MCYCLIN B1 IN GAMMA IRRADIATED & TRANSFORMED CELLS: CAFFEINE OR STAUROSPORINE RX

用流式细胞术比较咖啡因和 星状孢子素对辐射诱导的G2期阻滞和细胞周期蛋白B1的影响 正常人皮肤成纤维细胞和HeLa细胞的表达 在6.0Gy伽马辐射之后。咖啡因和星形孢子素 同样有效地减弱两种辐射引起的 细胞周期蛋白B1的表达与细胞周期G2的延长 HeLa细胞群体不同步。咖啡因对一种 照射后的HSF细胞有相似的程度，但星状孢子素 在释放辐射诱导的G2阻滞方面无效，但确实做到了 降低这些细胞群体中细胞周期蛋白B1的水平。这些结果 提示星孢菌素作用于细胞周期的不同途径 控制正常和转化的细胞对辐射的反应。

Flow cytometry was used to compare effects of caffeine or staurosporine on the radiation-induced G2-phase arrest and cyclin B1 expression in normal, human skin fibroblast (HSF) cells and HeLa cells following 6.0 Gy of gamma radiation. Caffeine and staurosporine were equally effective in attenuating both radiation induced increase in cyclin B1 expression and the prolongation of G2 in synchronous and asynchronous HeLa cell populations. Caffeine was also effective to a similar extent in irradiated HSF cells but staurosporine was ineffective in releasing the radiation-induced G2 block but did decrease cyclin B1 levels in those cell populations. These results suggest that staurosporine acts on different pathways of cell cycle controlling normal and transformed cells in response to radiation.