Effects of isoviolanthin on TGF-β1-induced matrix metalloproteinase (MMP)-2 and -9 in HCC cells. (A) HepG2 and Bel-7402 cells were treated with 10 ng/mL TGF-β1 for 48 h, during which isoviolanthin (2.5 µM, 5 µM, and 10 µM) was added for the last 24 h. The secretion of MMP-2 and -9 in HCC cell supernatants was detected by ELISA; (B) The protein levels of MMP-2 and -9 in HCC cells were examined by Western blot analysis. GAPDH was used as a loading control. Representative images and bar graphs (mean ± SD) are shown, n = 3. ** p < 0.01 versus the control group; #
p < 0.05, ##
p < 0.01 versus the TGF-β1 group.