铁剥夺和铁超负荷对白血病细胞株HL-60凋亡的影响机制

The influence of iron deprivation and rich iron on the apoptosis of human Leukemia-60 cells

目的探讨铁剥夺和铁超负荷对白血病细胞株HL-60细胞凋亡的影响及其机制,为临床采用铁剥夺策略治疗或辅助治疗白血病提供理论依据。方法在HL-60细胞培养基中分别加入不同浓度的去铁胺(DFO)或三氯化铁(FeCl3),造成细胞内铁剥夺或铁超负荷状态,采取噻唑蓝(MTT)法、DNA原位末端标记染色法(TUNEL)、免疫组化法检测铁剥夺和铁超负荷状态下HL-60细胞活力、凋亡率、细胞色素C(Cyt C)阳性细胞率。结果 DFO组细胞活力呈明显下降趋势,凋亡率呈显著上升趋势;FeCl3组细胞活力和凋亡率与对照组相比呈下降趋势;DFO组细胞胞浆内Cyt C阳性细胞率与对照组相比明显升高;而FeCl3组细胞浆内Cyt C阳性细胞率与对照组相比无明显差异。结论铁剥夺可促进线粒体释放Cyt C,诱导HL-60细胞凋亡;铁超负荷对线粒体释放Cyt C无直接影响作用。

Objective To explore the influence and mechanism of iron deprivation and rich iron on the apoptotic process of human Leukemia-60 （HL-60） cells, and provide the theoretical basis for the clinical therapy. Methods HL-60 ceils were cultivated with different concentration of DFO and FeCl3 to establish intracellular iron-deprivated and rich-iron states. Cell viability, apoptotic rate and the positive rate of Cyt C were detected by MTT, TUNEL and immunohistochemistry. Results The cell viability in DFO-treated group decreased, while the apoptotic rate increased dramatically. In contrast, an opposite result was obtained in FeCl3-treated group. The positive rate of Cyt C in DFO-treated group was elevated, but no difference was found in FeCl3-treated group. Conclusions Iron deprivation induces apoptosis of HL-60 cells by releasing Cyt C from mitochondria, while rich iron has no direct impact on it. The mechanism of HL-60 cell proliferation might be related with the apoptosis-related genes in the upstream of the mitoehondrial pathway.