The combination of green tea and tamoxifen is effective against breast cancer.
Sartippour MR, Pietras R, Marquez-Garban DC, Chen HW, Heber D, Henning SM, Sartippour G, Zhang L, Lu M, Weinberg O, Rao JY, Brooks MN. The combination of green tea and tamoxifen is effective against breast cancer. Carcinogenesis. 2006 Dec; 27(12):2424-33.