Lectins isolated from Korean mistletoe ( Viscum album coloratum) induce apoptosis in tumor cells

• Published in: Cancer letters 1999-02, Vol.136 (1), p.33-40
• Main Authors: Yoon, Taek Joon, Yoo, Yung Choon, Kang, Tae Bong, Shimazaki, Kei-ichi, Song, Seong Kyu, Lee, Kwan Hee, Kim, Seon Ho, Park, Choon Ho, Azuma, Ichiro, Kim, Jong Bae
• Format: Article
• Language: English
• Subjects: Animals; Antineoplastic agents; Antineoplastic Agents - chemistry; Antineoplastic Agents - isolation & purification; Antineoplastic Agents - pharmacology; Antitumor activity; Apoptosis; Apoptosis - drug effects; Biological and medical sciences; Chemotherapy; Cytotoxicity; Dose-Response Relationship, Drug; Europe; Humans; Korea; Korean mistletoe; Lectin; Lectins - chemistry; Lectins - isolation & purification; Lectins - pharmacology; Medical sciences; Mice; Mistletoe; Neoplasms - drug therapy; Neoplasms - physiopathology; Pharmacology. Drug treatments; Plant Extracts - chemistry; Plant Extracts - isolation & purification; Plant Extracts - pharmacology; Plant Lectins; Plants, Medicinal; Tumor Cells, Cultured
• ISSN: 0304-3835; 1872-7980
• DOI: 10.1016/S0304-3835(98)00300-0

Cytotoxic lectins (KML-C) were isolated from an extract of Korean mistletoe [ Viscum album C. ( coloratum)] by affinity chromatography on a hydrolysed Sepharose 4B column, and the chemical and biological properties of KML-C were examined, partly by comparing them with a lectin (EML-1) from European mistletoe[ Viscum album L. (loranthaceae)]. The hemagglutinating activity of KML-C was inhibited by N-acetyl- d-galactosamine and d-galactose at the minimum concentrations of 6.3 and 12.5 μM/ml, respectively. Further biochemical analyses indicated that KML-C consists of four chains ( M r = 27.5, 30, 31 and 32.5 kDa) which, in some of the molecules, are disulfide-linked, and that the chains of KML-C are distributed over a broad range of isoelectric points (p I), 8.0 to 9.0, whereas the range for EML-1 is 6.6–7.0. A difference was also observed between the N-terminal sequences of KML-C and EML-1. The isolated lectins showed strong cytotoxicity against various human and murine tumor cells, and the cytotoxic activity of KML-C was higher than that of EML-1. Tumor cells treated with KML-C exhibited typical patterns of apoptotic cell death, such as apparent morphological changes and DNA fragmentation, and its apoptosis-inducing activity was blocked by addition of Zn 2+, an inhibitor of Ca 2+/Mg 2+-dependent endonucleases, in a dose-dependent manner. These results suggest that KML-C is a novel lectin related to the cytotoxicity of Korean mistletoe, and that its cytotoxic activity against tumor cells is due to apoptosis mediated by Ca 2+/Mg 2+-dependent endonucleases.