title: Cytotoxicity of Vitex agnus-castus fruit extract and its major component, casticin, correlates with differentiation status in leukemia cell lines.
abstract: We have demonstrated that an extract from the ripe fruit of Vitex agnus-castus (Vitex) exhibits cytotoxic activities against various types of solid tumor cells, whereas its effects on leukemia cells has not been evaluated to date. In this study, the effects of Vitex and its major component, casticin, on leukemia cell lines, HL-60 and U-937, were investigated by focusing on proliferation, induction of apoptosis and differentiation. Identification and quantitation by NMR spectroscopy showed that casticin accounted for approximate 1% weight of Vitex. Dose-dependent cytotoxicity of Vitex and casticin was observed in both cell lines, and HL-60 cells were more sensitive to the cytotoxicity of Vitex/casticin compared to U-937 cells. Furthermore, compared to unstimulated HL-60 cells, phorbol 12-myristate 13-acetate (PMA)- and 1,25-dihydroxyvitamin D₃ (VD₃)-differentiated HL-60 cells acquired resistance to Vitex/casticin based on the results from cell viability and apoptosis induction analysis. Since the HL-60 cell line is more immature than the U-937 cell line, these results suggested that the levels of cytotoxicity of Vitex/casticin were largely attributed to the degree of differentiation of leukemia cells; that is, cell lines with less differentiated phenotype were more susceptible than the differentiated ones. RT-PCR analysis demonstrated that PMA upregulated the expression of intercellular adhesion molecule-1 (ICAM-1) in HL-60 cells, and that anti-ICAM-1 monoclonal antibody not only abrogated PMA-induced aggregation and adhesion of the cells but also restored its sensitivity to Vitex. These results suggested that ICAM-1 plays a crucial role in the acquired resistance in PMA-differentiated HL-60 cells by contributing to cell adhesion. These findings provide fundamental insights into the clinical application of Vitex/casticin for hematopoietic malignancy.
authors.affiliation: Department of Clinical Molecular Genetics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192-0392, Japan.
authors.forename: Hidetomo
authors.initials: H
authors.lastname: Kikuchi
authors.forename: Bo
authors.initials: B
authors.lastname: Yuan
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Nishimura
authors.forename: Masahiko
authors.initials: M
authors.lastname: Imai
authors.forename: Ryota
authors.initials: R
authors.lastname: Furutani
authors.forename: Saki
authors.initials: S
authors.lastname: Kamoi
authors.forename: Misako
authors.initials: M
authors.lastname: Seno
authors.forename: Shin
authors.initials: S
authors.lastname: Fukushima
authors.forename: Shingo
authors.initials: S
authors.lastname: Hazama
authors.forename: Chieko
authors.initials: C
authors.lastname: Hirobe
authors.forename: Kunio
authors.initials: K
authors.lastname: Ohyama
authors.forename: Xiao-Mei
authors.initials: XM
authors.lastname: Hu
authors.forename: Norio
authors.initials: N
authors.lastname: Takagi
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Hirano
authors.forename: Hiroo
authors.initials: H
authors.lastname: Toyoda
mesh_terms: D000328:Adult; D017209:Apoptosis / Q000187:drug effects; D002117:Calcitriol / Q000494:pharmacology; D002120:Calcium Channel Agonists / Q000494:pharmacology; D002273:Carcinogens / Q000494:pharmacology; D002448:Cell Adhesion / Q000502:physiology; D002454:Cell Differentiation / Q000187:drug effects* / Q000502:physiology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D019008:Drug Resistance, Neoplasm; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D005419:Flavonoids / Q000494:pharmacology*; D018922:HL-60 Cells; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis; D007938:Leukemia / Q000188:drug therapy*; D010936:Plant Extracts / Q000494:pharmacology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D020950:Vitex
chemical_list: D002120:Calcium Channel Agonists; D002273:Carcinogens; D004365:Drugs, Chinese Herbal; D005419:Flavonoids; D010936:Plant Extracts; C553090:Vitex agnus castus extract; D018799:Intercellular Adhesion Molecule-1; C054133:casticin; D002117:Calcitriol; D013755:Tetradecanoylphorbol Acetate