硼替佐米对白血病细胞株HEL抑制作用的初步探讨

Study of inhibitory effect of bortezomib on leukemia cell line HEL

目的 探讨硼替佐米单独或联合化疗药物对急性白血病细胞株HEL生长的影响及其机制。方法MTT法检测药物对HEL的生长抑制效应，流式细胞术检测细胞周期变化及凋亡，Westernblotting检测凋亡及细胞周期相关蛋白表达。结果硼替佐米对HEL细胞的生长抑制作用呈浓度依赖关系，其半数抑制浓度（IC50）为7．15nmol／L；硼替佐米联合化疗药物明显增强抑制HEL细胞生长；流式细胞术检测可见时问依赖性的G2／M周期阻滞；Western blotting检测显示bcl-2表达下降，bax、p27表达增高，联合用药时具有相加效应，但不管是单独或联合用药，p53蛋白的表达均无明显改变。结论硼替佐米可能是一种有效治疗急性白血病的药物，与柔红霉素联合应用有更强的抑制肿瘤细胞生长和诱导其凋亡的作用，其机制可能与bcl-2，bax及p27蛋白的调节有关，是非p53依赖性的。

Objective To explore the effects of proteasome inhibitor bortezomib alone and in combination with chemotherapeutic agents in acute leukemia cell line HEL. Methods Tumor cell growth inhibition and apoptosis was measured by MTF assay and FACS analysis, respectively. Apoptosis- and cell eycle-associatd protein expression levels were measured by Western blotting assay. Results Bortezomib induced the suppression of tumor cell growth and apoptosis in a dose-dependent manner with an inhibitor concentration ICso values 7.15 nmol/L in acute leukemia cell line HEL. Further combination treatment with doxorubicin or cytarabine increased tumor cell growth suppression in acute leukemia cell line, as compared to single drug treatment alone. Bortezomib caused an increase in G2/M in a time-dependent manner. Bortezomib alone and in combination with chemotherapeutic agents treatment increased the bax and p27 expression and decreased the bcl-2 expression even without influencing p53 expression levels. Conclusion Bortezomib may be an effective therapeutic drug for patients with acute leukemia. Combining bortezomib with doxorubiein might be more effeetive for displaying tumor cell growth inhibitor effects in acute leukemia cells through regulation of bcl-2, bax and P27 nroteins and indenendent of P53 status.