Modulation of FoxO1 expression by miR-21 to promote growth of pancreatic ductal adenocarcinoma

Cell Physiol Biochem. 2015;35(1):184-90. doi: 10.1159/000369686. Epub 2015 Jan 2.

Abstract

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal primary tumors in humans, with undetermined tumorigenesis. Although previous work by us, and by others, has clearly demonstrated an involvement of miR-21 in the growth of PDAC, the underlying mechanism has not been clarified.

Methods: Here we analyzed the regulation of FoxO1 by miR-21 in vitro and in vivo, using luciferase-reporter assay and pancreatic intraductal infusion of antisense of miR-21, respectively.

Results: We found that overexpression of miR-21 in PDAC cells decreased FoxO1 protein levels, whereas inhibition of miR-21 increased FoxO1 levels. Further, miR-21 bound to FoxO1 mRNA to prevent its translation through its 3'UTR. Moreover, administration of antisense of miR-21 through an intraductal infusion system significantly decreased miR-21 levels and increased FoxO1 levels in implanted PDAC, resulting in a significant decrease in PDAC growth.

Conclusion: Taken together, our data highlight miR-21/FoxO1 axis as a novel therapeutic target for inhibiting the growth of PDAC.

MeSH terms

  • 3' Untranslated Regions
  • Animals
  • Base Sequence
  • Carcinoma, Pancreatic Ductal / diagnostic imaging*
  • Carcinoma, Pancreatic Ductal / metabolism
  • Carcinoma, Pancreatic Ductal / pathology
  • Cell Line, Tumor
  • Cell Proliferation
  • Forkhead Box Protein O1
  • Forkhead Transcription Factors / chemistry
  • Forkhead Transcription Factors / genetics
  • Forkhead Transcription Factors / metabolism*
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Mice
  • Mice, Inbred NOD
  • Mice, SCID
  • MicroRNAs / antagonists & inhibitors
  • MicroRNAs / metabolism*
  • Oligonucleotides, Antisense / metabolism
  • Pancreatic Neoplasms / diagnostic imaging*
  • Pancreatic Neoplasms / metabolism
  • Pancreatic Neoplasms / pathology
  • Radiography
  • Sequence Alignment
  • Transfection
  • Transplantation, Heterologous

Substances

  • 3' Untranslated Regions
  • FOXO1 protein, human
  • Forkhead Box Protein O1
  • Forkhead Transcription Factors
  • MIRN21 microRNA, human
  • MicroRNAs
  • Oligonucleotides, Antisense