目的：探讨干扰素诱导跨膜蛋白3（IFITM3）在原发性肝癌中的表达及作用。方法：用免疫组化与Western blot 检测60 例肝癌组织及对应癌旁组织中IFITM3 以及基质金属蛋白酶9（MMP-9）蛋白的表达；构建IFITM3 小干扰RNA 片段（psilencer3.1-shIFITM3）转染肝癌HepG2 细胞，用实时荧光定量PCR 及Western blot 法、CCK8 法、Transwell 试验和划痕试验分别检测细胞转染后IFITM3 和MMP-9 mRNA 及蛋白表达、增殖能力以及侵袭与迁移能力的变化。结果： 与癌旁组织比较，肝癌组织中IFITM3 与MMP-9 的蛋白的阳性表达率与表达量均明显升高（81.67% vs. 13.33%；88.33% vs. 8.33%， 均P<0.05）；psilencer3.1-shIFITM3 转染后，HepG2 细胞IFITM3 和MMP-9 的mRNA 与蛋白表达水平、细胞增值率均明显降低，穿膜细胞数明显减少，划痕融合速率明显减慢。以上定量指标间的差异均有统计学意义（均P<0.05）。结论：原发性肝癌中IFITM3 表达增高，高表达的IFITM3 可能通过调控MMP-9 的表达而促进肝癌细胞的增殖、侵袭和迁移。
IFITM3 expression and its regulatory action over MMP-9 in hepatocellular carcinoma
Objective: To investigate the expression of interferon-induced transmembrane protein 3 (IFITM3) in hepatocellular carcinoma (HCC), and its significance. Methods: The protein expression of IFITM3 along with matrix metallopeptidase 9 (MMP-9) in 60 specimens of HCC and paired cancer adjacent tissues were determined by immunohistochemical staining and Western blot analysis. IFITM3 small interfering RNA fragments (psilencer3.1-shIFITM3) were constructed and transfected into HCC HepG2 cells, and after transfection, the changes in mRNA and protein expressions of IFITM3 and MMP-9, proliferative capacity, as well as invasion and migration ability of the HepG2 cells were examined by qRTPCR, Western blot, CCK8 assay, and Transwell and scratch wound-healing assay, respectively. Results: Both positive expression rate and expression level of IFITM3 and MMP-9 protein expressions in HCC tissue were significantly increased compared with cancer adjacent tissue (positive expression rate: 81.67% vs. 13.33%; 88.33% vs. 8.33%, all P<0.05); in HepG2 cells after psilencer3.1-shIFITM3 transfection, both IFITM3 and MMP-9 expression were decreased at either mRNA or protein level, proliferation rate and the number of invaded cells were reduced, and wound closure was significantly delayed. The differences in all quantitative parameters had statistical significance (all P<0.05). Conclusion: IFITM3 expression is increased in HCC, and the high expressed IFITM3 may promote the proliferation, invasion and migration of HCC cells through regulating MMP-9 expression.