• YAKHAK HOEJI
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• v.46 no.1
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• pp.11-17
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• 2002

$\beta$-Immunan, a proteoglycan, was isolated from the mycelium of Canoderma lucidum which belongs to a medicinal mushroom. The effects of $\beta$-Immunan on cell-cell and cell-matrix interactions mediated by carbohydrate-recognition and the mechanism responsible for the inhibition of experimental metastasis of Bl6-F10 and B16/BL6 murine melanoma were studied. The results showed that $\beta$-Immunan inhibited Bl6-Fl melanoma cell's adhesion to laminin and asialofetuin-induced homotypic aggregation and reduced invasion against Bl6-F10 murine melanoma cells through matrigel in vivo assay. When $\beta$-Immunan was intraperitoneally administrated to C57B/6 mice bearing B16/BL6 murine melanoma cells, it was decreased the number of pulmonary metastatic colony by the dose dependent manner ranging from 20 to 100 mg/kg/day. The results indirectly indicate that clinical treatment with $\beta$-Immunan might be expected to exhibit anti-metastatic effect. In the pulmonary metastasis, the number of pulmonary metastatic colony of melanoma when $\beta$-Immunan was intraperitoneally administrated to C57BL/6 mice bearing B16/BL6 murine melanoma cells by intravenous injection were decreased by the dose dependent manner ranging from 20 to 100 mg/kg/day.

• Korean Journal of Veterinary Research
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• v.37 no.3
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• pp.547-554
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• 1997

Galectin-3 is known as an animal ${\beta}$-galactoside-binding lectin charicterized with S-type carbohydrate recognition domain. It plays a role in growth, adherence and movement of cells. It is, also, related to the cell transformation and metastasis of tumor cells. In this study, we have expressed and purified recombinant human galectin-3 (rHgalectin-3) using E coli system and asialofetuin affinity chromatography for the future development of monoclonal antibody to Hgalectin-3, which is suggested as the tumor marker for the gastric and thyroid gland cancers. Expressed protein was confirmed as the Hgalectin-3 by immunoblot with cross-reactive murine monoclonal antibody. Lectin activity and specificity of purified protein were, also, confirmed by the competitive inhibition with galectin-3 specific carbohydrate, lactose. Like physiological galectin-3, lectin activity of the molecule was not changed in nonreduced condition. Dimer formation, furthermore, was observed at high concentration of the protein even in the reduced condition, which is well known in physiological galectin-3. These results showed purified rHgalectin-3 has the same activity and molecular nature compared to the physiological galectin-3.

• BMB Reports
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• v.40 no.3
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• pp.358-367
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• 2007

A novel mannose-binding tuber lectin with in vitro antiproliferative activity towards human cancer cell lines and antiviral activity against HSV-II was isolated from fresh tubers of a traditional Chinese medicinal herb, Typhonium divaricatum (L.) Decne by a combined procedure involving extraction, ammonium sulfate precipitation, ion exchange chromatography on DEAE-SEPHAROSE, CM-SEPHAROSE and gel-filtration on sephacryl S-200. The apparent molecular mass of the purified Typhonium divaricatum lectin (TDL) was 48 kDa. TDL exhibits hemagglutinating activity toward rabbit erythrocytes at 0.95 $\mu$g/ml, and its activity could be strongly inhibited by mannan, ovomucoid, asialofetuin and thyroglobulin. TDL showed antiproliferative activity towards some well established human cancer cell lines, e.g. Pro-01 (56.7 $\pm$ 6.8), Bre-04 (41.5 $\pm$ 4.8), and Lu-04 (11.4 $\pm$ 0.3). The anti-HSV-II activity of TDL was elucidated by testing its HSV-II infection inhibitory activity in Vero cells with $TC_50$ and $EC_50$ of 5.176 mg/ml and 3.054 $\mu$g/ml respectively. The full-length cDNA sequence of TDL was 1145 bp and contained an 813-bp open reading frame (ORF) encoding a 271 amino acid precursor of 29-kDa. Homology analysis showed that TDL had high homology with many other mannose-binding lectins. Secondary and three-dimensional structures analyses showed that TDL is heterotetramer and similar with lectins from mannose-binding lectin superfamily, especially those from family Araceae.

• Journal of Life Science
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• v.11 no.1
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• pp.57-64
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• 2001

The cDNA encoding human NeuAc ${\alpha}$2,3Gal$\beta$ 1,3GalNAc GalNac ${\alpha}$2,6-Sialyltransferase (hST6GalNac IV) was isolated by screening of human fetal liver cDNA library with a DNA probe generated from the cDNA sequence of mouse ST6Gal NAc IV (mkST6GalNAc IV). The cDNA sequence included an open reading frame coding for 302 amino acids, and comparative analysis of this cDNA with mST6GalNAc IV showed that each sequence of the predicted coding region contains 88% and 85% identifies in nucleotide and amino acid levels, respecively. The primary structure of this enzyme suggested a putative domain structure, like that in other glycosyltransferases, consisting of a short N-terminal cytoplamic domain, a transmembrane domain and a large C-terminal active domain. This enzyme expressed in COS-7 cells echibited transferase activity toward NeuAc ${\alpha}$2,3Gal$\beta$ 1,3GalNAc, fetuin and GM1b, although the activity toward the later is very low, no significant activity being detected toward Gal${\beta}$ 1,3Gal NAc or asialofetuin, the other glycoprotein substrates tested. The $^{14}$ C-sialylated residue of fetuin sialylated by this enzyem with CMP-[$^{14}$C]NeuAc was sensitive to treatment with ${\alpha}$2,8-specific sialidase of Vibrio cholerae but resistant to treatment with ${\alpha}$2,3-specific sialidase (NaNase I), and ${\alpha}$2,3- and ${\alpha}$2,8-specific sialidase of Newcastle disease virus. These results clearly indicated that the expressed enzyme is a type of GalNAc ${\alpha}$2,6-sialyltransferase like mST6GalNAc IV, which requires sialic acid residues linked to Gal${\beta}$1,3GalNAc-residues for its activity.