We found that the protein level of MMP9 was unchanged, while TRIM9 overexpression facilitated MMP2 production in Biu-87/T24 cells, and blockade of Smad2/3 signaling suppressed MMP2 expression (Fig. 3G), indicating that Smad2/3 mediated downstream MMP2 production in bladder cancer cells. This evidence concerns the gene MMP9 and urinary bladder cancer.