Oolong Tea Extract Induces DNA Damage and Cleavage and Inhibits Breast Cancer Cell Growth and Tumorigenesis

Abstract

Background/Aim: Breast cancer is the most prevalent and devastating malignant disease among women worldwide. Green tea has been extensively studied for its anti-cancer effects, however, existing literature on the correlation of other types of tea with breast cancer is very limited. Materials and Methods: We used six different breast cancer cell lines (ER⁺, PR⁺ or HER2⁺ and triple-negative), treated under different concentrations of green, oolong, black and dark tea extracts, and determined their biological effects. Results: We determined cell viability, observed the changes of cell morphology, measured DNA damage and cleavage, and analyzed the effect on soft agar colony formation and growth. Conclusion: Oolong tea, same as green tea, can induce DNA damage and cleavage, play an inhibitory role in breast cancer cell growth, proliferation and tumorigenesis, and was a great potential as a chemo-preventive agent against breast cancer.