ANGPTL 2 promotes tumor metastasis in hepatocellular carcinoma

Background and Aim Angiopoietin‐like protein 2 ( ANGPTL 2) plays various roles in metabolism, vascular biology, inflammation, and tumor metastasis, but little is known about its function in human hepatocellular carcinoma ( HCC ) metastasis. This study aimed to further explore the function of ANGPTL 2 on migration and invasion of liver cancer cells. Methods Quantitative real‐time polymerase chain reaction, Western blotting, immunohistochemistry, transwell migration, and invasion assays were performed to clarify the function of ANGPTL 2 in the regulation of cell migration and invasion in human HCC . Results In HCC patients, ANGPTL 2 expression was higher in HCC tissues compared with matched noncancerous liver tissues. And the ANGPTL 2 levels of HCC tissues positively correlated with intrahepatic metastasis in HCC patients. Overexpression of ANGPTL 2 significantly increased migration and invasion of HCC cells in vitro , and promoted intrahepatic and distal pulmonary metastasis in vivo , while knockdown of endogenous ANGPTL 2 resulted in a reduced migration and invasion in vitro . Colony formation assay and 3‐(4,5‐Dimethylthiazol‐2‐yl)‐2, 5‐diphenyltetrazolium bromide ( MTT ) assay showed ANGPTL 2 did not affect cell proliferation in vitro , whereas overexpression of ANGPTL 2 promoted tumor formation in xenograft animal model. Conclusions Our findings show that ANGPTL 2 drives human HCC metastasis and provides a potential therapeutic target for HCC treatment.