title: Lignans extracted from Vitex negundo possess cytotoxic activity by G2/M phase cell cycle arrest and apoptosis induction.
abstract: Evn-50 is a lignan compounds mixture extracted from Vitex negundo, a widely used herb in traditional Chinese medicine. This study is aimed to define the spectrum of cytotoxic activity of EVn-50, and also to investigate mechanisms underlying the anticancer actions via assessing the influence on cell cycle using EVn-50, and the lignan compound VB1 purified from EVn-50. The cytotoxic effect of EVn-50 and VB1 was determined with SRB assay using a panel of cancer cell lines. Breast cancer cell line MDA-MB-435 and liver cancer cell line SMMC-7721 were selected for further evaluating the effect of EVn-50 or VB1 on cell cycle by flow cytometric analysis. Apoptosis exerted by EVn-50 or VB1 was measured by TUNEL assay and DAPI staining, and Western blot analysis was utilized to assess the influence on expression and phosphorylation of proteins which are closely related to cell cycle and apoptosis. EVn-50 possessed a broad spectrum of in vitro anticancer activity for those tested cancer cells, especially sensitive to MDA-MB-435, SKOV-3, BXPC-3, SMMC-7721, MCF-7, HO-8910, SGC-7901, BEL-7402, HCT-116, and 786-O, with the respective IC50 below 10 μg/ml. Treatment with EVn-50 or VB1 resulted in arresting the MDA-MB-435 and SMMC-7721 cells at G2/M phase, which was further supported by observations of increased phosphorylation of Histone 3 at Ser10, phosphorylation of Cdk1 at Tyr15, expression of cyclin B1, and decreased expression of Cdc25c. Moreover, we found that exposure of MDA-MB-435 cells to EVn-50 or VB1 caused obvious apoptosis of MDA-MB-435 cells. Our data show that EVn-50, lignan compounds extracted from Vitex negundo, possesses a broad spectrum cytotoxic effect via arresting cancer cells at G2/M phase cell cycle and subsequently inducing apoptosis.
authors.affiliation: Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai 201203, PR China.
authors.forename: Hong
authors.initials: H
authors.lastname: Xin
authors.forename: Ying
authors.initials: Y
authors.lastname: Kong
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.forename: Yingjun
authors.initials: Y
authors.lastname: Zhou
authors.forename: Yizhun
authors.initials: Y
authors.lastname: Zhu
authors.forename: Dapeng
authors.initials: D
authors.lastname: Li
authors.forename: Wenfu
authors.initials: W
authors.lastname: Tan
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D016203:CDC2 Protein Kinase / Q000378:metabolism; D045744:Cell Line, Tumor / Q000187:drug effects; D056744:Cyclin B1 / Q000378:metabolism; D004354:Drug Screening Assays, Antitumor; D005260:Female; D059565:G2 Phase Cell Cycle Checkpoints / Q000187:drug effects*; D006801:Humans; D020128:Inhibitory Concentration 50; D017705:Lignans / Q000494:pharmacology*; D059566:M Phase Cell Cycle Checkpoints / Q000187:drug effects*; D010766:Phosphorylation / Q000187:drug effects; D010946:Plants, Medicinal / Q000737:chemistry; D014443:Tyrosine / Q000378:metabolism; D020950:Vitex / Q000737:chemistry*; D020687:cdc25 Phosphatases / Q000378:metabolism
chemical_list: D000972:Antineoplastic Agents, Phytogenic; C534699:CCNB1 protein, human; D056744:Cyclin B1; D017705:Lignans; D014443:Tyrosine; D016203:CDC2 Protein Kinase; C517009:CDC25C protein, human; D020687:cdc25 Phosphatases