Chinese medicinal herb, Acanthopanax gracilistylus, extract induces cell cycle arrest of human tumor cells in vitro.
We investigated the effect of a Chinese medicinal herb, Acanthopanax gracilistylus (AG), extract (E) on the growth of human tumor cell lines in vitro. AGE markedly inhibited the proliferation of several tumor cell lines such as MT-2, Raji, HL-60, TMK-1 and HSC-2. The activity was associated with a protein of 60 kDa, which was purified by gel-filtration chromatography. Cell viability analyses indicated that the treatment with AGE inhibits cell proliferation, but does not induce cell death. The mechanism of AGE-induced inhibition of tumor cell growth involves arrest of the cell cycle at the G(0) / G(1) stage without a direct cytotoxic effect. The cell cycle arrest induced by AGE was accompanied by a decrease of phosphorylated retinoblastoma (Rb) protein. Furthermore, cyclin-dependent kinases 2 and 4 (Cdk2 and Cdk4), which are involved in the phosphorylation of Rb, were also decreased. These results suggest that AGE inhibits tumor cell growth by affecting phosphorylated Rb proteins and Cdks.
Shan
B E
BE
Department of Immunology, University of Occupational and Environmental Health, School of Medicine, Yahatanishi-ku, Kitakyushu 807-8555, Japan.
Zeki
K
K
Sugiura
T
T
Yoshida
Y
Y
Yamashita
U
U
D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D042846:CDC2-CDC28 Kinases; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D051357:Cyclin-Dependent Kinase 2; D051358:Cyclin-Dependent Kinase 4; D018844:Cyclin-Dependent Kinases / Q000378:metabolism; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D006801:Humans; D010766:Phosphorylation; D010936:Plant Extracts / Q000494:pharmacology; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011518:Proto-Oncogene Proteins; D016160:Retinoblastoma Protein / Q000378:metabolism; D014407:Tumor Cells, Cultured
D000972:Antineoplastic Agents, Phytogenic; D004365:Drugs, Chinese Herbal; D010936:Plant Extracts; D011518:Proto-Oncogene Proteins; D016160:Retinoblastoma Protein; D017346:Protein Serine-Threonine Kinases; D042846:CDC2-CDC28 Kinases; C495894:CDK2 protein, human; C495900:CDK4 protein, human; D051357:Cyclin-Dependent Kinase 2; D051358:Cyclin-Dependent Kinase 4; D018844:Cyclin-Dependent Kinases