Oncogene-dependent control of miRNA biogenesis and metastatic progression in a model of undifferentiated pleomorphic sarcoma

J Pathol. 2013 Jan;229(1):132-40. doi: 10.1002/path.4099. Epub 2012 Nov 20.


Undifferentiated pleomorphic sarcoma (UPS) is one of the most common soft tissue malignancies. Patients with large, high-grade sarcomas often develop fatal lung metastases. Understanding the mechanisms underlying sarcoma metastasis is needed to improve treatment of these patients. Micro-RNAs (miRNAs) are a class of small RNAs that post-transcriptionally regulate gene expression. Global alterations in miRNAs are frequently observed in a number of disease states including cancer. The signalling pathways that regulate miRNA biogenesis are beginning to emerge. To test the relevance of specific oncogenic mutations in miRNA biogenesis in sarcoma, we used primary soft tissue sarcomas expressing either Braf(V600E) or Kras(G12D). We found that Braf(V600E) mutant tumours, which have increased MAPK signalling, have higher levels of mature miRNAs and enhanced miRNA processing. To investigate the relevance of oncogene-dependent alterations in miRNA biogenesis, we introduced conditional mutations in Dicer and showed that Dicer haploinsufficiency promotes the development of distant metastases in an oncogene-dependent manner. These results demonstrate that a specific oncogenic mutation can cooperate with mutation in Dicer to promote tumour progression in vivo.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Differentiation*
  • DEAD-box RNA Helicases / genetics
  • DEAD-box RNA Helicases / metabolism
  • Disease Progression
  • Gene Expression Regulation, Neoplastic
  • Haploinsufficiency
  • MAP Kinase Signaling System
  • Mice
  • MicroRNAs / biosynthesis*
  • Mutation
  • Neoplasm Invasiveness
  • Proto-Oncogene Proteins B-raf / genetics*
  • Proto-Oncogene Proteins p21(ras) / genetics*
  • Ribonuclease III / genetics
  • Ribonuclease III / metabolism
  • Sarcoma / genetics*
  • Sarcoma / metabolism
  • Sarcoma / secondary
  • Soft Tissue Neoplasms / genetics*
  • Soft Tissue Neoplasms / metabolism
  • Soft Tissue Neoplasms / pathology
  • Time Factors


  • MicroRNAs
  • Braf protein, mouse
  • Proto-Oncogene Proteins B-raf
  • Dicer1 protein, mouse
  • Ribonuclease III
  • DEAD-box RNA Helicases
  • Hras protein, mouse
  • Proto-Oncogene Proteins p21(ras)