TM4SF5 and hepatocellular carcinoma: TM4SF5 is highly expressed in diverse cancers, including liver, colon, pancreatic, and esophageal cancers.6., 7., 8. Previously, we reported that TM4SF5 plays a critical role in HCC development and metastasis; specifically, it mediates the epithelial-mesenchymal transition (EMT) and proliferation by phosphorylating FAK/c-Src and p27Kip1 and upregulating the expression of p27Kip1, and angiogenesis by upregulating the expression of vascular endothelial growth factor (VEGF).7