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...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 mitochondrialmediated 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（ΔΨ_m）, 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.展开更多
OBJECTIVE： To investigate the anti-breast cancer （BC） effects and mechanisms of action of Xihuang pill （XHP） by conducting in vitro experiments on hu- man BC cell lines. METHODS： Two human BC cell lines （MCF-7 ...OBJECTIVE： To investigate the anti-breast cancer （BC） effects and mechanisms of action of Xihuang pill （XHP） by conducting in vitro experiments on hu- man BC cell lines. METHODS： Two human BC cell lines （MCF-7 and MDA- MB231） were cultured and treated with XHP. Cell viability was detected using the 3-（4, 5-Dimeth- ylthiazol-2-yl）-2, 5-diphenyltetrazolium bromide （MTT） assay. Flow cytometry was used to measure the cell cycle and apoptosis. The cell cycle was ana- lyzed with propidium iodide staining. Apoptosis was evaluated using the Annexin V-fluorescein iso- thiocyanate/propidium iodide method. Western blotting was used to analyze the expression of es- trogen receptor （ER）-α and ER-13.RESULTS： XHP had growth-inhibitory effects on MCF-7 and MDA-MB231 cells with a half-maximal inhibitory concentration （IC50） of 10.14 mg/mL （MCF-7） and 8.98 mg/mL （MDA-MB231）. Apoptosis was induced to some extent. Certain changes in the ER were caused. Upregulation of ER-a protein was found in MCF-7 cells. ER-β expression in MDA-MB231 cells was increased. Cell-cycle arrest was not observed in the two BC cell lines. ER-β ex- pression in MCF-7 cells was unchanged. No ER-a ex- pression was shown in MDA-MB231 cells. CONCLUSION： These data suggest that XHP can af- fect cell viability and cause apoptosis, but that the cell cycle is not blocked. XHP has a certain impact on ER expression, but its mechanisms of action of anti-13C effects may not be due to regulation of ER expression.展开更多
基金Project supported by the Research Fund for the Doctoral Program of Higher Education of China(No.20120172110017)the National Natural Science Foundation of China(Nos.31471673 and 31271978)
文摘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 mitochondrialmediated 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（ΔΨ_m）, 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.
基金Supported by the Beijing Traditional Chinese Medicine Science and Technology Project(QN2010-3)National Natural Science Foundation of China(No.81001564)
文摘OBJECTIVE： To investigate the anti-breast cancer （BC） effects and mechanisms of action of Xihuang pill （XHP） by conducting in vitro experiments on hu- man BC cell lines. METHODS： Two human BC cell lines （MCF-7 and MDA- MB231） were cultured and treated with XHP. Cell viability was detected using the 3-（4, 5-Dimeth- ylthiazol-2-yl）-2, 5-diphenyltetrazolium bromide （MTT） assay. Flow cytometry was used to measure the cell cycle and apoptosis. The cell cycle was ana- lyzed with propidium iodide staining. Apoptosis was evaluated using the Annexin V-fluorescein iso- thiocyanate/propidium iodide method. Western blotting was used to analyze the expression of es- trogen receptor （ER）-α and ER-13.RESULTS： XHP had growth-inhibitory effects on MCF-7 and MDA-MB231 cells with a half-maximal inhibitory concentration （IC50） of 10.14 mg/mL （MCF-7） and 8.98 mg/mL （MDA-MB231）. Apoptosis was induced to some extent. Certain changes in the ER were caused. Upregulation of ER-a protein was found in MCF-7 cells. ER-β expression in MDA-MB231 cells was increased. Cell-cycle arrest was not observed in the two BC cell lines. ER-β ex- pression in MCF-7 cells was unchanged. No ER-a ex- pression was shown in MDA-MB231 cells. CONCLUSION： These data suggest that XHP can af- fect cell viability and cause apoptosis, but that the cell cycle is not blocked. XHP has a certain impact on ER expression, but its mechanisms of action of anti-13C effects may not be due to regulation of ER expression.
