Steve Harakeh, Mona Diab-Assaf, Rania Azar, Hani Mutlak Abdulla Hassan, Safwan Tayeb, Khalil Abou-El-Ardat, Ghazi Abdullah Damanhouri, Ishtiaq Qadri, Adel Abuzenadah, Adeel Chaudhary, Taha Kumosani, Aleksandra Niedzwiecki, Mathias Rath, Haitham Yacoub, Esam Azhar, Elie Barbour
Asian Pacific journal of cancer prevention: APJCP (Impact Factor: 1.27). 01/2014; 15(3):1219-1225.
Epigallocatechin-3-gallate (EGCG) is the most abundant polyphenol molecule from green tea and is known to exhibit antioxidative as well as tumor suppressing activity. In order to examine EGCG tumor invasion and suppressing activity against adult T-cell leukemia (ATL), two HTLV-1 positive leukemia cells (HuT-102 and C91- PL) were treated with non-cytotoxic concentrations of EGCG for 2 and 4 days.
Proliferation was significantly inhibited by 100 μM at 4 days, with low cell lysis or cytotoxicity. HTLV-1 oncoprotein (Tax) expression in HuT- 102 and C91-PL cells was inhibited by 25 μM and 125 μM respectively. The same concentrations of EGCG inhibited NF-kB nuclearization and stimulation of matrix metalloproteinase-9 (MMP-9) expression in both cell lines. These results indicate that EGCG can inhibit proliferation and reduce the invasive potential of HTLV-1- positive leukemia cells. It apparently exerted its effects by suppressing Tax expression, manifested by inhibiting the activation of NF-kB pathway and induction of MMP-9 transcription in HTLV-1 positive cells.