慢性粒细胞性白血病中SHIP1基因的表达变化及机制探讨

目的观察SHIP1基因在慢性粒细胞性白血病(CML)患者中的表达变化,并通过特异性小干扰RNA(siRNA)封闭K562细胞株BCR-ABL基因的表达,探讨BCR-ABL基因表达对SHIP1基因的影响。方法应用RQ-PCR方法检测CML患者骨髓、正常人外周血白细胞及白血病细胞株K562中SHIP1基因表达的差异。另取K562细胞分为3组:空白对照组(不加任何干扰成分);非特异性siRNA处理组(加非特异性siRNA);特异性siRNA处理组(加入特异性siRNA封闭BCR/ABL融合基因),应用RQ-PCR及Western blot方法分别检测3组中BCR/ABL、SHIP1基因的mRNA及其相应蛋白P210(BCR/ABL编码)、P145(SHIP1基因编码)的表达,并比较各组中表达水平的变化。结果CML患者骨髓白细胞和K562细胞中SHIP1基因的表达明显低于正常人的外周血白细胞。特异性siRNA处理组中BCR-ABL基因mRNA和P210蛋白的表达水平明显下降,SHIP1基因mRNA和P145蛋白表达水平随BCR-ABL表达下降而增加;非特异性siRNA处理组与空白组相比无明显差异。结论CML患者SHIP1基因的表达低于正常人;特异性siRNA能够抑制BCR-ABL基因的表达;BCR-ABL基因能抑制SHIP1基因及其蛋白表达。

Expression changes of SHIP1 and the possible mechanism in the chronic mylogenous leukemia

Objective To explore the expression changes in SHIP1 gene in patients with chronic granulocytic leukemia (CGL), healthy volunteers and the K562 cells (one of human CGL cell lines), and to explore the effects of BCR/ABL expression in K562 cells on the SHIP1 gene by blocking the BCR/ABL expression in K562 cells with a specific siRNA. Methods The expression levels of SHIP1 mRNA in leukocytes of the patients with CGL, healthy controls and K562 cells were assessed with RQ-PCR. In addition, K562 cells were divided into three groups: control group (untreated), non-specific interference group (treated with non-specific siRNA), and specific interference group (treated with specific siRNA to block BCR/ABL gene). RQ-PCR and Western blotting were employed to examine the expression level of mRNA and protein (P210 and P145) of BCR/ABL and SHIP1 genes. Results The mRNA expression of SHIP1 in CGL patients and K562 cells was significantly lower than that of the healthy controls. The expression of BCR/ABL gene was down-regulated, while SHIP1 gene up-regulated, in the specific interference group. No statistical significant difference was found between the non-specific interference group and the control group. Conclusions The mRNA expression of SHIP1 is lower in patients with CGL than in the healthy control. The specific siRNA can block the expression of BCR-ABL and further suppress the expression of SHIP1.