泛素异肽酶抑制剂Ⅰ抑制人类白血病K562细胞增殖和诱导凋亡的研究

摘要

Objective To investigate the effects of ubiquitin isopeptidase inhibitor Ⅰ on proliferation and apoptosis of human leukemic K562 cells.Methods Human leukemic K562 cells were treated with different concentration of ubiquitin isopeptidase inhibitor Ⅰ.Cell proliferation was monitored by MTT assay.Cell apoptosis was analyzed by flow cytometry after Annexin V/PI staining,and mRNA expression levels of bcl-2,bax and Caspase-3 were quantified by reverse transcription-polymerase chain reaction (RT-PCR).Results MTT assay showed that the proliferation of K562 cells was markedly inhibited by ubiquitin isopeptidase inhibitor Ⅰ in a time-and-dose dependent manner.The Annexin V positive rate of K562 cells after treatment with ubiquitin isopeptidase inhibitor Ⅰ was significantly increased by FCM analysis (P ＜ 0.05).The early apoptosis rate of K562 cells treated with 100 nmol/L ubiquitin isopeptidas inhibitor Ⅰ by 72 h,was obviously increased compared to control cells [(15.4±1.3) ％ vs (4.1±0.9) ％,P ＜ 0.01].The mRNA levels of Caspase-3 and bax were up-regulated and bcl-2 was down-regulated after treated with ubiquitin isopeptidase inhibitor Ⅰ,and the differences were statistically significant from control cells (P ＜ 0.05).Conclusion Ubiquitin isopeptidase inhibitor Ⅰ has inhibitory effect on proliferation and inductive effect on apoptosis of K562 leukemia cells,implying its possible application in treating leukemia.%目的 探讨泛素异肽酶抑制剂Ⅰ对人类白血病K562细胞增殖及凋亡的影响.方法 K562细胞经不同浓度的泛素异肽酶抑制剂Ⅰ处理,四甲基偶氮唑蓝(MTT)法检测其对K562细胞增殖的抑制作用,AnnexinV FITC/PI染色流式细胞术检测细胞凋亡率,反转录-定量聚合酶链反应(RT-PCR)检测bcl-2、bax和凋亡特异性酶Caspase-3表达水平.结果 泛素异肽酶抑制剂Ⅰ能抑制K562细胞的增殖,随作用时间的延长和浓度的增加抑制作用增强.经100 nmol/L泛素异肽酶抑制剂Ⅰ处理72 h,K562细胞早期凋亡率为(15.4±1.3)％,与对照组的(4.1±0.9)％相比明显上升(P＜0.01).用100 nmol/L的泛素异肽酶抑制剂Ⅰ处理K562细胞72 h后,Caspase-3和bax mRNA表达增高,bcl-2表达降低,与对照组相比差异有统计学意义(P＜0.05).结论 泛素异肽酶抑制剂Ⅰ对K562细胞具有抑制增殖和诱导凋亡的作用,提示其可能用于治疗白血病.