PECAM1 and hepatocellular carcinoma: The mechanism of HCC-induced endothelial cell migration was generally considered to be related to various cytokines of HCC cells such as vascular endothelial growth factor (VEGF) family, fibroblast growth factors (FGF) family, Angiopoietin2, Angiotropin, tumor necrosis factor (TNF)-α, colony stimulating factors (CSFs), CXC chemokines with ELR motif, hepatocyte growth factor (HGF), platelet endothelial cell adhesion molecule- (PECAM-) 1, and Integrins [24].