摘要目的：分析siRNA介导独立生长因子1（ GFI?1）基因沉默对不典型慢性髓细胞白血病（ aCML） NT1细胞生长和增殖的影响。方法采用细胞转染试剂Lipofectamine 2000，将siRNA导入对数生长期的NT1细胞，实验分为空白对照组（加入PBS和脂质体复合物）、阴性对照组（加入阴性干扰序列和脂质体复合物）和GFI?1基因干扰组（加入针对GFI?1的干扰序列和脂质体复合物）。采用实时荧光定量PCR法检测GFI?1 mRNA的表达水平，Western blot法检测GFI?1蛋白的表达水平，四甲基偶氮唑蓝（ MTT）法检测GFI?1 siRNA对NT1细胞增殖的影响，流式细胞仪检测GFI?1 siRNA对NT1细胞周期的影响。裸鼠移植瘤实验检测GFI?1 siRNA对裸鼠成瘤的影响。结果实时荧光定量PCR检测显示，空白对照组、阴性对照组和基因干扰组的GFI?1 mRNA表达水平分别为1．010±0．005、0．918±0．006和0．367±0．017，基因干扰组与空白对照组和阴性对照组的差异有统计学意义（P＜0．05）。Western blot检测显示，基因干扰组的GFI?1蛋白表达水平明显低于空白对照组和阴性对照组（ P＜0．05）。 MTT法检测显示，空白对照组、阴性对照组和基因干扰组的A值分别为1．193±0．064、1．096±0．049和0．667±0．059，基因干扰组的细胞增殖能力明显低于空白对照组和阴性对照组（P＝0．023）。流式细胞仪检测显示，空白对照组、阴性对照组和基因干扰组的 G0／G1期细胞比例分别为（48．6±3．2）％、（53．3±4．5）％和（66．7±3．8）％，基因干扰组与空白对照组和阴性对照组的差异有统计学意义（P＜0．05）。空白对照组、阴性对照组和基因干扰组的 sub?G1期细胞比例分别为（2．0±3．6）％、（1．9±1．3）％和（8．2±2．5）％，基因干扰组与空白对照组和阴性对照组的差异有统计学意义（P＜0．05）。裸鼠移植瘤实验显示，空白对照组、阴性对照组和基因干扰组裸鼠的肿瘤重量分别为（0．92±0．04）g、（0．83±0．06）g和（0．37±0．02）g，基因干扰组裸鼠的肿瘤重量明显小于空白对照组和阴性对照组（P＜0．05）。结论 siRNA介导GFI?1基因沉默可抑制NT1细胞生长与增殖，可能为aCML的治疗提供新的靶点。

abstractsObjective To investigate the inhibitory effects of RNA interference targeting GFI?1 on growth and proliferation of atypical chronic myelogenous leukemia ( aCML) NT1 cells. Methods NT1 cells were transfected with PBS and liposome complex ( vehicle group) , scrambled siRNA and liposome complex ( negative control, NC group ) , and GFI?1 siRNA and liposome complex ( GFI?1 siRNA group ) , respectively. Real?time quantitative RT?PCR ( qRT?PCR) and Western blot were performed to examine the expression levels of GFI?1 mRNA and protein, respectively. The proliferation abilities of NT1 cells of the three groups were evaluated by MTT assay. The cell cycle in cells of the three groups was analyzed by flow cytometry. Moreover, nude mouse xenograft model was used to detect the tumor formation ability in the three group cells. Results Quantitative real?time PCR data showed that the expression level of GFI?1 mRNA in GFI?1 siRNA group was significantly lower than those of NC group and vehicle group [(0.367±0.017) vs. (0.918±0.006) and (1.010±0.005), respectively, (P<0.05)]. Western blot results showed that the GFI?1 protein expression level in the GFI?1 siRNA group was also significantly reduced, compared with those of the&nbsp;NC group and vehicle group ( P<0.05 for both) . From MTT assay data, the absorbance value of NT1 cells in the GFI?1 siRNA group (0.667±0.059) was significantly lower than those of the NC group (1.096±0.049) and vehicle group (1.193±0.064, P=0.023). Flow cytometry data showed that sub?G1 and G0/G1 phase proportions of the GFI?1 siRNA group were significantly higher than those of the NC and vehicle groups [ sub?G1: (8.2±2.5)% vs. (1.9±1.3)% and (2.0±3.6)%, respectively, (P<0.05);G0/G1:(66.7±3.8)% vs. (53.3±4.5)% and (48.6±3.2)%, respectively, (P<0.05)]. Furthermore, the tumor weight in the GFI?1 siRNA group [(0.37±0.02) g] was significantly lower than those in the NC group [(0.83±0.06) g] and vehicle group [(0.92±0.04) g] (P<0.05). Conclusions RNA interference targeting GFI?1 inhibits the growth and proliferation of NT1 cells, which may provide a new therapeutic target for atypical chronic myelogenous leukemia.