title: Induction of apoptosis in MDA-MB-231 human breast carcinoma cells with an ethanol extract of Cyperus rotundus L. by activating caspases.
abstract: Cyperus rotundus L. belongs to the Cyperaceae family and is a well documented traditional medicinal herb. Its rhizome has been reported to possess wide spectrum pharmacological activities including anti-inflammatory and antioxidant activity. However, the cellular and molecular mechanisms of the anticancer activity have not been elucidated. In the present study, we investigated the pro-apoptotic effects of C. rotundu rhizomes in a human breast carcinoma MDA-MB-231 cell model. Treatment of MDA-MB-231 cells with an ethanol extract of C. rotundu rhizomes (EECR) and a methanol extract of C. rotundu rhizomes (MECR), but not a water extract of C. rotundu rhizomes, resulted in potent antiproliferative activity. The activity of the EECR was higher than that of the MECR and was associated with the induction of apoptosis. The induction of apoptosis by the EECR was associated with upregulation of death receptor 4 (DR4), DR5 and pro-apoptotic Bax, as well as downregulation of anti-apoptotic survivin and Bcl-2. EECR treatment also downregulated Bid expression and activated caspase-8 and -9, the respective initiator caspases of the extrinsic and intrinsic apoptotic pathways. The increase in mitochondrial membrane depolarization was correlated with activation of effector caspase-3 and cleavage of poly(ADP-ribose) polymerase, a vital substrate of activated caspase-3. Blockage of caspase activation by pretreatment with a pan-caspase inhibitor consistently inhibited apoptosis and abrogated growth inhibition in EECR-treated MDA-MB-231 cells. Although reactive oxygen species (ROS) increased following treatment with the EECR, inhibiting ROS with a ROS scavenger did not attenuate EECR-induced apoptosis. Furthermore, inhibitors of phosphatidylinositol 3-kinase (PI3K)/Akt and mitogen-activated protein kinase (MAPK) signaling pathways failed to reverse EECR-induced apoptosis and growth inhibition. These results suggest that the pro-apoptotic activity of the EECR may be regulated by a caspase-dependent cascade through activation of both intrinsic and extrinsic signaling pathways that is not associated with ROS generation or the PI3K/Akt and MAPK pathways.
authors.affiliation: Department of Internal Medicine, Dongeui University College of Korean Medicine, Busan 614-052, Republic of Korea.
authors.forename: Sang Eun
authors.initials: SE
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Dongeui University College of Korean Medicine, Busan 614-052, Republic of Korea.
authors.forename: Won Tak
authors.initials: WT
authors.lastname: Shin
authors.affiliation: Department of Molecular Biology, College of Natural Sciences, Dongeui University, Busan 614-714, Republic of Korea.
authors.forename: Cheol
authors.initials: C
authors.lastname: Park
authors.affiliation: Department of Biochemistry, Dongeui University College of Korean Medicine, Busan 614-052, Republic of Korea.
authors.forename: Su Hyun
authors.initials: SH
authors.lastname: Hong
authors.affiliation: Laboratory of Immunobiology, Department of Marine Life Sciences, Jeju National University, Jeju 690-756, Republic of Korea.
authors.forename: Gi-Young
authors.initials: GY
authors.lastname: Kim
authors.affiliation: Team for Scientification of Korean Medical Intervention (BK21 Plus) and Department of Herbal Pharmacology, Daegu Haany University College of Korean Medicine, Daegu 706-828, Republic of Korea.
authors.forename: Sung Ok
authors.initials: SO
authors.lastname: Kim
authors.affiliation: Division of Applied Life Science (BK 21 Program), Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 660‑701, Republic of Korea.
authors.forename: Chung Ho
authors.initials: CH
authors.lastname: Ryu
authors.affiliation: Department of Internal Medicine, Dongeui University College of Korean Medicine, Busan 614-052, Republic of Korea.
authors.forename: Sang Hoon
authors.initials: SH
authors.lastname: Hong
authors.affiliation: Department of Biochemistry, Dongeui University College of Korean Medicine, Busan 614-052, Republic of Korea.
authors.forename: Yung Hyun
authors.initials: YH
authors.lastname: Choi
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D051017:Apoptosis Regulatory Proteins / Q000235:genetics / Q000378:metabolism; D001943:Breast Neoplasms; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D029786:Cyperus / Q000737:chemistry*; D004354:Drug Screening Assays, Antitumor; D004789:Enzyme Activation; D000431:Ethanol / Q000737:chemistry; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology*; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D059748:Proteolysis; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D027343:Rhizome / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D051017:Apoptosis Regulatory Proteins; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D012997:Solvents; D000431:Ethanol; C499320:PARP1 protein, human; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases; D051057:Proto-Oncogene Proteins c-akt; D020169:Caspases