HSPG2 and hepatocellular carcinoma: Analysis of the efficacies of sorafenib and regorafenib in HCC cells using proliferation assays in epithelial PLC/PRF/5 and mesenchymal SNU-457 revealed similar EC50 values for sorafenib and regorafenib, with higher EC50 values SNU-475 compared to PLC/PRF/5 cells for both kinase inhibitors (Fig. 6A,B).