RUNX1 mutations enhance self-renewal and block granulocytic differentiation in human in vitro models and primary AMLs
RUNX1 mutations enhance self-renewal and block granulocytic differentiation in human in vitro models and primary AMLs
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DOI：
10.1182/bloodadvances.2018024422
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发表时间：
2019-02-12
期刊：
影响因子：
7.5
通讯作者：
Vellenga, Edo
中科院分区：
文献类型：
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作者：
Gerritsen, Mylone;Yi, Guoqiang;Vellenga, Edo
为了揭示RUNX1相关转录因子1 （RUNX1）突变促进白血病转化的分子机制，我们在人CD34（+）干细胞/祖细胞和人诱导多能干细胞（iPSCs）中引入了RUNX1- s291fs300x突变。在这两种模型中，RUNX1mut过表达强烈损害髓细胞承诺。相反，自我更新增强，如所示，通过增加长期培养启动细胞频率和增强集落形成细胞复制能力。runx1mut转导的脐带血（CB） CD341细胞的长期悬浮培养持续超过100天，在此期间，细胞表现出未成熟的粒细胞-巨噬细胞祖细胞样CD341/CD1231/CD45RA1表型。CD341/CD382造血干细胞（HSC）群体最有可能作为细胞起源，因为HSC在RUNX1mut过表达时提供了最佳的长期增殖潜力。在RUNX1mut细胞中CEBPA表达降低，CEBPA的重新表达部分恢复了分化。对CB/iPSC系统和主要患者样本的RNA-seq分析证实，RUNX1突变诱导髓细胞分化阻断，并且一组常见的runx1mut上调靶基因在与核小体组装和染色质结构相关的基因本体术语中被强烈富集。有趣的是，与AML1-ETO在急性髓性白血病（AMLs）中的结合相比，我们发现RUNX1mut的基因组分布和基因如TCF4、MEIS1和HMGA2的差异表达显著不同，这可能是RUNX1mut和AML1-ETO患者临床结果差异的潜在原因。总之，RUNX1mut似乎诱导了一个特定的转录程序，有助于白血病转化。
To unravel molecular mechanisms by which Runt-related transcription factor 1 (RUNX1) mutations contribute to leukemic transformation, we introduced the RUNX1-S291fs300X mutation in human CD34(+) stem/progenitor cells and in human induced pluripotent stem cells (iPSCs). In both models, RUNX1mut overexpression strongly impaired myeloid commitment. Instead, self-renewal was enhanced, as shown, by increased long-term culture-initiating cell frequencies and enhanced colony-forming cell replating capacity. Long-term suspension cultures with RUNX1mut-transduced cord blood (CB) CD341 cells continued for more than 100 days, during which the cells displayed an immature granulocyte-macrophage progenitor-like CD341/CD1231/CD45RA1 phenotype. The CD341/CD382 hematopoietic stem cell (HSC) population most likely acted as cell of origin, as HSCs provided the best long-term proliferative potential on overexpression of RUNX1mut. CEBPA expression was reduced in RUNX1mut cells, and reexpression of CEBPA partly restored differentiation. RNA-seq analysis on CB/iPSC systems and on primary patient samples confirmed that RUNX1 mutations induce a myeloid differentiation block, and that a common set of RUNX1mut-upregulated target genes was strongly enriched for gene ontology terms associated with nucleosome assembly and chromatin structure. Interestingly, in comparison with AML1-ETO binding in acute myeloid leukemias (AMLs), we found significantly distinct genomic distribution and differential expression for RUNX1mut of genes such as TCF4, MEIS1, and HMGA2 that may potentially contribute to the underlying difference in clinical outcomes between RUNX1mut and AML1-ETO patients. In conclusion, RUNX1mut appears to induce a specific transcriptional program that contributes to leukemic transformation.