肝细胞生长因子在丝裂霉素C诱导胶质瘤细胞凋亡中的作用

Recombinant human hepatocyte growth factor in cellular apoptosis of glioma induced by mitomycin C

目的探讨人类重组肝细胞生长因子(rhHGF)在丝裂霉素C(MMC)诱导人胶质瘤U251细胞凋亡中的作用。方法采用倒置相差显微镜和透射电镜观察细胞凋亡变化,MTT法检测细胞生长抑制率,TUNEL法和流式细胞术(FCM)研究U251细胞凋亡及细胞周期变化,分析不同浓度的rhHGF对低剂量MMC诱导U251细胞凋亡的影响。结果MMC组U251细胞出现细胞凋亡特有的形态学特征,其抑制率和凋亡指数(AI)分别为(43.7±3.2)%和(63.2±3.4)%,较不同浓度的rhHGF加MMC组和空白对照组显著增高(P<0.05)。随着rhHGF浓度的增加,细胞生长抑制率和凋亡指数呈递减趋势。FCM检测结果表明,MMC主要诱导G0/G1期细胞凋亡而出现凋亡峰,凋亡率25.86%;10和20μg/LrhHGF能特异性抑制MMC诱导U251细胞凋亡,凋亡率分别为15.14%和11.12%。结论rhHGF能抑制MMC诱导的U251细胞凋亡,可能与胶质瘤的复发、耐药等临床特性有关。

Objective To investigate the role of recombinant human hepatocyte growth factor in the apoptosis of U251 cells in human glioma induced by mitomycin C （MMC）. Methods The apoptotic changes were observed with invert microscope and eletron microscopy. The inhibition rates of growth were emamined by MTT. The apoptosis and changes in cell cycle were examined by means of TUNEL and flow cytometry. The ability of rhHGF to resist apoptosis induced by a low dose of MMC was also studied. Results The typical characteristics of apoptosis were observed in U251 cells treated with low dose of MMC and the inhibition rate and the apoptotic index （AI） were （43.7±3.2）% and （63.2±3.4）% respectively, much higher than those in the group treated in combination with rhHGF and MMC and in the controls （P〈0.05）. Statistically significant differences of ability of rhHGF to resist apoptosis were observed in different doses. The result of FCM suggested that MMC induced mainly cellular apoptosis in G0/GI phase when an apoptotic peak appeared, with an apoptotic rate of 25.86%. 10 and 20 μg/L rhHGF could inhibit specifically the induction of apoptosis of U251 cells by MMC reducing the apoptotic rates to 15.14% and 11. 12% respectively. Conclusion rhHGF can resist apoptosis of glioma U251 cells induced by MMC, and it may have some relationship with the drug resistance or recurrence ofglioma.