Differential accessibility landscapes in MLL-AF9-driven leukemia stem cells upon inhibiiton of purine metabolism. Differential accessibility landscapes in MLL-AF9-driven leukemia stem cells upon inhibiiton of purine metabolism

Targeted metabolomics analysis of bulk leukemia cells and leukemia stem cells (LSCs) derived from the MLL-AF9-driven acute myeloid leukemia (AML) model, and normal granulocyte-monocyte progenitor (GMP) cells and whole bone marrow (WBM) cells from healthy mice, revealed an enhanced purine metabolism in AML LSCs. Inhibiting the purine biosynthetic pathway using mycophenolate mofetil (MMF) promoted myeloid differentiation and induced alterations in the chromatin accessibility landscape. These findings underscore the pivotal role of purine metabolism in regulating LSC activity. Overall design: To investigate the alterations of chromatin accessibility landscape in MLL-AF9-driven leukemia stem cells (LSCs), control or MMF-treated LSCs were subjected to tagmentation using Tn5. The assay for transposase-accessible chromatin with sequencing (ATAC-Seq) was performed and the obtained sequencing data were analyzed to identify and characterize changes in the chromatin accessibility landscape. Comparative analysis was conducted between MMF-treated and untreated MLL-AF9-driven LSCs to identify differential chromatin accessibility patterns.

本研究针对MLL-AF9驱动的急性髓系白血病（AML）模型来源的总体白血病细胞与白血病干细胞（LSCs），以及健康小鼠的正常粒单核细胞祖细胞（GMP）与全骨髓（WBM）细胞开展靶向代谢组学分析，结果显示AML LSCs中嘌呤代谢显著增强。采用霉酚酸酯（MMF）抑制嘌呤生物合成通路，可促进髓系分化并诱导染色质可及性图谱发生改变。上述研究结果凸显了嘌呤代谢在调控LSC活性中的关键作用。
整体实验设计：为探究MLL-AF9驱动的白血病干细胞（LSCs）的染色质可及性图谱变化，分别对未经处理与经MMF处理的LSCs使用Tn5转座酶进行转座标签化反应，随后开展转座酶可及性染色质测序（ATAC-Seq），对所得测序数据进行分析以鉴定并表征染色质可及性图谱的变化。同时对经MMF处理与未处理的MLL-AF9驱动LSCs进行比较分析，以鉴定差异染色质可及性模式。