低浓度雷公藤甲素增强去甲氧柔红霉素杀伤急性髓细胞白血病干细胞的能力  

Low dose triptolide enhancing cytotoxicity of idarubicin in acute myeloid leukemia stem cells

作　　者：何涵[1] 柳约坚[1] 陈菲莉[1] 查洁[1] 周勇[1] 周淑芸[1] 徐兵[1] 

机构地区：[1]南方医科大学南方医院血液科,广州510515

出　　处：《第三军医大学学报》2014年第18期1886-1889,共4页Journal of Third Military Medical University

基　　金：国家自然科学基金(81070425);广东省科技计划项目(2011B031800063)~~

摘　　要：目的探讨低浓度雷公藤甲素(triptolide,TPL)能否增强去甲氧柔红霉素(idarubicin,IDA)杀伤急性髓细胞白血病(acute myeloid leukemia,AML)干细胞的能力及与Nrf2通路的关系。方法流式细胞仪从KG1a细胞株中分选CD34+CD38-亚群,将其作为AML干细胞模型;MTT检测TPL单药组、IDA单药组、TPL+IDA组处理AML干细胞72 h后细胞抑制率和CI指数;Western blot检测IC20浓度的TPL(5 nmol/L)、IC50浓度的IDA(27 nmol/L)单药及上述浓度的TPL联合IDA作用AML干细胞后Nrf2蛋白表达水平的变化;实时荧光定量PCR检测各组处理后Nrf2及其下游基因NQO1、GSR、HO-1的mRNA表达水平的变化。结果 MTT结果显示TPL和IDA单药对AML干细胞具有一定的增殖抑制作用,72 h的IC50值分别为(20.48±1.60)nmol/L和(285.20±13.74)nmol/L;而小剂量TPL(IC20值,5 nmol/L)与不同浓度IDA联合作用于AML干细胞后的增殖抑制作用显著高于IDA单药,IC50值也从IDA单药的(285.20±13.74)nmol/L下降到双药联合(27.01±0.73)nmol/L,差异有统计学意义(P<0.01)。联合作用指数CI值提示两药合用具有强协同作用。Western blot检测结果显示TPL联合IDA处理AML干细胞后Nrf2蛋白表达水平降低。定量PCR检测结果显示,TPL联合IDA处理AML干细胞后Nrf2及其下游基因NQO1、GSR及HO-1的mRNA表达水平均显著下降(P<0.01)。结论低浓度TPL能显著增强IDA对AML干细胞的杀伤作用,其机制可能与下调Nrf2通路相关。Objective To determine of the ability of low dose triptolide（TPL） enhancing the cytotoxicity of idarubicin（IDA） in acute myeloid leukemia（AML） stem cells and its relationship with Nrf2 pathway.Methods The CD34＋CD38-KG1 a cells were isolated from KG1 a cells with flow cytometry and served as an AML stem cell model. The CD34＋CD38-KG1 a cells were subjected to different treatments（ TPL,IDA,and TPL ＋ IDA） and thereafter detected by MTT assay. Western blotting was used to determine the expression changes of Nrf2 after the treatments. RT-PCR was used to detect the mRNA levels of Nrf2 and its target genes including NQO1,GSR and HO-1. Results The proliferation of CD34＋CD38-KG1 a cells was inhibited by TPL and IDA separately with the 72 h IC50 value of 20. 48 ± 1. 60 nmol /L and 285. 20 ± 13. 74 nmol /L,respectively. Low dose TPL（5 nmol /L） plus IDA showed higher cytotoxicity to CD34＋CD38-KG1 cells than IDA alone,with 72 h IC50value of 27. 01 ± 0. 73 nmol /L（ P〈0. 01）. Combination analysis showed synergistic effects of TPL and IDA. Western blot results displayed that Nrf2 expression was down-regulated in the cells treated with TPL combined with IDA. The mRNA expression of Nrf2 and downstream genes including NQO1,GSR,and HO-1 mRNA was decreased after TPL and IDA combined treatment（P〈0. 01）. Conclusion Low dose TPL may significantly enhance the cytotoxicity of IDA in AML stem cells through Nrf2 pathway.

关 键 词：急性髓细胞白血病干细胞 雷公藤甲素 IDA 

分 类 号：R73-361[医药卫生—肿瘤] R733.71[医药卫生—临床医学]