikrein-binding protein in spontaneously hypertensive versus normotensive rats. 317 Nov 70

Attachment and neurite extension have been measured when Platt or La-N1 human neuroblastoma cells respond to tissue culture substrata coated with a panel of complementary fragments from the individual chains of human plasma (pFN) or cellular fibronectins (cFN) purified from thermolysin digests. A 110-kD fragment (f110), which contains the Arg-Gly-Asp-Ser sequence (RGDS)-dependent cell-binding domain but no heparin-binding domains and whose sequences are shared in common by both the alpha- and beta-subunits of pFN, facilitated attachment of cells that approached the level observed with either intact pFN or the heparan sulfate-binding platelet factor-4 (PF4). This attachment on f110 was resistant to RGDS-containing peptide in the medium. Neurite outgrowth was also maximal on f110, and half of these neurites were also resistant to soluble RGDS peptide. Treatment of cells with glycosaminoglycan lyases failed to alter these responses on f110. Therefore, there is a second "cell-binding" domain in the sequences represented by f110 that is not RGDS- or heparan sulfate-dependent and that facilitates stable attachment and some neurite outgrowth; this domain appears to be conformation-dependent. Comparisons were also made between two larger fragments generated from the two subunits of pFN-f145 from the alpha-subunit and f155 from the beta-subunit--both of which contain the RGDS-dependent cell-binding domain and the COOH-terminal heparin-binding domain but which differ in the former's containing some IIICS sequence at its COOH terminus and the latter's having an additional type III homology unit. Heparin-binding fragments (with no RGDS activity) of f29 and f38, derived from f145 or f155 of pFN, respectively, and having the same differences in sequence, were also compared with f44 + 47 having the "extra domain" characteristic of cFN. Attachment on f145 was slightly sensitive to soluble RGDS peptide; attachment on f155 was much more sensitive. There were also differences in the percentage of cells with neurites on f145 vs. f155 but neurites on either fragment were completely sensitive to RGDS peptide. Mixing of f29, f38, or PF4 with f110 could not reconstitute the activities demonstrated in f145 or f155, demonstrating that covalently linked sequences are critical in modulating these responses. However, mixing of f44 + 47 from cFN with f110 from pFN increased the sensitivity to RGDS peptide.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Modulation of matrix adhesive responses of human neuroblastoma cells by neighboring sequences in the fibronectins. 334 30

Our studies demonstrate that rat anterior pituitary cells (GH3) are capable of synthesizing and secreting tissue kallikrein together with prolactin and growth hormone. The secretion of prolactin and growth hormone in GH3 cells was measured by two newly developed sensitive radioimmunoassays (RIA), using the polyethylene glycol separation technique. In the direct radioimmunoassay for rat tissue kallikrein, using a polyclonal antiserum which recognizes both active and prokallikrein, the GH3 kallikrein displays parallelism with standard curves of rat urinary kallikrein. The production of immunoreactive kallikrein, prolactin, and growth hormone is time-dependent, and the levels after a 72 h incubation in serum-free media are approximately 12.2 +/- 4.4 ng, 272.2 +/- 33.0 ng, and 475.6 +/- 4.8 ng per 10(6) cells per ml (mean +/- SD, n = 3), respectively. In Western blot analyses, a specific monoclonal antibody to tissue kallikrein (V4D11) identifies GH3-secreted kallikrein as a approximately 39,000 Da protein, slightly larger than approximately 38,000 Da kallikreins of submandibular gland, mouse anterior pituitary cells (AtT 20) or rodent neuroblastoma X glioma hybrid cells (NG108). Kallikrein mRNA in GH3 cells was identified in Northern blot analyses, using a tissue kallikrein cDNA probe. In a RIA using a kallikrein monoclonal antibody (V1C3) recognizing only active kallikrein, kallikrein could not be detected in the media incubated up to 48 h with GH3 cells. However, after trypsin treatment, a time-dependent increase of immunoreactive kallikrein (using monoclonal antibody V1C3), Tos-Arg-OMe esterase, and kinin-releasing activities can be measured in the conditioned media. The activated esterase activity was inhibited by aprotinin and by affinity-purified kallikrein monoclonal antibody (V4D11) in a dose-dependent manner. The data indicated that rat anterior pituitary GH3 cells secrete latent tissue kallikrein, which can be converted to active kallikrein by trypsin. These hormonally responsive cells co-synthesize kallikrein with prolactin and growth hormone and provide a model system for studying the regulation of kallikrein gene expression.
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PMID:Identification of latent tissue kallikrein, prolactin and growth hormone secretion in GH3 pituitary cells using modified radioimmunoassays. 336 Feb 6

Five opioid peptides (immunoreactivity) derived from their respective opioid precursors were measured in neuroblastoma-glioma hybrid cells (NG 108CC15; pmol/g protein): heptapeptide (Tyr-Gly-Gly-Phe-Met-Arg-Phe), 13.0 +/- 2.6; alpha-neoendorphin, 6.6 +/- 0.8; dynorphin A, 4.4 +/- 1.5; dynorphin A 1-8, 1.3 +/- 0.29; beta-endorphin, 0.3 +/- 0.13. These peptides originate from preproenkephalin A (heptapeptide), prodynorphin (alpha-neonedorphin, dynorphin A, dynorphin A 1-8) and proopiomelanocortin (beta-endorphin). The data suggest the expression of all three known opioid precursors in a single hybrid cell line, permitting a simultaneous investigation of the processing of different opioid peptides under identical experimental conditions.
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PMID:Evidence for the expression of peptides derived from three opioid precursors in NG 108CC15 hybrid cells. 356 21

We have identified a tissue-kallikrein-binding protein in human serum and in the serum-free culture media from human lung fibroblasts (WI-38) and rodent neuroblastoma X glioma hybrid cells (NG108-15). Purified and 125I-labelled tissue kallikrein and human serum form an approximately 92,000-Mr SDS-stable complex. The relative quantity of this complex-formation is measured by densitometric scanning of autoradiograms. Complex-formation between tissue kallikrein and the serum binding protein was time-dependent and detectable after 5 min incubation at 37 degrees C, with half-maximal binding at 28 min. Binding of 125I-kallikrein to kallikrein-binding protein is temperature-dependent and can be inhibited by heparin or excess unlabelled tissue kallikrein but not by plasma kallikrein, collagenase, thrombin, urokinase, alpha 1-antitrypsin or kininogens. The kallikrein-binding protein is acid- and heat-labile, as pretreatment of sera at pH 3.0 or at 60 degrees C for 30 min diminishes complex-formation. However, the formed complexes are stable to acid or 1 M-hydroxylamine treatment and can only be partially dissociated with 10 mM-NaOH. When kallikrein was inhibited by the active-site-labelling reagents phenylmethanesulphonyl fluoride or D-Phe-D-Phe-L-Arg-CH2Cl no complex-formation was observed. An endogenous approximately 92,000-Mr kallikrein-kallikrein-binding protein complex was isolated from normal human serum by using a human tissue kallikrein-agarose affinity column. These complexes were recognized by anti-(human tissue kallikrein) antibodies, but not by anti-alpha 1-antitrypsin serum, in Western-blot analyses. The results show that the kallikrein-binding protein is distinct from alpha 1-antitrypsin and is not identifiable with any of the well-characterized plasma proteinase inhibitors such as alpha 2-macroglobulin, inter-alpha-trypsin inhibitor, C1-inactivator or antithrombin III. The functional role of this kallikrein-binding protein and its impact on kallikrein activity or metabolism in vivo remain to be investigated.
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PMID:Identification of a new tissue-kallikrein-binding protein. 364 93


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