title: Genistein-induced apoptosis of human breast cancer MCF-7 cells involves calpain-caspase and apoptosis signaling kinase 1-p38 mitogen-activated protein kinase activation cascades.
abstract: The molecular mechanisms of genistein-induced apoptosis of human breast cancer MCF-7 cells were investigated. Genistein showed 50% cell growth inhibition at IC50=27.5+/-0.8 micromol/l in 24 h incubation under 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay conditions. Genistein is known to express both cell growth activity at nanomolar concentrations and anti-cell growth activity at micromolar concentrations. It was found that genistein at 100 micromol/l concentration effectively induced apoptosis of MCF-7 cells in 24 h. Genistein-induced apoptosis involved activation of calpain, caspase 7 and poly(ADP ribose) polymerase. Dantrolene, an inhibitor of Ca release from the endoplasmic reticulum, inhibited genistein-induced activation of calpain and caspase 7, in addition to effectively negating genistein-induced apoptosis. MCF-7 cells treated with genistein also showed increased phosphorylation of p38 mitogen-activated protein kinase, whereas no effect was observed for extracellular signal-regulating kinase 1/2. Phosphorylation of apoptosis signaling kinase 1, an upstream regulator of p38 mitogen-activated protein kinase, was also increased by genistein treatment. Genistein-induced phosphorylation of apoptosis signaling kinase 1 and p38 mitogen-activated protein kinase was diminished by the presence of dantrolene. These results suggest that genistein-induced apoptosis in MCF-7 cells is mediated through calpain-caspase 7 and apoptosis signaling kinase 1-p38 mitogen-activated protein kinase activation cascades that involve Ca release from the endoplasmic reticulum.
authors.affiliation: Department of Advanced Technology Fusion, Konkuk University, Seoul, South Korea.
authors.forename: Hye-Young
authors.initials: HY
authors.lastname: Shim
authors.forename: Jong-Hwa
authors.initials: JH
authors.lastname: Park
authors.forename: Hyun-Dong
authors.initials: HD
authors.lastname: Paik
authors.forename: Seung-Yeol
authors.initials: SY
authors.lastname: Nah
authors.forename: Darrick S H L
authors.initials: DS
authors.lastname: Kim
authors.forename: Ye Sun
authors.initials: YS
authors.lastname: Han
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D001943:Breast Neoplasms / Q000473:pathology; D002118:Calcium / Q000378:metabolism; D002154:Calpain / Q000378:metabolism*; D053179:Caspase 7 / Q000378:metabolism*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004721:Endoplasmic Reticulum / Q000187:drug effects / Q000201:enzymology; D005260:Female; D019833:Genistein / Q000494:pharmacology*; D006801:Humans; D048848:MAP Kinase Kinase Kinase 5 / Q000378:metabolism*; D010766:Phosphorylation; D015398:Signal Transduction; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D019833:Genistein; D048051:p38 Mitogen-Activated Protein Kinases; D048848:MAP Kinase Kinase Kinase 5; D002154:Calpain; D053179:Caspase 7; D002118:Calcium