MicroRNA-144 dysregulates the transforming growth factor-β signaling cascade and contributes to the development of bronchiolitis obliterans syndrome after human lung transplantation

J Heart Lung Transplant. 2015 Sep;34(9):1154-62. doi: 10.1016/j.healun.2015.03.021. Epub 2015 Mar 27.


Background: Bronchiolitis obliterans syndrome (BOS), chronic lung allograft rejection, remains an impediment for the function of the transplanted organ. In this study, we defined the role of the microRNA (miRNA) miR-144 in fibroproliferation leading to BOS.

Methods: Biopsy specimens were obtained from 20 lung transplant recipients with BOS((+)) and 19 without BOS((-)). Expression of miR-144 and its target, transforming growth factor-β (TGF-β)-induced factor homeobox 1(TGIF1), were analyzed by real-time polymerase chain reaction and Western blot. Overexpression of miR-144 and luciferase reporter genes were performed to elucidate miRNA-target interactions. The function of miR-144 was evaluated by transfecting fibroblasts and determining the response to TGF-β by analyzing Sma- and Mad-related family (Smads), fibroblast growth factor, TGF-β, and vascular endothelial growth factor. Smooth muscle actin-α-positive stress fibers and F-actin filaments in lung fibroblasts were analyzed by immunofluorescence.

Results: Analysis of miR-144 in the biopsy specimens demonstrated 4.1 ± 0.8-fold increases in BOS(+) compared with BOS(-) patients, with a significant reduction in TGIF1 (3.6 ± 1.2-fold), a corepressor of Smads. In vitro transfection confirmed that over-expression of miR-144 results in a reduction in TGIF1 and an increase in SMAD2, SMAD4, fibroblast growth factor-6, TGF-β, and vascular endothelial growth factor. Increasing miR-144 by transfecting, increased smooth muscle actin-α and fibronectin, and knockdown of miR-144 diminished fibrogenesis in MRC-5 fibroblasts.

Conclusions: miR-144 is a critical regulator of the TGF-β signaling cascade and is over-expressed in lungs with BOS. Therefore, miR-144 is a potential target toward preventing fibrosis leading to BOS after lung transplant.

Keywords: TGF-β.; bronchiolitis obliterans syndrome; lung transplantation; microRNA.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Blotting, Western
  • Bronchiolitis Obliterans / prevention & control*
  • Female
  • Fibroblast Growth Factors / analysis
  • Fibroblasts / chemistry
  • Fibrosis / prevention & control
  • Fluorescent Antibody Technique
  • Homeodomain Proteins / analysis
  • Humans
  • Lung / chemistry
  • Lung Transplantation*
  • Male
  • MicroRNAs / physiology*
  • Middle Aged
  • Muscles / chemistry
  • Real-Time Polymerase Chain Reaction
  • Repressor Proteins / analysis
  • Smad Proteins / analysis
  • Smad2 Protein / analysis
  • Smad4 Protein / analysis
  • Transfection
  • Transforming Growth Factor beta / analysis
  • Transforming Growth Factor beta / physiology*
  • Vascular Endothelial Growth Factor A / analysis


  • Homeodomain Proteins
  • MIRN144 microRNA, human
  • MicroRNAs
  • Repressor Proteins
  • Smad Proteins
  • Smad2 Protein
  • Smad4 Protein
  • TGIF1 protein, human
  • Transforming Growth Factor beta
  • Vascular Endothelial Growth Factor A
  • Fibroblast Growth Factors