GSK-3β在结直肠癌细胞凋亡中的作用

Study on the Glycogen Synthase Kinase-3β in 5-Fluorouracil Induced Apoptosis in Colorectal Carcinoma Cell Line Colo 320

目的探讨糖原合成酶激酶 3β(GSK 3β)在结直肠癌细胞凋亡中的作用机制。 方法以化疗药物 5 -氟尿嘧啶 (5 Fu)诱导结直肠癌细胞colo32 0凋亡 ,应用AnnexinV/PI双染流式细胞术检测细胞凋亡百分率 ,用Westernblot检测凋亡细胞总GSK 3β ,分离细胞核与细胞浆蛋白 ,分析细胞浆 /核GSK 3β和转录因子NF κB水平。结果Colo32 0细胞凋亡比例随 5 Fu作用剂量增加和时间延长显著提高。对照组细胞GSK 3β和NF κB主要位于胞浆中 ,凋亡组细胞总GSK 3β水平没有明显改变 ,但发生了细胞浆到细胞核的迁移。结论GSK 3β以细胞浆 /核迁移方式参与并促进了 5 Fu诱导的结直肠癌细胞凋亡 ,其机制可能是通过抑制转录因子NF κB向核中移位 ,从而阻断NF

Objective To observe the potential roles and possible mechanisms of glycogen synthase kinase-3β in the regulation of apoptosis signal transduction in colorectal carcinoma cells. Methods Apoptosis in colo320 cells was induced by 5-fluorouracil (5-Fu) which is a chemo-therapy agent in colorectal carcinoma treatment. The Anne- xin-V/PI double staining analysis by flow cytometry was used to evaluate apoptosis. Total cytosol and nuclear protein levels of NF-κB and GSK-3β were analyzed by Western blot. Results 5- FU treatment caused time-and concentration-dependent increases of colo320 in apoptotic cells. GSK-3β and NF-κB were predominantly located in the cytosol. 5-Fu treatment caused a marked increase in nuclear GSK-3β while the level and distribution of NF-κB did not change. Conclusion GSK-3β may facilitate apoptosis induced by 5-Fu in colorectal carcinoma cells through relocation from cytosol to nucleus in the apoptosis process. Its downstream effect may be mediated by NF-κB. GSK-3β might exert its apoptosis prone effect by preventing relocation of NF-κB from cytosol to nucleus.