Reduced miR-126 expression facilitates angiogenesis of gastric cancer through its regulation on VEGF-A

Oncotarget. 2014 Dec 15;5(23):11873-85. doi: 10.18632/oncotarget.2662.

Abstract

miR-126 is an endothelial-specific microRNA essential for governing vascular integrity and angiogenesis. Its role in tumor angiogenesis of gastric cancer (GC) is unclear. This study aimed at determining the role of miR-126 in GC angiogenesis. Down-regulation of miR-126 was found to inversely correlate with an increased microvessel density (MVD) and vascular endothelial growth factor A (VEGF-A) expression in gastric cancer tissues. Bioinformatics analysis and luciferase reporter assay revealed that miR-126 directly targeted the 3'-untranslated region (3'-UTR) of VEGF-A mRNA. In addition, the restoration of miR-126 expression by lentivirus-miR-126 (Lenti-miR-126) transfection obviously reduced the expression of VEGF-A and the activition of its downstream genes, Akt, mTOR and Erk1/2 in gastric cancer cell lines SGC-7901, MKN-28 and MKN-45. In contrast, the down-regulation of miR-126 expression by lentivirus-anti-miR-126 (Lenti-anti-miR-126) transfection obviously up-regulated the expression of VEGF-A and its downstream signaling pathways. In vivo xenograft mice model experiments clarified the down-regulation of VEGF-A and MVD as well as inhibition of tumor growth by up-regulation of miR-126. Overall, the results from our study suggested that miR-126 could suppress tumor growth and tumor angiogenesis of GC through VEGF-A signaling, and it is a novel potential therapeutic target for GC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / genetics
  • Adenocarcinoma / metabolism
  • Adenocarcinoma / pathology*
  • Animals
  • Blotting, Western
  • Cell Line, Tumor
  • Down-Regulation
  • Female
  • Gene Expression Regulation, Neoplastic / genetics*
  • Heterografts
  • Humans
  • Immunohistochemistry
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • MicroRNAs / biosynthesis*
  • MicroRNAs / genetics
  • Neovascularization, Pathologic / genetics*
  • Real-Time Polymerase Chain Reaction
  • Reverse Transcriptase Polymerase Chain Reaction
  • Stomach Neoplasms / blood supply
  • Stomach Neoplasms / genetics
  • Stomach Neoplasms / metabolism
  • Stomach Neoplasms / pathology*
  • Transfection
  • Vascular Endothelial Growth Factor A / biosynthesis*

Substances

  • MIRN126 microRNA, human
  • MicroRNAs
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A