SMAD3 and hepatocellular carcinoma: In an HBx transgenic mouse model undergoing partial hepatectomy, TGF-β, Smad2, and phosphorylated Smad3/4 (ser423/425) were significantly overexpressed in the HBx transgenic mice liver compared to non-transgenic mice, indicating the impact of HBx on the TGF-β/Smad pathway, which promotes the progression of HCC (213).