干扰HMGA2基因表达抑制HL60细胞的增殖及浸润

Interference of HMGA2 expression inhibits the proliferation and invasion of HL-60 cells

目的:探索干扰高迁移率族蛋白A2(high mobility group protein A2,HMGA2)基因的表达对HL-60白血病细胞体外增殖、浸润的影响。方法:实验分为3组,实验组为稳定转染慢病毒干扰HMGA2基因表达载体的HL-60细胞;阴性对照组为稳定转染慢病毒空载体HL-60细胞;空白对照组为未转染的HL60细胞。3组分别接种BALB/c裸鼠建立种植瘤模型,检测接种后各个时间点裸鼠外周血和骨髓中白血病细胞的比例(肿瘤负荷)、生活质量,计算接种40 d后各组小鼠的肝脾指数。结果:RTPCR及Western印迹证明干扰RNA慢病毒表达载体可明显降低HL-60细胞靶基因的表达。接种后骨髓涂片结果显示裸鼠白血病模型成功建立。接种后21,28,40 d,实验组HL-60细胞在小鼠外周血和骨髓中的比例均明显低于阴性对照组及空白对照组,差异有统计学意义(P<0.05),其白血病细胞比例随接种时间延长而增加的速度亦明显变缓;且实验组小鼠萎糜少动、腹部膨隆、皮下结节等并发症出现时间明显较空白对照组及阴性对照组延迟;接种40 d后实验组小鼠肝脾指数分别为66.76±5.56和20.57±0.75,均明显低于其余两组,差异有统计学意义(P<0.05)。结论:干扰HMGA2基因表达,可明显抑制HL60白血病细胞在小鼠体内增殖、浸润。

Objective： To investigate the effect of interference of high-mobility-group protein A2（HMGA2） on the in-vitro proliferation and invasion of HL-60 cells. Methods： RNA interference was used to inhibit HMGA2 expression by HL-60 cells. Animal model was established by inoculating nude mice with HL-60 cells, which was stably transfected with HMGA2-specific shRNA expression vector, and cells transfected with blank vector were used as negative control and cells without transfection as blank control. At different time points after inoculation, the percentage of leukemic cells in peripheral blood（PB） and bone marrow（BM） was detected by Wright＇s staining and spleen and liver index were calculated at day 40 after inoculation. Results： RT-PCR and Western blot showed that HMGA2 expression by HL-60 cells was markedly reduced. BM smear demonstrated that HL-60 cells transfected with or without vectors were successfully implanted into nude mice. At day 21, 28, 40 after inoculation, significantly lower percentage of leukemic cells in PB and BM was seen in mice inoculated with HMGA2-targeted HL-60 cells than that in mice from both negative and blank control（P〈0.05）. The increase of leukemic cells in PB and BM along with prolonged time after inoculation was markedly slowed in HMGA2-targeted mice as compared with the other two groups. The complications occurred of mice in the experimental group, such as moving slowing, the abdominal swelling and the subcutaneous nodules were significantly delayed. The liver and spleen index determined in HMGA2-targeted mice were respectively 66.76±5.56 and 20.57±0.75, both which were remarkably lower than that in mice from the other groups（P〈0.05）. Conclusion： Interference of HMGA2 expression could remarkably inhibited HL-60 cell proliferation and invasion in nude mice.