Mcl-1基因在HL-60细胞对全反式维甲酸耐药机制中的作用

目的探讨髓系白血病-1(Mcl-1)基因在HL60细胞对全反式维甲酸(ATRA)耐药中的作用。方法采用少量、递增、反复ATRA诱导HL-60细胞,建立ATRA耐药细胞系HL60/ATRA;利用鸡尾酒法制备Mcl-1基因的小片段干扰RNA(SmallinterferenceRNA,siRNA),并通过脂质体介导将其导入HL60/ATRA细胞;Westernblot检测Mcl-1蛋白在细胞中的表达;MTT实验、NBT还原反应实验、TUNEL免疫组化染色法分别检测细胞的增殖、分化和凋亡情况。结果HL60/ATRA细胞Mcl1蛋白相对灰度值为0.624±0.127,较野生型HL60细胞(相对灰度值为0.162±0.127)明显高表达,并可耐受100nmol/L的ATRA,而不发生分化、凋亡凋亡率为(1.0±0.5)%];Mcl1siRNA导入HL60/ATRA细胞后,Mcl1蛋白表达下调(相对灰度值为0.267±0.086),恢复对ATRA的敏感性凋亡率为(18.5±4.5)%]。结论Mcl1基因可能参与了HL60细胞ATRA耐药的形成;抑制Mcl-1基因可能成为一种新的逆转ATRA耐药的策略。

The effects of Mcl-1 gene in ATRA-resistant HL-60 cell

OBJECTIVE: To investigate the role of Mcl-1 gene in resistance of all-trans retinoic acid (ATRA) of leukemia cells. METHODS: Long-term, intermittent and repetitive exposure of HL-60 cells to ATRA was used to establish a multidrug-resistance cell line (HL-60/ATRA). HL-60/ATRA cells were transfected with Mcl-1 small interference RNA (siRNA) by Lipofectamine 2000. Western blot was used to detect the expression of Mcl-1. The proliferation, apoptosis and differentiation were evaluated by MTT assay, in situ nick end-labeling (TUNEL) and NBT assay, respectively. RESULTS: The HL-60/ATRA could keep its undifferentiated and proliferative status to a high concentration of ATRA (100 nmol/L) with highly expressed Mcl-1 protein (relative grey scale 0.624 +/- 0.127). Mcl-1 gene knockdown by siRNA (relative grey scale 0.267 +/- 0.086) could reverse the resistance of ATRA of HL-60/ATRA by inhibiting proliferation, and inducing differentiation and apoptosis apoptosis rate (18.5 +/- 4.5)%]. CONCLUSION: Mcl-1 gene might be involved in ATRA resistance in HL-60 cells and inhibiting its expression could be a new approach to ATRA resistance reversion.