全反式维甲酸诱导NB4和HL-60细胞分化过程中髓系分化相关的转录因子表达变化

Expression Pattern of Myeloid Differentiation-Related Transcription Factor mRNA in Differentiation of NB4 and HL-60 Cells Induced by All-trans Retinoic Acid

造血干细胞的自我更新、增殖、分化与成熟过程与转录因子调节密切相关。转录因子功能失调可能导致急性髓系白血病的发生。为研究急性髓系白血病细胞体外分化过程中转录因子表达变化,采用全反式维甲酸诱导NB4和HL-60细胞分化模型,瑞氏-姬姆沙染色观察细胞形态,流式细胞术检测细胞表面标志CD11b的表达,定量RT-PCR检测转录因子PU.1,C/EBPα,ε,γ,GATA1-,GATA2-mRNA的表达水平,用2-△△CT法对转录因子mRNA表达水平进行相对定量分析,并与对照组比较。结果表明:ATRA作用NB4细胞96小时,PU.1,C/EBPεmRNA表达水平显著上调,分别达到处理前的5.75倍和6.16倍;而C/EBPα,γ,GATA1-,GATA2-的mRNA表达水平均显著下调,仅为处理前的62%,31%,63%,8.7%,尤以GATA2-的表达水平下降最为显著。在HL-60细胞,ATRA作用96小时,PU.1,C/EBPα,ε的mRNA表达水平上调,分别为处理前1.97,1.95,2.35倍,而C/EBPγ,GATA1-,GATA2-的mRNA表达水平均显著下调,仅为处理前的20%,21%,18%。结论:转录因子异常表达在急性髓系白血病的发病中起重要作用。

Hematopoiesis is coordinated by a complex regulatory network of transcription factors that involves proliferation, differentiation and maturation of a very small population of pluripotent hematopoietic stem cells with self-renewing and differentiating into various specialized and distinct blood cell types. Malfunction of transcription factors may lead to diseases such as acute myeloid leukemia （AML）. The purpose of this study was to investigate the expression pattern of transcription factor mRNA in acute myeloid leukemia （AML） cells during in vitro differentiation. The 2 human leukemic cell lines HL-60 and N-B4 had been used as model cell lines. Differentiation of HL-60 and NB4 cells was induced by all-trans retinoic acid （ATRA） for 4 days. Morphological changes were observed by May-Gr unwald Giemsa stainings, the CD11b expression level was detected by flow cytometry. Transcription factor mRNA profiles （ PU. 1, C/EBPα,ε,γ, GATA-1, GATA-2 ） were determined by real time RT-PCR during in vitro HL-60 and NB4 differentiation; The expression level of transcription factor mRNA was relatively quantitatively analyzed by using 2-△△CT and compared with control group. The results showed that the expression levels of PU. 1 and C/EBP 8 mRNA in NB4 differentiation group were 5.75 and 6. 16, respectively, which were significantly higher than those in untreated group; while the expression level of C/EBPα,γ, GATA-1, GATA-2 mRNA in NB4 differentiation group were 62%, 31% ,63% and 8. 7% respectively, which were significantly lower than those in untreated group; In HL-60 differentiation group, the expression levels of PU. 1, C/EBPα,ε were 1.97,1.95 and 2.35 respectively, which were significantly higher than those in untreated group; while the expression levels of C/EBP3,, GATA-1, GATA-2 in HL-60 differentiation group were 20%, 21% and 18% respectively, which were significantly lower than those in untreated group. It is concluded that dysregulation of transcription factors is a key contributing factor in the pathogenesis of acute myeloid leukemia.