ABSTRACT
<p><b>OBJECTIVE</b>To investigate the abnormal expression of interferon-induced transmembrane protein 3 (IFITM3) in hepatocellular carcinoma (HCC) and the effect of IFITM3 knock-down on the biological behaviors of hepatocellular carcinoma HepG2 cells.</p><p><b>METHODS</b>Western blot analysis and immunohistochemical staining were used to determine the expression of IFITM3 protein in 60 HCC samples and paired adjacent tissues. A small interfering RNA fragments of IFITM3 (IFITM3 siRNA) was transiently transfected into HepG2 cells and expressions of IFITM3 at mRNA and protein levels were examined by qRT-PCR and Western blotting. The changes in the proliferation of the transfected cells were determined using cell counting kit 8 (CCK8) assay, and the cell invasion and migration were tested using Transwell assay and wound-healing assay.</p><p><b>RESULTS</b>Compared with the adjacent tissues, HCC tissues expressed significantly higher levels of IFITM3. In HepG2 cells, transfection with IFITM3 siRNA resulted in significant down-regulation of IFITM3 expression at both the protein and mRNA levels and obviously suppressed cell proliferation, invasion, and migration ability as compared with the cells transfected with scrambled siRNA and control cells (P<0.05).</p><p><b>CONCLUSIONS</b>IFITM3, which is overexpressed in HCC, plays a vital role in the proliferation and invasion of HCC cells and may serve as a potential target for gene therapy of HCC.</p>