Abstract

Background: The aim of the present study was to investigate the apoptotic effect of two highly consumed beverages, green tea and caffeine on squamous cell carcinoma, through investigation of p53, bcl2 and caspase-3 expression. Methods: Human laryngeal carcinoma cell line (HEp-2) was treated with 120µg/ml green tea and with 720µg/ml caffeine for 48 and 72 hours. Real-time PCR quantified the mRNA expression level of p53, bcl2 and caspase-3 was done. Results: Student t-test comparing the effect of green tea and caffeine on HEp-2 cell line, treated with different time lengths, revealed that green tea significantly increased mRNA expression of p53 after 48 and 72 hours when compared to caffeine at the same time durations (0.5295±0.1045 vs. 0.1783±0.0745, p=< 0.001 after 48 hours)(0.9609±0.1314 vs. 0.1774±0.0 502, p=< 0.001 after 72 hours). Green tea significantly decreased mRNA expression of bcl2 only after 72 hours when compared to caffeine at the same duration (0.2748±0.1011 vs. 0.4367±0.2067, p= 0.0234). Green tea significantly increased mRNA expression of caspase-3 only after 72 hours when compared to caffeine at the same duration (1.464±0.422 vs. 0.75380. 3704, p= 0.002). Conclusion: Both green tea and caffeine exerted an apoptotic effect on squamous cell carcinoma; however green tea had a more profound effect when compared to caffeine. Extending the time of treatment to 72 hours with green tea and caffeine induced more apoptosis.