BSG and hepatocellular carcinoma: Consistent with the previous reports [24], we found that overexpression of CD147 increased intrahepatic metastasis, in sharp contrast, the enhancement of intrahepatic metastasis induced by CD147 overexpression was significantly compromised by CTSB silence as well as cathepsin B inhibition (Fig. 8g), indicating that cathepsin B is an important effector involved in CD147 enhanced HCC metastasis.