title: Chromene induces apoptosis via caspase-3 activation in human leukemia HL-60 cells.
abstract: In this study, the potent anti-tumor effects of brown algae on human leukemia HL-60 cells were investigated. The Sargassum siliquastrum extract among the 14 species of brown algae exhibited profound growth inhibitory effect on HL-60 cells in the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, therefore, S. siliquastrum was selected for use in further experiments. The highest inhibitory activity of S. siliquastrum on HL-60 cells was detected in the chloroform fraction, and the active compound was identified as a kind of chromene, sargachromanol E (SE). SE treatment showed significant growth inhibitory effects on HL-60 cells in a dose-dependent manner by inducing apoptosis, as evidenced by the formation of apoptotic bodies, fragmented DNA ladder, and the accumulation of DNA in the sub-G(1) phase of cell cycle. SE induced apoptosis was accompanied by downregulation of Bcl-xL, upregulation of Bax, activation of caspase-3, and cleavage of poly (ADP-ribose) polymerase (PARP). Moreover, z-DEVD-fmk, a caspase-3 inhibitor, significantly inhibited cell cytotoxicity, apoptotic characteristics such as apoptotic bodies, sub-G(1) DNA content, and cleavage of PARP induced by SE. These results suggest that SE exerts its growth inhibitory effects on HL-60 cells through caspase-3-mediated induction of apoptosis. Therefore, SE offers promising chemotherapeuric potential to prevent cancers such as human leukemia.
authors: Marine Living Resources Research Department, Korea Ocean Research and Development Institute, Ansan 426-744, Republic of Korea.
authors: Soo-Jin
authors: SJ
authors: Heo
authors: Kil-Nam
authors: KN
authors: Kim
authors: Weon-Jong
authors: WJ
authors: Yoon
authors: Chulhong
authors: C
authors: Oh
authors: Young-Ung
authors: YU
authors: Choi
authors: Abu
authors: A
authors: Affan
authors: Yeon-Ju
authors: YJ
authors: Lee
authors: Hyi-Seung
authors: HS
authors: Lee
authors: Do-Hyung
authors: DH
authors: Kang