title: Delayed Cell Cycle Progression and Apoptosis Induced by Hemicellulase-Treated Agaricus blazei.
abstract: We examined the effects of hemicellulase-treated Agaricus blazei (AB fraction H, ABH) on growth of several tumor cell lines. ABH inhibited the proliferation of some cell lines without cytotoxic effects. It markedly prolonged the S phase of the cell cycle. ABH also induced mitochondria-mediated apoptosis in different cell lines. However, it had no impact on the growth of other cell lines. ABH induced strong activation of p38 mitogen-activated protein kinase (MAPK) in the cells in which it evoked apoptosis. On the other hand, ABH showed only a weak p38 activation effect in those cell lines in which it delayed cell cycle progression with little induction of apoptosis. However, p38 MAPK-specific inhibitor inhibited both ABH-induced effects, and ABH also caused apoptosis in the latter cells under conditions of high p38 MAPK activity induced by combined treatment with TNF-alpha. These results indicate that the responsiveness of p38 MAPK to ABH, which differs between cell lines, determines subsequent cellular responses on cell growth.
authors.affiliation: Department of Alternative Medicine and Bioregulation, Faculty of Medicine and Department of Microbiology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi Yamanashi, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Kawamura
authors.forename: Hirotake
authors.initials: H
authors.lastname: Kasai