人乳腺癌MCF-7细胞凋亡过程中p53与bcl-2表达的时序性

研究细胞凋亡过程中p53与bcl－2基因表达变化的时序关系，以探索p53调控bcl－2的可能性。方法：选择具有野生型p53的人乳腺癌MCF-7细胞系，用5－Fu为诱导剂诱导细胞凋亡；用Northern杂交及Western印迹法检测细胞凋亡过程中p53与bcl－2表达变化的时序性。结果：p53表达增高出现在bcl－2表达降低之前。结论：p53在时序上具有作为bcl－2基因负调控转录因子的可能性。

THE TIME ORDER OF EXPRESSION OF p53 AND bcl-2 GENES IN THE APOPTOTIC PROCESS OF HUMAN BREAST CANCER CELL LINE MCF-7

Objective: To explore the time order of expression of p53 and bcl-2 genes in the apoptotic process. Methods:To induce apoptosis of human breast cancer cell MCF-7 line, with wild type p53, by 5-fluorouracil (5-Fu). To examine gene expression of p53 and bcl-2 with Northern blotting, and to examine p53 protein with Western blotting. Results: the mRNA level of p53 increased significantly after expeing MCF-7 cells 5-Fu for 6 h, while the bcl-2 mRNA level decreased significantly after expeing MCF-7 cells to 5-Fu for 12 h.Western blotting results showed that the p53 protein increased significantly after 5-Fu treatment for 12 h.Conclusion: Protein and mRNA of p53 increased before the lowering of gene expression of bcl-2. p53 maydown-regulate gene expression of bcl-2.