Tumour-secreted miR-9 promotes endothelial cell migration and angiogenesis by activating the JAK-STAT pathway

EMBO J. 2012 Aug 29;31(17):3513-23. doi: 10.1038/emboj.2012.183. Epub 2012 Jul 6.

Abstract

Angiogenesis plays a crucial role during tumorigenesis and much progress has been recently made in elucidating the role of VEGF and other growth factors in the regulation of angiogenesis. Recently, microRNAs (miRNAs) have been shown to modulate a variety of physiogical and pathological processes. We identified a set of differentially expressed miRNAs in microvascular endothelial cells co-cultured with tumour cells. Unexpectedly, most miRNAs were derived from tumour cells, packaged into microvesicles (MVs), and then directly delivered to endothelial cells. Among these miRNAs, we focused on miR-9 due to the strong morphological changes induced in cultured endothelial cells. We found that exogenous miR-9 effectively reduced SOCS5 levels, leading to activated JAK-STAT pathway. This signalling cascade promoted endothelial cell migration and tumour angiogenesis. Remarkably, administration of anti-miR-9 or JAK inhibitors suppressed MV-induced cell migration in vitro and decreased tumour burden in vivo. Collectively, these observations suggest that tumour-secreted miRNAs participate in intercellular communication and function as a novel pro-angiogenic mechanism.

MeSH terms

  • Animals
  • COS Cells
  • Cell Line
  • Cell Line, Tumor
  • Cell Movement
  • Chlorocebus aethiops
  • Endothelial Cells / physiology*
  • Humans
  • Janus Kinase 1 / antagonists & inhibitors
  • Janus Kinase 1 / metabolism
  • Janus Kinase 2 / antagonists & inhibitors
  • Janus Kinase 2 / metabolism
  • Mice
  • Mice, Inbred BALB C
  • MicroRNAs / biosynthesis*
  • Neoplasms / drug therapy
  • Neoplasms / genetics*
  • Neoplasms / pathology
  • Neovascularization, Pathologic / drug therapy
  • Neovascularization, Pathologic / genetics*
  • Neovascularization, Pathologic / pathology
  • Protein Kinase Inhibitors / therapeutic use
  • STAT1 Transcription Factor / antagonists & inhibitors
  • STAT1 Transcription Factor / metabolism
  • STAT3 Transcription Factor / antagonists & inhibitors
  • STAT3 Transcription Factor / metabolism
  • Signal Transduction
  • Suppressor of Cytokine Signaling Proteins / metabolism
  • Up-Regulation
  • Xenograft Model Antitumor Assays

Substances

  • MicroRNAs
  • Protein Kinase Inhibitors
  • SOCS5 protein, human
  • STAT1 Transcription Factor
  • STAT1 protein, human
  • STAT3 Transcription Factor
  • STAT3 protein, human
  • Suppressor of Cytokine Signaling Proteins
  • JAK1 protein, human
  • JAK2 protein, human
  • Janus Kinase 1
  • Janus Kinase 2