title: Significance of mitochondrial calcium and nitric oxide for apoptosis of human breast cancer cells induced by tamoxifen and etoposide.
abstract: In the present study, we tested the significance of mitochondria for apoptosis upon exposure to tamoxifen and etoposide using two human breast cancer cell lines, MCF-7 and MDA-MB-231. We showed that both tamoxifen and etoposide induced apoptosis, increased intramitochondrial calcium and nitric oxide, and decreased mitochondrial transmembrane potential in both cell lines. Both drugs increased mitochondrial protein tyrosine nitration and caused release of cytochrome c from the mitochondria of both cell lines. This study suggests that tamoxifen and etoposide utilize a common mechanism to induce apoptosis in MCF-7 and MDA-MB-231 cells.
authors.affiliation: Department of Surgery, Davis Heart and Lung Research Institute, and Institute of Mitochondrial Biology, The Ohio State University, Columbus, OH 43210, USA.
authors.forename: Arti
authors.initials: A
authors.lastname: Parihar
authors.forename: Mordhwaj S
authors.initials: MS
authors.lastname: Parihar
authors.forename: Pedram
authors.initials: P
authors.lastname: Ghafourifar
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D001943:Breast Neoplasms / Q000473:pathology*; D002118:Calcium / Q000378:metabolism*; D045744:Cell Line, Tumor; D045304:Cytochromes c / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005047:Etoposide / Q000494:pharmacology*; D005260:Female; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D009569:Nitric Oxide / Q000378:metabolism*; D013629:Tamoxifen / Q000494:pharmacology*; D013997:Time Factors; D014443:Tyrosine / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D013629:Tamoxifen; D009569:Nitric Oxide; D014443:Tyrosine; D005047:Etoposide; D045304:Cytochromes c; D002118:Calcium