Synergism of Green Tea Polyphenols and Phenanthrene Promotes the Death of Human Lung Adenocarcinoma Cell Line SPC-A-1

Abstract

Green tea polyphenols (GTP), an anticarcinogen in tea leaves, can provide protection against various cancer types induced by polycyclic aromatic hydrocarbons (PAHs). However, current research about mutual effects has hardly focused on phenanthrene (PA), which is a dominant PAH with low toxicity detected in environment and many commercial tea samples. GTP and PA may be absorbed concurrently by the human body when people drink tea. In order to reveal the relation between intake of smoked tea and enhancement of cancer risk, in this study, growth inhibition, apoptosis, and cell cycle were assayed in human lung adenocarcinoma cell line SPC-A-1, and the interaction effects of GTP and PA was statistically analyzed. The results showed that GTP and PA inhibited cell growth in a concentration-dependent manner; their interaction significantly reduced the inhibition and affected the cell cycle; the final combination of PA and GTP exhibited a synergistic inhibition which caused cell death more acutely, and the cell cycle was arrested at S-phase, which means GTA could reduce the cancer risk even with drinking smoked tea in low concentration of PA.

Key Words:

• cancer cell
• green tea polyphenols
• phenanthrene
• synergism