Figure 2. Downregulation expression of fibronectin by transfection with pSup-Smad7 siRNA. Fibronectin is a glycoprotein of the extracellular matrix that binds to membrane-spanning receptor proteins called integrins. There is significance among expression of fibronectin protein in the HTM transfected with Smad7siRNA, TGF-β2 group, control group, and TGF-β2 plus vehicle group (p<0.01). Downregulation of fibronectin was detected in HTM transfected with pSup-Smad7 siRNA.