Organ microenvironment affects growth and metastasis of hepatocellular carcinoma via the TGF-β/Smad pathway in mice

The interaction between cancer and the organ microenvironment is complex, and the transforming growth factor-β (TGF-β)/Smad pathway plays an important role in this interaction. However, the role of the organ microenvironment in hepatocellular carcinoma (HCC) is not well understood. To evaluate the effect of the organ microenvironment and the role of the TGF-β/Smad pathway, MHCC97-H cells were inoculated subcutaneously into nude mice and the resulting MHCC97-H subcutaneous tumor tissues were implanted into the livers of the mice. We found a higher tumor weight and less pulmonary metastasis for the cancers in liver sites than for those in subcutaneous sites; the TGF-β1 levels were significantly different between the tumor models and correlated with tumor metastasis. Our results suggest that the organ microenvironment affects the growth and invasion of liver cancer cells. The TGF-β/Smad pathway is significant in the interaction between HCC and its microenvironment and affects the progression of HCC.