title: Genistein enhances the cisplatin-induced inhibition of cell growth and apoptosis in human malignant melanoma cells.
abstract: Genistein, a naturally occurring isoflavone found chiefly in soybeans, has been reported to be a potent antitumor agent. Genistein is presumed to exert multiple effects related to the inhibition of cancer growth. Metastatic melanoma is a chemotherapy-refractory neoplasm. The present study was designed to explore the possible activity of genistein to inhibit the aberrant proliferation and to induce apoptosis of human malignant melanoma cells in cooperation with cisplatin treatment. Five human melanoma cell lines were utilized for these experiments. Genistein at physiologic concentrations (20 microM) did not induce apoptosis by itself but did enhance cisplatin-induced apoptosis in all five human melanoma cell lines tested. The enhanced susceptibility among the cell lines was diverse. Changes in the expression of two anti-apoptotic proteins, bcl-2 and bcl-xL, and one pro-apoptotic protein, apoptotic protease activating factor-1 (Apaf-1), were examined. Genistein alone or cisplatin alone generally did not alter bcl-2 expression or bcl-xL expression, but slightly increased Apaf-1 in some cell lines. The combined treatment with genistein and cisplatin significantly reduced bcl-2 and bcl-xL protein and increased Apaf-1 protein expression. These data suggest that genistein therapy may enhance the chemosensitivity of melanoma patients.
authors.affiliation: Division of Dermatology, Department of Clinical Molecular Medicine, Translational Medical Faculty of Medicine, Kobe University Graduate School of Medicine, Kobe, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Tamura
authors.forename: Toshinori
authors.initials: T
authors.lastname: Bito
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Ichihashi
authors.forename: Masato
authors.initials: M
authors.lastname: Ueda
mesh_terms: D000328:Adult; D000972:Antineoplastic Agents, Phytogenic / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects; D018797:Cell Cycle Proteins / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D045744:Cell Line, Tumor; D002945:Cisplatin / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D005260:Female; D019833:Genistein / Q000627:therapeutic use*; D006801:Humans; D008546:Melanoma, Experimental / Q000188:drug therapy*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D018797:Cell Cycle Proteins; D019833:Genistein; D002945:Cisplatin