Treatment with the herbal formula Songyou Yin inhibits epithelial-mesenchymal transition in hepatocellular carcinoma through downregulation of TGF-β1 expression and inhibition of the SMAD2/3 signaling pathway

It was previously reported that treatment with the herbal formula Songyou Yin (SYY) may serve a role in attenuating epithelial-mesenchymal transition (EMT). In the present study, the effect of treatment with SYY on transforming growth factor-β1 (TGF-β1)-induced EMT was investigated and the potential underlying molecular mechanisms were evaluated. MHCC97H cells were pretreated with SYY for 4 weeks and subsequently named MHCC97HSYY cells. Simultaneously, MHCC97H cells were cultured for 4 weeks without SYY and used as a negative control. Western blot analysis and enzyme‑linked immunosorbent assays demonstrated that treatment with SYY inhibited EMT‑associated changes and TGF‑β1 expression in MHCC97H cells. MHCC97H and MHCC97HSYY cells were treated with 10 ng/ml TGF‑β1 to induce EMT. The results of the present study demonstrated that pretreatment with SYY markedly inhibited TGF‑β1‑induced morphological changes, and reversed the expression of the EMT markers E‑cadherin and N‑cadherin. In addition, expression levels of the TGF‑β1 downstream proteins, phosphorylated mothers against decapentaplegic homologs (p‑SMAD)2 and 3, were reduced. Transwell assays indicated that pretreatment with SYY inhibited TGF‑β1‑induced cancer cell invasion and migration. The results of the present study indicate that SYY inhibited EMT through attenuation of TGF‑β1 expression, and downregulation of p-SMAD2 and 3.