Gene expression profiling of LT-HSCs and ST-HSCs conditionally expressing MLL-ENL

We have developed a new conditional transgenic mouse showing that MLL-ENL, at an endogenous-like expression level, induces leukemic transformation selectively in LT-HSCs. To investigate the molecular mechanism of leukemic transformation in LT-HSCs conditionally expressing MLL-ENL, we preliminarily performed comprehensive gene expression profiling of CreER-transduced LT-HSCs and ST-HSCs using cDNA microarray analysis. For initial screening of candidate genes invloved in the leukemic transformation, total RNA was extracted from colony-forming cells derived from LT-HSCs and ST-HSCs transduced with CreER or mock. Four samples were analyzed, and CreER-transduced LT/ST-HSC-derived cells were compared with mock-transduced LT/ST-HSC-derived cells, while CreER/mock-transduced LT-HSC-derived cells were compared with CreER/mock-transduced ST-HSC-derived cells.

我们开发了一株新型条件性转基因小鼠，该模型显示，以近似内源性的表达水平表达混合谱系白血病-ENL融合基因（MLL-ENL），可在长期造血干细胞（LT-HSCs）中选择性诱导白血病转化。为探究条件性表达MLL-ENL的LT-HSCs中白血病转化的分子机制，我们初步采用cDNA芯片分析（cDNA microarray analysis），对他莫昔芬诱导型Cre重组酶（CreER）转导的LT-HSCs与短期造血干细胞（ST-HSCs）开展了全基因组基因表达谱分析。为初步筛选参与白血病转化的候选基因，我们从经CreER转染或mock转染的LT-HSCs与ST-HSCs所来源的集落形成细胞中提取了总RNA。本研究共分析4份样本：将CreER转导的LT/ST-HSC来源细胞与mock转染的LT/ST-HSC来源细胞进行对比，同时将CreER/mock转导的LT-HSC来源细胞与CreER/mock转导的ST-HSC来源细胞进行对比。