CD7阳性急性髓系白血病骨髓干／祖细胞5个基因表达的研究

本研究探讨abca5、mdr-1、kdr、dapk和irf-1 5个基因在CD7^＋急性髓细胞性白血病干／祖细胞的表达。利用实时定量RT—PCR（RQ—PCR）方法检测了15例正常骨髓（NBM）和16例AML患者骨髓单个核细胞（MNC）中5个基因的表达。采用流式细胞仪（FCM）分选8例NBM和21例AML患者骨髓CD34^＋CD38^＋祖细胞和CD34^＋CD38-干细胞，利用微量细胞RQ—PCR方法检测分选细胞中5个基因的表达。结果表明：NBMMNC均表达这5个基因，其中irf-1与dapk表达水平最高，相对表达量分别为4．08和3．86；abca5和mdr-1表达水平较低，为0．49和0．84；kdr表达最低为0．02。在经分选的CD34^＋CD38^＋祖细胞中，dapk和irf-1表达明显减低（P〈0．05），kdr表达明显增加（P〈0．05），其余2个基因无明显变化。在CD34^＋CD38^＋Lin-干细胞中，5个基因的表达均高于CD34^＋CD38^＋祖细胞，普遍增加至近2倍，而kdr增加了3倍，其中kdr和irf-l表达的增加具有统计学差异（P〈0．05）。与NBM相比，AMLMNC中5个基因的表达水平均有不同程度减低，以abca5、mdr-1、kdr和dapk最为显著（P〈0．05）。与AMLMNC相比，AMLCD34^＋CD38^＋细胞中，irf-1和dapk表达明显减低（P〈0．05），其余3个基因表达增加，以kdr表达增加有统计学意义（P〈0．05）。AMLCD34^＋CD38^＋与CD34^＋CD38^-细胞比较，发现5个基因在CD34^＋CD38^＋细胞中的表达均增加，尤以kdr和irf-1的表达增加有意义（P〈0．05）。AMLCD34^＋CD38^＋CD7^＋细胞与CD34^＋CD38^-CD7-细胞中5个基因的表达均比CD34^＋CD38^＋细胞中的高，其中只有CD34^＋CD38^- CD7^＋细胞中KDR和CD34^＋CD38^-CD7^-细胞中KDR和irf-1的表达增加并具有统计学差异（P〈0．05）。结论：NBM中kdr主要表达在干／祖细胞中，而dapk和irf-1主要表达在较分化的细胞中。5个基因在干细胞阶段的表达均高于祖细胞阶段。AMLCD34^＋CD38^-CD7^＋细胞与CD34^＋CD38^＋CD7^-都具有干／祖细胞的基因表达特点。

Expression of 5 Genes in CD7 Positive Acute Myeloid Leukemia Stem/ Progenitor Cells from Bone Marrow

This study was aimed to investigate abca5, mdr-1, kdr, dapk and irf-1 expressions in leukemia stem/ progenitor cells （LSC） from CD7 positive acute myeloid leukemia, the expression of these 5 genes in mononuclear cells （MNC） from 15 normal bone marrow （NBM） and 16 AML patients bone marrow （AML BM） specimen were detected by real-time quantitative PCR （RQ-PCR）. CD34^＋CD38^＋ progenitor cells and CD34^＋CD38^- Lin - stem cells were sorted by flow cytometry （FCM） from the MNCs of 10 NBM and 21 AML BM specimen. These 5 gene expressions in the sorted cells were detected by small amount cell RQ-PCR. The results showed that these 5 genes above mentioned all expressed in NBM-MNC, in which the expression levels of irf-1 and dapk were highest with the relative expression levels 4.08 and 3.86, the expression levels of abca 5 and mdr-1 were in the middle with the relative expression 0.49 and 0.84 respectively, the kdr expression was lowest with the relative expression level 0.02. In CD34^＋CD38^＋ progenitor cells, the expression level of kdr increased dramatically （p 〈 0.05 ） while irf-1 and dapk dramatically decreased （p 〈 0.05 ）. There was no obvious change of expression in the rest 2 genes. 5 genes all increased nearly 2 times as much as that in CD 3 4^＋ In CD34^＋CD38^- stem cells the expression level of these CD 3 8^＋progenitor cells , but kdr increased 3 times as much, and the increase of kdr and irf-1 expressions was of statistical significance （p 〈 0.05 ） . Compared with the NBM, expression levels of 5 genes in AML-MNC decreased, and out of them abca 5, mdr-1, kdr and dapk were decreased most remarkably（p 〈 0.05 ）. Comparison between AML CD34^＋CD38^＋ cells and AML MNC showed that the expression level of irf-1 and dapk were decreased dramatically （ p 〈 0. 05 ） while the rest 3 genes increased their expression with statistical significance （p 〈 0.05 ）. The expression levels of these 5 genes were higher in CD34^＋CD38^- cells than those in CD34^＋CD38^＋ stem cells, and the increase of kdr and irf-1 expressions showed statistical difference （p 〈 0.05 ）. These 5 genes expression levels were all higher than those inCD34^＋CD38^＋ cells whether in AML CD34^＋CD38^- CD7^- cells orCD34^＋CD38^- CD7 - cells. The increase of kdr expression in CD34^＋CD38^- CD7^- cells as well as kdr and irf-1 expressions in CD34^＋CD38^- CD7 - cells were all of statistical significance （p 〈 0.05 ）. In conclusion the expression level of kdr in NBM was highest in stem cells while dapk and irf-1 were highest in differentiated ceils. The expression levels of these 5 genes in CD34^＋CD38^- Lin - stem cells were higher than those in CD34^＋CD38^＋ progenitor cells. The gene expressions in AML CD34^＋CD38^- CD7^＋ cells and CD34^＋CD38^- CD7 - cells are in accordance with the characteristics of stem cells.