摘要
目的研究慢性髓系白血病(CML)细胞的胞外信号调节激酶(ERK)/丝裂原活化蛋白激酶(MAPK)的表达和法尼基转移酶抑制剂FTI-277抗细胞增生的作用机制。方法以CML细胞系K562细胞、21例初治CML患者和15例正常供髓者骨髓细胞为研究对象,采用MTT法、AnnexinV-FITC法,观察FTI-277对细胞增生和凋亡的影响;应用流式细胞术、Westernblot检测FTI-277对细胞周期、磷酸化ERK1/2(磷酸化P44/42MAPK)和ERK2(P42MAPK)表达的影响。结果CML细胞与正常细胞相比,磷酸化ERK1/2和ERK2表达明显增高。FTI-277对CML细胞的增生抑制及磷酸化ERK1/2的表达下调均呈剂量和时间依赖性,但对ERK2表达及正常细胞的增生无明显影响。FTI-277对CML细胞无明显诱导凋亡作用,但可使细胞阻滞于G2/M期时相。结论CML细胞存在着ERK/MAPK信号途径的过度激活。FTI-277可通过阻断Ras下游ERK/MAPK信号途径、干预细胞周期调控蛋白的表达、使细胞阻滞于G2/M期等机制,抑制CML细胞的恶性增生。
Objective To investigate the expression of extracellular signal-regulated kinase（ERK）/mitogen-activated protein kinase（MAPK） in chronic myeloid leukemia （CML） cells, as well as to explore the mechanisms of farnesyhransferase inhibitor FTI-277 in the treatment of CML. Methods K562 cells, bone marrow mononuclear cells （BMMNCs） from 21 CML patients at diagnosis and 15 normal donors were examined. Cell proliferation and cell cycle were determined by MTT test and Flow cytometry, respectively. The annexinV -FITC/PI double-staining method was performed to evaluate apoptosis in CML cells. The expression levels of phospho-ERK1/2 （phospho-P44/42MAPK） and ERK2 （P42MAPK） were detected by flow cytometry and western blot. Results The expression levels of phospho-ERK1/2 and ERK2 in CML cells were higher than those in normal cells. FTI-277 inhibited proliferation and phospho-ERK1/2 expression of CML cells in a time-dose dependent manner. However, this inhibitor did not display obvious toxicity toward normal cells and did not modulate ERK2 expression. Treatment of CML cells with FH-277 couldn＇t induce apoptosis but resuited in G2/M block . Conclusion Constitutive activation of ERK/MAPK was observed in CML cells. FTI- 277 exhibited substantial growth inhibition of CML cells by inhibiting the ERK/MAPK pathway, targeting other proteins famesylation and resulting in cell-cycle block.
出处
《白血病．淋巴瘤》
CAS
2006年第3期170-173,共4页
Journal of Leukemia & Lymphoma
