MLL在HOXA10表达调控中作用的实验研究  

Mixed lineage leukemia plays a critical role in estrogen-mediated regulation of HOXA10 in acute myelocytic leukemia cells

作　　者：姚婕[1] 方立超[1] 郑峻松[1] 

机构地区：[1]第三军医大学医学检验系临床检验学教研室,重庆400038

出　　处：《第三军医大学学报》2013年第17期1797-1800,共4页Journal of Third Military Medical University

基　　金：国家自然科学基金(81000225)~~

摘　　要：目的通过研究在急性髓性白血病细胞中HOXA10表达调控机制,探讨HOXA10调控作为AML防治新靶点的可能性。方法以不同剂量雌二醇(E2)在不同时间点刺激急性粒细胞白血病细胞株(HL-60),以不刺激的HL-60细胞作参照应用RT-PCR检测HOXA10基因表达活性的差异明确E2对HOXA10表达的活化作用,并在E2刺激下以反义寡核苷酸转染技术分别敲除ERα、ERβ和MLLs(MLL1-4)后再检测HOXA10 mRNA和蛋白表达的变化确定哪一种雌激素受体的活化与HOXA10的表达相关,哪一种MLL对HOXA10表达有调控作用。以ChIP实验检测MLL和HOXA10的相互作用,再以Western blot检测E2刺激前后组蛋白H3K4甲基化状态以明确MLL是否通过表观遗传学途径调控HOXA10的表达。结果在E250 nmol/L 6 h刺激下HOXA10表达明显升高,ERα和ERβ反义寡核苷酸转染后HOXA10表达均有下降,MLL1表达沉默时HOXA10表达明显降低(P<0.05),MLL1可以结合到HOXA10启动子上的ERE区域而组蛋白H3K4甲基化状态在E2刺激后明显高于刺激前(P<0.05)。结论急性髓性白血病细胞的HOXA10基因表达受MLL1蛋白调控,可能为急性髓性白血病的致病机制分析提供了一个新的方向,MLL1介导的HOXA10表达的改变有可能成为急性髓性白血病的防治新靶点。Objective To investigate the expression of HOXA10 in acute myelocytic leukemia cells, and to find the regulating mechanism of HOXA10 expression in acute myelocytic leukemia cells. Methods RT-PCR and Western blotting were applied to detect HOXA10 mRNA and protein expression in acute myelocytic leukemia HL-60 cells with knockdown of ERα, ERβ and mix lineage leukemia （MLLs） （MLL1-4）, respectively, and with or without treatment of estradiol （E2）. ChIP was used to check the interaction between MLL and HOXA10, and Western blotting was used to check the methylation status of histone H3K4. Results E2 could elevate HOXA10 expression through activation of ERα and ERβ. HOXA10 expression could be down-regulated by MLL1 knockdown. MLL1 could bind to the ERE region on HOXA10 promoter sequence. Conclusion This study may provide a new direction to study the pathogenic mechanism of acute myelocytic leukemia, and indicates that MLL1 can be a potential target for prevention and treatment of leukemia.

关 键 词：HOXA10 混合系白血病基因 雌激素受体 急性髓性白血病 

分 类 号：R363.21[医药卫生—病理学] R394.3[医药卫生—基础医学]