Mutations in the miR-142 gene are not common in myeloproliferative neoplasms

Effect of lncRNA XIST on acute myeloid leukemia cells via miR-142-5p-PFKP axis

Acute myeloid leukemia (AML) is the common blood cancer in hematopoietic system-related diseases and has a poor prognosis. Studies have shown that long non-coding RNAs (lncRNAs) are closely related to the pathogenesis of a variety of diseases, including AML. However, the specific molecular mechanism remains unclear. Hence, the objective of this study was to investigate the effect and mechanism of lncRNA X inactive specific transcript (lncRNA XIST) on AML. To achieve our objective, some tests were performed. Quantitative real-time polymerase chain reaction (qRT-PCR) was utilized to detect the expression of lncRNA XIST, miR-142-5p and the platelet isoform of phosphofructokinase (PFKP). The targeting relationship between miR-142-5p and lncRNA XIST and PFKP was verified by Pearson correlation analysis, dual-luciferase reporter assay, and pull-down assay. Functional experiments were used to analyze the effect and mechanism of action of knocking down lncRNA XIST on THP-1 and U937 cells. Compared with bone marrow cells, lncRNA XIST and PFKP expression levels were up-regulated and miR-142-5p expression levels were down-regulated in AML. Further analysis revealed that lncRNA XIST targeted and bound to miR-142-5p, and PFKP was a target gene of miR-142-5p. Knockdown of lncRNA XIST significantly promoted miR-142-5p expression to down-regulate PFKP in THP-1 and U937 cells, while the cell proliferation, cell viability, and cell cycle arrest were inhibited and apoptosis was increased. Knockdown of miR-142-5p reversed the functional impact of lncRNA XIST knockdown on AML cells. In conclusion, down-regulation of lncRNA XIST can affect the progression of AML by regulating miR-142-5p.

CMC: Cancer miRNA Census - a list of cancer-related miRNA genes

A growing body of evidence indicates an important role of miRNAs in cancer; however, there is no definitive, convenient-to-use list of cancer-related miRNAs or miRNA genes that may serve as a reference for analyses of miRNAs in cancer. To this end, we created a list of 165 cancer-related miRNA genes called the Cancer miRNA Census (CMC). The list is based on a score, built on various types of functional and genetic evidence for the role of particular miRNAs in cancer, e.g. miRNA-cancer associations reported in databases, associations of miRNAs with cancer hallmarks, or signals of positive selection of genetic alterations in cancer. The presence of well-recognized cancer-related miRNA genes, such as MIR21, MIR155, MIR15A, MIR17 or MIRLET7s, at the top of the CMC ranking directly confirms the accuracy and robustness of the list. Additionally, to verify and indicate the reliability of CMC, we performed a validation of criteria used to build CMC, comparison of CMC with various cancer data (publications and databases), and enrichment analyses of biological pathways and processes such as Gene Ontology or DisGeNET. All validation steps showed a strong association of CMC with cancer/cancer-related processes confirming its usefulness as a reference list of miRNA genes associated with cancer.

miR-142: A Master Regulator in Hematological Malignancies and Therapeutic Opportunities

MicroRNAs (miRNAs) are a type of non-coding RNA whose dysregulation is frequently associated with the onset and progression of human cancers. miR-142, an ultra-conserved miRNA with both active -3p and -5p mature strands and wide-ranging physiological targets, has been the subject of countless studies over the years. Due to its preferential expression in hematopoietic cells, miR-142 has been found to be associated with numerous types of lymphomas and leukemias. This review elucidates the multifaceted role of miR-142 in human physiology, its influence on hematopoiesis and hematopoietic cells, and its intriguing involvement in exosome-mediated miR-142 transport. Moreover, we offer a comprehensive exploration of the genetic and molecular landscape of the miR-142 genomic locus, highlighting its mutations and dysregulation within hematological malignancies. Finally, we discuss potential avenues for harnessing the therapeutic potential of miR-142 in the context of hematological malignancies.

Acquired miR-142 deficit in leukemic stem cells suffices to drive chronic myeloid leukemia into blast crisis

The mechanisms underlying the transformation of chronic myeloid leukemia (CML) from chronic phase (CP) to blast crisis (BC) are not fully elucidated. Here, we show lower levels of miR-142 in CD34+CD38- blasts from BC CML patients than in those from CP CML patients, suggesting that miR-142 deficit is implicated in BC evolution. Thus, we create miR-142 knockout CML (i.e., miR-142-/-BCR-ABL) mice, which develop BC and die sooner than miR-142 wt CML (i.e., miR-142+/+BCR-ABL) mice, which instead remain in CP CML. Leukemic stem cells (LSCs) from miR-142-/-BCR-ABL mice recapitulate the BC phenotype in congenic recipients, supporting LSC transformation by miR-142 deficit. State-transition and mutual information analyses of "bulk" and single cell RNA-seq data, metabolomic profiling and functional metabolic assays identify enhanced fatty acid β-oxidation, oxidative phosphorylation and mitochondrial fusion in LSCs as key steps in miR-142-driven BC evolution. A synthetic CpG-miR-142 mimic oligodeoxynucleotide rescues the BC phenotype in miR-142-/-BCR-ABL mice and patient-derived xenografts.