Twist-1基因在髓系白血病细胞中的表达及其作用

Expression and function of Twist-1 gene in myeloid leukemia cells

目的:检测Twist-1基因在白血病患者和造血系统恶性肿瘤细胞系中的表达情况,并探讨其高表达对髓系白血病细胞增殖和凋亡的影响。方法:用Real-time PCR检测急性髓系白血病(acute myeloid leukemia,AML)、急性淋巴细胞白血病(acute lymphoid leukemia,ALL)、慢性粒细胞白血病(chronic myeloid leukemia,CML)患者和正常人的骨髓单个核细胞对照以及造血系统恶性肿瘤细胞系中Twist-1 mRNA表达情况。构建Twist-1过表达及干扰载体,制备慢病毒并感染髓系白血病细胞系K562、U937、KG-1a,通过细胞计数实验、集落形成实验、流式细胞术、Annexin V/PI方法评价Twist-1对白血病细胞增殖、集落形成能力、周期、凋亡的影响。结果:Twist-1在AML及CML患者中的表达水平显著高于对照(均P<0.05),而ALL患者与对照组没有显著差异(P>0.05)。在K562、U937、KG-1a中过表达及干扰实验证实,Twist-1高表达促进肿瘤细胞增殖、集落形成并抑制细胞凋亡;干扰Twist-1表达则效果相反。结论:Twist-1高表达于AML、CML髓系白血病细胞,并促进白血病细胞的增殖和抑制凋亡。

Objective： To investigate the expression of Twist-1 gene in patients with leukemia and tumor cell lines of hematopoietic system and to discuss the effect of its overexpression on proliferation and apoptosis of myeloid leukemic cells. Methods： Expressions of Twist-1 mRNA of hematopoietic tumor cell lines and PBMCs in patients with acute myeloid leukemia（ AML）,acute lymphoid leukemia（ ALL） or chronic myeloid leukemia（ CML） as well as in normal healthy human were detected by Real-time PCR. Lentiviral vector for overexperession of Twist-1（ p CDH1-Twist-1） were constructed and transduced into myeloid leukemic K562,U937 and KG-1a cell lines. Effect of Twist-1 on proliferation,colony forming,cell cycle and apoptosis of the leukemic cells was evaluated by cell counting,colony forming,flow cytometry and Annexin V / PI assays. Results： Expressions of Twist-1in patients with AML and CML were significantly higher than that in control group（ all P〈0. 05）,but there was no significant difference between all patients group and control group（ P〈0. 05）. The overexpression and interference analyses demonstrated that overexpression of Twist-1 in myeloid leukemic K562,U937 and KG-1a cell lines promoted proliferation and colony formation of the tumor cells,and inhibited apoptosis of the cells. Howevere,interfering expression of Twist-1 had the opposite effect. Conclusion： Twist-1 was overexpressed in myeloid leukemic K562,U937 and KG-1a cell lines and its overexpression could promote proliferation of the leukemia cells and inhibit their apoptosis.