title: Green tea polyphenols induce cell death in breast cancer MCF-7 cells through induction of cell cycle arrest and mitochondrial-mediated apoptosis.
abstract: In order to study the molecular mechanisms of green tea polyphenols (GTPs) in treatment or prevention of breast cancer, the cytotoxic effects of GTPs on five human cell lines (MCF-7, A549, Hela, PC3, and HepG2 cells) were determined and the antitumor mechanisms of GTPs in MCF-7 cells were analyzed. The results showed that GTPs exhibited a broad spectrum of inhibition against the detected cancer cell lines, particularly the MCF-7 cells. Studies on the mechanisms revealed that the main modes of cell death induced by GTPs were cell cycle arrest and mitochondrial-mediated apoptosis. Flow cytometric analysis showed that GTPs mediated cell cycle arrest at both G1/M and G2/M transitions. GTP dose dependently led to apoptosis of MCF-7 cells via the mitochondrial pathways, as evidenced by induction of chromatin condensation, reduction of mitochondrial membrane potential (ΔΨm), improvement in the generation of reactive oxygen species (ROS), induction of DNA fragmentation, and activations of caspase-3 and caspase-9 in the present paper.
authors.affiliation: Department of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China.
authors.forename: Shu-Min
authors.initials: SM
authors.lastname: Liu
authors.affiliation: Department of Food Science and Engineering, Jinan University, Guangzhou 510632, China.
authors.forename: Shi-Yi
authors.initials: SY
authors.lastname: Ou
authors.affiliation: Department of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China.
authors.forename: Hui-Hua
authors.initials: HH
authors.lastname: Huang
mesh_terms: D000072283:A549 Cells; D017209:Apoptosis; D053148:Caspase 3 / Q000378:metabolism; D053453:Caspase 9 / Q000378:metabolism; D059447:Cell Cycle Checkpoints / Q000187:drug effects*; D045744:Cell Line, Tumor; D002470:Cell Survival; D002843:Chromatin / Q000737:chemistry; D053938:DNA Fragmentation; D005434:Flow Cytometry; D006160:Guanosine Triphosphate / Q000378:metabolism; D006367:HeLa Cells; D056945:Hep G2 Cells; D006801:Humans; D061986:MCF-7 Cells; D053078:Membrane Potential, Mitochondrial; D008928:Mitochondria / Q000378:metabolism*; D059808:Polyphenols / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013662:Tea
chemical_list: D002843:Chromatin; D059808:Polyphenols; D017382:Reactive Oxygen Species; D013662:Tea; D006160:Guanosine Triphosphate; C505407:CASP3 protein, human; C506433:CASP9 protein, human; D053148:Caspase 3; D053453:Caspase 9
keywords: Green tea polyphenol (GTP); Breast cancer; MCF-7 cells; Mitochondrial-mediated apoptosis; Cell death; Cell cycle arrest