Inhibitory effects and molecular mechanisms of selenium-containing tea polysaccharides on human breast cancer MCF-7 cells.

Abstract

Dietary supplementation of selenium-enriched tea is known to have an anticancer health benefit. This study was to investigate the inhibitory effect of selenium-containing tea polysaccharides (Se-GTPs) from a new variety of selenium-enriched Ziyang green tea against human MCF-7 breast cancer cells. Se-GTPs dose-dependently exhibited an effective cell growth inhibition with an IC(50) of 140.1 μg/mL by inducing MCF-7 cancer cells to undergo G2/M phase arrest and apoptosis. The blockade of cell cycle was associated with an up-regulation of p53 expression, but not CDK2. Se-GTPs clearly triggered the mitochondrial apoptotic pathway, as indicated by an increase in Bax/Bcl-2 ratio and subsequent caspase-3 and caspase-9 activation. It was also found that the generation of intracellular ROS is a critical mediator in Se-GTPs-induced cell growth inhibition. These findings suggest that Se-GTPs may serve as a potential novel dietary agent for human breast cancer chemoprevention.

• Authors: Nianwu He, Xiaolong Shi, Yan Zhao, Lingmin Tian, Dongying Wang, Xingbin Yang
• Journal: Journal of agricultural and food chemistry (J Agric Food Chem) Vol. 61 Issue 3 Pg. 579-88 (Jan 23 2013) ISSN: 1520-5118 [Electronic] United States
• PMID: 23270479 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents, Phytogenic
• BAX protein, human
• Polysaccharides
• Reactive Oxygen Species
• Tea
• Tumor Suppressor Protein p53
• bcl-2-Associated X Protein
• CDK2 protein, human
• Cyclin-Dependent Kinase 2
• CASP3 protein, human
• CASP9 protein, human
• Caspase 3
• Caspase 9
• Selenium

Topics

• Antineoplastic Agents, Phytogenic (pharmacology)
• Apoptosis (drug effects)
• Caspase 3 (metabolism)
• Caspase 9 (metabolism)
• Cell Cycle (drug effects)
• Cell Proliferation (drug effects)
• Cyclin-Dependent Kinase 2 (metabolism)
• Female
• Humans
• Inhibitory Concentration 50
• MCF-7 Cells
• Mitochondria (drug effects)
• Polysaccharides (pharmacology)
• Reactive Oxygen Species
• Selenium (pharmacology)
• Signal Transduction
• Tea (chemistry)
• Tumor Suppressor Protein p53 (metabolism)
• Up-Regulation
• bcl-2-Associated X Protein (metabolism)