Komatsu K, Tauchi H, Yano N, Endo S, Matsuura S, Shoji S
Department of Radiation Biology, Hiroshima University, Japan.
Cancer Lett. 1997 Jan 30;112(2):135-9. doi: 10.1016/s0304-3835(96)04555-7.
The anticarcinogenic activity of a major component of green tea, (-) epigallocatechin gallate (EGCg) was examined by using the radiation-induced oncogenic transformation in C3H10T1/2 cells. EGCg substantially suppressed the radiation-induced transformation so that the transformation frequency with 15 microM of EGCg was reduced nearly to spontaneous levels. This effect of EGCg was in a dose-dependent manner and significant suppression of transformation was observed even in treatment of cells with 5 microM of EGCg concentration where the cytotoxicity was mild. The inhibitory effect of EGCg was maximal when it was present during the entire incubation period. However, neither treatment prior to nor concurrent with radiation was effective, suggesting that EGCg action is mainly involved in the promotional stage of C3H10T1/2 cell transformation.
利用C3H10T1/2细胞中的辐射诱导致癌转化，检测了绿茶主要成分（-）表没食子儿没食子酸酯（EGCg）的抗癌活性。EGCg显著抑制了辐射诱导的转化，因此15微摩尔EGCg处理后的转化频率几乎降至自发水平。EGCg的这种作用呈剂量依赖性，即使在5微摩尔EGCg浓度处理细胞时（细胞毒性轻微）也观察到对转化的显著抑制。当EGCg在整个孵育期都存在时，其抑制作用最大。然而，辐射前或辐射时处理均无效，这表明EGCg的作用主要涉及C3H10T1/2细胞转化的促进阶段。
