SMAD3 and urinary bladder cancer: FKA exhibited in vivo anti‐tumor activity in a bladder cancer xenograft model and in the UPII‐SV40T transgenic bladder cancer mouse model.32 A recent study showed that FKA significantly inhibited LPS‐induced activation of NF‐kB, AP‐1 and JNK/p38 MAPK signaling pathways.33 Notably, FKA is more effective than FKB in promoting Nrf2 activation, antioxidant genes (HO‐1 and γ‐GCLC) and GSH levels.24 Here, we hypothesized that FKA could alleviate TGF‐β1‐mediated ROS/Smad3 signaling, thereby preventing fibrotic pathology in vascular smooth muscle cells.