title: (-)-Syringaresinol inhibits proliferation of human promyelocytic HL-60 leukemia cells via G1 arrest and apoptosis.
abstract: We examined the effect of (-)-syringaresinol, a furofuran-type lignan isolated from Daphne genkwa, on cell cycle regulation in HL-60 human promyelocytic leukemia cells in vitro. (-)-Syringaresinol decreased the viability of HL-60 cells by inducing G(1) arrest followed by apoptosis in a dose- and time-dependent manner. The G(0)/G(1) phase of the cell cycle is regulated by cyclin-dependent kinases (Cdk), cyclins and cyclin-dependent kinase inhibitors (Cdki). We show by western blot analysis, that the (-)-syringaresinol-induced G(1) arrest was mediated through the increased expression of Cdki proteins (p21(cip1/waf1) and p27(kip1)) with a simultaneous decrease in cdk2, cdk4, cdk6, cyclin D(1), cyclin D(2), and cyclin E expression. The induction of apoptosis after treatment with (-)-syringaresinol for 24 h was demonstrated by morphological changes, DNA fragmentation, altered ratio of Bax/Bcl-2, cleavage of poly(ADP-ribose) polymerase and flow cytometry analysis. (-)-Syringaresinol also induced cytochrome c release and activation of caspase-3 and caspase-9. To our knowledge, this is the first time that (-)-syringaresinol has been reported to potently inhibit the proliferation of human promyelocytic HL-60 cells through G(1) arrest and induction of apoptosis. These findings suggest that (-)-syringaresinol may be a potential chemotherapeutic agent for the treatment of cancer.
authors.affiliation: Natural Medicines Research Center, KRIBB, 111 Gwahangno, Yuseong-gu, Daejeon 305-806, South Korea.
authors.forename: Bo-Young
authors.initials: BY
authors.lastname: Park
authors.forename: Sei-Ryang
authors.initials: SR
authors.lastname: Oh
authors.forename: Kyung-Seop
authors.initials: KS
authors.lastname: Ahn
authors.forename: Ok-Kyong
authors.initials: OK
authors.lastname: Kwon
authors.forename: Hyeong-Kyu
authors.initials: HK
authors.lastname: Lee
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D045304:Cytochromes c / Q000378:metabolism; D005663:Furans / Q000494:pharmacology*; D016193:G1 Phase / Q000187:drug effects*; D018922:HL-60 Cells; D006801:Humans; D017705:Lignans / Q000494:pharmacology*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis
chemical_list: D000970:Antineoplastic Agents; D005663:Furans; D017705:Lignans; D019253:Proto-Oncogene Proteins c-bcl-2; C042192:syringaresinol; D045304:Cytochromes c; D011065:Poly(ADP-ribose) Polymerases