bFGF促进肝癌Bel-7402细胞增殖的信号转导机制

目的:分析肝癌细胞系Bel-7402中Ras-Raf-ERK1/2途径介导的bFGF对细胞周期素E(cyclinE)表达及细胞增殖的影响,以探讨肝癌细胞增殖的信号转导机制。方法:bFGF处理后用流式细胞术检测细胞增殖情况;Western印迹检测ERK1/2激酶的活化;RT-RCR方法检测cyclinE的基因表达。结果:FCM结果表明bFGF诱导细胞进入S期(27.49%±0.72%→42.45%±1.06%);bFGF时、量效依赖性地诱导Bel-7402细胞ERK1/2活性增高和cy-clinEmRNA表达。25ng/mlbFGF作用Bel-7402细胞10minERK1/2活性达高峰为对照组的3.84倍,作用8h后cyclinEmRNA表达达高峰为对照组的5.15倍;MEK1抑制剂PD98059可抑制bFGF的这些作用。结论:Ras-Raf-ERK1/2途径介导bFGF对cyclinEmRNA表达的诱导进而促进Bel-7402细胞的细胞周期进程,在肝癌增殖过程中bFGF信号转导发挥了重要的作用。

The Signal Transduction Mechanism of bFGF for Promotion of the Proliferation in Bel-7402 Liver Cancer Cell

Objective: To analyze Ras-Raf-ERK1/2-mediated functions of bFGF on the mRNA expression of cyclin E and proliferation in Bel-7402 liver carcinoma cell and to investigate the signal transduction mechanism of proliferation in liver cancer. Methods: After treatment with bFGF, the cellcycle distribution, ERK1/2 activity and the mRNA expression of cycln E of Bel-7402 cell were studied using FACScan flow cytometry, Western blotting and RT-PCR respectively. Results: FCM analysis showed that bFGF induced S-phase entry (27.49± 0.72%→42.45± 1.06%) and bFGF, in a time anddose-dependence way, induced ERK1/2 activity and cyclin E mRNA expression. Treated cells with 25ng/ml bFGF, ERK1/2 activity and cyclin E mRNA expression reached the peak at 10min(3.84-fold in-duction) and 8h (5.15-fold induction), respectively. All the effects of bFGF were inhibited by PD98059, the inhibitor of MEK1. Conclusion: In Bel-7402 liver cancer cell, Ras-Raf-ERK1/2 path-way mediates the induction of cyclin E mRNA and the promotion of cell cycle resulted from bFGF. The bFGF signal transduction might play important roles in proliferation of liver cancer.