摘要
本研究旨在检测独立生长因子(Gfi-1)在白血病患者的表达水平并探讨慢病毒介导的gfi-1基因沉默对人白血病细胞株K562增殖的影响。采用荧光实时定量PCR及Westernblot方法检测初治白血病患者gfi-1的表达水平,分析其在各型白血病中的表达情况。设计、合成一对针对gfi-1 mRNA的shRNA序列,退火后连接到pLVTHM干扰载体上,与psPAX2、PDM2G共转HEK293T细胞,包装产生慢病毒颗粒并测定病毒滴度,感染K562细胞,建立稳定株。应用实时定量PCR和Western blot方法检测K562细胞gfi-1及baxmRNA和蛋白的表达,并与对照组进行比较.结果表明:慢病毒介导的shgfi-1能明显降低gfi-1的mRNA及蛋白水平,而bax的mRNA及蛋白水平则都上调。CCK-8检测发现,与对照组相比,shgfi-1能明显抑制K562细胞的增殖。结论:gfi-1在初治白血病患者中的高表达可能参与白血病的发生发展。gfi-1特异的shRNA干扰可以有效地下调K562细胞gfi-1基因的表达,抑制K562细胞的增殖,gfi-1基因可能是白血病基因治疗的一个有效靶点。
This study was aimed to quantitatively detect the expression levels of gfi-1 gene in leukemia patients, and to investigate the effect of gfi-1 gene silenced by short hairpin RNA （shRNA） on proliferation of leukemia cell line K562. Quantitative real-time PCR and Western blot were used to detect the mRNA and protein expression levels of GFI- 1 in newly diagnosed patients with leukemia. One pair of oligonucleotide sequences targeted at human gfi-1 mRNA were designed and synthesized. The annealed oligonucleotide fragments were subcloned into pLVTHM vector. Virus particles were collected when the control and shRNA vectors had been co-transfected with the psPAX2 packaging plasmid and the envelope plasmid pMD2 G into HEK-293T cells using Lipofectamine 2000. The K562 cells were transfused with 1 x l06 recombinant lentivirus-transfusing units plus 6μg/ml of polybrene. Rea-time PCR and Western blot were used to detect the expressions of gfi-1 and bax mRNA after lentivirus transfusion. CCK-8 assays was used to evaluate the proliferation potential of cells. The results showed that the gfi-1 expression level in all leukemia patients was significantly higher than that in normal group（p 〈 0.05 ） ; the gfi-1 mRNA expression in chronic myeloid leukemia（CML） and acute myeloid leukemia（AML） or acute lymphoid leukemia （ALL） patients was significantly higher than that in normal group （p 〈 0. 05） ; but the difference of gfi-1 mRNA expression between AL and CML or ALL and AML was not significant. Notably, the gfi-1 mRNA expression level had a positive correlation with high white blood cell count of 〉 20.0 × 10^9/L （p 〈 0. 05 ）. As was expected, the mRNA and protein level of gfi-1 was reduced significantly in K562 cells after lentivirus transfusion, wheras the mRNA and protein level of bax was upregulated. And CCK-8 assay showed that gfi-1 gene silencing can inhibit K562 proliferation. It is concluded that gfi-1 expression is upregulated in leukemia patients and may contribute to leukemogenesis. The gfi-1 specific shRNA mediated by lentivirus can effectively down-regulate the expression of gfi-1 and inhibit the proliferation of K562 cells, which lay a basis for further research on gene therapy in leukemia.
出处
《中国实验血液学杂志》
CAS
CSCD
2010年第4期849-854,共6页
Journal of Experimental Hematology
