5-氮杂-2’-脱氧胞苷和4-苯基丁酸对慢性粒细胞白血病细胞的miR-196b表达水平有协同作用

5-Aza-2'-deoxycytidine and 4-phenylbutyric acid exert a cooperative effect on the expression of miR-196b in chronic myeloid leukemia cells

目的探讨慢性粒细胞白血病细胞中影响miR-196b表达水平的表观遗传学因素。方法分别采用DNA甲基化转移酶抑制剂5-氮杂-2’-脱氧胞苷(5-Aza-2’-dc)、组蛋白去乙酰化酶抑制剂4-苯基丁酸(PBA)和两者联合处理K562细胞,采用实时定量PCR(Real-time PCR)检测miR-196b的表达水平变化。结果 PBA的半数抑制浓度为1.58mmol/L。和正常人骨髓细胞miR-196b的表达水平相比,Aza组、PBA组和阴性对照组miR-196b的表达水平显著降低且基本一致,Aza+PBA组miR-196b的表达水平和正常人表达水平基本一致。结论单独使用5-Aza-2’-dc或PBA不能使K562细胞中miR-196b的表达恢复正常,两者联合使用共同处理K562细胞,可使miR-196b的表达恢复正常,表明K562细胞中miR-196b的表达水平和基因组甲基化及组蛋白乙酰化均有关系。

Objective To study if 5-Aza-2’-deoxycytidine along or together with 4-phenylbutyric acid could affect miR-196b expression levels in chronic myeloid leukemia cells .Methods K562 cells were treated with DNA methylation inhibitor 5-Aza-2’-deoxycytidine, histone deacetylase inhibitors 4-phenylbutyric acid separately and the combined treatment with both of them, then expression levels of miR-196b were detected using Real-time PCR.Results The half inhibition concentration of 4-phenylbutyric acid was 1.58mmol/L.Comparing with the expression level of miR-196b in normal human bone marrow cells, the expression levels of miR-196b were significantly lower in Aza group , PBA group and negative control cells and nearly consistent among three groups , and as high as normal cells in combined treatment group . Conclusion The expression level of miR-196b in K562 cells could not return to normal treated with 5-Aza-2 ’-deoxycytidine or 4-phenylbutyric acid separately , while could restore normal when treated with both agents , indicating that miR-196b expression level in K562 cells is related with both DNA methylation and histone acetylation .