Dakir El-Habib, Mollinedo Faustino
Instituto de Biología Molecular y Celular del Cáncer, Centro de Investigación del Cáncer, Consejo Superior de Investigaciones Científicas (CSIC)-Universidad de Salamanca, Salamanca, Spain.
Faculty of Biology, University of Latvia, Riga, Latvia.
Oncotarget. 2019 Sep 3;10(51):5313-5331. doi: 10.18632/oncotarget.27123.
MicroRNAs (miRNAs, miRs) are short non-coding post-transcriptional regulators of gene expression in normal physiology and disease. Acute myeloid leukemia is characterized by accumulation of malignantly transformed immature myeloid precursors, and differentiation therapy, used to overcome this differentiation blockage, has become a successful therapeutic option. The human HL-60 acute leukemia cell line serves as a cell culture model for granulocytic maturation, and dimethyl sulfoxide (DMSO) incubation leads to its differentiation towards neutrophil-like cells, as assessed by biochemical, functional and morphological parameters. DMSO-induced HL-60 cell differentiation constitutes an excellent model to examine molecular processes that turn a proliferating immortal leukemic cell line into mature non-proliferating and apoptosis-prone neutrophil-like end cells. By performing genome-wide miRNA profiling and functional assays, we have identified a signature of 86 differentially expressed canonical miRNAs (51 upregulated; 35 downregulated) during DMSO-induced granulocytic differentiation of HL-60 cells. Quantitative real-time PCR was used to validate miRNA expression. Among these differentially expressed canonical miRNAs, we found miR-125a-5p upregulation and miR-17-92 cluster downregulation acted as major regulators of granulocytic differentiation in HL-60 cells. Enforced expression of miR-125a-5p promoted granulocytic differentiation in HL-60 cells, whereas miR-17-92 ectopic expression inhibited DMSO-induced HL-60 granulocytic differentiation. Ectopic expression of miR-125a-5p also promoted granulocytic differentiation in human acute promyelocytic leukemia NB4 cells, as well as in naïve human primary CD34-hematopoietic progenitor/stem cells. These findings provide novel molecular insights into the identification of miRNAs regulating granulocytic differentiation of human leukemia cells and normal CD34-hematopoietic progenitor/stem cells, and may assist in the development of novel miRNA-targeted therapies for leukemia.
微小RNA（miRNA，miR）是正常生理和疾病中基因表达的短链非编码转录后调节因子。急性髓系白血病的特征是恶性转化的未成熟髓系前体细胞的积累，用于克服这种分化阻滞的分化疗法已成为一种成功的治疗选择。人HL-60急性白血病细胞系作为粒细胞成熟的细胞培养模型，通过生化、功能和形态学参数评估，二甲基亚砜（DMSO）孵育可使其向中性粒细胞样细胞分化。DMSO诱导的HL-60细胞分化构成了一个优秀的模型，用于研究将增殖性永生白血病细胞系转变为成熟的非增殖性且易于凋亡的中性粒细胞样终末细胞的分子过程。通过进行全基因组miRNA谱分析和功能测定，我们在DMSO诱导的HL-60细胞粒细胞分化过程中鉴定出86个差异表达的经典miRNA的特征（51个上调；35个下调）。使用定量实时PCR验证miRNA表达。在这些差异表达的经典miRNA中，我们发现miR-125a-5p上调和miR-17-92簇下调是HL-60细胞粒细胞分化的主要调节因子。miR-125a-5p的强制表达促进了HL-60细胞的粒细胞分化，而miR-17-92的异位表达抑制了DMSO诱导的HL-60粒细胞分化。miR-125a-5p的异位表达还促进了人急性早幼粒细胞白血病NB4细胞以及未成熟的人原代CD34造血祖细胞/干细胞的粒细胞分化。这些发现为鉴定调节人白血病细胞和正常CD34造血祖细胞/干细胞粒细胞分化的miRNA提供了新的分子见解，并可能有助于开发针对白血病的新型miRNA靶向疗法。
