下调HDAC6促进人白血病细胞K562凋亡的实验研究

Down-regulation of HDAC6 Expression Promotes Apoptosis of Human Leukemia K562 Cells

目的:研究组蛋白去乙酰化转移酶6(Histone deacetylase 6,HDAC6)对人白血病细胞促凋亡作用及其机制。方法:采用siRNA干扰技术抑制HDAC6基因的表达;应用RT-PCR和Western blot分别检测白血病细胞中HDAC6和相关信号通路蛋白的表达;流式细胞术和Hoechest染色检测K562细胞的凋亡及形态改变。结果:与健康志愿者的外周单核细胞和骨髓基质细胞株比较,白血病细胞系的HDAC6表达量均明显增高(P <0. 05);流式细胞术和Hoechest染色显示,干扰HDAC6基因后K562细胞凋亡率增加,且呈凋亡形态发生改变; Western blot显示,干扰HDAC6能增加Bax/Bcl-2的比例和cleaved Caspase-3的表达,并激活MAPK、ATK、ERK信号通路。结论:干扰HDAC6促进人白血病细胞K562细胞的凋亡,其凋亡的机制可能与激活MAPK信号通路有关。

Objective: To study the promoting-apoptosis effect of HDAC6 on the human leukemia cells and its mechanism.Methods: The siRNA interference technology was used to inhibit the expression of HDAC6 gene,the RTPCR and Western blot were used to detect the expression of HDAC6 and related signal pathway proteins respectively,the flow cytometry and Hoechest staining were used to detect the apoptosis and morphology changes of K562 cells.Results: Compared with the periphal blood monocyte and bone marrow stromal cells of healthy volunteers,the expression level of HDAC6 in leukemia cell lines was up-regulated significantly ( P<0.05) ; the flow cytometry and Hoechest staining showed that after interference of HDAC6 gene,the apoptosis of K562 cells increased,moreover the cell morphology was changed; the Western blot detection showed that the interfering HDAC6 increased BAX /BCL-2 ratio and cleaved caspase 3 expression,and activated the MAPK,ATK,ERK signaling pathway.Conclusion: The interferance of HDAC6 can promote the K562 cell apoptosis,its mechanism may relate with activation of MAPK signaling pathway.